ethiopian tvet-system water supply and sanitation
TRANSCRIPT
Ethiopian TVET-System
Water supply and sanitation operation
Level II
Based on Feb 2017 G.C Occupational
Standard
Module Title: Installing and repairing water
services
TTLM Code: EIS WSO2 TTLM 0920v1
September, 2020
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Level II
Version1 September 2020
This module includes the following Learning Guides
LG25: Plan and prepare for service installation.
LG Code: EIS WSO2 M02LO1-LG-25
LG26: Drill and tap main pipe.
LG Code: EIS WSO2 M02LO2-LG-26
LG27: Install conduits under roads and pathways.
LG Code: EIS WSO2 M02LO3-LG-27
LG28: Install pipes and fittings.
LG Code: EIS WSO2 M02LO4-LG-28
LG29: Maintain water system hygiene.
LG Code: EIS WSO2 M02LO4-LG-29
LG30: Locate and repair leaks.
LG Code: EIS WSO2 M02LO4-LG-30
LG31: Test water service.
LG Code: EIS WSO2 M02LO4-LG-31
LG32: Finalize work.
LG Code: EIS WSO2 M02LO4-LG-32
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Level II
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Instruction Sheet Learning Guide #- 26
This learning guide is developed to provide you the necessary information regarding the
following content coverage and topics
Determining work requirements for installation of services
Determining materials and configuration
Determining location of other utilities and services
Identifying and applying system operation requirements.
Selecting, fitting and using Equipment
Determining Location, size and number of tapings from plans, specifications and
organizational procedures
This guide will also assist you to attain the learning outcome stated in the cover page.
Specifically, upon completion of this Learning Guide, you will be able to –
Determine work requirements for installation of services from plans, specifications and
organizational procedures.
Determine materials and configuration installation of services
Determine location of other utilities and services
Identify and apply system operation requirements.
Select, fit and use Equipment, including personal protective equipment are.
Determine Location, size and number of tapings
Learning Instructions:
1. Read the specific objectives of this Learning Guide.
2. Follow the instructions described below 3 to 6.
3. Read the information written in the information “Sheet 1, Sheet 2,sheet 3,sheet 4,sheet 5
and sheet” from page(4,10,15,20,24 and 35 respectively for each information sheet) and
Accomplish the “Self-check 1,Self-check 2,self-check 3, Self-check 4,Self-check 5, and
self-check 6 ” in page -8, 13,18,22, 33 and 37 respectively.
4. If you earned a satisfactory evaluation proceed to “Operation Sheet 1” in page _39
5. Then accomplish LAP Tests,”1, in page 40 (if you are ready). Request your teacher to
evaluate your performance and outputs. ensure you have a formative assessment and get
a satisfactory result;
6. Then proceed to the next LG
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Level II
Version1 September 2020
Information Sheet-1 Determining work requirements for installation of
services pipe
1.1. Introduction to service of pipe installation
Install and repair water service pipes are mainly focus from the main supply to the
consumer connection, these consumers may be domestic, municipal, industrial or
institutions.
A service pipe is a pipe connecting a main pipe (such as a gas or water main or an
electrical conduit) with a building. A "water-service" pipe line extends from the potable
water source to the interior of a building. Inside the building the "water-service" pipe
becomes a "water-distribution" pipe.
Figure1.1a examples of services pipe installation
Figure 1.1b examples of services pipe installation
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Installation Requirements for Water Service
We must inspect the entire length of water service piping outside the building before you
cover it. This includes water service piping that is:
Newly installed
Replaced
Repaired
General installation requirements Pipework must
comply with the durability requirements of Building Code clause B2 Durability
be compatible with the support
be installed to allow for thermal movement
be protected from freezing by insulation, or being buried below the level of freezing
be protected from damage
Be wrapped in flexible material or sleeved when penetrating masonry or concrete.
Requirements water lines
All work must be performed in compliance with the current Uniform Plumbing Code.
Connection of customer’s pipe must be to the city’s union only.
Outside service pipe must have no less than 2-feet of earth cover from all angles and at all
points.
Water pipe and fittings must be brass, copper, DI, SS, CPVC, HDPE, PE, PEX or PVC
manufactured to recognized standards for cold water distribution systems outside
buildings.
Plastic pipe must be a minimum of schedule 40, 160 PSI.
All piping must have an NSF or ASTM stamp approval.
All building supply pipe must be ¾-inch or larger.
1.1.1. confined space definition
Acceptable entry conditions - The conditions that must exist in a confined space before
entering to ensure that employees can safely enter into, and safely work within, the space.
Attendant - A designated individual stationed outside of one or more permit spaces who
assesses the status or authorized entrants, and who performs duties as specified by this
program.
Barrier - A physical obstruction that blocks or limits access.
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Confined space - Any space that is: Large enough and so configured that an employee
can bodily enter it has limited or restricted means for entry or exit, and is not designed for
Continuous employee occupancy. Examples include, but are not limited to: bins, boilers,
pits (e.g. elevator, escalator, pump, valve, etc.), manholes (e.g. sewer, storm drain,
electrical, communication, or other utility), storage tanks (e.g. fuel, chemical, water, other
liquid/solid/gas),
1.1.2 Lifting and moving materials in a trench
By forklift/telehandler
Ensure the forklift/telehandler has sufficient capacity and adequate fork length to lift the
equipment safely. (See capacity table).
Ensure all pins in the drag box are fully connected and secured by “R” clips before lifting.
Ensure that each lift occurs at the center of gravity. Lift only one item at a time. When
lifting the drag box position the forks in the center underside of the upper panel. Never lift
from the lower panel.
By crane/excavator
Ensure the crane/excavator has sufficient capacity and adequate chains to lift the
equipment safely. (See capacity table). Use good slinging practice at all times.
Ensure all pins in the drag box are fully connected and secured by “R” clips before lifting.
Ensure the chain(s) are connected to the four lifting points on the upper panel of the drag
box (two on each side of the panel) Lift only one box at a time.
Lifting Principles
1. Preparation
Before lifting or carrying, plan out your lift. Think about:
How heavy/awkward is the load? Should I use mechanical means (e.g. a hand truck) or
another person to help me with this lift? Is it possible to break the load into smaller parts?
Where am I going with the load? Is the path clear of obstructions, slippery areas,
overhangs, stairs, and other uneven surfaces? Are there closed doors that need to be
opened?
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2. Lifting
Keep your back straight during the lift by tightening the stomach muscles, bending at the
knees, keeping the load close and centered in front of you, and looking up and ahead. Get
a good handhold and do not twist while lifting.
Figure 1.1. lifting equipment
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Self-Check -1
Written Test
Directions: choose the best answer all the questions listed below. Use the Answer sheet
provided in the next page
I. Choose the best answer (3pts each)
1. Which one of the following is work requirement for service pipe installation?
A. All work must be performed in compliance with the current Uniform Plumbing Code.
B. Connection of customer’s pipe must be to the city’s union only.
C. Outside service pipe must have no less than 2-feet of earth cover from all angles and at all
points.
D. All building supply pipe must be ¾-inch or larger.
2. From the give alternative which one of the following is not lifting and moving equipment in
pipe installation
A. Excavator
B. Dozer
C. Pipe wrench
D. Loved
3. One of the following is not the principle of lifting plants
A. Preparation
B. Lifting
C. Carrying and Setting Down
D. Environment
Note: Satisfactory rating – 6 and above points Unsatisfactory - below 6 points
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Answer Sheet
Name: ____________________Date: _______________
Choose
1. ____
2. ______
3. _______
Score =
Rating=
Page 10 of 242
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Level II
Version1 September 2020
Information Sheet-2 Determining materials and configuration of
installation of service pipe
2.1. Introduction to material configuration
Preparing materials and configuration for service pipe Installations
Estimating the material requirement
As a plumber you are likely to do most of your estimation from site and this is done in the
absence of drawings or specifications.
The estimation process depends on what job you are doing.
components and fittings
How you are going to run the pipe work and what sizes you are going to use.
Once you have determined all this, it might be a good idea to produce a sketch of the
installation with dimensions on it by taking measurements from site.
This will help in working out the pipe work lengths
2.2. Inspect pipe material before installation
Things to look for:
Inspect for damage
Cracks, deformations, damaged coatings
Pipe Markings
ASTM, AASHTO or AWWA specification
diameter
Cell class for plastic, pressure class or rating
Production lot number
Name or trademark of manufacturer
NSF Standard 61 or 14 for potable water
Check that bands and fittings are correct size and type
2.2.1 PVC Pipe markings
The outside of PVC pipe must be labeled as follows:
Manufacturer's name or trademark (e.g. PPFA)
Standard to which it conforms (ASTM)
Pipe size
Material designation code
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DWV if for drainage
Pressure rating if for pressure
SDR number or schedule number
If the pipe is for potable water, a laboratory seal or mark attesting to suitability for potable
water
For those standards that cover several products, there must be additional markings to
indicate the pipe stiffness number, the SDR, the EB or DB number. A certifier's mar may
also be on the pipe.
Figure 2.1a PVC pipe marking
Do Not Use DWV (Drainage Waste Vent) Pipe when pressure pipe is specified
Figure 2.1b PVC pipe marking
A tapping machine is a mechanical device used to install the direct tapped connection into
water mains. The tapping machine may vary in design and operation depending on the
specific machine manufacturer.
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2.2. Determine the proper fitting for service pipe installation
Figure 2. Sample of fitting
Figure 2.2 Components of a direct tapping machine
The tapping machine shall provide a standard ratchet handle on the boring bar and be of a
design such that the cutting and tapping are controlled by a feed nut and yoke.
In no case should a hand-held drill be used.
The machine must operate with a cutting / tapping tool suitable for PVC pipe. This tool
should be of a shell-type design, have a minimum of two slots, and shall retain the cut
coupon after penetrating the PVC pipe wall
Figure 2.3 Combination of drill and tap tools
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Cutting/Tapping Tool: The combination drill and tap tool, Figure 2, illustrates the
recommended features of the cutter.
Self-Check -2
Written Test
Directions: Answer all the questions listed below. Use the Answer sheet provided in the next
page:
I. choose the best answer for the following question(2pts)
1. Which one of the following statements is true about Inspect pipe material before
installation?
A. Inspect for damage
B. Pipe Markings
C. NSF Standard 61 or 14 for potable water
D. Check that bands and fittings are correct size and type
2. Which one of the following statements are true about Estimating the material requirement?
A. Likely to do most of your estimation from site and this is done in the absence of drawings
or specifications.
B. The estimation process depends on what job you are doing.
C. To determine components and fittings
D. Run the pipe work and what sizes you are going to use.
E. all
3. before use of PVC we should be check the outside labeled of the pipe except :
A. Manufacturer's name or trademark (e.g. PPFA)
B. Standard to which it conforms (ASTM)
C. Pipe size and Material designation code
D. DWV if for drainage and Pressure rating if for pressure
E. All f. none
Page 14 of 242
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Answer Sheet
Name: ______________ Date: _______________
Short answer
1. _________
2. ________
3. __________
Score = ___________
Rating: ____________
Note: Satisfactory – 3 and above points Unsatisfactory - below 3 points
You can ask you teacher for the copy of the correct answers.
Page 15 of 242
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Information Sheet-3 Determining Location of Other Utilities and
Services
3.1. Introduction to utilities location and service
The successful functioning of the city and its many services depends on a complex
network of utilities for communications purposes and for the distribution of energy, water,
disposal of waste water and solid waste. While the core function of a utility (for example,
water supply or telecommunications) may not adversely affect the environment, the
structures that make the service possible (such as pumping stations, aerials or relay
stations) may be very visible in the environment.
Before installation of service pipe, one should first identify different utility lines in the area.
Utility location is the process of identifying and labeling public utility mains that are
underground. These mains may include lines for telecommunication, electricity
distribution, natural gas, cable television, fiber optics, traffic lights, street lights, storm
drains, water mains, and wastewater pipes. In some locations, major oil and gas pipelines,
national defense communication lines, mass transit, rail and road tunnels also compete for
space underground.
These lines may be identified from the municipal utility map.
Figure 3.1 utility location map
The above figure shows utility mapping by marking the locations of detected utility lines on
ground surface with survey flags or marking paint.
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Figure 3.2. Utility location legend
3.1.1public utility services
A public utility is a company that operates as a public-service corporation, and provides
essential services to the public such as electricity, telephone service, natural gas, water or
postal services. The public utility is typically regulated by the national, state or local
government.
Water supply systems get water from a variety of locations after appropriate treatment,
including groundwater (aquifers), surface water (lakes and rivers), and the sea through
desalination. The water treatment steps include, in most cases, purification, disinfection
through chlorination and sometimes fluoridation
Why Private Utility Locating Services Are Needed
Prior to digging or drilling on public or private property the responsible person must a
national organization that is responsible for the damage prevention of publicly owned
underground utilities. Despite the program's many successes, however, it suffers from the
following limitations:
Not all utility companies and municipalities participate in the program
Only underground utilities documented on as built will be marked out
The high volume of daily locates often causes mistakes to be made
Non-metallic, abandoned, and unknown lines cannot be located
The depth of underground utilities is not provided
The technicians have no direct contact with the excavator or driller
Non-conductive utilities are marked using as built, which are often outdated and
inaccurate.
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3.1.2 Relevant federal and state or territory legislation and regulations
The Water Supply (Water Fittings) Regulations are national requirements for the design,
materials, installation and maintenance of plumbing systems, water fittings and
appliances. Their purpose is to prevent waste, misuse, undue consumption and above all
the contamination of water supplies.
3.1.3 Codes of practice, associated standards and guidance material
A code of practice is a practical guide on how to comply with the legal duties under the
Work Health and Safety (WHS) Act and Regulations
A code of practice is intended to ensure the quality and functionality of plumbing systems
and to protect the health of the occupants of the premises where a plumbing system is to
be installed, as well as the health of the public in general.
Codes of practice:
deal with a duty or obligation under the WHS
Act or Regulation include known information about particular
hazards, risks and control measures help in determining what is reasonably
Practicable in the circumstances, and can be supplemented with other types of guidance
material.
3.1.4 Documenting organizational policies, manuals and induction programs
A policies and procedures manual are a comprehensive text that details every aspect of
company policy, the procedures for following those policies and the forms needed to
complete each process. A policies and procedures manual are a reference tool for
managers and supervisors.
3.1.5 Relevant community planning and development agreements, such as land care
agreements
A Real Estate Development Agreement (“Agreement”) is an agreement between an
individual and a construction company, city or builder to develop a parcel of land for the
individual's personal or commercial use. Once the owner approves the Plan, the
Developer may start work on the project.
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Self-Check -3
Written Test
Directions: choose the best answer all the questions listed below. Use the Answer
sheet provided in the next page
I. choose the best answer for the following question (2ptseach)
1. ___________is a company that operates as a public-service corporation, and provides
essential services to the public
A. public utility
B. Public health
C. Public running
D. Public responsibility
2. Which one of the following is not indicated by Codes of practice?
A. deal with a duty or obligation under the WHS
B. Act or Regulation include known information about particular
C. hazards, risks and control measures help in determining what is reasonably
D. Practicable in the circumstances, and can be supplemented with other types of guidance
material.
E. All F. none
3. Which one of the following does not apply during service pipe installation and repairing
process?
A. Rule and regulation of the organization
B. Policy and procedure of the organization
C. Standard and manual of the organization
D. Relevant community planning and development agreements
E. All F. none
Note: Satisfactory rating – 5 and above points Unsatisfactory - below 5 points
You can ask you teacher for the copy of the correct answers.
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Answer Sheet
Name: _________________________ Date: _______
1. ___________
2. __________
3. __________
Score = ______
Rating: _______
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Information Sheet-4 Identifying and applying system operation
requirements.
4.1. Introduction to system operation requirements
A piping system is generally considered to include the complete interconnection of must
be chosen to suit the operating conditions of the piping system. It is, however, very brittle
and is not suitable for most power plant services. tools to install, and are an important part
of piping and plumbing systems.
Operational Requirements are capabilities, performance measurement (Measures of
Effectiveness, Measures of Performance, Measures of Suitability & Technical
Performance Measurements) and processes needed to address mission area
deficiencies, evolving threats, emerging technologies, or weapon system cost
improvements.
The operational requirement definition process includes the following activities:
Identify stakeholders who will or should have an interest in the system throughout its
entire life cycle.
Elicit requirements for what the system must accomplish and how well. Doing this in the
form of operational scenarios and/or use cases can be particularly helpful in discussions
with end users.
Define constraints imposed by agreements or interfaces with legacy or co-evolving
enabling systems.
4.2. Pipe Installation, Maintenance and Repair Requirement
Water Main Design
Flushing Requirements to Maintain 2.5 fps Sediment Removal Velocity
Pipe Restraining Requirements
Pipelines need to be restrained at all valves, bends, tees, crosses and dead ends for a
specified distance dependent on the size of the pipe and the water flow
Pipe Bedding Requirements for Water Main Support and Protection
Trench Requirements for Installation and Repair of Water Main
Trench safety during repair and maintenance to underground water facilities on of the
most dangerous parts of a small water systems operator’s responsibilities.
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OSHA Requirements
Disinfection Requirements for New Water Main
Water System Mapping Requirement
Requirements to a Valve Exercising and Main Flushing Program
Unique Valve identification number. . information collected
Visibility and proper elevation
Accessibility
Location and GPS coordinates
Manufacturer
Size and Style of Valve
Number or turns and direction for opening
Check for leakage with detection equipment
Condition of valve
Age of valve in system
Tank Maintenance and Inspection Requirements
Requirements for Repairing Broken Water Mains
Minimum Precautions to Prevent Contamination During Repairs
The following system operational requirement should be applied while installing service
pipe
Use proper equipment
Use proper safety procedures
Don’t over tighten machine on pipe
Apply approved lubricant to sharp core cutter
Cut and thread “slow and steady”
Use Teflon tape on corporation stop
Remember to tap slow & steady
Follow procedures in compliance with any or all occupational health and safety
Regulations in your area
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Self-Check -4
Written Test
Directions: Answer all the questions listed below. Use the Answer sheet provided in the
next page:
I. Choose the best answer for the following question (3pts each)
1. One of the following does not needs to operational or system requirement of in water
distribution
A. Pipe Installation B. Maintenance and repair of pipe
C. Water storage D. All
2. following system operational requirement should be applied while installing service pipe
except
A. Use proper equipment and safety procedures
B. Don’t over tighten machine on pipe and Apply approved lubricant to sharp core cutter
C. Cut and thread “slow and steady” Use Teflon tape on corporation stop
D. Remember to tap slow & steady
E. All. F. None
3. Which one is not the requirement for Water Transmission and Distribution Systems?
A. Water main design
B. OSHA Requirements and Disinfection Requirements for New Water Main
C. Water System Mapping
D. Requirements to a Valve Exercising and Main Flushing Program
E. All F. None
4. ______ are capabilities, performance measurement and processes needed to address
mission area deficiencies, evolving threats, emerging technologies, or weapon system
cost improvements
A. Operational requirement
B. Laboratory requirement
C. Excavation requirement
D. Installation requirement
Satisfactory rating – 6and above points Unsatisfactory - below 6 points
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Answer Sheet
Name: _________________________ Date: _______________
1. __________________
2. ___________________
3. _____________________
4. _______________________
Score = ___________
Rating: ____________
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Information Sheet-5 Selecting, fitting and using Equipment, including
personal protective equipment
5.1. Introduction tools, fitting and equipment
A major concern when choosing the appropriate type of equipment and tools for
construction works is:
Its availability in the region or vicinity to the work site,
how to deliver it to the work site,
How easy is it to operate and how easily it can be reversed?
its cost and reliability, and
The availability of spare parts and repair facilities.
There are a large number of tools and devices which are commonly used in fitting work.
Generally, all the tools may be classified as follows:
Marking and measuring tools.
Holding and supporting tools.
Cutting, filing and scraping tools.
Striking tools.
Drilling, dyeing, reaming and tapping tools.
Miscellaneous tools
The following tools and equipment should be selected and checked against specification
for construction and installation of water distribution and wastewater collection system
Table 5. Tools for laying out, fitting and installing pipe
Laying out
Pipe Cutting &
Threading
Installation
Tape measure
Pipe vise Teflon tape &
pipe seal
Test gauge for final
pressure test
Scriber Hacksaw Pipe wrench Set of pipe clamps,
fixtures
Soapstone or pencil Pipe cutter Chain wrench
Set of wall plug
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The necessary equipment used for tapping and drilling operation should be selected and
fitted for use.
The various types of PPE used for drilling and tapping operation are the following
Safety Google
Gloves (rubber, leather, or leather palm):
Dust Masks
Hard Hat and Safety Shoes
Ear Plugs
Water Buckets & Soap
Fire Extinguisher
Eye Wash Kit
First Aid Kit
Insulating gloves
Personal protective equipment
5.2. Hand and power tools and equipment selection
Table 5.1. Basic plumbing hand tools
Tape measure Claw hammer
Hack saw Various adjustable wrenches
Multi tip screwdriver Ball-pien hammer
Regular and stubby screwdrivers Needle-nose pliers
Vise grip pliers Side cutters
Cold/wood chisels 2ft level
Allen keys imperial/metric Socket set
Files, round/flat Crow bar
Shovels, long/short Tin snips
Step ladder Caulking gun
Safety, Gloves/goggles/ear plugs Sledge hammer
Mechanical level File half−round Adjustable
wrench
Set of masonry drill
bits
Plumb−bob Deburrer Vise grip
Electric drill machine
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Flashlight, small/large Drywall knife/ box cutter
Trowel Hand saw
Hole saw kit Wire strippers
5.3. Mechanical excavation, Lifting and winching equipment
Figure 5. Lifting and excavation equipment
5.4. Pneumatic and motorized equipment
Pneumatic equipment including pressure reducing valves, electric valves, pressure control
valves and more are available from All Air Incorporated. When you need vacuum valve
components, flow control valve products or pneumatic valves, contact us. We also offer
filters, regulators and lubricators from Watts Parker, as well as after coolers from Arrow
Pneumatics. Pressure drilling and tapping machines.
Table 5.2. Pressure drilling and tapping machines
Installation
Teflon tape & pipe seal Test gauge for final pressure test
Pipe wrench
Set of pipe clamps, fixtures
Chain wrench
Set of wall plug
Adjustable wrench Set of masonry drill bits
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5.5. Pipe Cutting & Threading, Thread cutting equipment
Table 5.3. Pipe Cutting & Threading, Thread cutting equipment
Mini pipe cutter
Medium copper pipe cutter 2"
PEX Crimpers
PEX cinch ring crimper
Steel pipe cutter
PVC Hand saw
Spud wrench
Flaring tool kit
Pipe wrenches
6"/10"/14"/18"/24"
Offset pipe wrench 14"
Vise grip
Electric drill machine
Hammer
Set of combination wrench
Cold chisel
Set of screw driver
Excavator Compactor
Dozer Pipe vice
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Offset hex wrench
Strap wrench
Cast iron snap cutter
Basin wrench / telescopic
Torpedo level Pipe extractors
Pipe tapping tools
Ratcheting pipe threading set
Internal pipe wrench Plastic tube cutter/ scissor type
Internal pipe cutter
Spring benders various sizes
Pipe reamer
Torch head / Turbo torch
Sparking igniter
Gasket cutter / punches
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Fire extinguisher
Faucet seat extractor
Faucet seat refinisher Faucet handle puller
Plunger Sink plunger
Pipe wrench
Pipe-vices
5.6. Communication equipment
5.7.1. Work effectively as part of a team
Here are some effective ways to improve team efficiency and productivity while being a part
of the team and not just a boss.
Delegate Responsibility
Let team members utilize their talents and take on some tasks that you would normally do.
Communicate Effectively
Know their Strengths and Weaknesses
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Everyone has their strengths and weaknesses at work. The more you know about your
employees, the easier it will be for you to match the right employees with certain tasks.
Give them Incentives
Everyone works better when they know that there are extra incentives involved.
Be a Good Example
Your employees look to you as their leader, so behave like one.
Hold Stand-Up Meetings
We spend far too much time sitting all day at work, so a stand-up meeting is a great way to
stretch out those stiff limbs, and get a lot done. These meetings are basically a huddle, and
you are acting more like a team.
Set Realistic Goals
Business goals should be realistic and attainable. If employees think that they are never
going to reach your goals, they are not going to be interested in working hard.
Learn to Love Technology
As a team leader, you need to take advantage of the latest software, hardware, and
information technology. The more tools you have, the easier it is going to be to be productive
and efficient.
5.7. Bridging clamps one type of clamps we offer are the "Bridge Clamps" which are used
to secure hoses onto a pipe or connector. Bridge clamps are used to secure hoses at
connection points, and since the flat band clamps snugly around the material between
the raised helix of the hose, a more secure connection is made possible.
Square spindle heads stand up to heavy wrench tightening.
A: Drop Forged Frame: USA Made Steel is Heat Treated For Greater Strength Under Heavy
Load
B: Black Oxide Coating: Spindles are treated to Resist Corrosion
C: Highest Clamping Pressure: Ranging Up to 40,000 lbs. Standing Up to the Demands of
the Heaviest Industrial Applications
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Figure 5.1 Bridging clamps
There are several types of pipe joints, but their selection depends on pipe sizes, material and
flow pressure etc.
Different types of pipe joints used in plumbing system are as follows.
Threaded joint
Brazed joint.
Brazing is a metal-joining process in which two or more metal items are joined together by
melting and flowing a filler metal into the joint, the filler metal having a lower melting point
than the adjoining metal.
A major advantage of brazing is the ability to join the same or different metals with
considerable strength
Soldered joint.
Welded joint (butt welded; socket welded)
Flanged joint.
Compression joint.
Grooved joint.
Manipulative mechanical jointing uses brass fittings to make copper pipe connections. A
nut is placed over the end of the pipe and a swaging (crox) tool is inserted to expand the
pipe, creating a rolled groove to secure the nut in position. The joined ends are made
watertight using plumbers’ hemp or thread tape.
Non-manipulative jointing also uses brass fittings, but instead of expanding the pipe with a
swaging tool, a brass ‘olive’ is placed over the pipe and compressed between the nut and
fitting to create a secure joint that can easily be separated later.
Sliding sleeve uses a sleeve that is placed over the pipe end and then expanded to go over
the serrated spigot. A special tool forces the sleeve over the pipe and spigot to create an
effective joint. Sleeves can be removed with the application of heat and then reused.
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Heat fusion welding is where the surface of the pipe and connection are melted together
using a heating iron. As the two ends are overlapped and fused without the application of
welding fillers, the result is effectively a continuous pipe.
Solvent cement welding also overlaps and fuses the pipes but uses a solvent to ‘glue’ the
pipes together.
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Self-Check -5
Written Test
Directions: choose the best answer all the questions listed below. Use the Answer sheet
provided in the next page
I. Choose the best answer (3pts each)
1. ______is a metal-joining process in which two or more metal items are joined together by
melting and flowing a filler metal into the joint.
A. Brazing B. Solvent cement joint
C. Soldered joint. D. flanged joint
2. _________is where the surface of the pipe and connection are melted together using a
heating iron
A. Heat fusion welding B. Manipulative mechanical jointing
C.Non-manipulative jointing D.Solvent cement welding
3. Large number of tools and devices which are commonly used in fitting work. Generally,
A. all the tools may be classified as follows except
B. Marking and measuring tools.
C. Holding and supporting tools.
D. Cutting, filing and scraping tools
E. Striking tools and Drilling, dyeing, reaming and tapping tool
B. All f. none
4. Which one of the following tools are not used to service pipe installation?
A. Teflon tape & pipe seal
B. Pipe wrench and Chain wrench
C. Adjustable wrench and Vise grip
D. Flow velocity
Note: Satisfactory rating – 6 and above points Unsatisfactory - below 6 points
You can ask you teacher for the copy of the correct answers.
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Answer Sheet
Name: _________________________ Date: _______________
Choose answer
1. ______
2. _______
3. _______
4. _______
Score = ___________
Rating: ____________
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Information Sheet-6 Determining Location, size and number of tapings
6.1. Introduction to material location of service tap
Service Taps: Service taps are easily made either before or after Ductile Iron Pipe
installation.
The minimum pressure class of all diameters of Ductile Iron Pipe may be direct tapped for
3/4-inch services. Additionally, the minimum pressure class of 6-inch and larger Ductile Iron
Pipe may be direct tapped for 1-inch services.
figure 6. polyethylene tapping
The preferred and recommended method of making direct service taps on polyethylene
encased pipe consists of applying two or three wraps of polyethylene adhesive tape
completely around the pipe to cover the area where the tapping machine and chain will be
mounted.
Figure 6.1. Making direct service taps on polyethylene encased pipe
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6.2. Location of tapping
The appropriate location of tapping can be identified according to the following condition
At a shorter distance from the house or industrial area where the water is required
At a place where there is no obstruction
A tap must be at least 24 inches from the end of the pipe, at least 2 inches from other taps
axially (along the length of the pipe),
At least 2 inches apart radially (about the girth of the pipe).
Alternately the taps may be 36” apart with no separation radially.
Multiple taps on the same side of the pipe must be staggered.
6.2.1. Maximum Size Taps
The maximum size and number of corporations stops permissible for
various main sizes are usually set by local codes, generally the plumbing code. Necessary
pipe thicknesses for different tap sizes are outlined in tables.
Table 6. Recommended Direct Tap Size for 3- Through 24-inch Ductile Iron Pipe
Large Connections: Large services are provided for schools, factories, and other
facilities by using a tee or by placing a split tapping sleeve or tapping saddle on the pipe
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Self-Check -6 Written Test
Directions: Answer all the questions listed below. Use the Answer sheet provided in the next
page:
I. Choose the best answer for the following question (2pts)
1. The appropriate location of tapping can be identified according to the following condition
except
A. At a place where there is no obstruction
B. at least 2 inches apart radially (about the girth of the pipe).
C. Alternately the taps may be 36” apart with no separation radially.
D. Multiple taps on the same side of the pipe must be staggered.
E. All F. none
2. _____are easily made either before or after Ductile Iron Pipe installation
A. Service taps
B. Pipe wrench
C. Pipe cutter
D. Gate valve
3. Which one of the following statements is true about determining the location, size and
number of tapping in service pipe installation?
A. To identify the problem easily which occurs in service pipe
B. To reduce wastage of tapping
C. To connect the service pipe and accessories easily
D. All
4. The size of tapping depending on
A. The size of the pipe /diameter
B. The length of the pipe
C. The roughness of the pipe
D. All
Note: Satisfactory rating – 4 & above points Unsatisfactory - below 4 points
You can ask you teacher for the copy of the correct answers.
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Answer Sheet
Name: ___________________ Date: ______________
1. _____________
2. _____________
3. _____________
Score = ___________
Rating: ____________
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Operation Sheet _1 Performing Utility Location
Steps to Utility Locating
1. Select appropriate PPE, tools and equipment
2. Review old as-built and interview facilities personnel regarding whereabouts of above
ground and underground utilities.
3. Perform an initial on-site consultation with the client to determine the scope of work
4. Perform a visual inspection of the site, survey area, and inside all utility vaults and nearby
buildings to search for visual evidence of underground utilities.
5. Conduct an active mode cable and pipe locator survey by applying a radio signal to all
accessible conductive wires by wrapping a transmitter clamp around them; to metallic
conduits and pipes via direct connection of an alligator clamp to their metal surfaces; and
snake all non-metallic pipes and conduits with a detectable duct rod.
6. Conduct a passive mode cable and pipe locator survey via power, radio, and induction
mode to search for inaccessible high voltage electric (HVE), telecommunication lines, and
inaccessible, abandoned and unknown lines.
7. Conduct a ground-penetrating radar (GPR) survey to search for inaccessible, abandoned
and unknown lines.
8. Designate the location and depth of underground utilities with paint and/flags, using
AWPA color codes (PDF).
9. Perform a final on-site consultation with the client to explain the results of the survey,
including a thorough explanation of any limitations or areas of concern.
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Name: _____________________________ Date: ________________
Time started: ________________________ Time finished: ________________
Instructions: Given necessary templates, tools and materials you are required to perform
the following tasks within 6 hours.
Task 1. Perform Utility Location
LAP Test Practical Demonstration
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Instruction Sheet Learning Guide #- 26
This learning guide is developed to provide you the necessary information regarding the
following content coverage and topics –
operating tapping machine Setting up
Installing main tap.
Recognizing and correcting faults or malfunctions in drilling and tapping.
Applying Corrosion and protection measure
This guide will also assist you to attain the learning outcome stated in the cover page.
Specifically, upon completion of this Learning Guide, you will be able to –
Operate tap machine Setting up
Install main tap
Recognize and correct faults or malfunctions in drilling and tapping.
Apply Corrosion and protection measure
Learning Instructions:
1. Read the specific objectives of this Learning Guide.
2. Follow the instructions described below 3 to 6.
3. Read the information written in the information “Sheet , Sheet 2,sheet 3 and sheet 4,sheet
in page for each information sheet (42,51,54and 61 respectively) and Accomplish the
“Self-check1,Self-check2,self-check3and Self-check4,”in page
49,53,59,and67)respectively.
4. If you earned a satisfactory evaluation proceed to “Operation Sheet 1” in page 69
5. Then accomplish LAP Tests(activity),”1and 2, in page 72 (if you are ready). Request your
teacher to evaluate your performance and outputs. ensure you have a formative
assessment and get a satisfactory result;
6. Then proceed to the next LG
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Information Sheet-1 Operating Tapping Machine Setting Up
1.1. Introduction to drilling and tapping
Tapping is the process of cutting a thread inside a hole so that a cap screw or bolt can be
threaded into the hole. Also, it is used to make thread on nuts. Drilling and tapping are
two distinct actions. Drilling refers to creating a smooth hole in a material with a drill and
motor.
1.2. Setting up and operate tapping machine
Before using tapping machine
Clean and oil all bearing and wear surfaces and threads.
Inspect and clean tapping bits, and remove chips and scale.
Inspect and clean the Boring Bar tool end. Chips and scale may interfere with the insertion
of the tapping bit or adapter shank.
After using
Clean the machine and oil the machined surfaces. If necessary, the top and bottom
chambers can be easily disassembled to clean more thoroughly.
Lubricate the tool holding area of the boring bar
Flush the bottom chamber with a water hose to remove any chips. DO NOT hammer
frames to remove chips or debris -Handle Carefully
Protect threaded pieces by assembling them with their mating parts.
Periodically, inspect the Boring Bar’s o-ring seals and replace if worn.
Carefully, place the tool back in the toolbox for storage.
Placing of the machine
The machine should fit on the drilling site firmly, but not in a way that will set up wall
stresses by distorting the pipe.
Saddle O.D. must match pipe O.D.
Mount the machine so both tightening nuts are accessible and tighten both sides evenly. If
a strap is used, tighten the strap so the machine does not slip.
Tighten sufficiently to the gasket and hold the machine in place during the taping
operation. Further tightening is not necessary.
Cutting tool must be lubricated with an approved lubricant. This will help reduce the heat
generated when cutting.
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Once the machine has been properly placed, place tapping blanket over assembly. This is
a safety precaution.
Water mains are usually cast iron, 8 inches or more in diameter. If the main is less
than 8 inches in diameter, taps should be 2 inches or smaller.
The hole
Cut the hole; don’t punch it. Rotate the ratchet handle one complete turn for every one-
eighth turn of feed yoke, approximately 25mm (1") movement of feed nut to each one-
quarter turn of ratchet handle.
During a proper tapping operation, the boring bar should rotate easily. If unusual
resistance is encountered, the feed yoke is being advanced at too high a rate.
When making the threads, allow the tap to feed itself after it has a start. When withdrawing
the cutter, the upward force will be about 0.6 Newtons per kilopascal (1-pound force per
1psi) line pressure.
The coupon
When “Coupon” is Removed
the coupon (the core of material held in the cutter head) is a good indicator of correct
tapping procedure. Keep the coupons to check quality of tap
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Checking the “Coupon”
The condition of the coupon provides a check of incorrect tapping procedure.
At the first sign of a “crown” or striations on the coupons, the tapping procedure or the
condition of the tools should be reexamined and corrected before more taps are
attempted.
Inserting the stop
Inserting the Corporation Stop
For direct tapping, the maximum size of stop is 25mm (1"). Remember to wrap Teflon tape
around the threads. Approximately three threads will show when stop is properly seated.
Replace top on machine. Open “equalizing” valve, and push boring bar down by hand.
Hook feed yoke on boring bar and rotate ratchet handle while applying finger pressure to
the feed nut. Do not force the first few threads
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Dry taps
When tapping dry, the same cutting tools are recommended; procedures are similar to
those for wet tapping.
Once the tapping operation is complete, the machine can be removed and the tapped hole
cleared of all cuttings before inserting the stop by hand. Wrapping with Teflon tape is
recommended.
Do not cross-thread the stop. Tighten the stop to the point where approximately three
threads are showing.
Saddle taps
Saddles to make taps in pipe are available for any size or class of pipe. A service saddle
or clamp can be used to make connections up to a maximum size of 50mm (2"). Above
this size, a tapping sleeve and valve is required. Saddles recommended for use for PVC
Pressure pipe must provide
a full circle of support around the pipe
at least 50mm (2") wide straps around the entire pipe circumference
a body that is accurately contoured to the outside diameter of the pipe
No distorted bearing points after it has been tightened.
Evenly tighten the saddle to the pipe.
Apply Teflon and screw the inlet side of the main stop into the saddle threads.
Open the main stop.
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Using the appropriate adapter and gasket, attach the drilling machine to the main stop
outlet threads. Use a machine with an operator-controlled feed rate. The use of a core drill
is essential. Follow the machine manufacturer’s instructions.
Lower the boring bar to the main and rotate the cutter while exerting finger-pull on the feed
handle.
Withdraw the cutter; close the main stop and remove the drilling machine.
The connecting copper service pipe can be bent into a “gooseneck” from the corporation
stop to allow for expansion/contraction and soil settlement. It also reduces the stress on
the stop itself and allows easier assembly.
IPEX’s “Pipe with a Stripe” PE tubing need not be goose necked.
Installing an upward gooseneck causes the service pipe to rise above the grade line and
invites frozen services.
Making the tap at the side of the main and goose necking the service pipe horizontally will
reduce frozen services.
Saddle procedure
Water Saddle Tapping Equipment
Tapping Machine
Slotted Core-cutting Tool, Shell Design - Minimum 2 slots
Corporation Stop
Manufacturer-approved tapping lubricant
Teflon Tape
The Common Sense of Tapping (with any pipe)
1. Follow procedures in compliance with any or all occupational health and safety
regulations in your area.
2. Use proper equipment including safety goggles and heavy protection blanket. The
blanket should be about 1.2m x 1.8m (4' x 6') in size and should have a hole in the center
to permit installation of the tapping machine.
3. Don’t over tighten machine on pipe.
4. Apply approved lubricant to sharp core cutter.
5. Cut and thread “slow and steady.”
6. Use Teflon® tape on corporation stop.
7. Remember to tap slow and steady.
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“Tapping” is the process of connecting a branch line to a main line by cutting a hole into
the main. For tapping of pressure pipe, branch lines can range in size from small service
lines which supply individual homes to large outlets for industrial users.
Service connections to water mains are accomplished in the field via:
Direct tapping into the pipe wall
Tapping through service saddles
Tapping large service connections through tapping sleeves
Using fabricated or injection-molded couplings with threaded outlets Fabricated or
injection-molded tapped couplings are in-line fittings that are installed during original
construction.
Direct taps – the branch line is connected to the main by a corporation stop that is
screwed directly into the pipe wall. Maximum branch line size is 1-inch.
Figure 1. Direct tap
Saddle taps – the branch line is connected to a main by a corporation stop that is
screwed into a metal saddle that wraps around the pipe. Maximum branch line size is 2-
inch.
Figure 1.2. Saddle taps
Sleeve taps – the branch line is joined to the main via a connection at a metal sleeve that
wraps around the pipe. Maximum branch size is the same as the main.
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Figure 1.3. Sleeve tape
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Self-Check -1
Written Test
Directions: choose the best answer all the questions listed below. Use the Answer sheet
provided in the next page
I. Choose the best answer for the following question (2pts each)
1. ________ is the process of cutting a thread inside a hole so that a cap screw or bolt can
be threaded into the hole.
A. Tapping B. Drilling C. Threading D. Digging
1. Which one of the following statements is true about Common Sense of Tapping for any
type of pipe?
A. Follow procedures in compliance with any or all occupational health and safety regulations
in your area.
B. Use proper equipment including safety goggles and heavy protection blanket.
C. Don’t over tighten machine on pipe and Apply approved lubricant to sharp core cutter.
D. Cut and thread slow and steady and Use tape on corporation stop E. All F. none
2. Which one of the following statements is true about PVC service pipe connection?
A. Direct tapping cannot recommend
B. New connection use tap tee
C. Tapping to be completed with service saddle
D. Service connection should be a minimum of 1m from adjacent service, pipe bell or fitting
E. All F. none
3. From the give alternative which one of the following equipment are used to saddle type of
tapping
A. Tapping Machine B. Slotted Core-cutting Tool, Shell Design - Minimum 2 slots
c.Corporation Stop D. Manufacturer-approved tapping lubricant E. all F. none
4. _________refers to creating a smooth hole in a material with a drill and motor
A. Drilling B. Tapping C. Connecting D. Adjusting
Score = ___________
Rating: ____________
Note: Satisfactory rating – 5 and above points Unsatisfactory - below 5 points
You can ask you teacher for the copy of the correct answers.
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Answer Sheet
Name: _________________________ Date: _______________
Choose
1. ____
2. ______
3. _______
4. ___
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Information Sheet-2 Installing main tap.
2.1. Introduction installing taps
A tap is installed using a pressure-contained tapping machine to attach a tapping valve to
the existing pipeline. Tapping uses a nozzle or split tee welded to the surface of the
existing pressurized pipe
Hot tapping, or pressure tapping, is the method of making a connection to
existing piping or pressure vessels without the interrupting or emptying of that section of
pipe or vessel. This means that a pipe or tank can continue to be in operation whilst
maintenance or modifications are being done to it. The process is also used to drain off
pressurized casing fluids and add test points or various sensors such as temperature and
pressure. Hot taps can range from a ½ inch hole designed for something as simple as
quality control testing, up to a 48 inch tap for the installation of a variety of ports, valves, t-
sections or other pipes.
Pipe Tapping installing Guides
Do’s & Don’ts
Use proper equipment
Use proper safety procedures
Don’t over tighten machine on pipe
Apply approved lubricant to sharp core cutter
Cut and thread “slow and steady”
Use Teflon® tape on corporation stop
Tighten main stop to 37 Joules (27 ft.lbs.)
If saddle is used, straps should be at least 50mm (2") wide
Remember to tap slow & steady
Tapping machines vary from one manufacturer to another. Below is a general description
of the tapping method.
Screw the main cock into the saddle after removing the plug.
Install the hole-cutting tool into the tapping machine. The tool should be long enough to
cut throughout the pipe.
Start drilling. These machines could be operated manually, pneumatically or electrically.
The drill is then raised and the plug closed.
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Unscrew the drilling machine.
Figure. 2 install tapping sample
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Self-Check -2
Written Test
Directions: Answer all the questions listed below. Use the Answer sheet provided in the next
page:
I.Choose the best answer for the following question(5pts)
1. One of the following does not refers to a guide line for installing main tap
A. Use proper equipment
B. Use proper safety procedures
C. Don’t over tighten machine on pipe
D. Apply approved lubricant to sharp core cutter
E. Cut and thread slow and steady
2. Which one of the following is not the is a general description of the tapping method?
A. Screw the main cock into the saddle after removing the plug.
B. Install the hole-cutting tool into the tapping machine. The tool should be long enough to
cut throughout the pipe.
C. Start drilling. These machines could be operated manually, pneumatically or electrically.
D. The drill is then raised and the plug closed and Unscrew the drilling machine. e. all f.
none
3. _____ is installed using a pressure-contained tapping machine to attach a tapping valve to
the existing pipeline.
A. Tap
B. Union
C. Reduce
D. Tee
Note: Satisfactory rating – 7.5 and points Unsatisfactory - below 7.5 points
You can ask you teacher for the copy of the correct answers.
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Answer Sheet
Name: _________________________ Date: _______
1. ________
2. _________
3. _________
Score = ______
Rating: _____
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Information Sheet-3 Recognizing and correcting faults or malfunctions
in drilling and tapping.
3.1. Introduction to faults and malfunction
The general approach to assessing the potential effects of the selected accident,
malfunction, or unplanned event scenarios involves:
consideration of the potential event that could occur during the life of the Project
description of the Project planning and safeguards established to minimize the potential
for such occurrences to happen
consideration of the contingency or emergency response procedures applicable to the
event; and
a determination of the significance of the potential residual environmental effects in the
unlikely event that these accidents, malfunctions, or unplanned events do happen.
3.2. Identification of Credible Accidents, Malfunctions, or Unplanned Events
Based on the nature of the Project, knowledge of the environment within which the Project
is located, as well as the experience of the Proponent, the following credible accidents,
malfunctions, and unplanned events have been selected for consideration in this
assessment and are described in greater detail in the following sections:
Fault Codes
O = oversized or bell-mouthed tapped holes
p = poor finish threads
t = tap teeth chipping
e = excessive rate of wear on tap
b = broken tap
c = cold welding or galling
Faults Causes
misalignment o-p-t
tap lead reground or eccentric o
incorrect feed rate o-p
wrong type of tap for job o-p-e-b
blunt tap p-e-b-c
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incorrect sharpening of tap o-p-t-e-b-c
lack of or incorrect lubricant o-p-e-b-c
tap hitting bottom of hole t-b
tap speed too high e-b-c
work hardened skin in drill hole e-b
machine requires overhaul o-p-t-b
chips not being removed properly p-b
tap drill size incorrect o-b
material too soft c
incorrect material structure c
Table 3. Drilling and taping problems and solution
Problem Solution
Oversize Pitch
Diameter
Incorrect tap 1. Use proper GH limits of taps.
2. Use longer chamfered taps
Chip packing 1. Use spiral point or spiral fluted taps.
2. Reduce number of flutes to provide extra chip room.
3. Use larger hole size.
4. If tapping a blind hole, allow deeper holes where applicable or
shorten the thread length of the parts.
5. Use proper lubricant.
Galling 1. Apply proper surface treatment.
2. Use proper cutting lubricant.
3. Reduce tapping speed.
4. Use proper cutting angle in accordance with material being tapped.
5. Use larger hole size.
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Operating conditions 1. Apply proper tapping speed.
2. Correct alignment of tap and drilled hole.
3. Use proper tapping speed to avoid torn or rough threads.
4. Use lead screw tapper.
5. Use proper tapping machine with suitable power.
6. Avoid misalignment of the tap and drilled hole from loose spindle or
worn holder.
Tool conditions 1. Obtain proper indexing angle for the flutes at the cutting edge.
2. Grind proper cutting angle and chamfer angle.
3. Avoid too narrow a land width.
4. Remove burrs from regrinding.
Problem Solution
Oversize Internal
Diameter
Hole size 1. Use minimum hole size.
2. Avoid tapered hole.
3. Use proper chamfered taps.
Galling 1. Apply proper surface treatment such as steam oxide or TiN.
2. Use proper cutting lubricant.
3. Reduce tapping speed.
4. Use proper cutting angle in accordance with material being tapped.
Problem Solution
Undersize Pitch
Diameter
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Incorrect tap 1. Use oversize taps for cutting materials such as copper alloy,
aluminum alloy, and cast iron.
2. Use oversize taps for cutting tubing which will have "spring back"
action after tapping.
3. Apply proper chamfer angle.
4. Increase cutting angle.
Damaged thread Use proper reversing speed to avoid damaging tapped thread on the
way out of the hole.
Left-over chips 1. Increase cutting performance to avoid any left over chips in the
hole.
2. Remove left over chips from the hole for gage checking.
Problem Solution
Undersize Internal
Diameter
Hole diameter Use maximum drill size.
Problem Solution
Torn / Rough Thread
Chamfer too short Increase chamfer length.
Wrong cutting angle Apply proper cutting angle.
Galling 1. Use thread relieved taps.
2. Reduce land width.
3. Apply surface treatment such as steam oxide or TiN.
4. Use proper cutting lubricant.
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5. Reduce tapping speed.
6. Use larger hole size.
7. Obtain proper alignment between tap and work.
Chip packing 1. Use spiral pointed or spiral fluted taps.
2. Use larger drill size.
Problem Solution
Chattering on
Tapped Thread
Too free cutting 1. Reduce cutting angle.
2. Reduce amount of thread relief.
Tool conditions 1. Avoid too narrow a land.
2. Do not grind the bottom of the flute.
Problem Solution
Breakage
Incorrect tap
selection
1. Avoid chip packing in the flutes or the bottom of the hole. Use spiral
pointed or spiral fluted taps or fluteless taps.
2. Apply correct surface treatment such as steam oxide or TiN.
Excessive tapping
torque 1. Use larger drill size.
2. Try to shorten thread length.
3. Increase cutting angle.
4. Use a tap with more thread relief and reduced land width.
5. Use spiral pointed or spiral fluted taps.
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Operating conditions 1. Reduce tapping speed.
2. Avoid misalignment between tap and the hole and tapered hole.
3. Use floating type of tapping holder.
4. Use tapping holder with torque adjustment.
5. Avoid hitting bottom of the hole with tap.
Tool conditions 1. Do not grind the bottom of the flute.
2. Avoid too narrow a land width.
3. Remove all worn sections when regrinding the flutes.
4. Regrind tool more frequently.
Problem Solution
Chipping
Incorrect tap
selection 1. Reduce cutting angle.
2. Use different kind of high-speed steel tap.
3. Reduce hardness of the tap.
4. Increase chamfer length.
5. Avoid chip packing in the flutes or in the bottom of the hole by using
spiral fluted or spiral pointed taps.
Operating conditions 1. Reduce tapping speed.
2. Avoid misalignment between tap and hole.
3. Avoid sudden return of reverse in blind hole tapping.
4. Avoid galling.
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Self-Check -3
Written Test
Directions: choose the best answer all the questions listed below. Use the Answer sheet
provided in the next page
I. Choose the best answer for the following question (2pts each)
1. Which one of the following is a solution when there is a problem on operation condition of
drilling and tapping?
A. Reducing tapping speed B. Apply proper cutting lubricants
B. Avoid work hardening and use lager hole size C ..All E. none
2. Which one of the following is a solution when there is a problem on incorrect tap
selection?
A. Use specially designed tap for tapping heat treated material
B. Change to a type of high-speed steel tap C. Apply special surface treatment
C. Increase chamfer length D.All F. none
3. Mach faults with their cause (1p each)
Faults Causes
1 misalignment A. oversized or bell-mouthed
tapped holes
B. poor finish threads
C. tap teeth chipping
D. excessive rate of wear on tap
E. broken tap
F. cold welding or galling
2 tap lead reground or eccentric
3 incorrect feed rate
4 wrong type of tap for job
5 blunt tap
6 incorrect sharpening of tap
7 lack of or incorrect lubricant
8 tap hitting bottom of hole
9 tap speed too high
10 work hardened skin in drill hole
11 machine requires overhaul
12 chips not being removed properly
13 tap drill size incorrect
14 material too soft
13 incorrect material structure
Note: Satisfactory rating – 8.5 and above points Unsatisfactory - below 8.5 points
You can ask you teacher for the copy of the correct answers.
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Answer Sheet
Name: _________________________ Date: _______________
Choose
1. ____
2. _____
Matching
1. _______
2. _______
3. ______
4. ________
5. ________
6. _______
7. _______
8. _______
9. ________
10. ___________
11. _____________
12. ___________
13. ___________
Score = ___________
Rating: ____________
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Information Sheet-4 Applying Corrosion protection measure
4.1 Introduction to corrosion
Corrosion is a deterioration of something due to reacting with its environment. In very
simple terms, the metal from the pipe simply dissolves because of a reaction to the water
or to other environmental factors.
Pipeline breaks caused by corrosion or excessive stress on the pipes because of cases
such as soil subsidence, hydraulic pressures or freezing. Failure mode is one of effective
factors in determining the cause accidental, then it is recommended to investigate any
available break pipe. There are different forms of water pipeline failures:
Circular failure
Longitudinal failure
Break at joints and fittings
Breaks due to corrosion of corporation failure.
Piping Failures
A piping failure is often the first sign of a corrosion problem. Yet in many examples, signs
of an impending pipe failure have been evident for months or years, and gone ignored.
Failures can be minor (in the form of a pinhole leak) or catastrophic, with significant losses
due to water damage as well as the cost of pipe replacement.
4.2 protection and correction measure
Control measures are barriers necessary for preventing or reducing significant water
quality risks. They need to be developed, implemented and monitored for each hazardous
event identified as significant in the risk assessment. In the context of the distribution
system components, control measures are defined as those measures required in
drinking-water distribution systems that directly affect the safety or aesthetics of drinking-
water, either by preventing the occurrence of hazards or by inactivating, removing or
reducing them to acceptable levels. Control measures can include a wide range of
activities and processes. They can be:
preventive (and incorporated in design, planning and construction processes and renewal
of infrastructure);
treatment related (e.g. secondary disinfection);
technical (e.g. operational and maintenance procedures); and
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behavioral (e.g. customer awareness programs). Control measures must be defined
specifically and precisely for each significant hazardous event and adapted to the local
conditions.
Table 4. Cause and solution of pipe corrosion/problem and remedial measure
Hazardous event Control measure
System construction and repair
Contamination of distribution system during
new installations, including water meters,
pumps, valve or hydrant insertions
Code of practice
Construction standards and procedures
Disinfection practices prior to commissioning
Contamination during water main repair:
an open main (not capped) when in the repair
trench; could allow contamination, including
petroleum products, from pumps used for
dewatering
debris, soil or groundwater remaining in the
main after repairs and not removed during the
main recharge operation
Dewatering of trench prior to commencing
repairs
Prevention of contamination of pipe material
during storage, transport and repairs for
mains ≤150 mm
Flushing of water main – specify duration
based on length of the main and minimum
flow rate for mains >150 mm
Pipe cleaning (swabbing) and disinfection
after repair
Water quality testing (visual/turbidity) prior to
turning on the water main
Sediment suspension, sloughing of biofilms
causing customer complaints due to incorrect
valve operation (closed or opened) after
repairs
• Standard operating procedures for operation
of valves after repairs
Contamination from impurities in materials
used in construction and maintenance of
pipes, fittings and tanks (e.g. copper, iron,
lead, plasticizers, bituminous lining)
Approved product standards for materials in
contact with water
Approved product list
Compliance audits and materials checklist
Replacement of lead service lines
The use of inappropriate materials, including
use of metallic products that are incompatible
Approved product standards for materials in
contact with water
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with existing materials in the system, causing
corrosion
Approved product list
Compliance audits and materials checklist
System operation
Corrosion leading to loss of structural
integrity
• Approved product standards for materials in
contact with water
• Approved product list
• Leak detection programme
• Pipe and fittings replacement programme
Contamination from leaky water mains
in areas of low pressure or intermittent
water supply: ingress due to backflow
through leaky joints, air valves,
perforations
Maintain positive pressure, provide continuous
supply
Maintain minimum chlorine residuals in the
distribution network; if necessary, install
secondary/booster chlorination
Leak detection and repair programme
Pipe and fittings replacement programme
Design and construction specifications and
standards
Contamination from leaky sewer mains
in areas of low pressure or with
intermittent water supply: ingress due to
backflow through leaky joints, air valves,
perforations, leaking valves and
hydrants
Maintain positive pressure, provide continuous
supply
Maintain minimum chlorine residuals in the
distribution network; if necessary, install
secondary/booster chlorination
Leak detection and repair programme (sewer and
water main)
Pipe and fittings replacement programme (sewer
and water main)
Design and construction specifications and
standards
Design and construction standards to maintain
separation between water and sewer mains
Accumulation of biofilms, sediments and
particles in water mains due to low flow
Design standards to achieve self-cleaning pipe
velocities
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velocities in pipes and re suspension
during high-flow events
Operate valves and pumps to avoid rapid surges in
flows
Routine water main cleaning programme (in areas
where self-cleaning velocities cannot be achieved)
Maintain minimum chlorine residuals in the
distribution network; if necessary, install
secondary/booster chlorination
Re suspension of biofilms, sediments,
scales due to flow reversals
Operate valves and pumps to avoid flow reversals
where possible
Routine water main cleaning program
Maintain minimum chlorine residuals in the
distribution network; if necessary,
Survival of pathogens, growth of
opportunistic pathogens and nuisance
organisms in biofilms
Controls to prevent pathogen intrusion due to
ineffective treatment or distribution system integrity
breaches (e.g. treatment targets, main repair
procedures)
Maintain minimum chlorine residuals in the
distribution network; if necessary, install
secondary/booster chlorination
Replacement of chlorination with chloramination
Reducing or preventing biofilm growth through
proper maintenance
Storage tanks
Microbial contamination from entry of birds
and small animals or faeces through faults
and gaps in:
roofs or hatches
overflow pipes and inlet control valves from
upstream sources
air vents
Reservoir inspection and maintenance
programme, including repair of faults/gaps
Disinfect tank after repairs
Maintain minimum chlorine residuals in the
distribution network; if necessary, install
secondary/booster chlorination
Design and construction standards
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4.2. Preventing corrosion
Corrosion can be caused by a range of factors, which vary depending on the design and
construction of the distribution system. Operating procedures should identify key factors
associated with individual systems and establish operating criteria to prevent corrosion.
4.2.1. Pipeline Corrosion Protection Methods
Protection & Cleaning. When thinking about corrosion protection methods, cleaning
and protection should be at the top of the list
Cathodic Protection. This method of dealing with corrosion uses an electrical current.
Corrosion Inhibitors.
Coatings and Linings.
4.3. Repair of water main breaks
Water main breaks and leaks represent significant risks of contamination. Unlike
installation of new mains, repairs are normally undertaken in wet environments with limited
control of soil in the vicinity of the break, particularly in the early stages of detection and
excavation. Contamination can be introduced before repair, from soil and water in
trenches dug to effect repairs, from equipment and replacement pipes, fittings and
materials and from incomplete repairs.
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Self-Check -4 Written Test
Directions: Answer all the questions listed below. Use the Answer sheet provided in the next
page:
I.choose the best answer for the following question (2pts each)
1. ______is a deterioration of pipe due to reacting with its environment
A. Corrosion B. Default C. Problem D. Leak
2. Which one of the following is the solution when there is a problem occurs due to Corrosion
which leads to loss of structural integrity
A. Approved product standards for materials in contact with water B. Approved product list
C. Leak detection, Pipe and fittings replacement D. All F. none
3. Which one of the following is not Pipeline Corrosion Protection Methods?
A. Protection & Cleaning B. Cathode Protection C. Corrosion Inhibitors.
B. Coatings and Linings. D. All F. None
4. Which one of the following activities takes place for protection and correction measure
corrosion?
A. preventive (and incorporated in design, planning and construction processes and renewal
of infrastructure);
B. treatment related (e.g. secondary disinfection);
C. technical (e.g. operational and maintenance procedures); and
D. behavioral (e.g. customer awareness)
E. All F. None
5. Which one of the following is the solution of Contamination from leaky sewer mains in
areas of low pressure or with intermittent water supply
A. Maintain positive pressure, provide continuous supply
B. Maintain minimum chlorine residuals in the distribution network;
C. Leak detection and repair (sewer and water main)
D. Pipe and fittings replacement (sewer and water main)
E. Use without Design and construction specifications and standards
Note: Satisfactory rating – 5 and above points Unsatisfactory - below 5 points
You can ask you teacher for the copy of the correct answers.
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Answer Sheet
Name: _________________________ Date: _______________
Choose
1. ________
2. ________
3. ________
4. ________
5. ________
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Operation Sheet 1 Operating cast iron pipe Tapping
Activity 1. Cast iron pipe tapping procedure
1. Select appropriate PPE
2. Select appropriate tools and equipment
3. Dig to expose the pipe at the point where the tapis to be made. Dig as close to the top
of the water main as possible.
4. Clean all dirt and rust off the pipe at that point.
5. Place the gasket of the water-main self-tapping machine on the pipe, and set the
Saddle of the machine on the gasket.
6. Wrap the chain around the pipe, and tighten it to clamp the water main self-tapping
Machine to the pipe.
7. Remove the cap from the cylinder of the machine, and place the combination drill and
Tap in the boring bar.
8. Reassemble the machine by putting the boring bar through the cylinder and tightening
the cap.
9. Open the flap valve between the compartments.
10. Start drilling the hole by applying pressure at the feed yoke and turning the ratchet
handle until the drill enters the main.
11. When the tap starts threading the hole, back off the feed yoke to prevent stripping
the threads.
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12. Continue to turn the boring bar until the ratchet handle can no longer be turned without
extra force.
13. Remove the tap from the hole by reversing the ratchet. Then, back the boring bar out
by turning it counterclockwise.
14. Close the flap valve between the upper and lower compartments.
15. Drain the water from the cylinder through the bypass.
16. Remove the cap and drill tool. Place a corporation stop in the boring bar, ensuring
that the stop is closed.
17. Repeat steps 6 and 7.
18. Turn the ratchet handle to thread the corporation stop into the pipe.
19. Repeat step 13.
20. Remove the cap from the cylinder, and unbolt the boring bar from the corporation
stop.
21. Remove the lower chamber from the pipe.
22. Inspect for leaks.
23. If the corporation stop leaks, tighten it with a suitable wrench.
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Operation Sheet 1 Operating Saddle Tapping
Activity 2.
1. Verify the tap will be in an appropriate location.
2. Verify the saddle closely conforms to the pipe. There should be no gaps or high/low
spots on the pipe.
3. Attach the drilling machine to the pipe according to the manufacturer’s instructions. This
generally involves:
Attach the saddle to the main, tightening each side in turn until tightened with the same
amount of torque, ensuring the saddle remains level on the pipe.
Verify the saddle is level on the pipe. See Figure 14 for illustration.
Verify the pipe is not deformed due to over tightening.
4. Attach the correct size shell cutter or comparable tapping cutter to the drilling machine.
5. Lightly lubricate the outside of the cutter.
6. Using steady even pressure, drill the hole in the pipe. After each cut, remove the coupon
and chips from the cutter. Examine the PVC coupon - a smooth edge means a good cut
was made.
7. Verify that the tap is of the correct size, and is in good condition.
8. Attach the tap to the tapping machine and lubricate.
9. Using steady even pressure, tap the hole in the pipe. After each tapping operation,
remove the tap and clear the chips out of the new threads and cutter before inserting the
corp.
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Name: _____________________________ Date: ________________
Time started: ________________________ Time finished: ________________
Instructions: Given necessary templates, tools and materials you are required to
perform the following tasks within 6hr hour.
Task1. Operate for cast iron pipe Tapping
Task 2. Operate for saddle Tapping
LAP Test Practical Demonstration
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Instruction Sheet Learning Guide #- 27
This learning guide is developed to provide you the necessary information regarding the
following content coverage and topics –
Coordinating Installation of conduits with road and path construction.
Installing Conduits according to specifications, drawings and organizational requirements.
This guide will also assist you to attain the learning outcome stated in the cover page.
Specifically, upon completion of this Learning Guide, you will be able to –
Coordinate Installation of conduits with road and path construction.
Install Conduits according to specifications, drawings and organizational requirements.
Learning Instructions:
1. Read the specific objectives of this Learning Guide.
2. Follow the instructions described below 3 to 6.
3. Read the information written in the information “Sheet and Sheet 2, from page (76 and 79)
respectively and Accomplish the “Self-check 1 and Self-check 2 in page 78 and 82
respectively.
4. If you earned a satisfactory evaluation proceed to “Operation Sheet 1” in page 83
5. Then accomplish LAP Tests,”1,2, in page 84. (if you are ready). Request your teacher to
evaluate your performance and outputs. ensure you have a formative assessment and get a
satisfactory result;
6. Then proceed to the next LG
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Information Sheet-1 Coordinating Installation of conduits with road and
path construction
1.1. Introduction to duct and conduit
Transportation, communications and energy networks are growing in complexity. Such
networks include highways, railways and waterways at the surface; subways, pipelines and
cables below the surface; communication lines and electrical lines above the surface; and
wireless communications systems.
Utilities have various degrees of authority to install their lines and facilities on the right-of-way
of public roads. Like road authorities, their rights depend upon federal or provincial laws and
regulations, which differ between provinces. Utilities also depend upon local laws and
ordinances. laying of water pipes of large diameter along roads and/or slopes may be
necessary. In such case, the pipes shall be designed according to the requirements
stipulated laying Practice’ particularly the following aspects: -
Pipe size and pipe route requirements;
Pipe material requirements;
Installation requirements, e.g. trench excavation requirements, safety of road works, pipe
laying, thrust blocks and cathodic protection of water mains etc.; and
Repair, rehabilitation, operation and maintenance requirements, e.g. emergency repairs, leak
detection, draining of water mains and methods of water mains rehabilitation etc.
duct is a pipe, tube or canal which carries air or liquid from one place to another
while conduit is a pipe or channel for conveying water
Gray conduit is not rated for pressure pipe applications and may not be suitable for
potable water use. Stabilizers and other ingredients used in conduit PVC may be
toxic; conduit PVC is not held to the same drinking water standards as NSF marked pipe and
should not be used in potable water systems
The primary purpose of a road drainage system is to remove the water from the road and its
surroundings.
“Runoff” covers the water flowing from the surface of the pavement via road shoulders and
inner slopes to the ditches. Joining Methods Introduction Conduit can be joined by a variety
of thermal and mechanical methods.
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Figure 1. Conduit pipe
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Self-Check -1
Written Test
Directions: choose the best answer all the questions listed below. Use the Answer sheet
provided in the next page
I. Choose the best answer for the following question(4pts)
2. The purpose of conduit to install under road path
A. To protect the pipe form damage
B. To remove excess water under road
C. To protect different utilities
D. All
Note: Satisfactory rating –2 and above points Unsatisfactory - below 2 points
You can ask you teacher for the copy of the correct answers.
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Answer Sheet
Name: _________________________ Date: _______________
Choose
1. -----------
2-----------
3-----------
Score = ___________
Rating: ____________
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Information Sheet-2 Installing Conduits
2.1. Introduction to install conduit
Conduit, channel or pipe for conveying water or other fluid or for carrying out certain other
purposes, such as protecting electric cables. In water-supply systems the term is usually
reserved for covered or closed sections of aqueduct, especially those that transport water
under pressure.
2.2 PVC & CPVC Pipe Installation & Cementing process
1. Read the manufacturer's instructions for using the gluing products, primers, cements, and
joint assembly, including safety warnings and set and cure times vs. site conditions.
I know that you think instructions are just something to kneel on to get less mud on your
knees, but it's easier and cheaper to follow the instructions than to have to come back to the
job to clean up a burst pipe leak.
o Keep the lid on the container of solvent when you are not actively using it.
If you leave the solvent cement can open unnecessarily the volatiles will evaporate,
thickening the solvent and changing its properties, possibly making it "stringy" and nearly
impossible to use.
o Do not use old, thickened, dried, stringy solvent cements.
o Watch out: do not work in confined spaces nor near open flames or non-flame-proof
electrical equipment as you risk a fire or explosion -
2. Cut the pipe to proper length, square the pipe ends, chamfer the end (we use a small rasp
file), and clean the pipe end of dirt, water, snow, ice.
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"Chamfer" means that you use your file or knife or other tool to remove the burr left by
sawing the pipe, leaving a slightly-beveled edge on both the inside and outside of the pipe. I
take care to remove the plastic fragments produced by cleaning the burr off the pipe end so
that those don't contaminate and ruin the glue joint.
3. Dry-fit check that the pipe and fitting indeed fit together. The pipe needs to slide easily at
least 1/3 the way into the fitting before you've applied the glue.
It will slide all the way in when lubricated by the adhesive. If the pipe slides all the way in to
the stop when dry, it should be snug. If the pipe is loose or wobbly in the fitting the joint will
be a poor one likely to leak.
4. Use the right glue applicator: the size of your glue applicator should be at least 1/2 the size
of the pipe's inside diameter. For larger pipe diameters where this advice would be nuts,
you'll need to use a roller or a natural bristle brush to apply the flue.
5. Apply the PVC/CPVC Primer: clean the pipe and fitting before gluing by using a listed
primer. Only use a primer that is itself clean and clear. If it's contaminated the joint may leak
after assembly.
Watch out: do not use primer on ABS pipe and fittings.
6. Apply the PVC/CPVC Cement to the pipe: The primer will dry very quickly. Now, before
you've gotten dirt or crud in the joint, apply a liberal coating of cement to the outside of the
end of the plastic pipe to a depth that will match that of the receiving socket.
Watch out: do not leave un-coated with cement any area of the pipe that will be inside the
receiving socket or your joint will be poor and may fail or leak.
7. Apply the PVC/CPVC Cement to the fitting: apply a thin coating of cement to the inside of
the fitting you're about to push onto the pipe. As with the pipe, don't leave any voids of un-
coated surface inside the fitting.
8. Apply a second coat of PVC/CPVC cement to the pipe.
o Assemble the coated parts quickly - before they have dried. Push the pipe into the fitting
until bottoms.
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Watch out: The cement must be fluid. If the cement has dried on either fitting do not try to
assemble the joint or you'll be very sorry as the pipe won't seat fully in the joint, the joint will
be poor, and you'll find yourself having to start over with a new section of both pipe and a
new fitting. Instead, if the pipe and joint are not obviously wet with cement, re-coat them.
9. Hold the cemented parts in place for at least 30 seconds. Don't move or you'll be sorry. At
colder temperatures hold the joint longer, maybe a minute or more.
10. Wipe off excess glue around the outside of the plastic pipe joint
11. Allow the joint to set before moving it. See the set and cure times discussed in this article.
A general rule of thumb for temperatures over 60F and pipes under 3" in diameter is to allow
15 minutes for set time and 2 hours for initial cure time before pressure testing.
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Self-Check -2 Written Test
Directions: choose the best answer all the questions listed below. Use the Answer sheet
provided in the next page
1. Writ the purpose of Install conduit for water service pipes
2. define the word conduit
3. What is the difference between conduit and duct?
Note: Satisfactory rating – 6 and above points Unsatisfactory - below 6points
You can ask you teacher for the copy of the correct answers.
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Answer Sheet
Name: _________________________ Date: _______________
Choose
1.___
2.______
3._______
Score = ___________
Rating: ____________
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Operation Sheet 1
Performing for Conduit pipe Installation & Cementing
procedure
Conduit pipe installation procedure
1. Select appropriate PPE
2. Select appropriate tools and equipment
3. Read the manufacturer's instructions
4. Cut the pipe to proper length
5. Dry-fit checks that the pipe and fitting indeed fit together.
6. Use the right glue applicator:
7. Apply the PVC/CPVC Primer.
8. Apply the PVC/CPVC Cement to the pipe:
9. Apply the PVC/CPVC Cement to the fitting:
10. Apply a second coat of PVC/CPVC cement to the pipe.
11. Assemble the coated parts quickly
12. Hold the cemented parts in place for at least 30 seconds.
13. Wipe off excess glue around the outside of the plastic pipe joint
14. Allow the joint to set before moving it.
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Name: _____________________________ Date: ________________
Time started: ________________________ Time finished: ________________
Instructions: Given necessary templates, tools and materials you are required to perform
the following tasks within 3 hour.
Task1. Perform Conduit pipe Installation & Cementing procedure
LAP Test Practical Demonstration
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Instruction Sheet Learning Guide #- 28
This learning guide is developed to provide you the necessary information regarding the
following content coverage and topics –
Measuring and cutting of Pipes Copper
Preparing pipe ends and made joints Threaded
Setting- out Configuration of pipes and fittings
Recognizing Joining faults or malfunctions
Selecting place, bedding and backfill material.
This guide will also assist you to attain the learning outcome stated in the cover page.
Specifically, upon completion of this Learning Guide, you will be able to
Measure and cut of Pipes
Prepare pipe ends and made joints Threaded
Set out Configuration of pipes and fittings
Recognize Joining faults or malfunctions
Select place, bedding and backfill material
Learning instruction
1. Read the specific objectives of this Learning Guide.
2. Follow the instructions described below 3 to 6.
3. Read the information written in the information “Sheet1 , Sheet 2,sheet 3,sheet sheet 4, and
sheet 5” from page (85, 115,138,144and 146)and Accomplish the “Self-check 1,Self-check
2,self-check 3, Self-check 4 and Self-check 5,” in page -112,133,142,142,145 and 150)
respectively.
4. If you earned a satisfactory evaluation proceed to “Operation Sheet 1”, operation sheet 2,
operation sheet 3 and operation sheet 4 in page ( 152,153,158 and 157)
5. Then accomplish LAP Tests,” 166, in page. if you are ready). Request your teacher to
evaluate your performance and outputs. ensure you have a formative assessment and get a
satisfactory result;
6. Then proceed to the next LG
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Information Sheet-1 Measuring and cutting of Pipes Copper
1.1.Introduction to pipes and pipe fittings types
A pipe can be defined as a tube made of metal, plastic, wood, concrete or
fiberglass. Pipes are used to carry liquids, gases, slurries, or fine particles.
A piping system is generally considered to include the complete interconnection of pipes,
including in-line components such as pipe fittings and flanges.
Common metals include:
Aluminum - lightweight and corrosion resistant. Aluminum is commonly used for plumbing
and is the preferred fitting material for aluminum piping. By itself, aluminum has low tensile
strength and is used when high corrosion resistance is needed. It is alloyed with zinc,
copper, silicon, manganese, and/or other metals to improve its strength and hardness.
Brass - strong, durable, and corrosion resistant, with high temperature ductility and good
conductivity. Brass is an alloy of copper and zinc, and is commonly used for smaller
compression and threaded pipe fittings in industry because of its machinability and its
excellent performance properties
Cast iron - strong and highly abrasion resistant. Cast iron fittings and pipes are used
primarily in building construction for sanitary, storm drain, waste, and vent piping
applications because of their resistance to abrasive materials like sand, gravel, solid
wastes, and debris.
Copper - extremely corrosion resistant with excellent conductivity. Copper fittings are
important for many plumbing and heating applications, and are commonly used for
residential water supply lines.
Steel - durable and strong, with a high resistance to heat. Steel is an alloy of iron and
carbon; it is commonly alloyed with other metals to improve its corrosion resistance and
durability. It is used in both commercial and industrial applications for carrying water,
flammable gases, and other fluids. Galvanized steel is coated with zinc for rust and
chemical corrosion resistance. Carbon steel is alloyed with higher levels of carbon for
increased durability and strength.
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Stainless steel - relatively strong with excellent chemical and corrosion resistance.
Stainless steel is an alloy of steel that contains over 10.5% chromium, providing
excellent corrosion resistance for sanitary applications and those dealing with aggressive
fluids and materials.
Common plastics include:
PVC (poly-vinyl-chloride) - a common plastic for pipe fittings. PVC is a rigid plastic
which can come in a variety of pressure ratings. Fittings are connected via threads or
solvent welding (glue). Standard applications include cold water supply and drainage.
ABS (acrylonitrile butadiene styrene) - black and rigid plastic with similar properties
and applications to PVC, but typically more economical.
Polyethylene (PE) - the most preferred plastic for hot and cold temperature applications.
PE is grey or black, semi-flexible plastic. Fittings are used commonly for supply lines to
sprinkler systems and underground geothermal heating loops.
Polypropylene (PP) - thermoplastic material that exhibits excellent cold flow, bi-axial
strength, and yield elongation properties. It is similar to PVC, but can be used in exposed
applications because of its resistance to UV, weathering, and ozone.
Nylon - plastic with high chemical and corrosion resistance. It is the preferred plastic for
applications involving flammable fluids, chemical solvents, and potable water
1.1.1. Copper Pipe
Use compression connections to join this type of pipe.
Common sizes of pipe diameter are 3/8”, 1/2” and 3/4”.
Larger sizes may be used for DWV (drain-waste-vent) applications.
Type K is heaviest, used in municipal, commercial, residential and underground
installation; Type L is medium weight and is the most commonly used in residential water
lines; Type M is hard and thin.
Figure 1. Copper pipe
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1.1.2. PVC Pipe
PVC (polyvinyl chloride) is used for carrying cold water, irrigation, use as conduit and for
DWV (drain-waste-vent) projects.
Use compression or solvent weld connections to join this type of pipe.
Available in diameter sizes ranging from 1/2” to 2”.
Rated by thickness and strength.
Figure 1.2. PVC pipe
1.1.3. CPVC Pipe
CPVC (chlorinated polyvinyl chloride), is used for both hot and cold water supply or
chemical distribution systems.
Use compression or solvent weld connections to join this type of pipe.
Requires special solvent cement that is different from cement used for other types of
plastic pipes.
Figure 1.3. CPVC pipe
1.1.4. Galvanized Pipe
Used primarily for carrying water or waste. Do not use for gas or steam applications.
Use threaded connections to join this type of pipe.
Measured using the I.D. (inside diameter).
Common water sizes are 3/8”, 1/2”, 3/4” and 1”. Common waste sizes are 1-1/2”, 2” and
3.
Figure 1.4. Galvanized pipe
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1.1.5. Black Iron Pipe
Used for carrying steam or gas.
Used only with black iron pipe fittings, not galvanized fittings.
Not treated for rust resistance.
Use threaded connections for joining this pipe.
Measured using the I.D. (inside diameter).
Figure 1.5. Black iron pipe
1.1.6. PEX Pipe
PEX, which stands for cross linked polyethylene, is used for carrying hot and cold water.
Do not weld with solvents. Join with heat fusion, flare, crimp ring or compression fittings.
Chief advantage is its flexibility and strength. It can make turns around corners without
couplings.
Excellent chemical resistance to acids and alkalis, but do not use for fuel oil, gasoline or
kerosene systems.
In a PEX plumbing system, a separate line is run from the main water supply to each
fixture in a setup much like a circuit breaker box.
Figure 1.6. PEX pipe
1.1.7. ABS/DWV Pipe
Commonly used for DWV (drain-waste-vent) applications or for underground electrical
conduits.
Use compression or solvent weld connections to join this type of pipe.
Made from a thermoplastic resin. Lightweight and easier to use than metal pipe.
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Available as either solid wall or cellular yrenecore construction.
ABS stands for Acrylonitrile Butadiene St.
Figure 1.7 ABS/DWV pipe
1.1.8. Black Poly Pipe
Used for carrying low-pressure cold water. Common applications include golf course
sprinklers, underground conduits or to carry corrosive liquids and gases.
Good chemical and crush resistance.
Lightweight enough to cut with an ordinary knife or a fine-toothed hacksaw blade.
Figure 1.8. Black poly pipe
1.1.9. HDP pipe
Figure 1.9 HDP Pipe
1.1.10. Water meter
Water meters are used to measure the volume of water used by residential and
commercial buildings that are supplied with water by a public water supply system. Water
meters can also be used at the water source, well, or throughout a water system to
Determine flow through a particular portion of the system. In most of the world water
meters measure flow in cubic meters (m3) or liters but in the USA and some other
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countries water meters are calibrated in cubic feet (ft.3) or US gallons on a mechanical or
electronic register. Some electronic meter registers can display rate-of-flow in addition to
total usage.
There are several types of water meters in common use. The choice depends on the
flow measurement method, the type of end-user, the required flow rates, and accuracy
requirements.Characteristics of pipe materials.
A pipe is a tubular section or hollow cylinder, usually but not necessarily of circular
cross-section, used mainly to convey substances which can flow — liquids and gases
(fluids), slurries, powders and masses of small solids.
What is the most common pipe material?
the most commonly used materials for drinking-water supply piping are galvanized steel
or iron, copper, polybutylene, un-plasticized polyvinylchloride (PVC), chlorinated
polyvinylchloride (CPVC) and polyethylene (PE)
1.1.11. Characteristics of good water pipes
Having problems on choosing what pipes to use for your waterline? Consider these tips
as your guide in deciding.
Pipes should be suitable for expected pressure, flow and temperature of the water.
Pipes must not contaminate water.
Pipes should be compatible with the water supply, to minimize the potential for
electrolytic corrosion
If used underground, pipes should be suitable for the ground conditions to prevent
exterior corrosion.
Pipes should be appropriate for the local climate if to be used outdoors.
Pipes should be able to withstand UV effects if used outdoors
Property of different type of pipe
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Table 1. Different pipe properties
Bad design of the pipes and structures may cause severe corrosion even in materials that
are highly resistant. Some of the important design considerations include
selection of appropriate flow velocity
selection of appropriate metal thickness
reduction of mechanical stresses
avoiding sharp bends and elbows
avoiding grounding of electrical circuits to the system
providing easy access to the structure for periodic inspection, maintenance and
replacement of damaged parts
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1.3. Types of Fittings
1.3.1. Caps & Plugs
A cap is closed on one end with female threads or no threads for a solvent weld
connection.
Figure 1.11 cap
A plug is closed on one end with male threads or no threads for a solvent weld
connection.
Both are used to seal a run of pipe.
Figure 1.12 plug
A cleanout plug can be added to a tee at the base of a vertical drain pipe. The plug is
threaded for easy access to the drain. The threaded fitting for the plug can be added on,
or some tee fittings have the threaded connection built-in.
Figure1.13 plug
1.3.2. Coupling
Connects two lengths of pipe.
Has female thread on both ends (for galvanized pipe) or no threads (for copper, PVC
and other solvent-welded pipe).
Figure1.14 coupling
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1.3.3. A reducer
Coupling joins two different sizes of pipe.
An adapter coupling joins two different types of connection types, such as threaded and
solvent weld.
Figure1.15 reducer
A repair coupling, or mender coupling, has no center stop so two lengths of pipe can b
fastened together. Use on unthreaded lengths of pipe.
Figure1.16 outer thread reducer
1.3.4. Elbow
Changes the direction of the pipe, usually at a 45°, 90° or 22-1/2° angle.
Most common are elbows with female threads or solvent welds on both ends.
A street elbow has a female end on one end and a male end on the other. Also available
for solvent welded products.
A sweep is a type of elbow that has a longer curve for a more gradual bend. Available in
long or short versions.
Reducing elbows change the size of the pipe
Figure1.17 elbow
1.3.5. Tee
Three female openings in a T shape.
A straight tee has the same size openings.
A reducing tee has two openings of the same size and one of a different size.
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A sanitary tee is used in waste lines. They have a curved branch designed for a cleanout
plug and are designed to prevent obstruction of waste.
A cross has four female openings of equal size.
A cleanout tee has a threaded opening to be used in conjunction with a threaded plug for
a cleanout opening on a drain pipe.
A wye bend has three female openings. Two are straight in a line; the third is at a 45°
angle.
Figure1.18 Tee figure 1.19 Y Tee figure 1.20 cross tee
1.3.6. Nipple
Any length of pipe that is less than 12” and used to extend a run of pipe.
Usually available in increments of 1”, from “close” (the shortest length, where threads
almost touch) to 12”.
Longer lengths of pipe are considered “cut lengths” and are available in 24” increments.
Figure 1.21 nipple
1.3.7. Union
A three-part fitting that connects any standard size pipe where it may be necessary to
disconnect later, such as on a water heater.
Connects to male threaded ends.
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Figure 1.22 union
1.3.8. Saddle Tee
Joins a smaller drainpipe to a larger one, such as a 1-1/2” pipe to a 3” pipe.
Used when installing a drain on existing plumbing. Saves the labor of cutting and rejoining
the main pipe.
Some types are made for joining a PVC pipe to a cast iron drain.
Figure1.23 saddle tee
1.3.9. Gasket
They are mechanical seals, generally ring-shaped type and fitted for sealing flange joints.
A flange joint is a plate or ring to form a rim at the end of a pipe when fastened to the pipe.
Gaskets are made as per by construction, materials and features. Important gaskets used
are nonmetallic, spiral-wound and ring-joint type
Figure1.24 Gasket
1.3.10. Trap
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It is a fitting in a P, U, S or J-shaped type. Traps are fitted near a plumbing fixture. The
trap bend is fitted to prevent sewer gases from entering the building. If the gases are
inserted back into home, then it could lead to people inhaling foul smell, which could
cause illnesses.
Figure 1.25. different type of trap
1.4. Valves
1.4.1. Gate Valve
Used to completely shut off or open a waterway. Does not control the volume of flow.
Uses a sliding wedge to move across the waterway, in either a rising or non-rising action.
In some models, either opening of a gate valve may face the pressure side of the line,
while in others, an arrow indicates the direction of water flow.
Because they allow the complete passage of water, use on supply lines that are in
constant use.
Figure 1.26 gate valve
1.4.2. Ball Valve
Used to completely shut off or open flow, or to regulate flow.
Uses a large lever to turn a ball that closes or opens valve with one quick quarter turn.
Are the standard for natural and LP gas, replacing the older plug valves that were
traditionally used as gas valves.
Available in either metal or plastic, threaded or non-threaded types.
Ball valves with double-stem seals provide greater durability.
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Figure1.27 ball valve
1.4.3. Globe Valve
Used to control volume of flow.
Has a hand wheel that turns a disc that opens or closes the valve.
Used when a valve must be opened and closed frequently under high water pressure.
Should not be used for occasional shut-off purposes in water supply lines.
Easy to repair.
One type is an angle valve, which has ports at right angles. It allows for greater water
passage than a globe valve.
Figure 1.28 glove valve
1.4.4. Pressure Relief Valve
Used to protect water heaters or hot water storage tanks.
When the water pressure reaches a dangerous level, the valve opens and discharges
water. Cold water then flows into the tank and stabilizes the water pressure.
Figure 1.29 pressure relief valve
1.4.5. Check Valve
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Operates automatically, permitting flow in one direction only.
Used to prevent water pumped to an overhead tank from flowing back when the pump
stops.
Sometimes combined with a throttling or shut-off valve. Some communities require a
check valve in cold water lines between the water heater and meter.
Figure 1.30check valve
1.4.6. Ferrule
It is used for connecting a service pipe to the water main. It is usually made of non-ferrous
metal and screwed to the main pipe
Figure 1.32. Ferrule
1.4.7. Foot valve
It is a valve used in the pump. It is also called check valve, as it makes sure that the pump
is ready to use. If the pump is off, then the foot valve keeps enough fluid in the pump to
ensure that it can start again. In a well, the foot valve will be between the water surface
and the pump.
Figure 1.33foot valve
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1.4.8. Float valve
It is used for stopping water when the water tank or flush toilet is filled, so that it stops
overflowing. When the water level rises, the float also rises; once it rises to a pre-set level,
the water level forces the lever to close the valve and stops the water flow. A float valve is
a fitting used for filling water tanks as well as flush toilets
Figure 1.35 float valve
Figure 1.31 pipe and pipe fitting assembling
1.5. work-related calculations
For the installation of service pipes some minor calculation should be made
1.5.1. Volume of excavation
Suppose the length of the service pipe is 30m, the depth of excavation is 20cm assuming
the width of the trench 20cm the volume of excavation can be calculated as
V=L*W*H
V=30*0.2*0.2=4.8m3
1.5.2. Volume of backfill
The volume of backfill can be calculated as
Volume of backfill=Volume of excavation*volume of pipe installed
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But related to the volume of excavation the volume of pipe installed is negligible so mostly
volume of backfill = volume of excavation -volume of soil caraway
1.6 Measuring length of pipe and pipe fittings
The measurement for a length of pipe required for installation includes the amount of pipe
engagement and the dimension of the fitting. So, engagement, fitting dimensions, and pipe
length is important to know.
Engagement for cast-iron soil pipe (single-hub). Different sizes of pipes require different
amounts of engagement. A pipe engagement occurs when the spigot end of one pipe fits into
the hub end of another pipe. A fitting engagement occurs when the end of a fitting fits into the
hub end of a pipe. Always measure the distance inside the hub for a true pipe or fitting
engagement.
Figure 1.32 examples of pipe engagement
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1.5.3. Engagement for rigid plastic pipe (ABS and PVC).
Different sizes of pipes require different amounts of engagement. Engagement occurs
when the end of a pipe fits into the collar of a fitting. Always measure the distance inside
the collar for a true fitting engagement.
Figure 1.33 engagements between fittings with pipe
1.5.4. Engagement for galvanized steel pipe.
Different sizes of pipe require different amounts of engagement. Engagement occurs
when the threaded end of a pipe fits into the collar of a fitting. Always measure the
distance inside the collar for a true fitting engagement
Figure 1.34 galvanized steel pipe engagement
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1.5.5. Engagement for rigid copper tubing (DWV).
Different sizes of tubing require different amounts of engagement. Engagement occurs
when the end of the tubing fits into the collar of a fitting. Always measure the distance
inside the collar for a true fitting engagement
Figure 1.35 rigid copper tubing engagement
1.6. Fitting Dimension
The fitting dimension is also needed when determining the amount of pipe required for
an installation. The fitting dimensions for all types of waste fittings are determined the
same way. A fitting dimension is the distance from the centre of the fitting to the end of
the fitting.
Figure 1.36 size of steel pipe with engagement
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1.6.1. End-to -center measurement
Figure 1.37 ends- to- center measurement of pipe
1.6.2. Centre-to –center
Figure 1.39 center-to-center measurement of pipe
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1.6.3. Face-to face
Figure 1.40 face to face/ed to end measurement of pipe
1.7. Determination of Amount of Pipe Required for Installation
1.7.1. Pipe-to-pipe. To figure the length of pipe required when using single-hub cast-iron pipe, use
the following steps. The example given in italics is from the illustration below.
Measure the end-to-end distance from the place where the new pipe will be installed (42
inches).
Add the amount of engagement (42 + 6 = 48).
Take a double-hub pipe and cut off the one end. The remaining piece should equal the total
(48 inches).
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Figure 1.41. Length of pipe without fitting
Example: end-to-end=42 inches, engagement=6 inches, length of pipe required=48
inches
1.7.2. Pipe-to-fitting. The method for figuring the length of pipe required for a pipe-to-fitting
connection is the same for all types of piping. Use the following steps. The example given
in italics is from the illustration below.
Measure the end-to-center distance from the place where the new pipe will be installed (60
inches).
Subtract the fitting dimension (60 - 6 = 54).
Add the amount of engagement (54 + 2½ = 56½).
Cut a pipe the length of the total (56½ inches)
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Figure 1.42 length pf pipe with one side of fitting (end-to-centre)
Example:
end-to-end
fitting dimension
engagement
length of pipe required
-
+
=
60 inches
6 inches
2½ inches
56½ inches
1.8.9. Center-to-center. The method for figuring the length of pipe required for a connection
between fittings is the same for all types of piping. Use the following steps. The example
given in italics is from the illustration below.
Measure the center-to-center distance from the place where the new pipe will be installed
(66 inches).
Subtract both fitting dimensions (66 - 5 - 5 = 56).
Add the amount of engagement for both fittings (56 + 2 + 2 = 60).
Cut a pipe the length of the total (60 inches).
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Figure 1.43 length of pipe with both side fitting (centre -to -centre)
Example:
center-to-center
both fitting dimension
engagement
length of pipe required
-
+
=
66 inches
10 inches
4 inches
60 inches
1.7.3. Measurement of Galvanized Steel Pipes
Before you cut any pipe, exact measurements must be taken. Most likely for measuring pipes
the tape rule is to be used. For marking out the use of scriber, pencil or soap stone is
common. An accepted overall tolerance for pipe installations is 2 mm plus and 2 mm minus
the demanded size. Below you can find some methods on how to measure properly.
Figure 1.44 measurement of steel pipe
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1 = Centre to face 2 = Engagement of thread 3 = Centre of fitting to end of pipe
measurement Pipe length are generally measured by one of the following methods: End of
pipe thread to centre of fitting
Figure 1.45 measurement of steel pipe from end to centre and centre to centre
1 = Centre of fitting to centre of fitting 2 = End of pipe to end of pipe An "end of pipe to centre
of fitting" measurement is made by tightening the first fitting on the threaded end of a pipe.
Then place the end of the rule exactly in the centre of t
Clamping Pipes to cut pipes they must be fixed to prevent them from rotating. The pictures
below show you some common holding devices.
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Figure 1.46 pipe vice
1.8. Cutting Galvanized Pipes
Actually, there are two common manual ways to cut galvanized steel pipes.
Using a hacksaw
Using a pipe cutter.
Manual Pipe Threading when using galvanized pipes for installations most likely both ends of
the pipe will have a thread. Since all pipe fitting are tapered with the internal (female) pipe
thread during manufacturing, the pipe fitter has to cut only the external thread.
Table1.1 Characteristics of Tapered Pipe Threads according to the ANSI and ISO Standard
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Remember, the installation of a pipe system should be done accurately. This means, that the
pipes should be free from any burr inside or outside
CUTTING PVC. The easiest way to cut smaller-diameter PVC pipe is with a PVC ratchet
cutter. For cutting larger diameter pipe, use a hacksaw.
How to Cut PVC Pipe
Tools Needed
PVC Pipe Cutter, or Hacksaw
Sandpaper
Tape measure
Pencil
Miter Box (optional)
Directions
1. Always cut the longest pieces first. That way, you’ll be able to use more of the pipe.
2. Mark the length to be cut with a pencil.
3. Cut with a standard PVC pipe cutter. The easiest to use is a simple ratchet-style cutter
available at most hardware stores.
4. Line up the pencil mark with the pipe cutter blade, then cut on the inside edge of your
mark.
Option: You can also cut the pipe with a hack saw. To make a straight cut, place the pipe into
a miter box. Wedge a piece of scrap wood between the pipe and the side of the miter box to
brace it securely. Then hold or fasten the miter box securely on a solid work surface. Cut on
the inside edge of your pencil mark.
When done, remove any burrs with a medium flat file or 80 to 100-grit sandpaper. Use a rat-
tail file or knife for the inside of the pipe, if needed.
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Caution: Be certain to wear a proper protective dust mask or respirator as you cut the pipe.
You don't want to breathe in the fine PVC dust particulates, which can be dangerous to your
health.
1.10 Hazardous during pipe Installation and excavation
When completing work on site pipe fitters are exposed to many new hazards as
1. Performing hot works in explosive atmospheres (i.e. solvent or dust laden
atmospheres)
2. Tying into live piping systems
3. Working at heights, off ladders or scaffolds
4. Working in confined spaces, trenches or excavations
5. Construction plant and equipment moving around site
6. Working close by to suspended loads and lifting equipment
7. Being exposed to buried services and or electrical cables
8. Falls into trenches or excavations.
9. Tripping over equipment, debris and spoil.
10. Excavated material or other objects falling on workers.
11. Exposure to underground services or overhead electrical cables.
12. Unstable adjacent structures.
13. Mishandled or poorly placed materials
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Self-Check -1
Written Test
Directions: choose the best answer all the questions listed below. Use the Answer sheet
provided in the next page
I. Choose the best answer for the following question (3pts)
1. During the installation of pipe the dimension of pipe length measured from
A. Center to center
B. Center to end
C. End to end D. All
2. Which one of the following is not the type of pipe fitting?
A. Union
B. Nipple
C. Gate valve
D. Galvanized pipe
3. Which one of the following equipment used to tying or hold pipe during pipe cutting
process?
A. Pipe thread
B. Hacksaw
C. Pipe vice
D. Pipe wrench
4. From the given alternative one is not the purpose of measuring pipe length
A. To determine the amount of pipe
B. To determine the amount of pipe
C. To determine the size of pipe
D. To determine the size of engagement
E. All f. none
5. __________coupling joins two different sizes of pipe.
A. Nipple
B. Reducer
C. Gate valve
D. Elbow
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6. Which one of the following are not work-related calculations during service pipe installation?
A. Excavation volume of soil
B. Back filling volume of soil
C. Amount of resource (amount of pipe, fitting, lab our)
D. All E. None
7. Which one of the following is not types of pipe
A. Copper Pipe and PVC Pipe
B. CPVC Pipe and PEX Pipe
C. Galvanized Pipe and Black Iron Pipe
D. Gate valve and reducer
Matching column A with column B(1pts))
Note: Satisfactory rating – 10.5and above points Unsatisfactory - below 10.5
points
You can ask you teacher for the copy of the correct answers.
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Answer Sheet
Name: _________________________ Date: _______________
Choose
1. ____
2. ______
3. _______
4. _______
5. _______
6. _________
7. __________
Matching
1. _________
2. ___________
3. ____________
4. ____________
Score = ___________
Rating: ____________
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Information Sheet-2 Preparing pipe ends and made joints Threaded
2.1. Introduction to pipe ends
Edge preparation consists of removing material along edges of metal surfaces. You
must prepare edges for welding when parts and assemblies require certain strength. To
achieve full welding penetration, you must cut the edges of the metal. Edge preparation is
only possible for certain weld types. Pipe ends must be square cut. Always use a pipe band-
saw or automatic round-saw for cutting pipe.
2.2. Joining pipes and fittings
Pipes joining
Install water line pipe runs during the building construction. The following steps will make it
easier to rough-in pipe runs with fittings, support the pipe runs, and test the rough-in water
pipe system joints for leaks. The pipe runs consist of distribution lines, branch lines, and riser
lines which will service the fixtures or equipment.
Main Distribution Lines
Install this pipeline, with all fittings required for the branch lines, between or through the floor
joint from the meter stop. The pipe size will be the same as the water service line.
Branch Lines
From the fittings on the distribution line, install the branch pipelines between or through the
floor joist to those fixture points that the riser pipes will service.
Fixture Riser Lines
From the branch pipeline fittings, install fixture supply pipe risers by drilling holes through the
sole plate or floor. Set the risers with fittings to connect the water supply. Set the air chamber
to control the pipe noise.
Install Rough-In Water Lines
Drill a hole through the center of a joist. The hole cannot be larger than one quarter of the
depth of the joist. Center the hole between the top and bottom of the joist. For example, if
you are using a 2- by 8-inch joist, the hole cannot be any larger than 2 inches.
Distribution pipe can be joined in either of the following ways.
The type of joint used is mostly determined by the pipe material used, but also by other
requirements such as the ability to handle tension forces, toleration of small deflections and
ease of use in the field.
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2.2.1. Types of Joints
Gasket (most common)
Welded (typically steel)
Solvent Cement (PVC & ABS)
Heat Fused (HDPE & PE)
Flanged (most common joint geometry)
Mechanical Couplings (CMP)
Threaded joint
Brazed joint
Soldered joint
Grooved joint
Flanged joint
Compression joint
The most common types of joints are listed below and illustrated in Figure 2:
a. In spigot and socket (or bell and spigot) joints, one end of a pipe section (the bell) is
enlarged and provided with a rubber seal, while the other end (the spigot) is left unchanged.
To join two pipes, the spigot of one pipe is pushed into the bell of the other pipe to create a
watertight seal.
b. Butt fusion jointing is used to connect HDPE pipes: the ends of both pipes are heated and
then pressed together at a prescribed pressure to create a bond.
c. Electrofusion is an alternative jointing method for HDPE pipes that employs special collars
with built-in heating coils. The ends of the pipes are cleaned and their outer layers removed
using a special scraping tool to expose virgin material. The electrofusion collar is then placed
over the pipe ends and an electrical current applied to the heating coil. The heat melts the
material of the collar and pipe together.
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Figure 2. Common types of pipe joints: a) spigot and socket; b) butt welded; c) electrofusion;
d) flanged; e) welded; f) mechanical coupling.
Flanged joints consist of both pipes ending in flanges with holes allowing them to be bolted
together. A gasket is fitted between the two flanges to ensure a watertight seal.
Large diameter steel pipes may be joined by welding them together in the field. Quality
control is critical to ensure that welds are done properly.
Flexible mechanical couplings that compress sealing rings when their bolts are tightened.
These couplings can be used to join the same or different types of pipe with plain ends. It is
possible to leave a gap between the pipes being joined, which is useful in valve chambers or
pump stations where this gap allows components to be easily disassembled and
reassembled.
Threaded joint
When pipes are joined by screwing in threads which are provided in the pipe, it is called a
threaded joint. In this joint, one of the pipes has internal threads whereas the other pipe has
threads externally. The threads are also made in various pipes like PVC, CI pipes, copper
pipes and GI pipes, etc. Threaded joints are used from 6 mm diameter to 300 mm diameter
pipes
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Figure2.1. figure threaded joint
Brazed joint
When pipes are joined with the help of molten filler material at above 840°C, it is called
brazing. Brazing is done for connecting copper pipes or copper alloy pipes. Itis important to
note that the melting point of the parent material (pipe material) should be higher than the
filler
material. Brazed joints have less mechanical strength, and are preferred in case of moderate
temperatures
Figure 2.2brazed joint
Socket welded joint.
These are used when there is a high chance of leakage in the joints. Pipes are joined as
putting one into other and welded around the joint. Pipes having different diameters are
suitable for this type of a joint. Socket-welded joint gives good results as compared to other
joints.
Figure 2.3. Sockt welded joint
Soldered joints
Soldering and brazing are similar activities. In soldering, the filler material melts below
840oC. With the help of soldering, copper and copper alloy pipes are joined. During
soldering, flux or metal joining material is used to prevent oxidation due to the flame.
Soldered joints are suitable for low temperature areas and have low mechanical strength
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Figure 2.4. Brazed and soldered joint
Grooved joints
When two pipes are joined together by making grooves (narrow cuts or depression) at the
end of pipes with the help of sockets or couplings, such joints are
called grooved joints. Due to the ease of assembly of the grooved joints, the labour cost is
less. The piping system can be easily uninstalled and reinstalled
Frequently for maintenance These are mostly used for fire protection.
Figure 2.5. Grooved joint
Compression joints
These are applied to join the pipe without any preparations. The cost of installation of these
joints is very economical. The pipes having plain ends are joined by fixing fittings at their
ends, and such a joint is called a compression joint. The pipe ends are joined
with threaded fittings or couplings. Joints are placed properly to check the flow pressure,
otherwise, leakage may occur. These fittings are manufactured from different types of
material. Selection of fittings is done as per requirement
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Figure 2.6. compression joint
Push-fit (ring seal) jointing
1. Where plain end pipe is being used, ensure that the pipe is cut square to its axis and that
all burrs are removed.
2. Chamfer the end of the pipe to prevent the ring seal being damaged or displaced when the
pipe is inserted into the socket. Fittings with spigot ends are moulded with a chamfer during
manufacture.
3. Lubricate the spigot or ring seal with Polypipe silicone grease or aerosol lubricant.
4. Insert the pipe or fitting into the socket and then withdraw it by approx. 10mm to allow for
expansion of the pipework.
Solvent Weld Joints
Solvent cement jointing is a welding process and not a glueing process. If done correctly,
separation will not be possible after the curing period. Jointing of pressure pipe should not be
carried out on pipes and/or fittings if there is a rattle fit between dry pipes and/or fittings.
There should be an interference fit between the components before solvent cement is
applied. There are different solvents cements available for pressure applications and for non-
pressure applications. Be sure to use the correct cement and that it has not “dried out” prior
to use.
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Solvent cement jointing procedure
1. Prepare the pipe Before jointing, check
that the pipe has been cut square and all the
burrs are removed from the inside and
outside edge. Do not create a large chamfer
that will trap a pool of solvent cement.
Remove all dirt, swarf, and moisture from
spigot and socket.
2. Witness mark the pipe
It is essential to be able to determine when
the spigot is fully home in the socket. Mark
the spigot with a pencil line (‘witness mark’)
at a distance equal to the internal depth of
the socket.
3. ‘Dry fit’ the joint
‘Dry fit’ the spigot into the socket, check the
pipe for proper alignment. Any adjustments
for the correct fit can be made now, not later.
For pressure pipes, the spigot should
interfere in the socket before it is fully
inserted to the pencil line.
4. Prepare with priming fluid
Dry, degrease and prime the spigot and
socket with a lint-free cloth (natural fibres)
dampened with Vinidex priming fluid
5. Brush selection
The brush should be large enough to apply
the solvent cement to the joint in a maximum
of 30 seconds. Approximately one third the
pipe diameter is a good guide. Do not use
the brush attached to the lid for pipes over
Table of recommended brush selection
Diameter of pipe Recommended size of
brush
Mm mm
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100mm in diameter. Decanting is not
advisable, and excess should never be
returned to the can. For large diameter
pipes, it may be necessary to decant to an
open larger vessel for a large brush to be
used, in this case decant for one joint at a
time.
15, 20, 25, 32, 40,
50 use brush supplied
65, 80 25
100, 125 38
150 50
200 63
225, 250 75
300, 375 100
6. Apply solvent cement
Using a suitably sized brush, apply a thin
even coat of solvent cement to the internal
surface of the socket first. Solvents will
evaporate faster from the exposed spigot
than from the socket. Special care should be
taken to ensure that excess solvent cement
isn’t built up at the back of the socket (pools
of solvent will continue to attack the PVC
and weaken the pipe). Then apply a heavier,
even coat of solvent cement up to the
witness mark on the spigot. Ensure the
entire surface is covered. A ‘dry’ patch will
not develop a proper bond, even if the
mating surface is covered. An unlubricated
patch may also make it difficult to obtain full
insertion.
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7. Inserting the spigot
Make the joint immediately, in a single
movement. Do not stop halfway, since the
bond will start to set immediately and it will
be almost impossible to insert further. It will
aid distribution of the solvent cement to twist
the spigot into the socket so that it rotates
about a 1/4 turn whilst (not after) inserting,
but where this cannot be done, particular
attention should be paid to uniform solvent
application.
8. Push the spigot home
The spigot must be fully homed to the full
depth of the socket. The final 10% of spigot
penetration is vital to the interference fit.
Mechanical force will be required for larger
joints. Be ready in advance. Pipe pullers are
commercially available for this purpose.
Polyester pipe slings are very useful for
gripping a pipe, in order to apply a winch or
lever.
9. Hold the joint
Hold the joint against movement and
rejection of the spigot for a minimum of 30
seconds. Disturbing the joint during this
phase will seriously impair the strength of
the joint.
10. Wipe off excess solvent cement
For a neat professional joint wipe off excess
solvent cement , with a clean rag,
immediately from the outside of the joint.
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11. Do not disturb the joint
Once the joint is made, do not disturb it for five minutes or rough handle it for at least one
hour. Do not fill the pipe with water for at least one hour after making the last joint. Do
not pressurise the line until fully cured.
12. Cure the joint
The process of curing, is a function of temperature, humidity and time. Joints cure faster
when the humidity is low and the temperature is high. The higher the temperature, the
faster the joints will cure. As a guide, at a temperature of 16°C and above, 24 hours
should be allowed, at 0°C, 48 hours is necessary.
Joining HDPE Pipe
A pipeline is only as strong as its weakest connection. When it comes to joining HDPE pipe,
there are several common methods that are used, each with its advantages and
disadvantages. In this article, we’ll discuss four different methods: butt welding, electrofusion,
flanging and mechanical coupling
Butt Welding
Butt welding (or butt fusion) jointing is a thermo fusion process which involves the
simultaneous heating of the ends of two components which are to be joined until a melt state
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is attained on each contact surface, thereby producing a permanent, economical and flow-
efficient connection.
The two surfaces are then brought together under controlled pressure for a specific cooling
time and homogeneous fusion is formed upon cooling. The resultant joint is resistant to end
thrust and has comparable performance under pressure to the pipe.
This method of jointing requires an electrically heated plate to raise the temperature of the
pipe ends to the required fusion temperature and is used for PE63, PE80 and PE100 grades
of material for pipe of size 32mm and above of the same Standard Dimension Ratio (SDR).
When joining pipes using butt welding techniques.
Electrofusion
Another technique using heat fusion joining technology is electrofusion. Electrofusion welding
systems are considered the most highly developed cost-effective and safe method for joining
polyethylene pipes today.
This jointing process uses heat generated from electricity to melt both the pipe wall and the
pipe surface, creating a completely homogenous joint that is stronger than the pipe itself.
Thanks to its versatility, electro fusion can be used to weld together pipes or fittings from
different PE materials and different thicknesses as long as there is compatibility of melt flow
index and raw material density.
Another key advantage of electro fusion is that it is particularly suited to installations where
access is difficult, such as in trenches or around other pipes.
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A typical electro fusion weld is carried out by a trained welder and includes from operation
sheet:
Flanged Connections
Flanged joints are normally used to connect PE pressure pipelines to valves, pumping
stations and pipelines of other pipe materials. The joint must be able to transfer long-term
axial forces with maintained tightness, which requires use of suitable components and a
correct assembly.
The components in a flanged joint for HDPE pipes are:
Stub-ends or flanged adaptors
Back-up flanges
Gaskets (pressure and chemical appropriate)
Bolts
Washers
The general procedure for making flanged connections is:
1. Flanges and gasket should be centered, supporting one or both halves of the joint if
necessary
2. The end surfaces of the stub-ends must be close to each other before the bolts are tightened
to avoid elongation of the pipe during joint assembly.
3. Bolts are tightened crosswise in at least six stages, starting with finger tightening, and
consequently using a torque wrench
4. Additional tightening to the recommended torque should be carried out several hours later
and also on the next day
As a rule of thumb, the sealing pressure should be at least twice the maximum internal
pressure in the pipe.
Mechanical Compression Coupling
Compression couplings are another form of non-permanent jointing for HDPE pipes. As
indicated below, the general components of a compression fitting or coupling are a body, a
threaded compression nut, an elastomer seal ring or O-ring, a stiffener and a grip ring.
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Philmac Compression Fitting
Compression fittings are popular because they do not require soldering, so they are
comparatively quick and easy to use and require no special tools or skills to operate.
Because compression fittings are not permanent, they are especially useful in installations
that may require occasional disassembly or partial removal for maintenance.
The procedure for installing compression fittings is:
Cut the pipe at 90° to its axis
Inter over the pipe end in the following order: nut, clinch ring and O-ring on the mouth of the
pipe
Insert the pipe end and the O-ring onto the body of the joint, up to the insertion depth tab
Push the clinch ring into the body of the joint
Engage the nut and fully tighten
PE Pipe Joining Procedures
PE pipe or fittings are joined to each other by heat fusion or with mechanical fittings.
PE pipe may be joined to other pipe materials by means of compression fittings, flanges, or
other qualified types of manufactured transition fittings.
Thermal Heat Fusion Methods
There are three types of conventional heat fusion joints currently used in the industry;
1. Butt,
2. Saddle, and
3. Socket Fusion.
Additionally, electro-fusion (EF) joining is available with special EF couplings and saddle
fittings. The principle of heat fusion is to heat two surfaces to a designated temperature, then
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fuse them together by application of a sufficient force. This force causes the melted materials
to flow and mix, thereby resulting in fusion. When fused according to the pipe and/or fitting
manufacturers’ procedures, the joint area becomes as strong as, or stronger than, the pipe
itself in both tensile and pressure properties and properly fused joints are absolutely leak
proof. As soon as the joint cools to near ambient temperature, it is ready for handling.
Butt Fusion
The most widely used method for joining individual lengths of PE pipe and pipe to PE fittings
is by heat fusion of the pipe butt ends as illustrated in Figure 1. This technique produces a
permanent, economical and flow-effcient connection.
Figure 1 A Standard Butt Fusion Joint
The six steps involved in making a butt fused joint are:
1. Clean, clamp and align the pipe ends to be joined
2. Face the pipe ends to establish clean, parallel surfaces, perpendicular to the center line
3. Align the pipe ends
4. Melt the pipe interfaces
5. Join the two pipe ends together by applying the proper fusion force
6. Hold under pressure until the joint is cool
Saddle/Conventional Fusion
The conventional technique to join a saddle to the side of a pipe, illustrated in Figure 3,
consists of simultaneously heating both the external surface of the pipe and the matching
surface of the “saddle” type fitting with concave and convex shaped heating tools until both
surfaces reach proper fusion temperature. This may be accomplished by using a saddle
fusion machine that has been designed for this purpose
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Figure 3 Standard Saddle Fusion Joint
There are eight basic sequential steps that are normally used to create a saddle fusion joint:
1. Clean the pipe surface area where the saddle fitting is to be located
2. Install the appropriate size heater saddle adapters
3. Install the saddle fusion machine on the pipe
Prepare the surfaces of the pipe and fitting in accordance with the recommended procedures
5. Align the parts
6. Heat both the pipe and the saddle fitting
7. Press and hold the parts together
8. Cool the joint and remove the fusion machine
Socket Fusion
This technique consists of simultaneously heating both the external surface of the pipe end
and the internal surface of the socket fitting until the material reaches the recommended
fusion temperature, inspecting the melt pattern, inserting the pipe end into the socket, and
holding it in place until the joint cools. Figure 4 illustrates a typical socket fusion joint.
Mechanical equipment is available to hold both the pipe and the fitting and should be used
for sizes larger than 2”.
Figure 4 Standard Socket Fusion Joint
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Follow these general steps when performing socket fusion:
1. Thoroughly clean the end of the pipe and the matching inside surface of the fitting
2. Square and prepare the pipe end
3. Heat the parts
4. Join the parts
5. Allow to cool
Equipment Selection
Select the proper size tool faces and heat the tools to the fusion temperature recommended
for the material to be joined.
Square and Prepare Pipe
Cut the end of the pipe square. Chamfer the pipe end for sizes 1¼”-inch diameter and larger.
(Chamfering of smaller pipe sizes is acceptable and sometimes specified in the instructions.)
Remove scraps, burrs, shavings, oil, or dirt from the surfaces to be joined. Clamp the cold
ring on the pipe at the proper position, using the integral depth gauge pins or a separate
(thimble type) depth gauge. The cold ring will assist in re- rounding the pipe and provide a
stopping point for proper insertion of the pipe into the heating tool and coupling during the
fusion process.
Heating
Check the heater temperature. Periodically verify the proper surface temperature using a
pyrometer or other surface temperature measuring device. If temperature indicating markers
are used, do not use them on a surface that will come in contact with the pipe or fitting. Bring
the hot clean tool faces into contact with the outside
surface of the end of the pipe and with the inside surface of the socket fitting, in accordance
with pipe and fitting manufacturers’ instructions.
Joining
simultaneously remove the pipe and fitting from the tool using a quick “snap” action. Inspect
the melt pattern for uniformity and immediately insert the pipe squarely and fully into the
socket of the fitting until the fitting contacts the cold ring. Do not twist the pipe or fitting during
or after the insertion, as is the practice with some joining methods for other pipe materials.
Cooling
Hold or block the pipe in place so that the pipe cannot come out of the joint while the mating
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surfaces are cooling. These cooling times are listed in the pipe or fitting manufacturer’s
instructions.
Electrofusion (EF)
This technique of heat fusion joining is somewhat different from the conventional fusion
joining thus far described. The main difference between conventional heat fusion and electro
fusion is the method by which the heat is applied. In conventional heat fusion joining, a
heating tool is used to heat the pipe and fitting surfaces. The electro fusion joint is heated
internally, either by a conductor at the interface of the joint or, as in one design, by a
conductive polymer. Heat is created as an electric current is applied to the conductive
material in the fitting. Figure 5 illustrates a typical electro fusion joint. PE pipe to pipe
connections made using the electro fusion. Process requires the use of electro fusion
couplings.
General steps to be followed when performing electro fusion joining are:
1. Prepare the pipe (scrape, clean)
2. Mark the pipe
3. Align and restrain pipe and fitting per manufacturer’s recommendations
4. Apply the electric current
5. Cool and remove the clamps
6. Document the fusion process
1. Prepare the Pipe (Clean and Scrape)
Assure the pipe ends are cut square when joining using electro fusion couplings.
The fusion area must be clean from dirt or contaminants. This may require the use
of water or 90% isopropyl alcohol (NO ADDITIVES OR NOT DENATURED). Next, the pipe
surface in the fusion must be scraped, that is material must be removed to expose clean
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virgin material. This may be achieved by various special purpose tools available from the
fitting manufacturer.
2. Mark the Pipe
Mark the pipe for stab depth of couplings or the proper fusion location of saddles.
(Caution should be taken to assure that a non-petroleum marker is used.)
3. Align and Restrain Pipe or Fitting per the Manufacturer’s Recommendations
Align and restrain fitting to pipe per manufacturer’s recommendations. Place the pipe(s) and
fitting in the clamping fixture to prevent movement of the pipe(s) or fitting. Give special
attention to proper positioning of the fitting on the prepared pipe surfaces. Large pipe
diameters may need re-rounding prior to the electro fusion process.
4. Apply Electric Current
Connect the electro fusion control box to the fitting and to the power source (see Figure 6).
Apply electric current to the fitting as specified in the manufacturer’s instructions. Read the
barcode which is supplied with the electro fusion fitting. If the control does not do so
automatically, turn off the current when the proper time has elapsed to heat the joint properly.
5. Cool Joint and Remove Clamps
Allow the joint to cool for the recommended time. If using clamps, premature removal from
the clamps and any strain on a joint that has not fully cooled can be detrimental to joint
performance.
2. Mechanical Connections
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As in the heat fusion methods, many types of mechanical connection styles and methods are
available.
PE pipe, conduit and fittings are available in outside diameter controlled. Iron Pipe Sizes
(IPS), Ductile Iron Pipe Sizes (DIPS), Copper Tubing Sizes (CTS) and Metric Sizes. Before
selecting mechanical fittings, establish which of the available piping system sizes and types
are being installed to ensure proper fit and function.
Mechanical Compression Couplings for Small Diameter Pipes
This style of fatting comes in many forms and materials. The components, as depicted in
Figure 7, are generally a body; a threaded compression nut; an elastomer seal ring or O-ring;
a stiffener; and, with some, a grip ring. The seal and grip rings, when compressed, grip the
outside of the pipe, effecting a pressure-tight seal and, in most designs, providing pullout
resistance which exceeds the yield strength of the PE pipe. It is important that the inside of
the pipe wall be supported by the stiffener under the seal ring and under the gripping ring (if
incorporated in the design), to avoid deflection of the pipe.
Stab Type Mechanical Fittings
Here again many styles are available. The design concept, as illustrated in Figure 8, is
similar in most styles. Internally there are specially designed components including an
elastomer seal, such as an “O” ring, and a gripping device to effect pressure sealing and
pullout resistance capabilities. Self-contained stiffeners are included in this design. With this
style fitting the operator prepares the pipe ends,
Nut
Body Gasket
PE Pipe
Insert Stiffener Grip Ring Spring Washer
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marks the stab depth on the pipe, and “stabs” the pipe in to the depth prescribed for the
fitting being used.
Mechanical Bolt Type Couplings
There are many styles and varieties of “Bolt Type” couplings available to join PE to PE or
other types of pipe such as PVC, steel and cast iron in sizes from 1¼” IPS and larger.
Dismantling Joint
Dismantling joints simplify installations and replacement of flanged fittings in retroftting
applications. Dismantling Joints provide the solution for adding, repairing or replacing flanged
fittings within a flanged pipe system. In all applications, a restrained dismantling joint is
required unless otherwise specified.
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Mechanical Joint Saddle Fittings
Mechanical joint saddle fittings have at least one mechanical joint which may connect the
outlet to the service or branch pipe, or may connect the fitting base to the main, or both
connections may be mechanical joints. Mechanical joint saddle fittings are made from PE,
metals, and other materials.
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Self-Check -2
Written Test
Directions: Answer all the questions listed below. Use the Answer sheet provided in the
next page:
I.Choose the best answer for the following question (2pts each)
1. Which one of the following is not the part of pipe joining method?
A. Gasket (most common) B. Welded (typically steel)
C.Solvent Cement (PVC & ABS) D. Valve
2. ________ are normally used to connect PE pressure pipelines to valves, pumping stations
and pipelines of other pipe materials
A. Heat Fused (HDPE & PE)
B. Flanged (most common joint geometry)
C. Mechanical Couplings (CMP)
D. Brazed joint
3. Which type of welding systems is considered the most highly developed cost-effective and
safe method for joining polyethylene pipes today?
A. Electrofusion welding B. Soldered joint C. Grooved joint flanged joint
4. When pipes are joined with the help of molten filler material at above 840°C, it is called
________.
A. Brazed joint B. Compression joint C. Soldered joint D.Grooved joint
5. When pipes are joined by screwing in threads which are provided in the pipe, it is called
__________
A. Threaded joint
B. Flanged joint
C. Soldered joint
D. all
Note: Satisfactory rating - 10 points Unsatisfactory - below 10 points
You can ask you teacher for the copy of the correct answers.
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Answer Sheet
Name: _________________________ Date: _______________
Choose
1. ________
2. ________
3. _________
4. ___________
5. _____________
Score = ___________
Rating: ____________
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Information Sheet-3 Setting- out Configuration of pipes and fittings
3.1. Introduction to setting out of pipe line
Arrangement of equipment’s and piping is a primary activity of a piping engineering
department. Preliminary equipment layout is done before piping study. Final equipment
locations are decided based on all piping layout requirements are considered.
One of the critical parameters to set out the configurations of pipe is determining work
requirements from plan and specification. Work requirements are determined from plans and
specifications for example given the following drawing and specification work requirements
can be obtained as follows
Figure 3 simple water distribution system
Figure 3.1. water distribution pipe line configuration plan
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Figure 3.2. Fitting arrangement
Specification may be material or work specification
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3.2. Determine Work specification
Examples
1. Excavation depth for the service pipe should be 20cm depth
2. The width of excavation should be directed by the site engineer
3. Site clearing should include removing of tree
Material specification examples
1. For sealing purpose Teflon should be used
Having the drawing and specification work requirement should be determined. The following
list illustrate the work requirement
1. All the necessary materials, tools and equipment required for the work should be prepared
and provided on the site.
2. The service pipe have a length of 33m and a depth of 20cm excavation
3. Bedding materials are paced according to the site engineer recommendation
4. The position of the different types of fitting should be read from the fitting arrangement
5. A service pipe of 2”(15m) and 1”(17m) should be used e.tc.
Preparing Tube Joints
Apply compound to pipe threads only.
Screw the fitting clockwise by hand.
Tighten with a pipe wrench (wipe off excess compound).
Figure 3.3. Pipe configuration using fitting
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Preparing Joints for Copper Fittings
The various types of copper tubing fittings for soldered and flared joints are shown below.
Figure3.4. different types of copper fitting
Preparing Copper Tube Joints (Rigid)
Flux completely around the outside end of the tubing and the inside end of the fitting.
Place fitting on tubing. Use a quarter turn to spread the flux evenly.
Heat fitting with a torch until flux bubbles. Place solder on the connection until beads form
completely around the edge of the fitting.
Clean the joint with a wet cool rag.
Figure 3.5. copper pipe arrangement with fitting
Flared Joints
Place flange nut over the cut end of tubing with threads facing the cut end; then flare the
tubing at the cut end.
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Screw the flange nut on the fitting by hand.
Tighten the screw using two wrenches, one on the fitting and one on the flange nut.
Figure 3.6. flared joints
Preparing Copper Tube Fittings (Flexible)
Ensure tubing is cut square.
Slide compression nut and ring onto tubing. SLIDE fitting onto tubing.
Hold compression nut and ring against the fitting and turn the nut clockwise until it holds.
Tighten the compression joint with wrenches, using one wrench on the nut and one wrench
on the fitting.
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Figure 3.6. Flexible copper type of fitting
Attaching Fittings to Rigid Plastic Pipes to Form Solvent Welded Joints.
Swab the solvent weld cement around the outside of the pipe end.
Swab the solvent weld cement to inside of the fitting.
Push the fitting on the pipe using a quarter turn to spread the cement evenly.
Hold the fitting firmly on the pipe for about a minute.
Wipe excess cement from around fitting.
Attaching Fittings to Flexible Plastic Pipes to Form Clamped Joints.
Slide the metal clamp on the pipe.
Push the pipe on the fitting as far as it can go.
Move the clamps in place.
Tighten with a screwdriver
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Figure 3.7. flexible plastic pipes with clamped joints
Factors that affect the pipe-wall-thickness requirement, which include:
The maximum and working pressures.
Maximum and working temperatures
Chemical properties of the fluid.
The fluid velocity.
The pipe material and grade.
The safety factor or code design application
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Self-Check -2
Written Test
Directions: Answer all the questions listed below. Use the Answer sheet provided in the next
page:
I. Choose the best answer for the following question (2pts each)
1. Which one of the following is primary activity of a piping engineering?
A. Arrangement of equipment and piping
B. Preliminary equipment layout is done before piping study.
C. Equipment locations are decided based on all piping layout requirements are considered.
D. All
2. factors that affect the pipe-wall-thickness requirement includes the following except:
A.The maximum and working pressures
B.Maximum and working temperatures.
C.Chemical properties of the fluid and the fluid velocity.
D.The pipe material, grade and the safety factor or code design application
All f. none.
II.Matching column A(fitting name ) with column B (fitting symbol for each number
A( fitting type for each number) B (pipe fitting configuration)
1. GS nipple
2. Gate valve
3. union
4. GI Tee
5. Reducer
6. Coupling
Note: Satisfactory rating – 5and above points Unsatisfactory - below 5 points
You can ask you teacher for the copy of the correct answers.
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Answer Sheet
Name: _________________________ Date: _______________
Choose
1. ____
2. ______
3.
Matching
1. _________
2. ___________
3. ____________
4. _____________
5. ____________
6. _____________
Score = ___________
Rating: ____________
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Information Sheet-4 Recognizing Joining faults or malfunctions
5.1. Introduction to pipe joint faults
Failure at these joints led to complete separation of pipe segment one to segments. The
primary objectives of this pipeline experiment were to identify failure. The most common
faults
Dripping faucets.
Miss alignment of pipe
In appropriate material use
High water pressure
Slow draining sink.
Clogged bath or shower drain.
Clogged toilet.
Running toilet.
Faulty water heater.
Low water pressure.
Jammed garbage disposal.
Figure 4.1 examples of pipe leak
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Self-Check -4
Written Test
Directions: Answer all the questions listed below. Use the Answer sheet provided in the
next page:
I. Choose the best answer for the following question (5pts each)
1. Which one of the following is not the cause of pipi joining faults?
A. Miss alignment of pipe joint
B. In appropriate operation of pipe
installation
C. In appropriate material use
D. High pressure of water
E. All
Answer Sheet Score = ___________
Rating: ____________
Note: Satisfactory rating – 2.5.and above points Unsatisfactory - below 2.5. points
You can ask you teacher for the copy of the correct answers.
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Name: _________________________ Date: _______________
Choose
1. ____
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Information Sheet-5 Selecting place, bedding and backfill material
5.1. Introduction Trenching, installation, bedding and backfilling
To provide stability and protection for the pipe and increases the bearing capacity for
external loads. The type of material used depends on the pipe characteristics and soil
conditions.
Fine material should always be used for the initial backfill; excavated sub-soil may also be
suitable. Stones, rocks and any sharp materials are not allowed close to the pipe.
The soil is normally placed in the trench in layers of 15-20 cm, and each layer is well
compacted by machines that do not damage the pipe.
The pipe can also be partly surrounded by the initial backfill but this reduces its supporting
strength to a large extent.
Top backfill in urban areas usually has to follow specifications required by road authorities, in
open areas it is more related to aesthetics
A specified grade and alignment for a trench is generally determined by the project engineer.
The drawings and bid documents will specify the correct line and grade to be established by
the trenching operation.
Width of trench
The width of the top of the trench will be determined by local conditions.
Trench widths should be kept as close to the minimum as possible.
As a norm, a trench width should be kept to 300mm wider than the diameter of the pipe to
allow space around the pipe for jointing and initial compaction.
Depth
Common practice stipulates a minimum cover of 900mm above the crown of the pipe, which
is determined by the following factors:
Loads imposed on the pipe by mass of backfill material
Degree of compaction of backfill
Expected traffic loads
Possibility of future excavations in the vicinity of the pipeline
The actual trench depth allows for the specified minimum cover, the pipe diameter and the
specified minimum bedding depth (100mm)
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Bedding
The bed of the trench must be inspected and cleared of any hard or sharp projections which
may cause damage to the pipe. The bedding should be carefully and uniformly compacted
and leveled with suitable material. Granular materials are preferred as they contain little or no
fines and require minimal compaction.
The majority of particles in the bedding material should be no more than 20mm; however, it
is permissible for a small percentage of particles to exceed this amount up to 40mm.
Laying of Pipe
To prevent damage, proper implements, tools and equipment should be used for placement
of the pipe in the trench.
Under no circumstances should the pipe or accessories be dropped into the trench.
All foreign matter or dirt should be removed from the pipe interior.
Pipe joints should be assembled with care.
When pipe laying is not in progress, open ends of the installed pipe should be closed to
prevent entrance of trench water, dirt and foreign matter into the line.
Haunting
launching the material placed to the sides of the pipe from the bedding to about the spring
line (center line), is intended to help the pipe support the vertical loads. It is frequently a
material with sizes not over 1-1/2" (38mm).
Initial Backfill
The material placed over the pipe itself to a height of 6 to 12" (150mm - 300mm) above the
top of the pipe is the initial backfill. The maximum size of stone in the initial backfill, where
not specified, should be 1-1/2" (38mm). Where it is not otherwise specified the initial backfill
may consist of the native material in the trench provided it is free from large stones, not
frozen, and free of debris or other organic materials. The purpose of the initial backfill is to
protect the pipe from the final backfill.
Final Backfill
The material placed over the initial backfill to the top of the trench is the final backfill. If not
otherwise specified the final backfill material may contain boulders up to 4" (100mm) in
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diameter and may consist of native material. final backfill should contain no large stones or
large rocks, frozen material or debris.
Backfilling Material
The same material used for the bedding should form the side filling and initial backfilling
(overlay) and should be compacted to 300mm above the crown of the pipe. For the rest of
the backfilling, excavated material from the site can be used, unless otherwise specified by
the engineer
Backfill Considerations
Backfill should be clean
free of roots, limbs, and debris
Backfill trenches as soon as possible
Leave internal bracing in pipe until backfill is
complete
Ensure specified degree of compaction is
achieved throughout backfill, or ensure that
backfill is mounded if no compaction required
Kicker berms to deflect runoff from
following trench
Compacting the Backfill
Compact the haunching, initial backfill and final backfill in accordance with the job drawings.
Figure 5. Typical bedding detail
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Figure 5.1. Back filling and compaction
Figure 5.2. Back filling with shoring support
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Self-Check -5
Written Test
Directions: Answer all the questions listed below. Use the Answer sheet provided in the
next page:
I. Choose the best answer for the following question (5pts each)
1. Which one of the following is the purpose of pipe laying?
A. To prevent damage, proper implements, tools and equipment
B. Under no circumstances should the pipe or accessories be dropped into the trench.
C. All foreign matter or dirt should be removed from the pipe interior.
D. Pipe joints should be assembled with care. E. all F. None
2. Depth of a back fill determined by the following factor except
A. Loads imposed on the pipe by mass of backfill material
B. Degree of compaction of backfill
C. Expected traffic loads
D. Possibility of future excavations in the vicinity of the pipeline
E. All f. none
3. Which one of the following statements are true width of trench
A. The width of the top of the trench will be determined by local conditions.
B. Trench widths should be kept as close to the minimum as possible.
C. a trench width should be kept to 300mm wider than the diameter of the pipe to allow
space
D. All F. none
4. _________used to provide stability and protection for the pipe and increases the bearing
capacity for external loads
A. Trench excavation
B. Back filling and compaction
C. Over load
D. Removal of soil
Note: Satisfactory rating – 5 and above points Unsatisfactory - below 5 points
You can ask you teacher for the copy of the correct answers.
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Answer Sheet
Name: _________________________ Date: _______________
Choose
1. _________
2. __________
3. __________
4. _____________
5. _______________
Score = ___________
Rating: ____________
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Operation Sheet 1 Perform Pipe cutting procedure
Activity1. Pipe cutting procedure by hacksaw
1. Select the appropriate PPE, tools and equipment
2. Adjusting the equipment
3. Before you start sawing, make sure you have measured and marked the correct length.
4. Clamp the pipe as short as possible to prevent rotating during cutting and to prevent
unnecessary vibration
5. Use the edge of a file to make a notch at the marked position. This notch will make it easy to
start with sawing.
6. Saw with steady, even strokes, keeping the blade upright and square in the cut. Use the full
length of the blade.
7. Before finishing the cutting operation, the pipe must be supported with one hand. This will
prevent the fall of the cut pipe and prevent the blade of the hacksaw being damaged.
Activity2. Pipe cutting procedure Cutter
1. Select the appropriate PPE
2. Select the appropriate tools and equipment
3. Prepare the working area
4. Adjusting the equipment
5. Measured the correct length
6. Clamp the pipe
7. Mark the cutting position
8. After mounting the pipe cutter to the pipe, tighten the feeding screw so that the cutting wheel
is touching the pipe.
9. Rotate the pipe cutter around the pipe.
10. After the first or second turn, check that the cutting wheel is hitting exactly the scribed line.
11. Keep rotating and every two or three turn’s use the feeding screw to put some more pressure
on the cutting wheel.
12. Before the cut is completed support the pipe with your left hand so that it does not fall. Since
cutting the pipe in this manner leaves a large ridge on the inside of the pipe, which would
obstruct the flow, the pipe must be de−burred or reamed with a file or a pipe reamer.
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13. Filing and De−burring the Pipe After cutting the pipe check the squareness of the pipe end. If
it is necessary file it to the right angle
Operation Sheet 2 Performing Pipe threading
Activity1.pipe threading procedure
1. Select the appropriate PPE
2. Select the appropriate tools and equipment
3. Prepare the working area
4. Adjusting the equipment
5. Measured the correct length
6. Clamp the pipe
7. Select the correct die head
8. Put the die head in the ratchet socked using the knob to open and close the socket
9. Check the correct position of die head
10. Fix the pipe in a suitable vice (pipe extension within 150 mm to 250 mm)
11. Apply a cutting lubricant to the part, which is to be threaded. During threading apply from
time to time some new lubricant. Catch the dropping down lubricant and the chips in a box.
Otherwise it will contaminate the floor and make it slippery
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12. Bring the die−stock to the pipe and apply a little pressure to the stock. Keep the handle at
right angles to the pipe axis. Rotate the handle clockwise with slight pressure towards the
pipe, at right angles to the pipe axis. 25
13. When the dies "bite" into the pipe, stop pushing and simply continue the rotation, by moving
the handle up and down
14. If the die sticks there are probably some metal chips in the way. To break the metal chips,
reverse the knob and move the die anti−clockwise for half a round. Then proceed with
cutting.
15. After cutting the full length of thread reverse the knob and move the die anti−clockwise until
you can take it off.
16. Finally, clean off the threads with a wire brush and some cleaning rag.
17. Test the thread with a fitting (elbow or tee). If it is to tight, adjust the dies again and repeat
the threading operation.
18. Finally clean the stock and die and store them properly.
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Operation Sheet 3 Performing Pipe assembling
Pipe assembling procedure
1) Select the appropriate PPE and tools and equipment
2) Prepare the working area
3) Adjusting the equipment
4) Clamp the pipe
5) Fix the pipe in an applicable pipe vice
6) If necessary clean the pipe with a steel brush or a cleaning rag
7) Make sure that the pipe is also clean inside. Remove any burr and other materials
8) To make a sound screw joint, threads must engage freely and it should be possible to turn
the fitting for the first few turns by hand without any difficulty
9) Wrap "Teflon" tape round the male thread in the same direction as the male thread. Do not
apply sealing compound. Screw the pipe fitting onto the end of the galvanized pipe by hand
as far as it will go
10) Now use a pipe wrench. Adjust the wrench to the right size while using the adjustment wheel.
11) Continue the screwing process, using gradual, even increase in force to tighten the threads
together. Do not over−tighten the fitting. This can cause a pipe fitting to split.
12) If you assemble two pipe joints (a fitting in between) then use two pipe wrenches.
13) To assemble pipes with a diameter bigger than 2", the use of a chain wrench is sometimes
recommended. But do not use it for diameters below 2". Otherwise the pipe might be
flattened or damaged.
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Union: When the threaded ends of two pipes meet, the best way to assemble them, or
connect them, is to use a union. This makes it easy to take the pipe system apart for repairs.
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Actually there are two different types of unions available:
One with a ground joint, which does not acquire a sealing to make the connection watertight.
One, which requires a soft rubber, leather or "Teflon" washer to make the connection
watertight.
Note: A little grease on the union joint ensures easy disconnection. Use two pipe wrenches
to assemble or tighten the union. Hold one side of the union in one pipe wrench and the ring
of the union in the other. Turn the two pipe wrenches gently in opposite directions until it is
tightening
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Operation Sheet 4 Performing Pipe joining by welding
Steps for pipe welded joint a
Activity 1. Pre-welding procedure
1. Create an environment conducive to repeatability and reproducibility, thus a clean tidy and
stable environment at the point of fusion
2. Ensure the use of clean and appropriate equipment
3. Only use trained personnel
4. Draw up preliminary welding procedures
5. Weld according to preliminary welding procedures
6. Perform a visual inspection on the welded section
7. Perform mechanical tests on welded sections
8. Make process changes until all aspects achieve a pass status
9. Continue with the welding processes and make sure to record all important parameters
10. Make use of check sheets to ensure accurate tracking of all important steps and parameters
Activity 2. Welding procedure
1. Place the pipes in clamps with ends against the trimming tool and pipe markings aligned
2. Align and level components using support rollers
3. Tighten the pipe clamps to grip and re-round the pipes
4. Use the trimming tool to ensure continuous shavings are cut from each surface
5. Check that there is no visible gap between the trimmed faces
6. Place the heater plate in the machine and close the clamps so that the surfaces to be joined
are touching the plate
7. Using the hydraulic system, apply the pressure previously determined
8. Maintain the applied pressure until the pipe begins to melt and uniform bead of 2-3mm is
formed on each end
9. Check that the pipe does no slip in the clamps. The pipe ends must maintain contact with the
heater plates
10. Once the heat soak time is completed, remove the heater plate, ensuring that the plate does
not touch the melted surfaces
11. Immediately close the clamps and bring the melted surfaces together at the previously
determined pressure
12. Hold under pressure for the appropriate cooling time
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Where possible, choose a site that is ventilated, under shade and away from wind
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Do not disturb for at least 5 minutes (not illustrated).
Do not apply pressure for at least 24 hours.
Lubricant
A lubricant will considerably reduce the effort required to make a joint AND will minimise the
possibility of dislodging the rubber ring. The lubricant used should be water soluble, non-toxic
and preferably of a gel consistency. The following alternative lubricants should NOT be used:
Oil, grease, diesel, dishwashing liquid, etc.
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Activity 3. Joining PPR Pipe
PPR (polypropylene random copolymer) is the standard pipe material in many other parts of
the world. Instead of PVC cement, PPR joints are heated by a special fusion tool and
essentially melted together into a single piece. When created properly using the right
equipment, a PPR joint will never leak.
2.1.1.2. Heating the Fusion Tool and Preparing the Pipe
2. Place the right-sized sockets onto the fusion tool. Most PPR fusion tools come with
pairs of male and female sockets of various sizes, which correspond to common PPR pipe
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diameters. So, if you’re using PPR pipe that's 50 millimetres (2.0 in) in diameter, choose the
socket pair marked for 50 mm
3. Plug in the fusion tool to begin heating the sockets. Most fusion tools will plug into a
standard 110v outlet. The tool will either start heating immediately, or you may have to turn
on a power switch. Models vary, but it will likely take several minutes for the tool to heat the
sockets to the necessary temperature.
Be very careful around a hot fusion tool, and make sure everyone in the area knows it’s on
and hot. The sockets reach temperatures of over 250 °C (482 °F) and can cause severe
burns.
4. Trim your pipe to length with a smooth, clean cut. While the fusion tool heats, mark
and cut your pipe to the desired length. Many fusion tool sets come with a trigger- or pincer-
style pipe cutter. When used according to the directions, these will create smooth, even cuts
in PPR that are ideal for fusion welding.
PPR pipe can also be cut with a variety of hand or power saws, or wheel-style pipe cutters.
However, make sure the cuts are as smooth and even as possible, and clear away any burrs
with fine-grit sandpaper.
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5. Clean the PPR pieces with a cloth and the recommended cleaner. Your fusion tool kit
will likely recommend, and may even come with, a specific cleaner to use with PPR pipe.
Use this cleaner as directed on the outside of the pipe and the inside of the fitting to be
joined. Let the pieces dry for a few moments.
If you don’t know what type of cleaner to use, contact the manufacturer of your fusion tool.
6. Mark the welding depth on the joining end of the pipe. Your fusion tool set will likely
come with a template for marking the proper welding depths onto various diameters of PPR
pipe. Use a pencil to make the corresponding mark on the pipe.
Alternatively, you can stick a tape measure into the pipe fitting you’re using (e.g., an 90-
degree elbow fitting) until it hits the small ridge inside the fitting. Subtract 1 millimeter
(0.039 in) from this depth measurement and mark it as the welding depth on your pipe.
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7. Confirm that the fusion tool is fully heated. Many fusion tools have a display that tells
you when the tool is heated and ready to go. The target temperature is typically 260 °C
(500 °F)
If your fusion tool doesn’t have a temperature display, you can use a probe-style or infrared
thermometer to read the temperature on the sockets.
You can also buy temperature indicating sticks (e.g., Tempilstik) at welding supply stores.
Choose sticks that will melt at 260 °C (500 °F) and touch one to each socket
8. Heating the Pipe and Fitting on the Fusion Tool
9. Protect your skin from the very hot fusion tool. Before you start softening PPR pipe on
the fusion tool, put on heat-resistant work gloves and long sleeves. Also tie back any loose
hair and remove any dangling jewelry.
Temperatures of over 80 °C (176 °F) can cause severe skin burns in less than a second, and
the fusion tool heats up to 260 °C (500 °F)
10. Press the PPR pieces straight into/onto their respective sockets. If you have a table-
mounted fusion tool, hold the pipe in one hand and the fitting in the other so you can insert
them simultaneously. If you have a handheld fusion tool, insert one piece then the other in
rapid succession. Hold and insert the pieces straight in line with the sockets, not at an angle.
Push the pipe into the female socket until you reach the depth marking you put on it.
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Push the fitting onto the male socket until it touches the ridge or line marked on the socket
11. Start the heating timer, if your model has one. Many fusion tools have built-in timers
that will signal when your chosen diameter of PPR is ready to remove from the sockets.
Refer to your owner’s manual for instructions on how to activate the timer.
For some models, you might punch in the correct pipe diameter first, then the timer will
activate automatically when you place the PPR pieces on the sockets.
If your model doesn’t have a built-in timer, refer to the heating directions in the manual and
use a watch or clock to time the heating process.
Heating times can vary, with larger diameter pipes often taking a bit longer than smaller
ones.
12. Pull the PPR pieces straight off/out of the sockets. Just like when you put them in
place on the sockets, don’t remove the pipe or fitting at an angle. Otherwise, you’ll deform
the softened, nearly gooey PPR.
Pull the pieces off as soon as the alarm sounds or they’ve reached their heating time.
Otherwise, the ends will deform and melt.
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13. Fusing the Pipe and Fitting into One Piece
14. Push the pipe and fitting straight together immediately. As soon as you remove them
from the fusion tool, insert the pipe straight into the fitting until it reaches the depth line
marked on it. Don’t insert the pipe at an angle, and don’t twist either piece — just push the
pipe straight in.
Don’t wait more than 3-4 seconds before joining the pieces together.
People often twist PVC pipe pieces a bit when joining them in order to spread around the
cement, but resist this urge with PPR. You risk deforming the pipes and/or ruining the fusion
process.
15. Hold the fused pipe pieces in place for 30 seconds. PPR pipe heats very quickly and
cools very quickly. Within 30 seconds, the pieces will have cooled enough to have fused into
one piece of PPR pipe. You can then put the fused pipe down and move on to your next
task.
If you were to cut through the joint once the fused pipe completely cools, you wouldn’t be
able to tell where one piece ended and the other began. They have melted and reformed into
a single piece of PPR pipe.
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16. Put the pipe into service after it cools completely. Once the fused PPR pipe cools to
room temperature again, it is ready to withstand its rated water pressure. Once your
plumbing system is fully installed, you can turn on the water and check for leaks — but there
won’t be any.
PPR pipe should cool completely within 10-15 minutes at most
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Name: _____________________________ Date: ________________
Time started: ________________________ Time finished: ________________
Instructions: Given necessary templates, tools and materials you are required to perform the
following tasks within --- hour.
Task1. Perform pipe cutting by hand and hacksaw
Task2. Perform pipe threading
Task 3. Perform pipe assembling
Task 4. Perform pipe welding by pre-welding and welding PPR
LAP Test Practical Demonstration
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Instruction Sheet Learning Guide #- 29
This learning guide is developed to provide you the necessary information regarding the
following content coverage and topics –
Clearing of potential pollutants Service pipes and fittings)
Flushing service pipe work before final commissioning.
Plugging pipe openings during work breaks.
This guide will also assist you to attain the learning outcome stated in the cover page.
Specifically, upon completion of this Learning Guide, you will be able to
Store service pipes and fittings clear of potential pollutants or damaging substances and
remove debris or filling from pipes before installation.
Flush service pipe work before final commissioning.
Plug pipe openings during work breaks
Learning instruction
1. Read the specific objectives of this Learning Guide.
2. Follow the instructions described below 3 to 6.
3. Read the information written in the information “Sheet, Sheet 2, and sheet 3 and from
page(173,176 and 179) respectively and Accomplish the “Self-check 1,Self-check 2, and
self-check 3, in page -176,178 and 182 )respectively.
4. If you earned a satisfactory evaluation proceed to “Operation Sheet 1” and operation sheet 2
in page 183
5. Then accomplish LAP Tests,”1,2, in page 184 (if you are ready). Request your teacher to
evaluate your performance and outputs. ensure you have a formative assessment and get a
satisfactory result;
6. Then proceed to the next LG
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Information Sheet-1 Clearing of potential pollutants Service pipes and
fittings)
1.1. Introduction to water quality through pipe
The physical parameters (e.g. pipe age, material, diameter), operational parameters (e.g.
intermittency of supply, number of breaks and bursts, leakage in the system) and
environmental parameters (e.g. workmanship, bedding conditions, traffic) help to determine
the vulnerability of pipes to contaminant intrusion.
Hazards, hazardous events and risks are magnified in informal settlements compared with
adjoining urban areas. Population densities are much higher, sanitation is typically poorer,
with very limited sewerage systems, non-revenue water rates are high, and most residents
receive water from water kiosks and standpipes. Management of water systems in informal
settlements is often poor. Hence, the likelihood of hazardous events occurring is much
greater.
Some of the higher risks include:
poor sanitation due to:
open defecation and “flying toilets”
overflowing sewers, pit latrines, bio-toilets and
storm drains
open drainage and
poor solid waste management;
Inadequate supply due to
high leakage rates
illegal water closures by competing gangs
operating kiosks and
high cost of laying pipes
lack of storages
poor reporting and communication of leaks and
other failures
limited access, restricting maintenance and
repairs
limited governance, planning and operation
low ownership
poor pipe materials
illegal connections
inadequate protection of standpipes;
poor hygiene
of services, leading to theft of pipes and fittings
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pollution as the introduction by man, directly or indirectly, of substances or energy into the
marine environment (including estuaries) resulting in such deleterious effects as harm to
living resources, hazards to human health, hindrance to marine activities including fishing,
impairment of quality for use of sea water and reduction of amenities.
Contamination on the other hand is the presence of elevated concentrations of substances
in the environment above the natural background level for the area and for the organism.
Contamination of water by physical and bacteriological agents, be it drinking water, ice water
or harbor water, may be evaluated by laboratory tests. Test results are usually expressed in
parts per million (milligrams per liter or simply ppm) or parts per billion (micrograms per liter
or ppb) for physical parameters; and bacterial counts per 100 milliliters for organisms. For
both types of contaminant, maximum levels are usually stipulated and these levels may differ
from country to country.
The major contaminants of concern, in service pipe supplies are:
Suspended solids;
Biodegradable organics (proteins,
carbohydrates and fats);
Pathogens;
Nutrients (Nitrogen, phosphorus and carbon);
Priority pollutants (highly toxic chemicals);
Refractory organics (pesticides, phenols,
surfactants);
Heavy metals;
Dissolved inorganics (nuisance chemical
Pipeline cleaning methods vary from pipeline to pipeline and depend on many factors such
as pipe product, service, diameter and length. These methods are basically divided into three
categories such as
mechanical,
hydraulic and
Chemical cleaning.
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Control of water quality is required right from the source to consumer points, and
deterioration of water quality can be avoided in both water transmission and water
distribution systems. Useful information that can be collected includes the following:
Information about pipe material, size and year of installation;
pipe breakage history and leakage data;
operational parameters, such as intermittency of supply, metering data and non-revenue
water;
environmental parameters, such as workmanship, bedding conditions and traffic;
customer complaints regarding pipe breaks, supply of poorquality water and contamination;
information on water quality – at source, after treatment and at consumer locations – and
water age;
type of supply, per capita supply, extent of metering and extent of non-revenue water;
map showing open drainage and sewer networks;
information about sewerage and drainage systems;
solid waste dumping points;
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Self-Check -1
Written Test
Directions: choose the best answer all the questions listed below. Use the Answer sheet
provided in the next page
I.choose the best answer for the following question (3pts each)
1. one of the following is not Pipeline cleaning methods
a. mechanical,
b. hydraulic and
c. Chemical cleaning.
d. all
2. major contaminants of concern, in service pipe supplies are the following except
a. Suspended solids and Biodegradable organics (proteins, carbohydrates and fats)
b. Pathogens and Nutrients (Nitrogen, phosphorus and carbon); and Priority pollutants (highly toxic
chemicals) and
c. Refractory organics (pesticides, phenols, surfactants) and Heavy metals and Dissolved inorganics
(nuisance chemicals
d. All e. none
3. poor sanitation occurs through the pipe line due to the following
a. open defecation and “flying toilets”
b. overflowing sewers, pit latrines, bio-toilets and
storm drains
c. open drainage and
d. poor solid waste management;
4. Inadequate supply of water occurs through the pipe line due to the following factor except
A. high leakage rates
B. illegal water closures by competing gangs operating kiosks and high cost of laying pipes
C. lack of storages
D. All f. none
Note: Satisfactory rating – 6 and above points Unsatisfactory - below 6points
You can ask you teacher for the copy of the correct answers.
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Answer Sheet
Name: _________________________ Date: _______________
1. __________
2. __________
3. ___________
4. ___________
Score = ___________
Rating: ____________
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Information Sheet-2 Flushing service pipe work before final commissioning
2.1. Introduction to flushing service pipe
Foreign material left in the pipeline during installation often results in valve seat leakage
during pressure tests. Every effort should be made to keep lines clean during installation.
Thorough flushing is recommended prior to pressure testing. A pipe flush effectively removes
organic interference from the piping system.
Flushing the method for removing solids which are not cemented to the inside surface of
pipes is to flush with water at high velocity. Furthermore, whenever mains are opened for
repair, they should also be flushed and disinfected.
Flushing should be accomplished by partially opening and closing valves several times under
expected line pressure with adequate flow velocities to flush foreign material out of the
valves.
Flushing pipes as a preventative measure requires good planning. The following factors are
to be taken into consideration:
selection of the optimal pipe route,
the location of valves that are operated in order to isolate the flushed route from the rest of
the system,
total length of section that is flushed in one run,
choice of hydrants (number and location) that will have to be opened in order to generate the
necessary velocity,
Proper sequence of routes to be flushed.
Flushing is the simplest method of cleaning but with some disadvantages:
Large amounts of water used (particularly in large diameters)
It is less effective in low pressure areas
It may disturb flow patterns upstream of the cleaned section
In areas with active corrosion, it offers only a temporary improvement
The efficiency of flushing can be increased by injection of compressed air into
A continuous but smaller flow of water. Pushed by the air, the water will form into
Discrete slugs forced along the pipe at high velocities. The length that can be effectively
Cleaned by air scouring depends on:
available static pressure (higher pressure - longer length)
pipe friction (higher friction - shorter length)
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compressor size (larger compressor - longer length)
pipe gradient (longer lengths when cleaning uphill
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Self-Check -2
Written Test
Directions: choose the best answer all the questions listed below. Use the Answer sheet
provided in the next page
I. choose the best answer for the following question (3pts each)
1. _______ is the method for removing solids which are not cemented to the inside surface
of pipes is to flush with water at high velocity
A. Flushing B. Laying C. bending D. all
2. Which one of following Factors to be consider when planning good Flushing pipes
preventative measure
A. selection of the optimal pipe route,
B. the location of valves that are operated in order to isolate the flushed route from the rest of
the system,
C. total length of section that is flushed in one run,
D. Proper sequence of routes to be flushed.
E. All f. none
3. From the following which one is the disadvantages of Flushing
A. Large amounts of water used (particularly in large diameters)
B. It is less effective in high pressure areas
C. It may disturb flow patterns upstream of the cleaned section
D. In areas with active corrosion, it offers only a temporary improvement
4. The efficiency of flushing can be increased by injection of compressed air into a
continuous length that can be effectively cleaned by air scouring depends on the following
except
A. available static pressure (higher pressure - longer length)
B. pipe friction (higher friction - shorter length)
C. compressor size (larger compressor - longer length)
D. pipe gradient (longer lengths when cleaning uphill) E. all f. none
Note: Satisfactory rating – 6and above points Unsatisfactory - below 6points
You can ask you teacher for the copy of the correct answers.
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Answer Sheet
Name: _________________________ Date: _______________
1. _________
2. _________
3. _________
4. __________
Score = ___________
Rating: ____________
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Information Sheet-3 Plugging pipe openings during work breaks
3.1. Introduction to plugging for pipe opening
During work breaks to protect the service installation from unwanted material entry plugging
the pip is important. So do not forget to plug or sea. During the pipe is under in the working
condition there are different Common causes of failure.
Corrosion If valves are not operated or lubricated for a long time, they may become
inoperable due to corrosion. If the corrosion damage is not extensive, the valve may be
made operable again by pouring kerosene or dilute lubricating oil down the valve key to
lubricate the joint between the stem and packing. However, if the valve is still inoperable after
this procedure, it should be replaced.
Closing the Valve too tightly Closing the valve too tightly may damage the valve washer, the
valve seat, or the threads of the valve stem, causing the water to leak. To solve this problem,
it is suggested to put markers showing the direction of opening and closing and to close the
valve just tight enough to stop the flow of water.
Worn-out washer or loose packing Worn-out washers or loose packing should be replaced to
prevent the loss of water.
Cavitation results when a valve is left partially closed or open for a long period. Leaving a
valve partially closed or open will cause a partial vacuum or void in the downstream side that
may eventually be filled with low-pressure vapors from water. When these vapor pockets
collapse, a mechanical shock (cavitation’s) is created, this may produce cavities. After some
time, the valve will be destroyed and even the pipelines may be affected. cavitation’s can be
avoided by keeping the valves fully closed or fully opened at all times.
Water hammer is caused by sudden closing of valves. When the flow of water is suddenly
stopped, enormous pressure is created which may damage the pipe or valves. This problem
can be prevented by closing the valve slowly.
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Self-Check -3 Written Test
Directions: choose the best answer all the questions listed below. Use the Answer sheet
provided in the next page
I. choose the best answer for the following question (3pts each)
1. when there breaks pipe during the working condition what is there medial measure to
minimalizes loss of water and contamination of pipe
A. plugging the pipe
B. opening the pipe
C. increase flow rat
D. all
2. _________is caused by sudden closing of valves. When the flow of water is suddenly
stopped, enormous pressure is created which may damage the pipe or valves.
A. Water hammer
B. Flow velocity
C. Volume of water
D. All
3. Which one of the following is the Primary cause of pipe break?
a. Corrosion
b. Cavitation
c. Water hammer
d. All
Note: Satisfactory rating – 4.5. and above points Unsatisfactory - below 4.5. points
You can ask you teacher for the copy of the correct answers.
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Answer Sheet
Name: _________________________ Date: _______________
1. _________
2. _________
3. ___________
Score = ___________
Rating: ____________
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Operation Sheet 1 Performing for service pipe flushing
Service pipe flushing procedure
1. Isolate the water mains to be cleaned by closing the appropriate control valves
2. Empty the water mains by opening the blow-off valve or other temporary outlet at the lower
end of the pipeline
3. In some cases, to expedite the emptying of water mains without pumping, compressed air
may be introduced at the highest point of the isolated system,
4. Inject water at high-induced velocity until the objectionable materials are expelled,
5. Open all terminal fittings to produce as high a flow of water as possible.
6. Allow water to run until visually clear.
7. Continue to allow water to run for a further two minutes.
8. Confirm that the water is visually clear by filling an appropriate clean container such as clear
plastic bottle or washbasin with at least one liter of water.
9. If the water appears cloudy, discolored or contains any debris then repeat the flushing
process.
10. If after repeated flushing the water is not visually clear then contact your local Water Supplies
11. Put pipelines back to operation
12. As needed, disinfect the pipelines. After disinfection, flush the pipeline with clean water until
the chlorine-odor is hardly detectable
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Operation Sheet 2 Cleaning service pipe by disinfection
Disinfection procedures for series pipe of cleaning.
1. The pipe is flushed with water to carry away any contaminants.
2. The pipe is filled with water and dosed with about 50 ppm of chlorine.
3. The chlorinated water is allowed to sit in the pipe for a day to allow sufficient contact time to
disinfect the pipe surface and oxidize and contaminants.
4. After 24 hours, there should be at least 5 ppm chlorine residual remaining in the water,
indicating that the chlorine demand has been met.
5. At this point, the line is flushed again to remove all of the chlorine.
6. The pipe is refilled with water and the water is tested for coliform to ensure that the main is
properly disinfected.
7. Based on a clear coliform reading, the pipe may be placed in operation.
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Name: _____________________________ Date: ________________
Time started: ________________________ Time finished: ________________
Instructions: Given necessary templates, tools and materials you are required to perform
the following tasks within 8 hours.
Task 1. Perform for service pipe flushing
Task 2. Clean service pipe by disinfection method
LAP Test Practical Demonstration
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Instruction Sheet Learning Guide #- 30
This learning guide is developed to provide you the necessary information regarding the
following content coverage and topics –
Determining locations of leaks and isolate and dewater.
Identifying and applying electrical safety procedures.
Identifying and applying appropriate repair techniques to maintain integrity of service
This guide will also assist you to attain the learning outcome stated in the cover page.
Specifically, upon completion of this Learning Guide, you will be able to –
Determine locations of leaks and isolate and dewater.
Identify and apply electrical safety procedures.
Identify and apply appropriate repair techniques to maintain integrity of service.
Learning Instructions:
1. Read the specific objectives of this Learning Guide.
2. Follow the instructions described below 3 to 6.
3. Read the information written in the information “Sheet 1, Sheet 2 and sheet 3,” from page
(188,195and 197) respectively and accomplish the “Self-check 1. Self-check 2 and self-
check 3,” in page 194,196 and 199) respectively.
4. If you earned a satisfactory evaluation proceed to “Operation Sheet 1 and” in page 200.
5. Then accomplish LAP Tests,”1,2, in page 203 (if you are ready). Request your teacher to
evaluate your performance and outputs. ensure you have a formative assessment and get a
satisfactory result;
6. Then proceed to the next LG
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Information Sheet-1 Determining locations of leaks and isolate and dewater
1.1. Introduction to locations of leaks, isolate and dewaterring
Leaks can occur through valves that are malfunctioning, the largest losses of water are
through leaks in the water main itself, either where two sections are joined or where there is
a defect in the pipe. Proactive leakage control (where teams take action to prevent leaks
occurring) can bring several benefits. It will also lead to less disruption of traffic and daily life,
which happens when a leakage is discovered and has to be fixed. Less infrastructure
damage is caused and there is less risk of the mains water becoming contaminated
All fittings, couplings, saddles, sleeves, joints, straps, and fasteners having bolts, straps,
glands, set screws or other metal fasteners used for water main taps shall be protected from
corrosion after assembly and leak test (if applicable), as specified herein
There are different types of leaks, including service line leaks, and valve leaks, but in most
cases, the largest portion of unaccounted-for water is lost through leaks in supply lines.
Signs of underground leaks include:
Unusually wet spots in landscaped areas and/or water pooling on the ground surface
An area that is green, moldy, soft, or mossy surrounded by drier conditions.
A notable drop in water pressure/flow volume.
A sudden problem with rusty water or dirt or air in the water supply (there are other
causes for this besides a leak).
A portion of an irrigated area is suddenly brown/dead/dying when it used to be thriving
(water pressure is too low to enable distant heads to pop up properly).
Heaving or cracking of paved areas.
Sink holes or potholes.
Uneven floor grade or leaning of a structure.
Unexplained sudden increase in water use, consistently high water use, or water use
that has been
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1.2. Locating leaks
Various techniques exist for finding leaks through active detection. Some methods are better
suited to certain pipe materials and diameters, and whether the pipe has service connections
on it or not. The main techniques are briefly explained below, and recommendations for
methods to use are given in Table 15 and Table 16
A. Gas injection. In this method a gas detector is used to find the presence of a tracer gas
that has been injected into an emptied pipe. Hydrogen is the most common gas employed,
but helium can also be used. A probe is used along the route of the pipeline to detect gas
released through leaks in the pipe.
B. Manual listening stick. A stethoscope or listening stick with an earpiece is pressed
against fittings to listen for nearby leaks in the pipe.
Leak noise correlation. Leak noise correlator work by comparing the noise detected at two
different points on the pipeline. The times that a noise signal reaches the respective sensors
are used to estimate the location of the leak on a pipe. Noise correlator will also pick up non-
leak sources of noise, and thus the existence of a leak should be verified, for instance using
a ground microphone. Two types of noise correlator are used:
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C: Accelerometers. In this method, two accelerometer sensors are deployed on pipe
fittings on either side of the suspected leak position. This method is most effective on metallic
pipes.
D: Hydrophones. Leak location with accelerometers is harder in plastic pipes due to their
higher elasticity, and in large diameter pipes due to the higher diameter to wall thickness
ratios. Hydrophones are placed in contact with the water, for instance at hydrants, and pick
up the noise signal directly from the water.
E: In-line detection techniques.
These techniques are suitable for large diameter pipelines. Probes are placedin the pipe and
pick up leak noises as they pass through it. Tethered and free swimming systems are
available.
F: Leak noise loggers are placed on fittings and pick up the noise created by a leak in the
pipe.
Finding a precise leak location can be a difficult problem. If the leak is not visible on the
surface, leak detection equipment has to be used. The most common devices are an
acoustic (sound) detector and a leak noise correlator.
Fig leak noise correlator
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Figure Acoustic detection for leak locating with the listening stick
False leak noise: The problem with detecting leaks using the acoustic detection method is
that there are false sounds, such as noise and extraneous sounds that closely resemble leak
noise. In terms of how noise is generated, false leak noise is continuously generated by a
variety of noise sources, such as water flowing through pipes, tap water use, circuit noise
inducted from power cables, exciter frequency noise constantly generated by electric
transformers and fluorescent lights, motor noise and wind noise if the wind speed is 4 metres
per second or faster.
The challenge is to find the leaks, which will probably be underground, and repair
them as quickly as possible
1.3. Dewatering requirements
Dewatering is a practice where sediment-laden water is pumped into a compartmented
container, settling basin, filter, or other appropriate best management practice to trap and
retain sediment.
The selection of a dewatering practice is dependent upon the predominant soil texture
encountered at the dewatering site with consideration given to pumping rates, volumes and
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device effectiveness. Users of the practice of dewatering should be conscious of applicable
federal state, and local laws, rules, regulations, or permit requirements governing the use
and placement of dewatering
There are several different reasons why water pipes leak and they frequently occur in
combination.
Leakage occurs due to the pipelines:
being old and corroded, like the section shown in the figure
being poorly constructed, where sections of pipe are not joined properly to each other
being poorly maintained
having poor corrosion protection
being damaged through digging by other utilities
being damaged by aggressive (corrosive) water inside the pipe, when water quality
standards are
breached
being damaged through illegal connections made to the pipe
Foundation shifts - Small shifts in your home’s foundation (as it settles over time) can create
big adjustments in your water lines, causing them to disconnect or rupture.
High water pressure - High water pressure leads to damaging wear and tear on your pipes.
Water zipping through your pipes at high speeds increases the risk of your pipes bursting.
The sudden changes to the direction of water flow can be too much for your pipes to bear,
eventually resulting in leaks.
Tree roots - Tiny cracks in pipes can release water vapor into the surrounding soil, where
tree roots will take notice and burrow their way to your pipes, causing big problems.
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Corrosion - While not as big of a concern in some of Cincinnati’s newer neighborhoods,
many older homes in the area use copper or galvanized steel piping, which can be
susceptible to rust.
Temperature changes - Extreme changes in temperature (generally from cold weather) can
cause pipes to crack and begin leaking.
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Self-Check -1 Written Test
Directions: choose the best answer all the questions listed below. Use the Answer
sheet provided in the next page
A. choose the best answer for the following question (3pts each)
1. Which one of the following is a cause of pipe line leakag
A. being old and corroded
B. being poorly constructed, where sections of pipe are not joined properly to each other
C. being poorly maintained and having poor corrosion protection
D. being damaged through digging by other utilities
E. All f. none
2. Which one of the following methods is not indicator of leakage through a pipe?
A. Gas injection and Manual listening stick
B. Leak noise correlation
C. Accelerometers and Hydrophones
D. In-line detection techniques
E. All f. none
3.Signs of underground leaks include the following except
A. Unusually wet spots in landscaped areas and/or water pooling on the ground surface
B. An area that is green, moldy, soft, or mossy surrounded by drier conditions.
C. A notable drop in water pressure/flow volume.
D. A sudden problem with rusty water or dirt or air in the water supply (there are other
causes for this besides a leak).
E. All f. none
Note: Satisfactory rating – 4.5. And above points Unsatisfactory - below 4.5. Points
You can ask you teacher for the copy of the correct answers.
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Answer Sheet
Name: _________________________ Date: _______________
1._________
2._________
3._________
Score = ___________
Rating: ____________
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Information Sheet-2 Identifying and applying electrical safety procedures
1.1. Introduction
Your employees are your company’s most important asset, and you want to ensure that they
stay safe when doing any type of electrical testing, repair work, installation or maintenance.
During installation and replacement of water pipe line, if the technician have the condition to
do with electrical line/powers, selecting and applying the appropriate electrical safety
equipment is essential.
1.2. Electrical safety equipment
The purpose of wearing different types of electrical safety equipment is to protect the
technician’s health and their life against dangerous electrical hazards, such as arc flash. It is
the responsibility of the employer to properly analyze the workplace for potential hazards that
require electrical safety gear. If electrical safety hazards are present, then employers are to
ensure that the authorized employees are equipped with the appropriate electrical safety
gear. Employers are required to select the gear and communicate clearly why the selected
gear was chosen. Some of the electrical safety equipment which are important to protect the
electric hazards are:
Electrical Safety Gear – Head Protection
Hard hats are made to protect electrical workers from falling objects, flying objects, fixed
objects and electrical conductors. Electrical workers who have long hair are required to cover
it to prevent it from getting caught in mechanical parts such as chains and belts.
Electrical Safety Gear – Leg and Foot Protection
Safety shoes, leggings, and foot guards made from aluminized rayon, leather, and other
materials) help reduce the risk of serious injuries caused from sharp objects, molten metals,
electrical hazards, wet and slippery surfaces, hot surfaces and rolling or falling objects.
Electrical Safety Gear – Eye and Face Protection
Goggles and spectacles, special shields or helmets, face shields, and eye wear with side
shields can protect employees from electrical hazards, flying fragments, hot sparks and large
chips. Also, appropriate electrical safety gear can protect the eyes and face from optical
radiation, particles, dirt, mists, molten metal splashes, sand, glare and dust.
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Self-Check -1 Written Test
Directions: choose the best answer all the questions listed below. Use the Answer sheet
provided in the next page
I.choose the best answer for the following question (4pts each)
1. Which one of the following equipment is not include under electrical safety equipment?
A.Electrical Safety Gear (Head Protection)
B. Electrical Safety Gear (Leg and Foot Protection)
C. Electrical Safety Gear (Eye and Face Protection)
D.ALL
Note: Satisfactory rating – 2. And above points Unsatisfactory - below 2. Points
You can ask you teacher for the copy of the correct answers.
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Answer Sheet
Name: _________________________ Date: _______________
1.________
Score = ___________
Rating: ____________
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Information Sheet-3 Identifying and applying appropriate repair techniques
to maintain integrity of service
3.1. Introduction to maintenance of distribution System
Maintenance of a water distribution system is directed at the following general objectives:
To ensure adequate pressure in the system
To minimize non-revenue water (NRW);
To ensure that the water delivered is potable.
The distribution system consists of four components, whose O&M requirements are based
on their unique characteristics as well as their function and contribution to the total system.
They are:
Distribution pipelines,
Storage tanks or service reservoirs,
Service connections or standpipes,
Valves and other appurtenances.
Prevention is better than cure
When we install a service pipe, we check thoroughly to ensure there are no significant leaks
in the pipe work which is your responsibility.
It is known from experience that a great deal of Water can escape from undetected leaks in
domestic pipe work. So install the service pipe with appropriate quality of material and
workmanship so that the quality of installation is good.
There are a variety of managerial and technical ways to address the unaccounted-for water
problem. Managerial measures include the following:
Regular checks by caretakers or by alerts from consumers for pipeline damage, leakage
and illegal connections
Regular checks by the water point committee, caretakers and technicians on the quality and
leakage of connections (also the presence of illegal connections), meters (if present) and
taps
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3.2. Repairing leaking pipes
Leaks in water mains should be fixed as soon as they are detected. Once the leak is
pinpointed, the water in the isolated main must be removed. The repair job then consists of
sealing the leaks and/or replacing the defective pipe section.
The different methods of fixing leaks are as follows:
Using Epoxy (for Small Leaks)
Dry the surface of the area to be repaired,
File the surface to make it rough, and slightly enlarge the crack or hole,
Apply the epoxy, forcing some of it into the crack or hole to produce a seal,
Normally, the epoxy will set in 2 to 4 hours before the pipe can be disinfected and put back
into service, However, be sure to check the directions for use of the epoxy as some types
may require more or less time.
Using Sleeve Type Coupling /Repair Clamps
Put a split sleeve/repair clamp around the leak opening.
Using Strips from the Inner Tube (“Interior”) of a Rubber Tire
In emergency work when no other repair materials are available, cut a discarded inner tube
of a rubber tire into strips and wind the strong, flexible rubber strips tightly around the pipe to
cover the leak and its surrounding surfaces.
After the Leak is Repaired
Open the control valve to allow water to flow into the repaired section,
Observe carefully to verify if the leak is completely sealed,
After sealing, backfill the excavation and restore the surface to its former condition,
Apply the disinfection procedures.
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Self-Check -2
Written Test
Directions: choose the best answer all the questions listed below. Use the Answer sheet
provided in the next page
I. choose the best answer for the following question (3pts each)
1. Which one of the following is not the objective of maintenance for water distribution
system?
A. To ensure adequate pressure in the system
B. To minimize non-revenue water (NRW);
C. To ensure that the water delivered is potable.
D. All e. none
2. Operation and maintenance requirements are based on the following except
A. their unique characteristics the system
B. their function
C. contribution to the total system
D. all e. none
3. Which one of the following is not the method of fixing leaks
A. Using Epoxy (for Small Leaks)
B. Using Sleeve Type Coupling /Repair Clamps
C. Using Strips from the Inner Tube (“Interior”) of a Rubber Tire
D. All E. none
Note: Satisfactory rating – 4.5 and above points Unsatisfactory - below 4.5.points
You can ask you teacher for the copy of the correct answers.
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Answer Sheet
Name: _________________________ Date: _______________
1. __________
2. __________
3. __________
Score = ___________
Rating: ____________
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Operation Sheet -1 Techniques for repairing a leak of service pipe
Activity 1. Steps to repair leak service pipe
1. Locate the failure from an external sign such as a water jet or wet area of soil, or from
specialized leak detection equipment.
2. Select appropriate PPE and tools and equipment
3. Assess the damage to the pipework and identify the problem
4. Identify the resources (human, time and materials) needed to rectify the problem.
5. Mobiliser resources.
6. Let customers know about the extent of the damage and the time needed to solve
the problem.
7. Provide an alternative water supply until the restoration work has been completed.
8. Close isolation valves in the system to isolate the leak.
9. Ensure that the work area is safe for working using appropriate signs, barriers and traffic
diversion measures
10. Excavate the failed pipe section while ensuring worker safety and avoiding further damage to
the pipe.
11. Use an extractor pump capable of handling sludge to drain water from the trench.
12. Repair the failed pipe using an appropriate method:
13. For a small leak, a repair clamp may be fixed over the leak to seal it. Small leaks in steel pipe
may be welded closed.
For a more extensive leak, the damaged section of pipe is cut out, a new section of pipe
installed using appropriate connectors. PVC is often used for the replacement section and
special fittings are available to connect PVC to other pipe materials. Note that AC pipes
should not be cut – rather replace a whole length of pipe.
Replace a whole length of pipe if damage is extensive or it is clear that the pipe is bad
condition and likely to fail again.
14. In all cases, ensure that exposed and new sections of pipe are carefully cleaned and
Disinfected.
Take special care to ensure that any solids that may have entered the pipe during the repair
are removed.
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15. Slowly open one or more of the closed isolation valves as well as a hydrant or valve to allow
air to escape from the system.
16. Ensure that all isolation and scour valves opened or closed are reinstated to their correct
state
17. Flush the section using a hydrant to ensure that any contaminants and solids are removed.
18. . Once the section is under pressure, inspect the repairs for leaks.
19. Reinstate the pipe bedding, blanket and backfill using appropriate placing and compaction
methods and materials.
20. Reinstate and clean the area where the excavations were done.
21. Complete a pipe repair report, including an analysis of the likely cause of the failure.
Activity 2. Repair of Globe Valves, Public Faucets and Other Related Valves
a) Tools Needed:
1. Flat jawed or monkey wrench (large enough to fit the packing nut of the
Valve/faucet)
2. Rubber sheet or soft cloth (to protect the finish of the faucet or packing nut)
3. Screw driver
4. Faucet seat dresser.
b) Materials Needed:
1. New faucet washer or valve seat and disc,
2. Lubricated candle wick for stem packing,
3. Waterproof grease,
4. Washer screws.
Steps
1. Familiarize yourself with the different parts of the faucet or valve,
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2. Examine and find out the location of the leak. If water is coming out from the mouth or
outlets, the trouble is due to a damaged washer or damaged seat or both. If water is coming
out from around the stem when the valve is open, the stem packing is defective,
3. Close the control valve to cut off water supply to the defective valve/faucet,
4. Open the packing nut with a wrench. Place a piece of rubber sheet or cloth over the wrench
jaws to avoid marring t he valve/faucet finish,
5. Repair the defective valve/faucet,
6. Replace the handle and tighten the handle screw,
7. Turn on water supply and observe for leaks
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Name: _____________________________ Date: ________________
Time started: ________________________ Time finished: ________________
Instructions: Given necessary templates, tools and materials you are required to perform
the following tasks within --- hour.
Activity 1. Repair for leak service pipe
Activity 2. Repair for Globe Valves, Public Faucets and other related valves
LAP Test Practical Demonstration
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Instruction Sheet Learning Guide #- 31
This learning guide is developed to provide you the necessary information regarding the
following content coverage and topics –
Applying test or operational pressures to service and all joints.
Checking pipes, connections and fittings are operable without leakage under test or
operational conditions.
This guide will also assist you to attain the learning outcome stated in the cover page.
Specifically, upon completion of this Learning Guide, you will be able to
Apply test or operational pressures to service and all joints.
Check pipes, connections and fittings are operable without leakage under test or operational
conditions
Learning instruction
1. Read the specific objectives of this Learning Guide.
2. Follow the instructions described below 3 to 6.
3. Read the information written in the information “Sheet 1 and Sheet 2,” from page (209 and
214) and Accomplish the “Self-check 1, and Self-check 2, ” in page 213 and 215
respectively.
4. If you earned a satisfactory evaluation proceed to “Operation Sheet 1 and 2in page 217
5. Then accomplish LAP Tests,”1, and 2, in page 219 (if you are ready). Request your teacher
to evaluate your performance and outputs. ensure you have a formative assessment and get
a satisfactory result;
6. Then proceed to the next LG
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Information Sheet-1 Applying test or operational pressures to service and
all joints
1.1. Introduction pressure testing
Pressure tests are performed to ensure the safety, reliability, and leak tightness of pressure
systems. A pressure test is required for a new pressure system before use or an existing
pressure system after repair or alteration. There are two methods for pressure tests:
hydrostatic and pneumatic. A hydrostatic test is performed by using water as the test
medium, whereas a pneumatic test uses air, nitrogen, or any non-flammable and nontoxic
gas
As soon as the pipe laying is completed, a hydraulic test has to be carried out to check the
quality of workmanship, namely:
the mechanical strength and leak tightness of the system,
the strength of the anchorage and support structures
work site safety .
All changes of directions, fittings and valves should be permanently anchored before the test
starts. The ends of the tested section must be securely closed and temporarily anchored as
well. There must be sufficient backfilling to prevent movement of the pipes during the test,
but the joints should be left exposed until testing has been completed.
1.2. Testing approach
Water mains can be tested in lengths varying from a few hundred metres up to about a
kilometer; although possible in theory, in practice it is more difficult to detect leaks with
distances of more than 500 m.
It is sometimes possible or desirable to carry out a double test, first on shorter and later on
longer sections.
The test pressure applied depends on the regulations.
For distribution systems, it is usually 50 % higher than the maximum working pressure.
1.3. Pipe Testing
Pipes will have been tested prior to leaving the factory and should also be tested after
reaching the site in order to check for possible damage resulting from transportation.
A final check is necessary for each pipe before it is put into position
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1.4. Piping Pressure Test
Depending on the system specification the finished installation must satisfy one or both of the
following tests.
Hydrostatic Test
Pneumatic test
Hydrostatic Test
Pipeline Hydrostatic testing is a vital procedure in both pipeline construction and pipeline
maintenance. Before new pipeline runs go into operation, it is necessary to make sure they
are correctly commissioned for their purposed use. Also, proper maintenance of pipelines
requires that any pipeline susceptible to failing and leaking be caught during controlled
testing procedures, not while fuels and other chemicals may be flowing through the pipes.
You can observe the water leakage in the picture given below (Figure 1). This leakage took
place because of the crevices in the pipeline. It either stops the transfer of water from one
place to another or reduces the pressure to a great extent. So, to gauge the strength,
performance, and durability of a pipeline, it is necessary to perform hydrostatic testing of the
pipe.
Pipeline hydrostatic pressure testing is performed by charging the pipeline and then shutting
off the supply valve for documenting observations about the pressure loss. This hydrostatic
test is a pre-commissioning and non-destructive test or quality control procedure which
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Authenticates the integrity of the pipeline and the fabrication, as well as the welding and joint
jobs performed on it.
PIPELINE HYDROSTATIC TESTING EQUIPMENT
Pipeline hydrostatic testing equipment should be preplanned and readied before the testing
job date arrives. Pressure testing on any vessel will entail the availability of essential
equipment. Here is the list of pipeline hydrostatic pressure testing equipment:
Pump, Valves, Couplings and Pressure Gauge – A pump which is capable of generating
the specified design pressure of the pipeline is required for hydro-testing. The motor of the
pump should have the power to generate the design pressure. However, the rating of the
pump will be dependent on the pipe under observation and at what pressure it will be
routinely operated. The setup should have a pressure gauge for measuring the pressure
inside the pipe. The type of valve used varies as per the size of the pipeline. Couplings
should be used to connect pipes in a best possible manner to eradicate any pressure drops.
Section of pipe passing through clean or sensitive areas may be checked for leaks using a
low-pressure air test prior to undergoing a hydrostatic test if requested by the client.
Pipeline systems shall be pressure tested to 1.5 times their design pressure unless otherwise
agreed with the client or his nominated representative.
The test pressure when reached will be maintained for a minimum of 1 hour (or longer if
required by the system specification).
The test fluid for hydrostatic tests shall be clean potable water (unless otherwise specified) at
ambient temperature, which shall contain no substances which could be detrimental to the
material or the process.
Fill the piping system with water and apply a preliminary test pressure of 1 Bar, or as directed
by the Project Engineer. While holding this pressure, vent all remaining air from the piping
system at the high point vents and continue to fill with water as necessary to maintain a 1 bar
initial fill pressure.
Note This pressure should be held for a minimum of 10 minutes to allow for the walk down of
the system and the location of any major leaks. If leaks are detected during this step, or at
any time during the test, relieve the pressure and take appropriate action to correct the leak.
If necessary, consult the Project Engineer for instruction.
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Apply the hydrostatic test pressure in increments of 1 Bar, or as directed by the Project
Engineer, until the maximum test pressure is reached. Hold pressure for 5 minutes at each
1Bar increment and inspect for leaks before adding more pressure.
The system shall be monitored to ensure that the desired pressure (to within 0.1 Bar) is
achieved and that allowances are made for thermal expansion and contraction of the system.
Note: It is very important to allow for thermal equalization before starting the 1 hour test
period. Cooling of the test fluid will cause it to contract and therefore the pressure in the
system will fall without any leak in the system.
Hold the maximum test pressure for 1 hour and get the client to witness it and sign the
necessary documentation.
Note the specification should indicate allowable test tolerances which are permissible to
account for thermal differences and the size of a piping system under test.
Upon successful completion of the test, the system shall be vented slowly, drained and all
end points blanked and capped
Pneumatic Test
Pneumatic tests are potentially more dangerous than hydrostatic because of the higher level
of potential energy. Pneumatic tests may be performed only when at least one of the
following conditions exists:
When pressure systems are so designed that they cannot be filled with water.
When pressure systems are to be used in services where traces of the testing medium
cannot be tolerated. Using a pneumatic test instead of hydrostatic requires approval by the
pressure systems program manager. In addition to a justification, a piping schematic for
pneumatic pressure test is required. A recommended typical piping schematic for pneumatic
test is shown in Figure
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Important Installation of a pressure relief valve is required for a pneumatic test.
The test fluid for pneumatic tests shall be clean dry air unless otherwise agreed with the
client or his nominated representative.
Apply a preliminary test pressure of 1 Bar, or as directed by the Project Engineer.
Note This pressure should be held for a minimum of 10 minutes to allow for the location of
any major leaks. If leaks are detected during this step, or at any time during the test, relieve
the pressure and take appropriate action to correct the leak. If necessary, consult the Project
Engineer for instruction.
Apply the test pressure in increments of 0.5 Bar, or as directed by the Project Engineer, until
the maximum test pressure is reached. Hold pressure for 5 minutes at each 0.5 Bar
increment to allow the system to equalise strains and to test joints with a soapy water
solution before adding more pressure.
Enough time will be left between steps.
Note: The maximum test pressure shall be 1.5 times the maximum system operating
pressure. For systems that derive their pressure from hydrostatic pressure, the required test
pressure will be verified prior to testing by the Project Engineer or the Field Engineer.
Hold the maximum test pressure for 1 hour and get the client to witness it.
Remove the pressure, with caution to avoid escaping air stream, debris, and high decibel
noise level.
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Self-Check -1
Written Test
Directions: choose the best answer all the questions listed below. Use the Answer sheet
provided in the next page
I. choose the best answer for the following question (3pts each)
1. Which one of the following statements is the Testing approach of water pipe line
pressure?
A. Water mains can be tested in lengths varying from a few hundred metres up to about a
kilometer;
B. It is sometimes possible or desirable to carry out a double test, first on shorter and later on
longer sections.
C. The test pressure applied depends on the regulations.
D. For distribution systems, it is usually 50 % higher than the maximum working pressure.
E. All F. None
2. As soon as the pipe laying is completed, a hydraulic test has to be carried out to check the
quality of workmanship by the following except
a. the mechanical strength and leak tightness of the system
b. the strength of the anchorage and support structures C. work site safety D. all E.none
3. Which one of the following statements is true about Pipe Testing?
A. Pipes will have been tested prior to leaving the factory
B. Pipe will have been tested after reaching the site in order to check for possible damage
resulting from transportation.
C. A final check is necessary for each pipe before it is put into position D.All E. none
4. Pneumatic tests may be performed only when at least one of the following conditions
exists:
A. When pressure systems are so designed that they cannot be filled with water.
B. When pressure systems are to be used in services where traces of the testing medium
cannot be tolerated.
C. Important Installation of a pressure relief valve is required for a pneumatic test.
D. The test fluid for pneumatic tests shall be clean dry air unless otherwise agreed with the
client or his nominated representative. E.All F. N
Note: Satisfactory rating – 6 and above points Unsatisfactory - below 6.points
You can ask you teacher for the copy of the correct answers.
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Answer Sheet
Name: _________________________ Date: _______________
1. __________
2. ___________
3. ____________
4. ____________
Score = ___________
Rating: ____________
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Information Sheet-2 Checking pipes, connections and fittings are operable
without leakage under test or operational conditions
1.1. Introduction to checking to pipe connection and fitting
After applying pressure test all installed service pipes, fitting and other connections should be
checked for leaks and compliance with agreed specification to avoid wastage and
contamination of service pipe. Proper maintenance and checking of operational condition of
service pipe pressure which leads to extend the life of the system and reduce damage of
different fitting and different accessories of the pipe lining system.
Operation condition
Appropriate temperature and pressure ratings are needed for proper operating conditions.
Operating pressure range is the working range of pressures or the pressure ratings at
which the fitting was designed to operate, typically measured in pounds per square inch (psi).
Operating above or below this rating could cause the fitting to fail (i.e. break, leak, lose its
seal).
Operating temperature range is the working range of temperatures or the temperature
ratings at which the fitting was designed to operate, measured in degrees Fahrenheit (°F) or
degrees Celsius (°C). Operating above or below this rating could cause the fitting to fail.
1.2Ensuring system hygiene and operational performance
To ensure system hygiene and operational performance disinfection is important the purpose
of disinfection is to destroy pathogens (harmful microorganisms) which may be present in the
water service pipe after completion of work.
1.3 Applying OHS procedures and Personal work site safety
The following OHS procedures should be conducted while service pipe installation
Work in well-ventilated area
Never work in small confined spaces without the buddy system, and without the guidance of
an authorized, qualified instructor or supervisor.
Use air-purifying respirators if ventilation is inadequate.
Fire - Use CO2, dry chemical, or foam to fight fire.
Always wear safety equipment
Follow safety signs.
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Self-Check -2
Written Test
Directions: choose the best answer all the questions listed below. Use the Answer sheet
provided in the next page
I. choose the best answer for the following question (3pts each)
1. Which one of the following is not the objective of checking connection and fitting of service
pipe operational condition?
A. Avoid wastage resource and leak of water t
B. To reduce contamination of water through the pipe line
C. To increase the life of the system
D. All e. none
2. Which type of OHS procedures should be conducted while service pipe installation
Work in well-ventilated area
A. Use air-purifying respirators if ventilation is inadequate.
B. Fire - Use CO2, dry chemical, or foam to fight fire.
C. Always wear safety equipment
D. Follow safety signs. E. All F.none
Note: Satisfactory rating – 6 and above points Unsatisfactory - below 6. Points
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Answer Sheet
Name: _________________________ Date: _______________
1. __________
2.____________
Score = ___________
Rating: ____________
You can ask you teacher for the copy of the correct answers.
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Operation Sheet -1 Testing for service pipe pressure operation by
hydrostatic method
Testing procedure for service pipe pressure
1. Starts by filling the section with chlorinated water, if possible, from the lower of the two pipe
ends. The air should be completely removed from pipe before it is pressurized.
2. After filling, the section should be left under moderate pressure until stable conditions are
achieved, depending on the absorption of pipe material. For absorbent pipes such as AC and
concrete or cement-lined pipes, it can take a couple of days before the pipe material is fully
saturated.
3. The pressure is then brought up to the test value by a hand operated pump and all exposed
parts of the section are examined for water tightness. The duration of the test and
interpretation of the results depend on regulations.
4. After hydraulic test has been successfully completed, the pipeline should be flushed out to
remove any remaining debris and properly disinfected.
5. The British regulations prescribe a chlorine disinfection applied in a dose sufficient to
maintain a residual of 20-30 mg/l, which must stand for at least 16 hours (Brandon,1984).
6. Before being washed out, the water in the pipeline must be de-chlorinated. After washing out,
the network can be charged by water, and after testing of the water quality, it can be put into
service.
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Operation Sheet 2 Testing service pipe pressure by pneumatic method
Steps for pneumatic pressure test service pipe
1. Ensures the pressure gauges used have current calibration stickers
2. Removes all persons not directly involved with the test from the immediate testArea
3. Removes pressure relief valves or non-reclosing relief device from the vessel or test
boundary where the test pressure will exceed the set pressure of the valve OR Holds down
each valve by means of an appropriate test clamp and pressurizes both sides of non-
reclosing relief devices Installs temporary, higher-rated devices where practical
4. Installs the calibrated test gauge so it is visible at all times
5. Ensures the skillet blanks or test plugs or clamps are appropriate for use and are free of
obvious defects
6. Fills and vents system as necessary to remove as much air as practical
7. Ensures that water used for the test is at not less than ambient temperature, but in no case
less than 70°F
8. Pressurizes the system, raising the pressure in the system gradually until the designated test
pressure is achieved
9. Maintains this test pressure for 10 minutes before inspection. Then, if test is above maximum
allowable working pressure (MAWP), reduces to MAWP while making a full thorough
inspection for leaks.
10. Ensures the metal temperature at the time of the hydrostatic test does not exceed 120°F
11. If there is evidence of structural distortion, either rejects the system or repairs as advised by
the inspector
12. If there is leakage in the system, performs the following as appropriate:
Ensure repairs is performed and returns to Step 12 or
Rejects the system
13. When the test is completed, vents the test pressure to atmosphere and returns relief devices
to normal configuration
14. Signs pressure test record
15. Completes pressure test record and submits copy to the pressure systems program manager
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Name: _____________________________ Date: ________________
Time started: ________________________ Time finished: ________________
Instructions: Given necessary templates, tools and materials you are required to perform
the following tasks within --- hour.
Task1. Test service pipe pressure operation by hydrostatic method
Task2. Test service pipe pressure operation by pneumatic testing method
LAP Test Practical Demonstration
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Instruction Sheet Learning Guide #- 32
This learning guide is developed to provide you the necessary information regarding the
following content coverage and topics –
Checking, maintaining and storing equipment, tools and materials
Restoring work site
Completing workplace records
This guide will also assist you to attain the learning outcome stated in the cover page.
Specifically, upon completion of this Learning Guide, you will be able to
Check, maintain and store equipment, tools and materials according to manufacturer
guidelines and organizational procedures.
Restore work site to meet environmental and organizational requirements.
Complete workplace records and process as required.
Learning instruction
1. Read the specific objectives of this Learning Guide.
2. Follow the instructions described below 3 to 6.
3. Read the information written in the information “Sheet , Sheet 2, and sheet 3”from page
223,228 and 230 and Accomplish the “Self-check 1,Self-check 2 and self-check 3” in page
226, 229and 232 respectively.
4. If you earned a satisfactory evaluation proceed to “Operation Sheet 1,2” in page 233
5. Then accomplish LAP Tests,”1,2, in page 234(if you are ready). Request your teacher to
evaluate your performance and outputs. ensure you have a formative assessment and get a
satisfactory result;
6. Then proceed to the next LG
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Information Sheet-1 Checking, maintaining and storing equipment, tools
and materials
1.1. Introduction to maintenance tools and equipment
The main aim of Checking and maintaining of tools and equipment which used for pipe
installation and pipe itself to avoid Further damage to the pipe is possible during the process
of unloading, stacking and/or stringing along the laying route. Each scratch on the external or
internal coating of a metal pipe is a potential source of corrosion. Scratch on Plastic pipes
reduce the pipe strength and may be the point of leakage.
Materials required in construction operations shall be stored, and handled in a manner to
prevent deterioration and damage to the materials, ensure safety of workmen in handling
operations and non-interference with public life including safety of public, prevention of
damage to public property and natural environment. Materials shall be stored and placed so
as not to endanger the public, the workers or the adjoining property. Materials shall be
stacked on well -drained, flat and unyielding surface. Material stacks shall not impose any
undue stresses on walls or other structures. Materials shall be separated according to kind,
size and length and placed in neat, orderly piles. High piles shall be staggered back at
suitable intervals in height. Piles of materials shall be arranged so as to allow a minimum 800
mm wide passageway in between for inspection and removal. All passageways shall be kept
clear of dry vegetation, greasy substance and debris. For any site, there should be proper
planning of the layout for stacking and storage of different materials, components and
equipment’s with proper access and proper maneuverability of the vehicles carrying the
material. While planning the layout, the requirements of various materials, components and
equipment’s at different stages of construction shall be considered. We must always be
aware that maintenance tasks themselves are potentially hazardous and can result in injury.
The successful maintenance program should be
well organized and scheduled,
controls hazards,
defines operational procedures, and
Trains key personnel.
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Storage Requirement by Classification of Materials
Stored materials shall be separately stored under following classifications, with
appropriate care necessary precautions to each Classification:
Climatically Sensitive Materials
Durable Materials
Materials Vulnerable to Rough Handling
Inflammable and/or Fire Sensitive Materials e) Hazardous Materials
1.2. Clean work equipment
Assess suitability of equipment for cleaning
Select appropriate cleaning equipment and chemicals
Select the protective clothing and equipment to be used
Prepare equipment for cleaning that has been used
Clean equipment as identified
Undertaking basic preventative maintenance and basic repairs on equipment
Tidy work site
Dispose of waste
Clean, check and store cleaning equipment and chemicals
Storing equipment in accordance with enterprise requirements
Storing chemicals in accordance with legislated requirements
Replenishing consumables.
Reporting issues that need to be addressed by other personnel, including internal and
external personnel.
1.3. Clean work areas
Assess area to be cleaned
Select appropriate cleaning equipment and chemicals
Select the protective clothing and equipment to be used
Prepare the area
Undertake the selected cleaning process
Dispose of waste
Return area to operational condition
Clean, check and store cleaning equipment and chemicals
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1.4. Maintain work areas and equipment
Identify maintenance tasks to be undertaken
Perform maintenance tasks, as required
Report problems and faults that require additional attention
Store maintenance items and equipment
Perform required administrative tasks
Assist in special projects, where required
1.5. Pipe cleaning and disinfection
Corrosion deposits in pipes or sediments caused by improper treatment have to be
removed to prevent water quality deterioration. Three techniques commonly used are
flushing, swabbing and air scouring. These techniques may greatly help to improve the
water quality but additional maintenance equipment has to be employed. Moreover, the
network layout needs to include a number of hydrants or washouts to connect this
equipmentOperation.
Appropriate temperature and pressure ratings are needed for proper operating conditions.
Operating pressure range is the working range of pressures or the pressure ratings at
which the fitting was designed to operate, typically measured in pounds per square inch
(psi). Operating above or below this rating could cause the fitting to fail (i.e. break, leak,
lose its seal).
Operating temperature range is the working range of temperatures or the temperature
ratings at which the fitting was designed to operate, measured in degrees Fahrenheit (°F)
or degrees Celsius (°C). Operating above or below this rating could cause the fitting to fail.
Page 230 of 242
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Version1 September 2020
Self-Check -1
Written Test
Directions: choose the best answer all the questions listed below. Use the Answer sheet
provided in the next page
I. Choose the best answer for the following question (2pts each)
1. All tools, equipment and vehicles must be properly maintained so that workers are not endangered.
A. True B. false
2. Which one of the following is not characteristics successful maintenance program should?
A. well organized and scheduled,
B. controls hazards,
C. defines operational procedures, and
D. Trains key personnel.
E. All F. None
1. From the given alternative which one is not true about Clean work equipment
A. Assess suitability of equipment for cleaning and Select appropriate cleaning
equipment and chemicals
B. Select the protective clothing and equipment to be used
C. Prepare equipment for cleaning that has been used
D. Clean equipment as identified and Clean, check and store cleaning equipment and
chemicals
E. All F. None
Note: Satisfactory rating – 4 and above points Unsatisfactory - below 4. Points
You can ask you teacher for the copy of the correct answers.
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Answer Sheet
Name: _________________________ Date: _______________
1.__________
2.__________
3.___________
Score = _______
Rating: ______
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Version1 September 2020
Information Sheet-2 Restoring Work site
1.1. Introduction to restore work site
While work is completed work site should be restored, place back to the original position:
All pieces of pipe, extra fittings, tools, and incidental materials, including rubbish and excess
spoil material, should be removed from the site.
Damaged areas should be replaced according to local specifications and standards.
Perform required administrative tasks
Flushing cleaning chemicals from areas
Capturing waste created as part of the cleaning process
Compliance with local legislation and regulations
Replacing items that were moved back into original position
Replacing items into designated positions as identified by work orders
Removing barriers and signage
Notifying relevant supervisors of operational readiness of area
Alignment with enterprise policies and procedures
Report problems and faults that require additional attention
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Self-Check -1
Written Test
Directions: choose the best answer all the questions listed below. Use the Answer sheet
provided in the next page
I.choose the best answer for the following question (4pts each)
1. Which one of the following is not true about restore work site?
A. Removing barriers and signage
B. Replacing items into designated positions as identified by work orders
C. Replacing items that were moved back into original position
D. Flushing cleaning chemicals from areas
Note: Satisfactory rating – 2and above points Unsatisfactory - below 2. Points
You can ask you teacher for the copy of the correct answers.
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Answer Sheet
Name: _________________________ Date: ______________
1. _______
2. _______
Score = ___________
Rating: ____________
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Information Sheet-3 Completing workplace records
3.1. Introduction to Record and Report
A record system has to be developed which should be realistic and apply to the operating
problems involved at the particular transmission, distribution and service reservoir sites. The
most efficient way to keep records is to plan what data is essential and then prepare the
formats followed by the persons to fill the data, frequency and to whom the record is to be
sent for review and report. Sample records to be maintained at transmission, distribution and
service reservoir sites are given below for guidance. The following details shall be recorded:
Transmission line
Updated transmission system maps with alignment plans. Longitudinal sectional plans,
Record of daily readings of flow meter at upstream and downstream end of pipeline,
Record of water level of reservoir at both upstream and downstream end of transmission
system.
Pressure reading of the transmission system.
Identification of persistent low-pressure location along the pipeline.
Record of age of pipes.
Identify pipelines to be replaced.
Identify source of leaks.
Record of Bulk meter/water meter reading before the delivery into overhead tank.
Record of residual chlorine.
Record on when the pipeline leaks were repaired or pipe changed and the cost of materials
and labor cost thereof.
Service Reservoir
Water levels in the reservoir,
Time and relevant operation of control valves with time of opening and closure or throttling
position of the valves,
Daily flow meter readings both on the inlets and outlets,
At least one a day Residual chlorine readings of inflow water and outflow water,
Gland ropes of the valves/Spares at the SR were changed,
Manhole covers were changed / replaced,
Water level indicator was repaired or replaced,
Reservoir was cleaned,
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Out-fall drain for scour and overflow was last cleaned,
Ladder was changed, when the structure of the reservoir was last repaired to attend to
structural defects or arrest leakage,
Reservoir/Pips was last painted,
Total cost of repairs and replacements at the SR in previous year along with breakup of,
material cost and labor cost with amount spent on outside agencies for repairs and,
replacements.
Distribution Lines
Updated system map,
Pressure and flow readings at selected monitoring points,
Persistent low pressure or negative pressure areas,
Age of pipes/quality of pipes,
Pipelines to be replaced,
Presence of undesirable materials,
Water budget for each zone served by one SR,
Number of connections given,
Number of meters out of order,
Quantity measured at outlet of reservoir, Quantity distributed/measured or billed, 12. Water
budget for each zone served by one SR
Source of leaks and persistent leak points,
Status of bulk meters - functioning or not,
Status of consumer meters,
Facilities for repairs of consumer meters,
Number of unauthorized connections,
Residual chlorine levels at the pre-selected monitoring points,
Bacteriological quality of the water sampling points,
Record of carrying out repairs on the following
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Version1 September 2020
Self-check -3 Written test
Directions: choose the best answer all the questions listed below. Use the Answer sheet
provided in the next page
I. choose the best answer for the following question (4pts each)
1. A record system has to be developed which should be realistic and apply to the operating
problems involved at the particular,
A. transmission
B. service reservoir
C. distribution
D. all
2. Which one of the following data records from distribution line after the work is completed?
A. Updated system map,
B. Pressure and flow readings at selected monitoring points,
C. Persistent low pressure or negative pressure areas,
D. Age of pipes/quality of pipes,
E. Pipelines to be replaced,
3. Data record from transmission line after completion of the work
A. Identification of persistent low-pressure location along the pipeline.
B. Record of age of pipes and Identify pipelines to be replaced.
C. Identify source of leaks and Record of Bulk meter/water meter reading before the delivery
into overhead tank.
D. Record of residual chlorine E. all f. none
Note: Satisfactory rating – 3 and above points Unsatisfactory - below 3points
You can ask you teacher for the copy of the correct answers.
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Version1 September 2020
Answer Sheet
Name: _________________________ Date: ______________
1.__________
2._________
3._________
Score = ___________
Rating: ____________
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Version1 September 2020
Operation Sheet -1 Technique of Storing pipe installation tools and equipment’s
Steps to Store pipe installation Tools & Equipment
Step 1: Use and wear appropriate PPE
Step 2: Select appropriate tools and equipment
Step 3: Create appropriate room to store each tools and equipment
Step 4: Clean out the junk and clutter and make a space only for tools
Step 5: Sort each tool and equipment’s
Step 6: Clean out dirt and debris from tools from the tools and equipment’s
Step 7: Store tools and equipment’s properly
Page 240 of 242
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Operation Sheet -2 Cleaning for water mains or service pipe lines by chlorination
Procedures for Chlorination of Water Mains
1. Select appropriate tools and equipment
2. Select appropriate tools and equipment
3. Inform the area 48 hours prior to test.
4. Ensure that all boundary valves are closed.
5. Open hydrant, service or test port to discharge water as chlorinated water is being fed
through main.
6. Feed chlorinated water at the desired concentration into the water main.
7. Check that chlorinated water has reached all sections of the main to be disinfected by
flushing and testing chlorine residual at each hydrant using an approved field kit.
8. Operate all valves in test section to thoroughly disinfect all appurtenances.
9. Once water main has been thoroughly chlorinated as approved by the consultant or the area,
wait a minimum of 12 hours for residual test.
10. Residual chlorine tests are to be taken at a minimum of 2 locations along the main, at every
hydrant and must be at least 0.2mg/l after 12 hours.
11. De-chlorination must be done no longer than 24 hours after chlorination.
12. The contractor must determine how chlorinated water is to be neutralized or disposed and
ensure this procedure is acceptable to the area. Under no circumstances will chlorinated
water be allowed to be discharged into a sewer system or near a water course.
13. Once de-chlorination is done; low concentration test strips are to be used to confirm that
chlorinated water has been flushed out of the mains
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Name: _____________________________ Date: ________________
Time started: ________________________ Time finished: ________________
Instructions: Given necessary templates, tools and materials you are required to perform the
following tasks within --- hour.
Task1. Store pipe installation tools and equipment’s
Task2. Clean for water mains or service pipe lines by chlorination
LAP Test Practical Demonstration
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Reference
1. SLAC Environment, Safety, and Health Manual (SLAC-I-720-0A29Z-001)
Chapter 14, “Pressure Systems”
2. Pressure Systems: Installation, Inspection, Maintenance, and Repair Requirements
(SLAC-I-730- 0A21S-053)
Chapter 51, “Control of Hazardous Energy”
3. American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code
(BPVC), 2015 (ASME BPVC-2015)
4. ASME Pressure Piping Code, including applicable addenda and code cases
5. ASME B31.1-2014, “Power Piping” (ASME B31.1-2014)
6. ASME B31.3-2014, “Process Piping” (ASME B31.3-2014)
7. ASME B31.9-2014, “Building Services Piping” (ASME B31.9-2014)
8. National Board of Boiler and Pressure Vessel Inspectors (NBBI)
9. NB 23-2015, National Board Inspection Code (NBIC) (NBBI NB 23-2015)
10. Brandon, T.W. (1984). Water distribution systems. (Water practice manuals; no. 4).
London, UK, Institution of Water Engineers and Scientists (IWES)
11. Mays, L.W. (2000). Water distribution systems handbook. New York, USA, McGraw-Hill.
12. http://inspectapedia.com/plumbing/Plastic_Pipes.htm
13. http://flange-fitting.com/
14. TK Corporation http://www.tkbend.co.kr/
15. Steel Tube India http://www.steeltubesindia.net/
16. 16. Acker C, Kraska D (2001). Operation and maintenance of water distribution systems
during and after conversion to chloramine disinfection. In: Proceedings of the AWWA
Annual Conference. Denver (CO): American Water Works Association.