hot tapping requirement

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Hot Tapping Requirement

Prepared by Eng. Wael Elariny

Course contents

Module 11. Pipes2. Flanges3. Fitting and branch connections4. GasketsModule 21. Types of welding processes2. Welding symbols3. Welding electrodes identifications4. Welding procedure specifications5. Welding Discontinuities6. Introduction to non destructive testModule 31. Hot tapping Requirements.Module 41. Hot tapping Simulation.

Module 11. Pipes2. Flanges3. Fitting and branch connections4. GasketsModule 21. Types of welding processes2. Welding symbols3. Welding electrodes identifications4. Welding procedure specifications5. Welding Discontinuities6. Introduction to non destructive testModule 31. Hot tapping Requirements.Module 41. Hot tapping Simulation.

MODULE 1PIPING

1- Pipeline specification.

Piping is an assembly of components that includepipe, valves, fitting ,flanges, bolts, gaskets andsupports used to convey distribute and control flowof fluid.

Piping must also contain the conveyed fluid andaccommodate internally and externally imposedloads and thermal movements.

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Piping is an assembly of components that includepipe, valves, fitting ,flanges, bolts, gaskets andsupports used to convey distribute and control flowof fluid.

Piping must also contain the conveyed fluid andaccommodate internally and externally imposedloads and thermal movements.

Materials .

1. Carbon steels: used for normal corrosion conditions within atemperature range of -29 °C to 426 °C.

example: ASTM A 106-GR.B

2. Killed carbon steels: used for corrosion conditions within a temperaturerange of -29 °C to -46 °C.

example: ASTM A333-GR.6

3. Alloy steels: used for higher temperature and higher corrosion rates.

example: ASTM A335-P9 (9cr – 1 mo)

4. Stainless steels: groups of steels having a minimum of 10.5%chromiumused for excessive corrosion conditions.

example: ASTM A312-TP 316L (18cr-8Ni-2mo)

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1. Carbon steels: used for normal corrosion conditions within atemperature range of -29 °C to 426 °C.

example: ASTM A 106-GR.B

2. Killed carbon steels: used for corrosion conditions within a temperaturerange of -29 °C to -46 °C.

example: ASTM A333-GR.6

3. Alloy steels: used for higher temperature and higher corrosion rates.

example: ASTM A335-P9 (9cr – 1 mo)

4. Stainless steels: groups of steels having a minimum of 10.5%chromiumused for excessive corrosion conditions.

example: ASTM A312-TP 316L (18cr-8Ni-2mo)

Materials

5. Cast irons: used for underground utilities, sewers and process drainagesystems.

example: grey cast iron, ductile iron.

6. Non metallic: used for better corrosion resistance at low pressure andnormal temperature conditions. Limited to a maximum temperature of100°C.

example: GRP (glass reinforced plastic) – polyethylene.

7. Plastic lined: Used for chemical resistance, limited to maximum servicetemperature of 100°C.

8. Cement lined: used for high corrosion conditions ,low pressure andnormal temperatures, such as seawater.

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5. Cast irons: used for underground utilities, sewers and process drainagesystems.

example: grey cast iron, ductile iron.

6. Non metallic: used for better corrosion resistance at low pressure andnormal temperature conditions. Limited to a maximum temperature of100°C.

example: GRP (glass reinforced plastic) – polyethylene.

7. Plastic lined: Used for chemical resistance, limited to maximum servicetemperature of 100°C.

8. Cement lined: used for high corrosion conditions ,low pressure andnormal temperatures, such as seawater.

ASTM Material Groups & Specifications

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ASTM Material Groups & Specifications, ASTM A105

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ASTM Material Groups & Specifications, ASTM A106

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Commonly used Material

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Commonly used Material

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Pipe size.

Nominal pipe size (NPS) is a dimensionless designator of pipe size. Itindicates standard pipe size when followed by the specific sizedesignation number with out an inch symbol. For example, NPS 2indicates a pipe whose outside diameter is 2.375 in. The NPS 12 andsmaller pipe has outside diameter greater than the size designator (say, 2,4, 6, . . .). However, the outside diameter of NPS 14 and larger pipe is thesame as the size designator in inches. For example, NPS 14 pipe has anoutside diameter equal to 14 in. The inside diameter will depend upon thepipe wall thickness specified by the schedule number. Refer to ASMEB36.10 .

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Nominal pipe size (NPS) is a dimensionless designator of pipe size. Itindicates standard pipe size when followed by the specific sizedesignation number with out an inch symbol. For example, NPS 2indicates a pipe whose outside diameter is 2.375 in. The NPS 12 andsmaller pipe has outside diameter greater than the size designator (say, 2,4, 6, . . .). However, the outside diameter of NPS 14 and larger pipe is thesame as the size designator in inches. For example, NPS 14 pipe has anoutside diameter equal to 14 in. The inside diameter will depend upon thepipe wall thickness specified by the schedule number. Refer to ASMEB36.10 .

ASME B36.10

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ISO Standard

Diameter nominal (DN) is also a dimensionless designator of pipe size inthe metric unit system, developed by the International StandardsOrganization (ISO).It indicates standard pipe size when followed by thespecific size designation number.

NPS DN NPS DN

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1/8 6 4 1001/2 15 6 1503/4 20 12 3001 25 24 600

1 1/2 40 40 10002 50 42 10503 80 60 1500

2- Flanges

A flange is a piping element that connects pipes, fitting or valves together.

Design codes

1. ASME/ANSI B16.5 : Steel flanges sizes ½” to 24”.

2. ASME/ANSI B 16.47: large size steel flanges 26” to 60”.

3. API 605: large size flanges 26” to 60”.

4. ASME B 16.36: Orifice flange

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A flange is a piping element that connects pipes, fitting or valves together.

Design codes

1. ASME/ANSI B16.5 : Steel flanges sizes ½” to 24”.

2. ASME/ANSI B 16.47: large size steel flanges 26” to 60”.

3. API 605: large size flanges 26” to 60”.

4. ASME B 16.36: Orifice flange

Flange types

No. Flange type Service conditions1 Welding neck For high pressure process conditions2 Socket weld For low pressure process and utilities3 Screwed For small pressure utility condition and small sizes4 Slip on For large sizes and limited pressures5 Lap joint For special corrosive conditions

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5 Lap joint For special corrosive conditions6 Blind For all pressure process and utilities7 Orifice For instrumentation reasons , all pressure sizes 2” and

larger.

Flange types

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Flange types

Orifice flange ASME B 16.36

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Flange facing

Flat face (FF)

Raised face (RF)

Ring joint (RJ)

Lap joint (LJ)

Tongue and groove (T&G)

Male and female (M&F)

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Flat face (FF)

Raised face (RF)

Ring joint (RJ)

Lap joint (LJ)

Tongue and groove (T&G)

Male and female (M&F)

Flange facing .

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Flange pressure / temperature ratings

As per ASME B16.5 / ASME B 16.47 these are combinations of pressureand temperature design conditions, combined with flanges materials.

There are seven classes of pressure/temperature rating in ASME B16.5 /ASME 16.47 they are classes 150 300 400 600 900 1500 & 2500.

For higher pressure / temperature rating, API 6A Code (well head flanges)classes 5000&10000 PSI shall be used.

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As per ASME B16.5 / ASME B 16.47 these are combinations of pressureand temperature design conditions, combined with flanges materials.

There are seven classes of pressure/temperature rating in ASME B16.5 /ASME 16.47 they are classes 150 300 400 600 900 1500 & 2500.

For higher pressure / temperature rating, API 6A Code (well head flanges)classes 5000&10000 PSI shall be used.

Temperature and pressure ratings of flangesconforming dimensions ASME B16.5 and materialsspecification ASTM A-105

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ASME B16.5 Flange Rating Chart

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API flanges, API 6A

As per API 6A , Classes of flanges as below

API 6A - Type - 6B 13.8 MPA (2000 psi) API 6A - Type - 6B 20.7 MPA (3000 psi) API 6A - Type - 6B 34.5 MPA (5000 psi) API 6A - Type - 6BX 13.8 MPA (2000 psi) API 6A - Type - 6BX 20.7 MPA (3000 psi) API 6A - Type - 6BX 34.5 MPA (5000 psi) API 6A - Type - 6BX 69.0 MPA (10000 psi) API 6A - Type - 6BX 103.5 MPA (15000 psi) API 6A - Type - 6BX 138.0 MPA (20000 psi)

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As per API 6A , Classes of flanges as below

API 6A - Type - 6B 13.8 MPA (2000 psi) API 6A - Type - 6B 20.7 MPA (3000 psi) API 6A - Type - 6B 34.5 MPA (5000 psi) API 6A - Type - 6BX 13.8 MPA (2000 psi) API 6A - Type - 6BX 20.7 MPA (3000 psi) API 6A - Type - 6BX 34.5 MPA (5000 psi) API 6A - Type - 6BX 69.0 MPA (10000 psi) API 6A - Type - 6BX 103.5 MPA (15000 psi) API 6A - Type - 6BX 138.0 MPA (20000 psi)

API Flanges

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3- Pipe fittings and branch connections

A fitting is a piping element that connects a pipe or flange in order tofacilitate the flow direction change.

A branch connection is a piping element that connects two pipes with aspecified angle i.e not the same centerline.

Steel fittings may be classified as:

1. Forged (socket weld or screwed : for small sizes.)

2. Welded for all pipe sizes.

3. Flanged for special purposes.

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A fitting is a piping element that connects a pipe or flange in order tofacilitate the flow direction change.

A branch connection is a piping element that connects two pipes with aspecified angle i.e not the same centerline.

Steel fittings may be classified as:

1. Forged (socket weld or screwed : for small sizes.)

2. Welded for all pipe sizes.

3. Flanged for special purposes.

Branch connections.

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Pipe fittings

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Pipe fittings and branch connections

Codes of design:

1. ASME/ANSI B16.9: Wrought steel butt weld fittings.

2. ASME/ANSI B 16.11: Socket weld and threaded fittings.

3. ASME/ANSI B 16.15: Cast bronze threaded fittings .

4. ASME/ANSI B 16.4: Cast iron threaded fittings .

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Codes of design:

1. ASME/ANSI B16.9: Wrought steel butt weld fittings.

2. ASME/ANSI B 16.11: Socket weld and threaded fittings.

3. ASME/ANSI B 16.15: Cast bronze threaded fittings .

4. ASME/ANSI B 16.4: Cast iron threaded fittings .

Pipe fittings and branch connections

Wall Thickness

1. Socket weld and screwed fittings specified by rating (2000#, 3000#,6000#, 9000#)

2. Butt welding fitting thickness is generally equal to pipe to which thefitting is welded as per ASME 36.10

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4- Gaskets

Gaskets are used to create a static seal between two stationary membersof a mechanical assembly and to maintain that seal under operatingconditions which may vary dependent upon changes in pressures andtemperatures.

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Gasket Types- Metallic Gaskets

Shape: Octagonal and Oval

Size: R, RX or BX number

Material: SS-304/316/321/347/410/F-5, Soft iron ‘D’, HasteloyInconel & Monel Maximum P-T rating: 150-5000 Class

Standard: ASME B16.20

Application: Flanges of ASME B 16.5, ASME B 16.47, or APISpecification 6A).

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Shape: Octagonal and Oval

Size: R, RX or BX number

Material: SS-304/316/321/347/410/F-5, Soft iron ‘D’, HasteloyInconel & Monel Maximum P-T rating: 150-5000 Class

Standard: ASME B16.20

Application: Flanges of ASME B 16.5, ASME B 16.47, or APISpecification 6A).

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Gasket Types- Semi Metallic - Spiral Wound

Application: Flanges of ASME B16.5 & B16.47Standard: ASME B16.20

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MODULE 2WELDING

1-Welding Processes

41

Shielded Metal Arc Welding

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Tungsten Arc Welding

Page 43 43

Gas Metal Arc Welding

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Submerged Arc Welding

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2-Welding symbols

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Page 48COPYRIGHT 1999 American Welding Society, Inc. Information Handling Services,September 10, 1999 06:07:26COPYRIGHT 1999 American Welding Society, Inc. Information Handling Services,September 10, 1999 06:07:26

Page 49COPYRIGHT 1999 American Welding Society, Inc. Information Handling Services,September 10, 1999 06:07:26COPYRIGHT 1999 American Welding Society, Inc. Information Handling Services,September 10, 1999 06:07:26

3-Welding electrodes identificationAWS 5.1 Electrodes, SMAW Carbon steel Electrodes

The American Welding Society (AWS) numbering system can tell a welderquite a bit about a specific stick electrode including what application itworks best in and how it should be used to maximize performance. Withthat in mind, let's take a look at the system and how it works.

The prefix "E" designates an arc welding electrode. The first two digits ofa 4-digit number indicate minimum tensile strength. For example, E6010is a 60,000 psi tensile strength electrode. E 60 1 0 Electrode Tensile Strength Position Type of Coating and Current

Page 50

The American Welding Society (AWS) numbering system can tell a welderquite a bit about a specific stick electrode including what application itworks best in and how it should be used to maximize performance. Withthat in mind, let's take a look at the system and how it works.

The prefix "E" designates an arc welding electrode. The first two digits ofa 4-digit number indicate minimum tensile strength. For example, E6010is a 60,000 psi tensile strength electrode. E 60 1 0 Electrode Tensile Strength Position Type of Coating and Current

Welding electrodes identification

The next to last digit indicates position. The "1" designates an all positionelectrode, "2" is for flat and horizontal positions only; while "4" indicatesan electrode that can be used for flat, horizontal, vertical down andoverhead. The last 2 digits taken together indicate the type of coating andthe correct polarity or current to use.

E6010DC only and designed for putting the root bead on the inside of a piece ofpipe, this is the most penetrating arc of all. It is tops to dig through rust, oil,paint or dirt. It is an all-position electrode .

E7018A low-hydrogen, usually DC, all-position electrode used when quality is anissue or for hard-to-weld metals. It has the capability of producing moreuniform weld metal, which has better impact properties at temperaturesbelow zero.

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The next to last digit indicates position. The "1" designates an all positionelectrode, "2" is for flat and horizontal positions only; while "4" indicatesan electrode that can be used for flat, horizontal, vertical down andoverhead. The last 2 digits taken together indicate the type of coating andthe correct polarity or current to use.

E6010DC only and designed for putting the root bead on the inside of a piece ofpipe, this is the most penetrating arc of all. It is tops to dig through rust, oil,paint or dirt. It is an all-position electrode .

E7018A low-hydrogen, usually DC, all-position electrode used when quality is anissue or for hard-to-weld metals. It has the capability of producing moreuniform weld metal, which has better impact properties at temperaturesbelow zero.

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Welding electrodes identification

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Welding electrodes identificationAWS 5.18 Electrodes, GTAW Carbon steel Electrodes

ER70S-3

(ER) Electrode Rod that will produce weld metal of a minimum 70,000psitensile strength (70); (S) is a solid bare wire or welding rod; of a specificchemical composition (3) .

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4-Welding procedure specifications

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5-Discontinuities.

Typical discontinuities found in welds are:

1. Porosity

2. Incomplete fusion

3. Incomplete penetration

4. Undercut

5. Overlap

6. Cracks

7. Slag inclusions

8. Excessive reinforcement

Page 57 57

While code requirements may permit limitedamounts of some of these discontinuities, cracks,and incomplete fusion defects are never allowed.

1. Porosity

2. Incomplete fusion

3. Incomplete penetration

4. Undercut

5. Overlap

6. Cracks

7. Slag inclusions

8. Excessive reinforcement

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6-Introduction to NDT.

Overview of Six Most Common NDT Methods

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The use of noninvasivetechniques to determinethe integrity of a material,component or structure

orquantitatively measuresome characteristic ofan object.

Definition of NDT

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The use of noninvasivetechniques to determinethe integrity of a material,component or structure

orquantitatively measuresome characteristic ofan object.

i.e. Inspect or measure without doing harm.

What are Some Usesof NDE Methods?

Flaw Detection and Evaluation

Leak Detection

Location Determination

Dimensional Measurements

Structure and Microstructure Characterization

Estimation of Mechanical and Physical Properties

Stress (Strain) and Dynamic Response Measurements

Material Sorting and Chemical Composition Determination

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Flaw Detection and Evaluation

Leak Detection

Location Determination

Dimensional Measurements

Structure and Microstructure Characterization

Estimation of Mechanical and Physical Properties

Stress (Strain) and Dynamic Response Measurements

Material Sorting and Chemical Composition Determination

When are NDE Methods Used?

– To assist in product development

– To screen or sort incoming materials

– To monitor, improve or control manufacturingprocesses

– To verify proper processing such as heat treating

– To verify proper assembly

– To inspect for in-service damage

There are NDE application at almost any stagein the production or life cycle of a component.There are NDE application at almost any stagein the production or life cycle of a component.

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– To assist in product development

– To screen or sort incoming materials

– To monitor, improve or control manufacturingprocesses

– To verify proper processing such as heat treating

– To verify proper assembly

– To inspect for in-service damage

Six Most Common NDT Methods

• Visual• Liquid Penetrant• Magnetic• Ultrasonic• Eddy Current• X-ray

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• Visual• Liquid Penetrant• Magnetic• Ultrasonic• Eddy Current• X-ray

• A liquid with high surface wetting characteristics isapplied to the surface of the part and allowed time toseep into surface breaking defects.

• The excess liquid is removed from the surface ofthe part.

• A developer (powder) is applied to pull thetrapped penetrant out the defect and spread it onthe surface where it can be seen.

Liquid Penetrant Inspection

Page 65

• A developer (powder) is applied to pull thetrapped penetrant out the defect and spread it onthe surface where it can be seen.

• Visual inspection is the final step in the process.The penetrant used is often loaded with afluorescent dye and the inspection is done underUV light to increase test sensitivity.

Magnetic Particle Inspection

The part is magnetized. Finely milled iron particles coated with a dyepigment are then applied to the specimen. These particles are attractedto magnetic flux leakage fields and will cluster to form an indicationdirectly over the discontinuity. This indication can be visually detectedunder proper lighting conditions.

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Radiography

The radiation used in radiography testingis a higher energy (shorter wavelength)version of the electromagnetic waves thatwesee as visible light. The radiation cancome from an X-ray generator or aradioactive source.

High Electrical Potential

Electrons-+

X-ray Generatoror Radioactive

Source CreatesRadiation

Page 67

X-ray Generatoror Radioactive

Source CreatesRadiation

Exposure Recording Device

RadiationPenetratethe Sample

Film Radiography

The part is placed between the radiationsource and a piece of film. The part willstop some of the radiation. Thicker andmore dense area will stop more of theradiation.

The film darkness(density) will vary withthe amount of radiationreaching the film throughthe test object.

Page 68 Top view of developed film

X-ray film

= more exposure

= less exposure

The film darkness(density) will vary withthe amount of radiationreaching the film throughthe test object.

Radiographic Images

Page 69

CoilCoil'smagnetic field

Eddy current's

Eddy Current Testing

Page 70

Conductivematerial

Eddycurrents

Eddy current'smagnetic field

Eddy Current Testing

Eddy current testing is particularly well suited for detecting surfacecracks but can also be used to make electrical conductivity and coatingthickness measurements. Here a small surface probe is scanned overthe part surface in an attempt to detect a crack.

Eddy current testing is particularly well suited for detecting surfacecracks but can also be used to make electrical conductivity and coatingthickness measurements. Here a small surface probe is scanned overthe part surface in an attempt to detect a crack.

Page 71

High frequency sound waves are introduced into a materialand they are reflected back from surfaces or flaws.

Reflected sound energy is displayed versus time, andinspector can visualize a cross section of the specimenshowing the depth of features that reflect sound. f

Ultrasonic Inspection (Pulse-Echo)

Page 72

platecrack

0 2 4 6 8 10

initialpulse

crackecho

back surfaceecho

Oscilloscope, orflaw detectorscreen

Module 3Hot Tapping Requirements

1- Definition

Hot Tapping is the precise process of drilling a hole in an on- stream pipingsystem without spilling its contents or interrupting its flow.

or in a practical sense

Hot Tapping is a means by which access is made to the inside of anoperational pipeline, using either a drill or a circular cutter. Applicationsinclude attachment of a branch connection to the line, installation of aninternal probe or monitor, and to stop or redirect flow in a line formaintenance or repair purposes.

Implies positioning a branch fitting on an operating pressurized line,flowing or stagnant. Then cutting a hole in the run through the branch toallow connection to the flowing media. Normally implies using a weldedfitting.

Page 74

Hot Tapping is the precise process of drilling a hole in an on- stream pipingsystem without spilling its contents or interrupting its flow.

or in a practical sense

Hot Tapping is a means by which access is made to the inside of anoperational pipeline, using either a drill or a circular cutter. Applicationsinclude attachment of a branch connection to the line, installation of aninternal probe or monitor, and to stop or redirect flow in a line formaintenance or repair purposes.

Implies positioning a branch fitting on an operating pressurized line,flowing or stagnant. Then cutting a hole in the run through the branch toallow connection to the flowing media. Normally implies using a weldedfitting.

Typical Hot Tapping Procedure

Page 75

(Shown: Standard Valve usedwhen tapping to install laterallines.SANDWICH® ValveOption allows temporaryplugging operation.)

1.A fitting is permanentlysecured to the line.2. A permanent valve isinstalled on the fitting.

3.A Tapping Machine is installed onthe fitting, and the valve is opened. Afterpilot drill penetrates, the tapping machinefills with product, and air is purgedfrom the housing. The tap is makethrough the line and the coupon isretained.

4.The valve is closed, andthe tapping machine isremoved. A branchconnection is added, and thevalve is opened. The newconnection is ready to putinto service. This field-proven Procedure is quickand precise.

Coupon is removed by Tapping Cutter

Coupon is Retained by Pilot Drill U-Rods

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2- Purpose of Hot Tapping.

Hot tapping is usually performed when it is not feasible, or is impractical,to take the equipment or piping out of service, or to purge or clean it byconventional methods. With proper review to determine that a hot tap isappropriate, and development and conformance to job specificprocedures, many hot tap connections have been safely made withoutinterfering with the process operation.

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3-Parameters that affect Hot Tapping.3.1Internal pipeline condition

3.1.1Content :

Welding and hot tapping should not be performed on piping or equipmentcontaining the following materials:

a. Vapor/air or vapor/oxygen mixtures near or within their flammableexplosive range.

b. Oxygen or oxygen enriched atmosphere.

c. Compressed air systems, unless known to be free of flammables andcombustibles

d. Hydrogen

e. Temperature-sensitive, chemically reactive materials

f. Caustics, amines, and acids (such as HF acid)

g. Certain unsaturated hydrocarbons (such as ethylene)

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3.1Internal pipeline condition

3.1.1Content :

Welding and hot tapping should not be performed on piping or equipmentcontaining the following materials:

a. Vapor/air or vapor/oxygen mixtures near or within their flammableexplosive range.

b. Oxygen or oxygen enriched atmosphere.

c. Compressed air systems, unless known to be free of flammables andcombustibles

d. Hydrogen

e. Temperature-sensitive, chemically reactive materials

f. Caustics, amines, and acids (such as HF acid)

g. Certain unsaturated hydrocarbons (such as ethylene)

3-Parameters that affect Hot Tapping.3.1.2 Flow in lines

Higher flow increases the weld cooling rate and the risk of cracking.Therefore, when welding, it is desirable to provide some minimum level offlow while avoiding high flow rates. The need for a minimum level of flowis a trade-off between the need to minimize the risks of burn-through andcracking.

For metal thickness between 1/4 in. (6.4 mm) and 1/2 in.(12.7 mm), flowalso increases the weld cooling rate and risk of cracking. Minimizing theflow rate reduces the risk of cracking and keeps the risk of burn throughlow. For metal thickness greater than 1/2 in. (12.7 mm), the effect of flowon both weld cooling rates and the risk of burn-through may be negligible.

Recommended flow rate during welding 0.4<X<1.2 m/s in case of liquid. 0.4< X< NOLIMIT in case of Gas.

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3.1.2 Flow in lines

Higher flow increases the weld cooling rate and the risk of cracking.Therefore, when welding, it is desirable to provide some minimum level offlow while avoiding high flow rates. The need for a minimum level of flowis a trade-off between the need to minimize the risks of burn-through andcracking.

For metal thickness between 1/4 in. (6.4 mm) and 1/2 in.(12.7 mm), flowalso increases the weld cooling rate and risk of cracking. Minimizing theflow rate reduces the risk of cracking and keeps the risk of burn throughlow. For metal thickness greater than 1/2 in. (12.7 mm), the effect of flowon both weld cooling rates and the risk of burn-through may be negligible.

Recommended flow rate during welding 0.4<X<1.2 m/s in case of liquid. 0.4< X< NOLIMIT in case of Gas.

3-Parameters that affect Hot Tapping.

3.1.3 Pipe Line content pressure & Temperature

The pipeline content pressure and temperature should not exceed theallowable pressure / temperature rating of the used hot tapping machine.

the leak test pressure for tapping machine and fitting should not exceed 1.1of the pipeline operating pressure during tapping operation.

3.2 Pipeline Specification3.2.1 pipeline material and grade.

Pipeline material and grade should be identified in order to select :

1. Suitable pilot drill and cutter material.

2. Suitable welding procedure specification.

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3.1.3 Pipe Line content pressure & Temperature

The pipeline content pressure and temperature should not exceed theallowable pressure / temperature rating of the used hot tapping machine.

the leak test pressure for tapping machine and fitting should not exceed 1.1of the pipeline operating pressure during tapping operation.

3.2 Pipeline Specification3.2.1 pipeline material and grade.

Pipeline material and grade should be identified in order to select :

1. Suitable pilot drill and cutter material.

2. Suitable welding procedure specification.

3-Parameters that affect Hot Tapping.

3.2.2 pipeline metal thickness and outer diameter The piping or equipment base metal thickness must provide support for

the new connection and the hot tapping machine. Alternately, reinforcingpads or auxiliary support of the hot tapping machine may be provided.

A minimum base metal thickness of 3/16 in. (4.8 mm) is recommended formost applications of welding and hot tapping. The actual minimumthickness is a function of the thickness required for strength, plus a safetyfactor, usually 3/32 in. (2.4 mm), to prevent burn through.

Pipeline outer diameter , wall thickness and the required branchconnection diameter are determined the selection of branch connectiontype (weldolet , split tee , --), and also determined the type of cutter to beused in case of flat plate condition.

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3.2.2 pipeline metal thickness and outer diameter The piping or equipment base metal thickness must provide support for

the new connection and the hot tapping machine. Alternately, reinforcingpads or auxiliary support of the hot tapping machine may be provided.

A minimum base metal thickness of 3/16 in. (4.8 mm) is recommended formost applications of welding and hot tapping. The actual minimumthickness is a function of the thickness required for strength, plus a safetyfactor, usually 3/32 in. (2.4 mm), to prevent burn through.

Pipeline outer diameter , wall thickness and the required branchconnection diameter are determined the selection of branch connectiontype (weldolet , split tee , --), and also determined the type of cutter to beused in case of flat plate condition.

3-Parameters that affect Hot Tapping.

3.3 branch connection3.3.1 branch connection size & internal diameterIt Should be specified as it affect cutter size and tapping machine

selection.3.3.2 branch connection lengthBranch connection length (top of flange – top of pipe) should be

measured .

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3.3 branch connection3.3.1 branch connection size & internal diameterIt Should be specified as it affect cutter size and tapping machine

selection.3.3.2 branch connection lengthBranch connection length (top of flange – top of pipe) should be

measured .

3-Parameters that affect Hot Tapping

3.4 valves The hot tap valve to be used must be of adequate size and rating, be of

proper metallurgy, and be a full opening valve.

The hot tap valve should be tested for seat leakage prior to installation(see API Std 598).

During installation the valve should be centered on the nozzle flange orfixture.

Run the boring bar through the valve opening to be sure the cutter doesnot jam or drag.

Valve face to face dimensions must be determined.

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3.4 valves The hot tap valve to be used must be of adequate size and rating, be of

proper metallurgy, and be a full opening valve.

The hot tap valve should be tested for seat leakage prior to installation(see API Std 598).

During installation the valve should be centered on the nozzle flange orfixture.

Run the boring bar through the valve opening to be sure the cutter doesnot jam or drag.

Valve face to face dimensions must be determined.

Hot Tapping Application Data Sheet

Page 84

4- Hot Tapping Check List

Page 85

4- Hot Tapping Check List

Page 86

4- Hot Tapping Check List

Page 87

Hot Tapping SimulationSimulate tapping machine in workshop

Tapping machine cutter & pilot drill

Page 89

Standard cutter & tank cutter

Page 90

Machine installation

Page 91

Coupon

Page 92

References ASME B 16.5

ASME B 16.47

ASME B 36.10

AWS A 5.1

AWS A 2.4

AWS A 5.18

API 6A

API RP 2201

TDW hot tapping procedure and application by William Jarvis

Piping fundamentals by Mohinder L Nayyar, Bechtel Power Corporation

Page 93

ASME B 16.5

ASME B 16.47

ASME B 36.10

AWS A 5.1

AWS A 2.4

AWS A 5.18

API 6A

API RP 2201

TDW hot tapping procedure and application by William Jarvis

Piping fundamentals by Mohinder L Nayyar, Bechtel Power Corporation

Prepared by Eng.Wael ElarinyTHANK YOU

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