backwash automation at nyngan wtp · details of weld preparations including reference to...

ADDENDUM 1 PIPEWORK REQUIREMENTS

BACKWASH AUTOMATION AT NYNGAN WTP CONTRACT NO: 2019/1/BACKWASH AUTOMATION

Engineering Department 27 May 2019

Bogan Shire Council A.B.N. 95 717 801 565 Addendum – Pipework requirements

Backwash Automation at Nyngan WTP 2019/1/BACKWASH AUTOMATION

[blank]



CONTENTS

1 ADDENDUM 1 .................................................................................................................................... 1

2 FILTER INLET VALVE LOCATION .................................................................................................... 1

3 LIMITS ................................................................................................................................................ 2

4 OUTLET MANIFOLD .......................................................................................................................... 3

5 CHANGEOVER RESTRICTIONS ....................................................................................................... 3

6 PIPEWORK TECHNICAL REQUIREMENTS ..................................................................................... 3

7 METALWORK..................................................................................................................................... 3

7.1 General .............................................................................................................................. 3

7.2 Materials, Steel and Aluminium ......................................................................................... 3

7.2.1 Steel .................................................................................................................................. 3

7.2.2 Aluminium.......................................................................................................................... 4

7.3 Quality of Finish ................................................................................................................. 4

7.4 Welding ............................................................................................................................. 4

7.5 Qualification Procedures and Personnel ........................................................................... 5

7.5.1 General .............................................................................................................................. 5

7.5.2 Destructive Testing............................................................................................................ 5

7.5.3 Qualification of Welding Personnel ................................................................................... 5

7.6 Non-Destructive Testing .................................................................................................... 5

7.6.1 General .............................................................................................................................. 5

7.6.2 Welding Inspection ............................................................................................................ 5

7.6.3 Radiographic Examination - General ................................................................................ 6

7.7 Bolts, Nuts, Washers and Jointing Material ...................................................................... 6

7.7.1 General .............................................................................................................................. 6

7.7.2 Bolts in Bearing ................................................................................................................. 7

7.7.3 Connection Bolts ............................................................................................................... 7

7.7.4 Foundation Bolts ............................................................................................................... 7

7.7.5 Fixing to Concrete ............................................................................................................. 7

7.7.6 Lock Nuts .......................................................................................................................... 7

7.8 Bedding and Grouting ....................................................................................................... 7

7.9 Transport Storage and Erection ........................................................................................ 7

7.9.1 Temporary connections ..................................................................................................... 8

7.9.2 Anchor bolts ...................................................................................................................... 8

7.9.3 Masonry anchors ............................................................................................................... 8

7.10 Finishes ............................................................................................................................. 8

7.10.1 Surface Preparation .......................................................................................................... 8



7.10.2 Marking ............................................................................................................................. 9

7.10.3 Field Connections ............................................................................................................. 9

7.10.4 Abrasive Blast Cleaning .................................................................................................... 9

7.11 Built-In Metalwork ............................................................................................................. 9

7.12 Corrosion Protection of Metalwork ................................................................................... 9

7.12.1 General ............................................................................................................................. 9

7.12.2 Hot Dip Galvanising .......................................................................................................... 9

7.12.3 Galvanic Corrosion ......................................................................................................... 10

8 PIPEWORK ...................................................................................................................................... 10

8.1 Materials and Other Requirements ................................................................................. 10

8.2 Stainless Steel Pipe and Fittings .................................................................................... 11

8.3 Passivation of Stainless Steel ......................................................................................... 11

8.4 PVC-O Pressure Pipe and Fittings ................................................................................. 12

8.5 PVC Non Pressure Pipe and Fittings .............................................................................. 12

8.6 PVC Flexible Pipe and Fittings ....................................................................................... 13

8.7 Expansion Joints ............................................................................................................. 13

8.8 Metal Banded Flexible Couplings ................................................................................... 13

8.9 Pipe Installation and Jointing .......................................................................................... 13

8.9.1 Pressure Main Thrust and Anchor Blocks ...................................................................... 13

8.9.2 Flanged Joints ................................................................................................................ 13

8.9.3 Dismantling / Expansion Joints ....................................................................................... 14

8.9.4 Connections for Pipework and Fittings ........................................................................... 14

8.10 Construction of Piping through Walls ............................................................................. 14

8.11 Initial Testing of Gravity Pipelines Only .......................................................................... 14

8.12 Air Testing ....................................................................................................................... 15

8.13 Hydrostatic Testing ......................................................................................................... 16

8.14 Acceptance Testing of Gravity Pipelines ........................................................................ 16

8.15 Hydrostatic Acceptance Testing of Watermains, Sewer / Sludge Rising Mains ............. 16

9 DISINFECTION ................................................................................................................................ 17

9.1 General ........................................................................................................................... 17

9.2 Flushing of Disinfection Water ........................................................................................ 17

9.3 Bacteriological Test ........................................................................................................ 18

10 STAINLESS STEEL PIPEWORK HOLD POINTS ........................................................................... 18



[blank]



1

1 ADDENDUM 1

The following provides further detail regarding General Specification Cl. ‘A10.10 Replacement Pipework’

The attached drawings provide detail of the installed pipework and are provided for information only.

It is not anticipated that the pipework is replaced ‘like for like’ but instead should be a new and revised design.

2 FILTER INLET VALVE LOCATION

The scope of works requests five (5) new Inlet valves and sought a solution for access. To facilitate access to these actuators, it is now requested that these are installed on the outside of the building, between the existing flanges (as can be seen in the below photograph). This will require the existing manifold to be moved outward and provision of replacement supports. Due to the uncertainty around the condition of the wall. The new arrangement shall be supported from the ground.

In addition, this will involve the installation of cable ladder (~30metres) and additional cable to reach the actuators for control and monitoring.

Figure 1 - Inlet Manifold


2 Backwash Automation at Nyngan WTP 2019/1/BACKWASH AUTOMATION

Figure 2 - Proposed Inlet Valve Location

3 LIMITS

The extent of pipe replacement is limited to the pipework within the building and does not include the pump delivery manifolds.

Note that the backwash pipe is actually the start of the treated water reticulation network. The treated water pumps draw from the on-site storage to push through this pipe to the town retic and stand-pipe storages. Backwashing occurs via gravity pushing back through the retic pipe. The below sketch is an extract taken from the top of drawing 82008-2.



3

4 OUTLET MANIFOLD

BSC wish to replace the existing arrangement, where filtered water flows through an open channel. The proposed new arrangement is for provision of a fully enclosed common filtered water manifold. This would require full Contractor design of sizing, hydraulic grading, supports and installation methodology.

5 CHANGEOVER RESTRICTIONS

During the changeover period, the WTP must be capable of producing water on a daily basis for a minimum of 6 hours at full capacity (during Winter period). Therefore, the Contractor must work closely with the BSC operations staff to develop a detailed cutover plan and stage the works to allow hand-back of (a large part) of the WTP to BSC Operations staff daily. During the Summer period the duration required to produce water extends to 10 hours.

6 PIPEWORK TECHNICAL REQUIREMENTS

The following Clauses shall apply to the design, supply and installation of the pipework and associated works:

7 METALWORK

7.1 General Metalwork includes covers, handrails, gratings, metal plates, anchor bolts, covers, uni-struts, and such other miscellaneous embedded and non-embedded metalwork as determined necessary during the design process.

Second hand and recycled materials shall not be used in fabrication, all materials shall be first quality to the required standards and requirements of the Contract. The joining of short sections shall not be carried out where stock lengths/sheets would permit fabrication without joints/welds.

The design, construction and workmanship of metalwork to comply with the requirements of the all relevant Australian Standards and not overridden by this Specification.

7.2 Materials, Steel and Aluminium Provide isolation between dissimilar metals. Materials are to be as nominated in the drawings forming part of the Design Documents. When not specified materials are to meet the following minimum standards.

7.2.1 Steel Where steel is employed it is to generally comply, unless noted otherwise, with the following:

(a) stainless steel to ASTM A240/A240M and AS2837, grade 316;

(b) all stainless steel bolts, nuts and washers are to be grade 316;

(c) passivate all stainless steel after fabrication prior to installation;structural grade 300 (min) steel to AS3678 and AS3679. Fabricate in accordance with AS4100. Round all cut edges to 3mm radius;



(d) structural steel is to be fabricated and erected in a manner that is safe using methods complying with the requirements of AS3990 for materials, construction, fabrication and erection; and

(e) galvanised steel may only be used on items (e.g. light stands) that can be easily replaced without any interruption to the treatment process or other critical functions. Galvanised steel may also be used for all building / enclosure structural members.

7.2.2 Aluminium Where aluminium is employed it is to generally comply, unless noted otherwise, with the following:

(a) use shapes and appurtenant materials from aluminium alloys known commercially as 5251-H34, 5251-H32, 6106-T5, 6106-T6, 6061-T6 and 6063-T5;

(b) fabricate in accordance with AS1664 and AS1665; and

(c) bolt all aluminium members with grade 316 stainless steel bolts.

7.3 Quality of Finish Neatly machine, saw or flame cut all edges of plates and members. Grind smooth all sharp, sheared and flame cut edges to a minimum curvature of 3mm.

Fair-face sharp corners and edges marred, cut or roughened in handling or erection by grinding or other approved means.

Do not heat stainless steel for purposes of bending, shaping or straightening.

Completed members shall be free from twists, bends and open joints. Sharp kinks or bends shall be cause for rejection.

Verify all dimensions and be responsible for their accuracy.

Give particular attention to finish of metalwork where exposed to view. Grind smooth welds of metalwork exposed to view.

7.4 Welding

Structural steel to be “Category SP” welds in accordance with AS1554. Aluminium to be “Category B” welds in accordance with AS1665.

Before commencing fabrication submit details of proposed welding procedures, using the form in Appendix C of AS/NZS 1554.1 and/or Appendix D of AS/NZS 1665 as appropriate.

Do not commence fabrication until welding procedures have been approved by the Superintendent.

All butt welds are to be full penetration and ground flush, and all fillet welds are to be continuous.

Electrodes are to be classification E48XX to AS1554.1.

Do not weld on Site without prior approval from the Superintendent. Wherever possible locate Site welds in positions for down hand welding.

Use supervisors and welders who have suitable training and practical experience in the execution of this grade of work.



5

Completed work is to be free from distortions and true to dimensions. Make due allowance for dimensional changes during welding.

All welds are to show a good even contour, a good penetration and fusion with the parent metal, and be without cracks, undercuts, overlaps, excessive slag inclusions and excessive porosity. Cut out unacceptable welds and re-weld.

Testing and repair is to be performed in accordance with suggested requirements of AS1554 and AS1665. Test results are to be supplied to the Superintendent within 14 Business Days’ of testing.

7.5 Qualification Procedures and Personnel

7.5.1 General All welding procedures and all welders are to be qualified prior to commencement of welding in accordance with AS1554.

Submit details of the proposed weld together with evidence of qualification (in accordance with AS1554) to the Superintendent for review.

Details of weld preparations including reference to pre-qualified preparation numbers are to be submitted on the shop drawings.

7.5.2 Destructive Testing If qualification by impact testing is required (in accordance with AS1554), then the minimum required “Charpy-V” impact properties are to be in accordance with table 4.5.2 of AS1554.

7.5.3 Qualification of Welding Personnel All welders are to be approved before welding. A welder who has successfully qualified for the specific weld procedures to be used is to be considered to have been approved for those procedures only. Qualifications are to be in accordance with AS1554. Submit records to the Superintendent of each welder's approvals prior to commencement of Site fabrication work.

7.6 Non-Destructive Testing

7.6.1 General All non-destructive testing is to be carried out in accordance with AS1554 and AS2177.1 unless noted otherwise. The extent of non-destructive testing is to be as agreed between the weld inspector referred to within Specification and the Superintendent.

7.6.2 Welding Inspection The Superintendent is to approve the independent weld inspector to be employed by the Contractor to carry out welding inspection of all welds carried out on Site. The amount of testing to be carried out is to be by agreement between the weld inspector and the Superintendent.

The location of testing is also be established by agreement between the weld inspector and the Superintendent. All weld test reports are to be submitted to the Superintendent prior to acceptance.



7.6.3 Radiographic Examination - General Radiographic examination of an approved number of critical locations or areas where defects are suspected to be present are to be carried out as directed. The extent and location of radiographic examination is to be agreed between the weld inspector and the Superintendent. The following table is to be used as a basis for determining the location and extent of radiographic examination:

Location / situation Extent of radiographic examination Wherever defects are suspected and the weld inspector recommends further testing.

As directed and agreed to between the weld inspector and the Superintendent.

The examination of all welds is to be undertaken by the weld inspector and certification supplied to the Superintendent.

7.7 Bolts, Nuts, Washers and Jointing Material

7.7.1 General Supply all nuts, bolts and washers in accordance with AS2528 and AS4291. All exposed boltheads and nuts to be hexagonal and the length of all bolts is to be such that tightened bolted connections is to have a minimum of 2.5 threads and a maximum of 5 threads protruding past the nut after the joint has been tightened.

Where nuts, bolts and washers are to be employed in a submerged, splash zone or atmospheric application they are to, unless noted otherwise, be grade 316 stainless steel. All stainless steel fasteners (hexagonal nuts, bolts and screws greater than M5) are to be marked and identified according to the “ISO 3506” designation. Fasteners without markings are to be dismissed as unsuitable.

All anchors, bolts, nuts and washers to be of Grade 316 stainless steel to AS 2837. Passivate all stainless steel components. Wrapped galvanised or black steel bolting assemblies are not permitted unless approved by the Superintendent for structural reasons.

Where high strength bolting is required the materials to be employed are to be approved by the Superintendent. All high strength steel nuts, bolts and washers are to be property class 8.8 hot dipped galvanised in accordance with AS 1214 UNO or A4-80 grade 316 stainless steel.

All fasteners are to have rolled threads and all exposed boltheads and nuts are to be hexagonal. Machined threads are not acceptable. Bolt lengths are to be such that when fitted with a nut and tightened down, the threaded portion is to fill the nut and protrude from the face thereof by not more than half of the bolt diameter.

Use washers under all nuts. Use washers under bolt heads for connection to items with protective coatings. Where dissimilar metals would otherwise be in contact, use high strength fibre or phenolic insulating washers and sleeves.

Apply Loctite nickel anti-seize thread lubricant to the threads of all stainless steel nuts and bolts prior to assembly.

Lock in position all vertical bolts and nuts or bolts subject to severe vibration.

Threads of all bolts and nuts are to be smeared with nickel anti galling/anti-seize grease before assembly. Do not hand flame cut bolt holes without prior approval from the Superintendent.

In order to reduce the likelihood of galling stainless steel fasteners are to be fastened using a torque wrench to the correct tightness. Refer to The Nickel Institute publication: “Stainless Steel Fasteners – A systematic approach to their selection” for details.



7

All anchors, bolts, nuts and washers either embedded in concrete and/or used in the fabrication and/or installation of stainless steel items are to be of grade 316 stainless steel in accordance with AS 2837. Passivate all stainless steel components.

7.7.2 Bolts in Bearing No threaded portion of the bolts in bearing is to be within the thickness of the parts being jointed.

7.7.3 Connection Bolts Connections bolts to be minimum M20 hot-dipped galvanised high strength bolts, nuts and washers to AS1252 and property class 8.8, unless noted otherwise. All splash zone and/or submerged connection bolts are to be minimum M20 Grade 316 stainless steel property class 80.

7.7.4 Foundation Bolts Supply each foundation bolt with two nuts and 2 oversize washers. Provide sufficient thread to permit the levelling nut to be set below the base plate.

Foundation bolts are to be Grade 316 stainless steel property class 80, unless noted otherwise.

7.7.5 Fixing to Concrete The condition of the existing masonry and concrete is unknown, therefore all pipewrok shall be supported from the ground.

Where fixing to a concrete structure is required and approved to proceed by BSC, fixing is to be achieved using grade 316 stainless steel (property class 70 or greater) chemical anchors. Mechanical style anchors are not to be used.

Minimum embedment, spacing and edge distance to achieve maximum capacity is to be provided in accordance with the manufacturers recommendations unless noted otherwise on drawings.

7.7.6 Lock Nuts Provide lock nuts for bolts in moving parts or parts subject to vibration and for vertical bolts in tension. Locks nuts are to be nylon insert lock nuts (i.e. nylock nuts).

7.8 Bedding and Grouting Set up metalwork, which is supported on concrete, masonry or like material, on packing or wedges to facilitate alignment and permit subsequent grouting. Use either non-metallic or cement mortar blocks of similar strength to the permanent grout for permanent packing. Remove all other packing before completion of grouting. All grouting to comply with AS 4100.

All surfaces to receive grouting shall be mechanically scabbled and prepared and cured in strict accordance with the grout manufacturer's specific requirements, including pre-moisture conditioned and cured for the recommended moisture content and duration.

Fill any spaces with non-shrink grout or a hard setting butyl mastic (not in strip form). Repair or replace any mortar shrinkage.

7.9 Transport Storage and Erection Load, transport and unload structural members without causing excessive stress, deformity or damage. Consult with the metal work supplier to plan the loading, securing, transporting and unloading of



members is performed in accordance with WorkCover regulations and the Contractor's Safety Management Plan.

Lashing or lifting chains may cause damage to the protective coatings and finished metal work surfaces during transport and handling. It is the Contractor's responsibly to protect finished surfaces and materials through appropriate material selection for lifting and securing of loads. Similarly, consideration should be given to protection of finished surfaces likely to receive contamination or damage from fork tynes.

The use of timber gluts that are likely to stain/discolour finished surfaces shall not be used on or to support finished surfaces.

Carefully place, support and store all materials and structural members off the ground.

Handle members carefully during erection so that the members are not damaged or distorted. All connections shall be rigid and tight and the whole construction is to be in strict conformity with the Specification.

Securely fasten and temporarily brace all structures to keep stable during erection. Temporary bracing shall be sufficient to withstand heavy winds, storms and construction loads.

Provide for the thermal movements during erection.

7.9.1 Temporary connections Cleats are not to be attached without prior approval except as shown on shop drawings. Remove temporary connections upon completion and restore the surface.

Temporary connections are to be by bolted connection with bolt holes established before galvanizing or other surface protection. There is to be no drilling or welding on Site to establish temporary connections.

7.9.2 Anchor bolts For each group of anchor bolts provide a template with setting out lines clearly marked for positioning the bolts when casting in.

7.9.3 Masonry anchors If masonry anchors are required or proposed for the support or fixing of structural steel submit evidence of the anchor capacity to carry the required load.

7.10 Finishes

7.10.1 Surface Preparation All metal surfaces are to be prepared prior to erection in accordance with AS 1627.

Loose millscale, loose rust, oil, grease, dirt, globules or weld metal, weld slag and other foreign matter is to be removed from all steel surfaces prior to erection (including surfaces not otherwise treated).



9

7.10.2 Marking On the contact surfaces of friction type joints, confine the use of marking ink to the minimum necessary for making hole positions.

7.10.3 Field Connections After completing field connections, prepare the surface of the connection, adjacent unprimed surfaces and surfaces damaged during erection.

7.10.4 Abrasive Blast Cleaning Do not use silica abrasive for dry blasting and use phosphate inhibitors when wet blasting. Abrasive is to be used once only. Do not reclaim blast media. New, unused abrasive media is to be utilised.

7.11 Built-In Metalwork All built in or cast-in metalwork is to be 316 stainless steel except where high strength connection is demonstrated by the designer such as portal frame column connection.

Ensure that all built in metalwork is elevated on plinths and/ or with grout allowance above general floor area to eliminate potential of water congregation at interface of built in metalwork and floor slab.

Thoroughly clean all metalwork surfaces to be embedded in concrete or masonry of all dirt, rust, mortar and other foreign matter.

Firmly hold in the correct position all metalwork to be built into concrete while the concrete is placed.

Where metalwork is to be grouted into cored holes or blockouts, thoroughly clean the surfaces of cored holes or blockouts and coat surfaces of cored holes or blockouts and metalwork with a bonding compound compatible with the grout.

7.12 Corrosion Protection of Metalwork

7.12.1 General Protect structural mild steel in wet or splash zones by use of high solids epoxy coating system.

All other structural mild steel is to be protected by hot-dip galvanising.

7.12.2 Hot Dip Galvanising Hot-dip galvanise fabricated mild steel components after fabrication to AS 4680 and AS 1214. Galvanising coating thickness shall be not less than the values given in Table 1 of AS4680.

Prior to galvanising, clean the surfaces of all dirt, weld spatter, grease, slag, oil, paint or other deleterious matter. Chemically descale the steel surfaces in accordance with AS 1627.5 or abrasive blast clean to AS 1627.4 to Class 3 standard.

The zinc coating shall consist of a uniform layer of commercially pure zinc free of abrasions, cracks, chemical spots or other imperfections. The zinc coating shall adhere firmly to the surfaces of the steel.

Comply with the requirements of AS 4680 for quality and thickness of galvanising. If quality or thickness is found not to meet requirements of the Contract, make good the quality and thickness. Submit all



quality records to the Superintendent.

Exhaust holes are to be drilled. Flame blown holes are not allowed.

Rectify and repair defective/damaged coatings where the average zinc coating thickness is less than the minimum as specified in the Contract. For the purpose of this paragraph "average zinc coating thickness" shall be the average of not less than 10 determinations over a test area of 1 m2.

Where non-structural hot dipped galvanised metalwork and/or its zinc coating is damaged (e.g. during transport, handling, assembly, welding, etc.), repair the damaged surface by application of a zinc rich epoxy primer or an organic zinc rich paint. The use of cold gal is not permitted.

Where structural hot dipped galvanised metalwork and/or its zinc coating has been damaged or in the opinion of the Superintendent may prevent the component achieving its intended design life the damaged section of metalwork is to be repaired and re-galvanised in accordance with the requirements of AS 1214 and AS 1627.5 and AS 4680. Alternatively, replace the metalwork.

7.12.3 Galvanic Corrosion Where different metals are in contact, provide high strength phenolic insulation, including sleeves, between the metals.

8 PIPEWORK

The work under the Contract includes the design, supply, fabrication, installation and testing of pipework and supports.

Construction of all potable watermains and associated components are to comply to the requirements of the Specification and WSA 03-2011.

8.1 Materials and Other Requirements Obtain all materials necessary for construction of the Works from sources which have been approved by the Superintendent. Comply with all recommendations of the manufacturers regarding the storage and handling of the materials. Undertake all handling, transport and storage such that no damage occurs to the materials including coatings and linings.

The Superintendent may direct that any damaged material is quarantined and removed from the Site at the earliest opportunity.

Small diameter potable plumbing lines up to 50mm diameter shall be copper or polyethylene. Sufficient fixings shall be provided to ensure air lines are fully supported to prevent sagging.

Provide an inspection chamber/manhole at both changes in direction or alignment in gravity mains.

Pipework shall have the final finish colour to AS2700. The Contractor shall nominate a colour schedule for review by the Superintendent.



11

8.2 Stainless Steel Pipe and Fittings

Stainless steel pipe, tube, butt weld fittings and flanges to be grade 316L.

Pipe and tube in accordance with AS 1769 or ASTM A312M.

Fabrication and quality certification to the requirements of AS 4041 and AS/NZS 1554.6.

Fabricators to be ASSDA accredited or equivalent. Evidence supporting knowledge, experience and competence must be supplied where it is proposed to use a non-ASSDA fabricator

Welding shall be in accordance with AS 4041 and AS/NZS 1554.6 with welding undertaken by a welder certified in accordance with the requirements of AS/NZS 3992. Weld inspection and examination to be 100% visual, plus 10% ultrasonic or radiographic to the requirements of AS 4037.

Personnel responsible for inspection to be accredited by the Welding Technology Institute of Australia or meet the requirements of AS 1554.6 and/or AS 4041.

Finishing and passivation to be in accordance with the requirements of the Australian Welding Research Association (AWRA) Technical note 16 – ‘Welding of Stainless Steel”

Inspection and test plans to comply with AS/NZS 3905.2

Avoid both contact with other metals and rubbing with any other item during transportation. Do not use adhesive labels.

8.3 Passivation of Stainless Steel All stainless steel fabrications are to be passivated after all welding has been completed. Passivating preferably is to be carried out in the fabricator's workshop and may be subject to inspection by the Principal’s Authorised Person. Finishing and passivation is to be in accordance with the requirements of the AWRA Technical Note 16 – “Welding of Stainless Steel”.

Small items such as nuts, bolts, washers, screws are to be passivated by leaving them immersed overnight in a plastic bucket containing 15%-20% by volume of nitric acid in water. The items are to be thoroughly rinsed in fresh water before use.

Larger items are to be passivated by coating with a proprietary acid paste such as Sandvik "Betapaste" or equivalent. The articles are to be coated then rinsed thoroughly in water. As this product is highly corrosive and gives off fumes, it is to be used in a well ventilated area and personnel are to use rubber gloves. The manufacturer's safety precautions are to be carefully complied with.

After passivation, fabricated components are to have a clean, matt finish free from scale and discolouration caused by welding or heating.

Where passivation on the Site is unavoidable it is to be carried out in accordance with the Manufacturer's instructions and any relevant safety and regulatory regulations. No waste is to be flushed down plant pipes etc., unless neutralised satisfactorily.

Care is to be taken when handling the stainless steel before, during and after fabrication to prevent contamination with mild steel materials, dust, shavings and the like. Such care is particularly important after passivation and during transport to Site, storage and installation as these small particles rust quickly and discolour the surface of the stainless steel. This can destroy the protective oxide film and render it liable to pitting corrosion. Inspect all pipework and fittings delivered to Site to ensure no evidence of corrosion.

All stainless steel is to be passivated after installation regardless of the visual condition.



Remove sticky labels from all surfaces as soon as possible. Ensure all glue is removed from the surface.

Particular practices which shall not be undertaken are:

(a) cleaning with steel wool, wire brushes, emery paper or scraping with steel tools;

(b) use of scourers that have been used on ordinary steel;

(c) cleaning with abrasive compounds containing chlorides;

(d) blast cleaning;

(e) using muriatic (i.e. hydrochloric) acid as used in solder fluxes as it contains iron; and

(f) sieving carbon steel items in contact with stainless steel, particularly if wet.

8.4 PVC-O Pressure Pipe and Fittings Where this material is employed it is to comply, unless noted otherwise, with the following requirements:

(a) Polyvinylchloride (PVC-O) pressure pipe to comply with AS4441, Series 2.

(b) Ductile iron fittings for use with PVC pressure pipe are to comply with AS2280. Fittings to be coated and lined with fusion bonded polymer in accordance with AS4158.

(c) Ductile iron fittings to also have product certification (ISO Type 5) to AS2280. Fittings to be coated and lined with fusion bonded polymer in accordance with AS4158.

(d) Use of moulded PVC fittings is not permitted.

(e) Elastomeric joint seals are to comply with AS1646, EPDM or NR and have product certification (ISO Type 5) to AS1646.

(f) Materials in contact with drinking water to comply with AS4020.

(g) Pipe bends to have product certification (ISO Type 5) to AS4441. Products are to be marked in accordance with the certification body’s requirements.

(h) All products are to be marked in accordance with the certification body’s requirements.

(i) The supplier of products is to declare that products comply with the requirements specified.

(j) The supplier of products shall certify (in favour of the Principal and in a form approved by the Superintendent or otherwise required by the Contract) that products comply with the requirements specified in the Contract.

8.5 PVC Non Pressure Pipe and Fittings Where this material is employed it is to comply, unless noted otherwise, with the following requirements:

(a) PVC-U non-pressure pipe and fittings are to have product certification (ISO Type 5) in accordance with AS/NZS 1260. Pipe Stiffness Class SN8 (DN 150 and above) or SN10 (DN 100);

(b) elastomeric joint seals are to have product certification (ISO Type 5) to AS 1646;

(c) all products are to be marked in accordance with the certification body’s requirements; and

(d) the supplier of products is to declare that products comply with the requirements specified.

(e) The supplier of products shall certify (in favour of the Principal and in a form approved by the Superintendent or otherwise required by the Contract) that products comply with the requirements specified in the Contract.



13

8.6 PVC Flexible Pipe and Fittings Where this material is employed it is to comply, unless noted otherwise, with the following requirements:

(a) flexible reinforced PVC pipe (Barfell super ultraflex 201666 or approved equivalent) is to comply with AS/NZS 2554;

(b) PVC pipe to be UV resistant; and

(c) hose clamps to be H/D stainless steel “T-Bolt” type. No worm drive clamps are to be used.

8.7 Expansion Joints

The expansion joints, for absorbing axial, angular and lateral movement, are to be manufactured on the follow basis:

Component Detail of Manufacture Bellows A240 321 Stainless steel Hardware AS 3678 Grade 250 Weld ends, all pressures A53 Grade B, standard weight Flange ends AS4087

Expansion joints supplied are to conform to the Expansion Joint Manufacturer’s Association standards and be installed in accordance with AS 1554 and AS 4041.

8.8 Metal Banded Flexible Couplings Metal banded flexible couplings shall be manufactured in compliance with AS 4327.

8.9 Pipe Installation and Jointing

8.9.1 Pressure Main Thrust and Anchor Blocks Provide concrete thrust/anchor blocks at all valves, changes in direction, termination points, tees, enlargers and reducers or any other point where unbalanced forces resulting from internal pressures will occur. Engage an independent geotechnical consultant to confirm the allowable horizontal bearing pressure (AHBP), and/or allowable vertical bearing pressure (AVBP) at each location. Adopt an appropriate factor of safety allowance for design of blocks.

The thrust/anchor blocks shall bear against undisturbed material normal to the direction of the thrust over the specified bearing area.

Cure concrete thrust and anchor blocks for a minimum of seven (7) days before subjecting to any thrust load.

Use of welded steel pipelines in lieu of thrust blocks is acceptable where bearing capacities of soil make large concrete thrust blocks impractical.

Provide temporary anchorage adequate to restrain the pipe when under test.

8.9.2 Flanged Joints Flanges to pipework, pumps, valves, flowmeter and other equipment shall:

a) be to AS 4087 Appendix D, Class 16 (compatible with Class C of AS 2129), select bolting in



accordance with AS4087 Appendix C.

b) be full face;

c) be drilled off centre to Table C drilling, and

d) have 3mm thick insertion rubber gaskets, except where 'O' rings are fitted.

Use washers under all nuts. In addition, use washers under bolt heads for connection to items with protective coatings.

Where dissimilar metals would otherwise be in contact, supply and install high strength phenolic insulating washers and sleeves to all connections.

All bolts, nuts and washers for flanges are to be grade 316 stainless steel and in accordance with AS2528.

Apply "Loctite" nickel anti seize thread lubricant or equivalent to all stainless steel fasteners prior to fitting nuts.

8.9.3 Dismantling / Expansion Joints Dismantling / expansion joints shall be:

a) of the integrally cast puddle flange type for thrust and non-thrust bearing dismantling joints; and

b) such that the pipework and loose flange ‘O’ ring joint can be tightened independently.

c) UniFlanges, Adapta-Flanges or similar joints secured by set screws shall not be used.

8.9.4 Connections for Pipework and Fittings Use victaulic couplings where mechanical pipe couplings are intended to take tension.

Connect pipelines to structures so that two flexible joints are provided within 900mm each side of the structure. Pipes and fittings encased in concrete are considered as structures.

8.10 Construction of Piping through Walls Where pipes pass through outside walls or walls into tanks below the water surface, extreme care is to be exercised to ensure joints being watertight. All pipe to be embedded in the concrete are to free of all dirt and grease prior to placement of the concrete to secure a tight bond with the concrete. All pressure pipelines cast into concrete structure are to be fitted with a thrust bearing puddle flange located centrally in the concrete structure.

8.11 Initial Testing of Gravity Pipelines Only Undertake initial testing of pipelines before commencing backfilling. Undertake initial testing of access chambers before rendering of the channels and benching. Ensure that pipes and access chambers are clean before any test is performed.

If any of the tests prove to be unsatisfactory, detect and repair the fault



15

and then re-test. Continue to repair and re-test until a satisfactory test is obtained. Even if initial testing produces satisfactory test results, repair any structure, pipeline or conduit in which there is a visible or detectable leak or blockage. The initial testing of pipelines may be performed before risers and sidelines are constructed provided such risers and sidelines are tested separately prior to being backfilled. When a trench support system is used which requires progressive backfilling, initial testing may be performed after backfilling but at the completion of each pipeline length or at the end of each day's work for uncompleted lengths and provided that the cause of any initial test failure is immediately located, repaired and the line re-tested.

Undertake initial testing comprising:

(a) Check the degree of compaction of the underlay and any side support, the line and grade of the pipeline and that pipe joints have been made to the manufacturer's witness marks.

(b) Air testing in accordance with clause 2.13 below.

8.12 Air Testing Supply and maintain all necessary equipment in a condition which is fit for its intended purpose. Supply air with a compressor capable of supplying at least 1 m3/minute at 35 kPa. Feed air through a pressure reducing valve capable of reducing pressure to 28 kPa +/- 4 kPa, an airtight line fitted with two 150mm Bourdon type pressure gauge reading from 0 to 50 kPa, a pressure relief valve that may be set to blow off at 32 kPa and a gate valve to the pipeline to be tested. Use pressure gauges which have been calibrated within three months of the testing. The gauges must read within 2 kPa of each other for 28 kPa tests. Use the gauge reading the lower for the readings.

Perform testing as follows:

(a) Insert a plug in one end of the line to be tested and a disc with air-hose connection at the other end. Ensure that the force due to the pressure on the disc is not taken by pipe joints, but is taken by struts bearing on the disc or on the end pipe in the line.

(b) Connect test equipment and carefully increase the air pressure to 28 kPa over approximately one minute. If the pressure cannot be raised to 28 kPa, the test is unsatisfactory.

(c) Hold the pressure at 28 kPa for three minutes to stabilise the temperature.

(d) Shut off the air supply and measure the time taken for the pressure to drop from 25 to 18 kPa. The test is unsatisfactory if this time is less than as tabled below;

Nominal Pipe Size

(mm)

Minimum acceptable time for pressure drop 25 to 18 kPa

(min)

150 2

225 4

300 6

375 8

400 9



450 11

525 14

Where a satisfactory test cannot be achieved and there are no visible leaks, undertake hydrostatic testing in accordance with this Specification.

8.13 Hydrostatic Testing Undertake hydrostatic testing as detailed below:

(e) Connect to the pipeline, a pipe or hose terminating in a 150mm diameter container not less than 100mm deep. Plug all other open ends of the pipeline.

(f) Fill the pipeline with clean fresh water until the container is full when suspended a minimum of two metres above the highest invert of the line under test, including any risers and sidelines, or two metres above the free standing level of ground-water in the vicinity, whichever is greater.

(g) After allowing an interval for absorption of between two and ten minutes, make up any fall of the free water surface by adding water to the container and then measure the fall in water level during ten minutes thereafter.

The pipeline shall be regarded as having passed the test if there are no visible leaks and if the fall in water level is not more than 25mm for each standard test length of the pipeline under test including risers and sidelines.

8.14 Acceptance Testing of Gravity Pipelines Undertake air testing in accordance with this Specification. Where a satisfactory test cannot be achieved and there are no visible leaks, undertake hydrostatic testing in accordance with this Specification.

The prover shall have pulling rings at each end and be marked to indicate the nominal pipe size and the prover outside diameter. The prover shall be drawn through the pipeline no sooner than 28 days after completion of placement and compaction of trench fill.

Uncover any pipes failing the deflection test, recompact the side support fill, reinstate the backfill and retest for deflection.

8.15 Hydrostatic Acceptance Testing of Watermains, Sewer / Sludge Rising Mains The hydrostatic test pressure is taken as the design pressure and shall not exceed this by more than 25%.

The maximum loss rate is given by;

( 0.14 x N x L x H ) / 1000 (litres per hour)

where: N = nominal size of pipe (mm)

L = length of pipeline under test (km)

H = average value of test pressure (m)



17

Testing is to be carried out using a testing rig which has two calibrated pressure gauges. Use pressure gauges which have been calibrated within three months of the testing. Both gauges must read within 5% of the test head and 5% of each other. Use the gauge reading the lower for the readings. Before testing a pipeline section, it should be cleaned and then slowly filled with water, ensuring that air has been completely expelled.

Perform testing as follows:

(h) Pressurise the line to 75% of the test pressure and leave for a minimum of twelve hours.

(i) Provided there is no obvious leak in the pipeline, steadily raise the pressure in the pipeline until the specified test pressure is reached.

(j) Maintain this pressure for a minimum of four hours. Measure and record, at half hour intervals, the quantity of water added in order to maintain the pressure during the period of testing.

(k) During the pressure testing of the pipeline, ensure each valve sustains at least once the full test pressure on one side of the valve closed position with no pressure on the other side for at least fifteen (15) minutes.

(l) Visually inspect the line for leaks. If a leak is suspected but is not visible use aural or electronic assistance.

The pressure testing on a section of pipe is deemed to be satisfactory if:

(m) there is no failure of any thrust block, anchor block, pipe, fitting, valve, joint or any other pipeline component;

(n) there is no visible leakage; and

(o) the average measured leakage rate during the last four hours of the pressure testing does not exceed the maximum loss rate as determined in accordance with the process set out above.

Any failure, detectable leakage or other Defect occurring or detected during pressure testing shall be remedied and the pipeline will be retested.

9 DISINFECTION

9.1 General Disinfect all potable watermains and tanks by using a disinfectant added to water drawn from the water distribution system before they are placed in service.

During the disinfection process:

• operate all valves, hydrants, water meter ball valves (where fitted) and other fittings to ensure complete disinfection; and

• take measures to protect the environment. When using, handling and storing disinfecting agents comply with Legislative Requirements.

Take one sample of water from the new pipework /tank and analyse

9.2 Flushing of Disinfection Water Dispose of disinfected wastewater in accordance with the Superintendent’s requirements. Based on the results of the bacteriological tests the Superintendent may allow disinfected water to be discharged into the distribution network. Otherwise take all necessary steps to ensure that disinfected water used



in the disinfection process does not enter the distribution system.

Scour and flush mains at the earliest opportunity following the minimum contact period.

9.3 Bacteriological Test Disinfection of the new filtered water main shall be required to ensure suitable water quality parameters are maintained. Undertake bacteriological testing of the disinfected water following satisfactory completion of swabbing/flushing and pressure/water testing.

Test as follows:

• engage a NATA registered laboratory to collect representative water samples; and

• dispose of testing water in accordance with the relevant environmental Authority and/or water Authority requirements.

Conduct bacteriological tests in accordance with Standard Methods for the Examination of Water and Wastewater, APHA, 20th Edition, Section 9222 and/or AS 4276, as appropriate.

Accept results:

• if the test results fall within the water quality parameter limits specified in the table below:

Water Quality Parameter Unit Acceptable Range

Total coliform count Cfu/100mL 0

Faecal coliform count or E.Coli count

Cfu/100mL 0

Heterotrophic plate count Cfu/mL 0-10

• if the water quality parameter test results are no worse than the water quality parameter test results measured by testing an influent sample of existing mains water, by the NATA registered lab.

10 STAINLESS STEEL PIPEWORK HOLD POINTS

(i) Design submission

(ii) Contractor’s submissions and qualifications of inspection personnel

(iii) Material validation and traceability through to the completion of fabrication

(iv) Post fabrication testing and inspection

(v) Hydrostatic testing

[END OF ADDENDUM]