gs6 knf expansion process equip

EXPANSION OF KRANJI NEWATER FACTORY

GENERAL SPECIFICATION G6

Process Equipment

CONTENTS

G6.1 PROCESS EQUIPMENT ............................................................................................................ 1

G6.1.1 General ....................................................................................................................... 1

G6.1.2 Statutory Requirements and Standards ....................................................................... 1

G6.1.3 Technical Requirements .............................................................................................. 1

G6.1.4 Pumping Equipment .................................................................................................. 10

G6.1.5 Submersible Pumps ................................................................................................... 12

G6.1.6 Centrifugal Pumps ..................................................................................................... 18

G6.1.7 Compressed Air Systems ........................................................................................... 26

G6.1.8 Blower Air Sytems ..................................................................................................... 34

G6.1.9 Process Pipework ...................................................................................................... 49

G6.1.10 Valves ....................................................................................................................... 57

G6.1.11 Actuators and Controls .............................................................................................. 61

G6.1.12 Corrosion Protection ................................................................................................. 63

G6.1.13 Lifting Equipment ...................................................................................................... 66

G6.1.14 Handrailing................................................................................................................ 67

G6.1.15 Fixed Platforms, Walkways, Stairways and Ladders ................................................... 67

G6.1.16 Ladders ..................................................................................................................... 68

G6.1.17 Electrolytic Action ..................................................................................................... 68

G6.1.18 Cleaning on Completion ............................................................................................ 69

G6.1.19 As Constructed Details .............................................................................................. 69

G6.1.20 Drawings ................................................................................................................... 69

G6-i


G6.1 PROCESS EQUIPMENT

General

This specification defines the general mechanical requirements for equipment supplied for the Expansion of Kranji NEWater Factory.

This Specification covers general mechanical requirements for the design, supply and installation, testing and commissioning of mechanical equipment and is intended to be used together with the Particular Specifications for mechanical and process components.

All equipment shall be provided complete with all minor and incidental items necessary for the proper functioning of the whole system, even though not specifically detailed or mentioned.

Statutory Requirements and Standards

The design, manufacture, supply, storage, installation, testing and commissioning of all mechanical equipment shall comply with all latest relevant Singaporean or British Standards, or in the absence of, the appropriate American, Australian, European or International Standards, Acts and Regulations shall apply, in their latest amendment.

The Standards referenced shall form part of this Specification. Other Standards, Codes of Practice and Statutory Regulations not referred to, but which would be applicable to the design, manufacture, installation, testing or commissioning of the equipment under this Contract shall be deemed to be part of this Specification.

Technical Requirements

(i) Corrosion Control and Protective Coatings

1) All items of mechanical equipment shall have protective coatings in accordance with the requirements of the Specifications.

2) Where mating machined ferrous surfaces are in permanent, static contact after assembly each shall immediately before assembly, be uniformly coated with a thin mixture of graphite in oil, or other approved proprietary anti-seize compound.

3) Liner and wear plates shall not be coated, however ferrous mounting surfaces for liner and wear plates shall be coated.

4) Proprietary items may use standard factory applied coating systems only where the S.O. has approved these systems.

5) Where the manufacturer of electrical or mechanical equipment supplies the product with a standard factory supplied coating system, this may be accepted by the S.O. provided the coating is considered to be equivalent or better in performance than that specified for the application and provides the necessary design operating life of 15 years minimum. Where the S.O. considers that the factory-supplied coating is unsatisfactory, the coating may be either:

• Removed and repainted as per the original coating specifications, or • Upgraded by the application of an approved additional paint coating.

G6-1 PROCESS EQUIPMENT


Packers and Shims

(i) All packers and shims used in the levelling of equipment shall be made from uncoated new material only, having flat surfaces free from indents or burrs.

(ii) Shims shall completely cover the mating faces. Edges shall not protrude beyond the mating surfaces.

Guards

(i) Metal safety guards shall be fitted to all exposed moving parts and nip points.

(ii) The guards shall conform to the requirements of the Statutory Authority, to AS 1755 and to AS 4024.1 or equivalent British Standard.

(iii) Adequate protection shall be provided over motors, thrusters, limit switches, cables, lighting fittings, chemical dosing lines etc. to protect them from mechanical damage and build-up of material. Spillage plates shall be provided where necessary to reduce build-up on structural ledges or machinery components.

(iv) Guards (or guard components) shall be readily removable by one man without the use of tools, and so arranged as not to restrict access to bearings or other items requiring ready access. Where applicable, and subject to ease of handling, guards may be hinged to form gates.

(v) Guards shall be fabricated with inspection ports or shall be fitted with expanded metal sections to allow inspection without having to remove the guards.

(vi) All guards shall be rigidly supported and be arranged for easy removal and replacement without dismantling other parts.

(vii) Solid guards shall be made from galvanised sheet metal having a minimum thickness of 2 mm. Mesh guards shall be made from double-crimped galvanised wire mesh of no less than 4 mm diameter, and secured to the inside of a galvanised steel frame. Meshes and grids shall be reinforced around the edges and bolted into position. Wing nuts shall not be used. Guards shall be hot-dip galvanised after fabrication, with further protection as appropriate, in accordance with the specification for corrosion protection.

(viii) Guards on V-belt drives shall provide for all belt take-up requirements and shall incorporate wire mesh side panels to allow visual inspection of the belt drive without the need to dismantle the guard.

(ix) Inspection covers shall be readily opened without the use of tools. Grilles, bars or mesh shall be provided behind covers where moving equipment may be reached. Alternatively, interlocks shall be provided to stop equipment in the event that covers are opened.

Bearings

(i) All ball or roller bearings shall be rated in accordance with AS2729 "Rolling Bearings Dynamic Load Ratings and Rating Life - Calculation Methods" with factors a1, a2 and a3 equal to one (1) to give a B10 life of 100,000 hours.

(ii) All bearing housings shall be fitted with seals and shall be grease lubricated. Bearing housings shall be fitted with grease pressure relief devices to prevent overpressure.



(iii) Plain bearings shall have steel shafts running in bronze bushes and shall have a loading, based on projected area, of not more than 300 kPa. Materials other than steel and bronze may be accepted where full details are submitted by the Contractor and approved by the S.O.

Lubrication

(i) All mechanical equipment shall be furnished with the correct lubricants to prevent corrosion during storage and installation and for starting and commissioning the plant, unless specified otherwise. Lubricants shall be as recommended by the equipment manufacturer.

(ii) All grease-lubricated anti-friction bearings that are not of the sealed-for-life type or automatically lubricated, and all other manual greasing points, shall be fitted with grease nipples. Grease nipples shall be of the hydraulic type and shall be zinc- or cadmium-plated steel.

(iii) Grease nipples shall generally be fixed directly onto the equipment, however where the greasing point would be out or reach from the normal pedestrian access or enclosed behind guards, then grease lines shall be run to an accessible location and terminated on a securely fixed and labelled plate. Where there are two or more greasing points in close proximity that are not accessible, grease lines shall be run to a central location and grouped together on a single labelled plate. The length of any grease line shall not exceed 6 metres.

(iv) Grease lines shall be made from 6 mm diameter grade 316 stainless steel.

(v) Grease lines shall be located so that the temperature of the line does not exceed the grease manufacturer’s recommendations for maximum storage temperature.

(vi) Grease lines shall run along and be firmly attached to the structural steel work, and shall be located to afford the best possible protection from mechanical damage during maintenance and overhaul activities.

(vii) Before connection to the item of plant, grease lines shall be pumped full of the specified grease and additional grease pumped through to clear the line of any dirt or swarf.

(viii) Where used, flushing oil shall be compatible with the running oil. Flushing oil shall be appropriately disposed after flushing.

(ix) Any oil-lubricated machinery having an oil collection sump shall be fitted with a fill plug, drain plug with magnetic insert, and oil level indicator. Oil lubricated machinery employing an oil pump shall incorporate a replaceable oil filter and pressure gauge.

(x) All lubrication and oil fill points shall be labelled to specify the type of lubricant used and the quantity required. A nameplate shall be provided at each remote lubrication point to indicate the item it serves. Plates shall be engraved stainless steel grade 316, fastened with stainless steel screws.

Signs and Labels

(i) Signs and labels shall be supplied and fitted as required by any applicable standard, code or regulation.



(ii) All safety and warning signs shall be supplied and installed where necessary and shall comply with any applicable standard, code or regulation.

(iii) The signs shall warn of potential hazards, assist in preventing accidents and give operational and emergency procedures for potentially hazardous situations. Signs shall provide warnings where equipment may start automatically, where equipment may move without warning and where other potential hazards may occur.

(iv) The contents of piping, conduits and ducts shall be identified as per AS 1345 or equivalent British Standard.

(v) Permanent labels shall be fitted to all major items of equipment. Each item of equipment shall be clearly labelled with its equipment number, which shall be in a readily discernible position. Numbering systems shall be in accordance with the numbers supplied on the equipment data sheets, P&ID’s or other referenced drawings.

(vi) The labels for major equipment (prefixed ME, PF, PV and TK etc) shall be of engraved stainless steel and shall show the equipment number in alpha- numeric block capitals, not less than 3mm line thickness and 25 mm high, filled in black.

(vii) Labels for valves and instruments (prefixed CV, V, RV etc or instrument) shall be a W/B/W traffolyte label 90mm x 40mm, engraved with the equipment number in 16mm alpha-numeric block capitals, pop riveted to a 100mm x 50mm x 2mm thk aluminium backing plate.

(viii) The extent and type of labels shall be generally consistent with existing practice on the Site, with the following minimum requirements for identification labels:

1) All marking shall be permanent, in the English language and all values shall be in SI units.

2) All items shall be marked with the nominated identification number.

3) All markings shall be able to be read from a distance appropriate to the function.

4) All labels shall be attached to a principal component so that they are not discarded with a replacement part.

5) Where equipment is submerged or fully enclosed, additional identification labels shall be located adjacent to that equipment.

(ix) All proprietary items shall be fitted with technical labels in addition to the identification labels, positioned such that they can be clearly read after installation Such information shall include as a minimum, the following:

1) the manufacturer’s or agent’s name and address

2) the model number or serial number (where applicable)

3) the total mass of the item

4) the type and quantity of any lubricant required

5) other technical data relevant to the component e.g. capacity, rating, speed, ratio, torque, power, voltage etc



Fasteners

(i) Bolts with hexagon heads and hexagon nuts shall be both manufactured from Grade 316 stainless steel. Flat stainless steel washers shall be provided with each bolt and nut set. Bolts and nuts shall comply with the relevant sections of BS EN 1092 and BS 4190 “ISO Metric Black Hexagon Bolts, Screws and Nuts”.

(ii) All fasteners such as screws, bolts, nuts and washers shall be of corrosion resistant material such as stainless steel, galvanised steel or brass. Zinc plated bolts; screws etc shall not be used.

(iii) On mechanical equipment and associated pipework in contact with the fluid, fasteners shall be grade 316 stainless steel.

(iv) Grade 316 stainless steel fasteners shall be provided for the connection of stainless steel pipes and buried liquid lines. Associated nuts and washers shall be Grade 316 stainless steel.

(v) Bolt length shall be such that after joints are made up, the bolts shall protrude through the nut, but not more than 12 mm.

(vi) All bolt threads shall be smeared with a nickel based anti-seize compound prior to assembly.

(vii) Barriers between dissimilar metals shall be installed (e.g. unicashion, fibre washers sleeves etc).

(viii) On structural components, e.g. walkways, handrails, fasteners shall be hot dip galvanised.

(ix) On commercially supplied mechanical equipment such as motors, gearboxes, pumps, conveyors, etc. all fasteners which are not of corrosion resistant materials shall be replaced with fasteners which comply with this specification.

(x) Where bolted connections are subject to vibration, self-locking nuts shall be used.

(xi) Drilling of bolt holes shall be accurate and any slight misalignment in the matching of holes may be corrected by reaming. Where excessive misalignment occurs, the holes shall be filled by electric welding and redrilled. Drifting to enlarge or draw unfair holes will not be permitted.

Equipment Maintainability

(xii) All equipment shall be configured to maximise both operator safety and maintainability.

(xiii) All proprietary items, and other items requiring removal for maintenance, that have a mass of more than 70 kg, shall have clearly designated lifting points suitable for shackle or sling attachment.

(xiv) The following items shall have lifting handles (one handle if having a mass less than 20 kg, two handles if having a mass between 20 kg and 70 kg):

1) guards

2) removable panels, hatches and walkways (handles recessed if appropriate)



Alignment and Settings

(i) The installed alignments, fits, pre-tensions, float, and settings on all items of equipment shall be in accordance with the manufacturer’s written instructions.

Installation Procedures

(i) The installation of all mechanical equipment shall be carried out in accordance with the manufacturer’s Installation Procedures.

(ii) The Installation Procedures shall include:

1) A method statement for each component of equipment to be installed, with particular reference to any downtime on existing equipment and the proposed corresponding equipment preparation.

2) Documentation of the size and load limitations applicable to all equipment to be installed, with respect to the intended transportation route on Site.

3) The proposed lifting arrangement.

(iii) Schedules tabulating the settings and accuracies required for the installation of the various items of equipment. These schedules shall separately list Required Values and Measured Values. The measured values recorded during installation shall be signed and submitted to the S.O. as part of the ITP’s.

(iv) A list of equipment and instruments used for checking settings and accuracies.

Preparation of Equipment

(i) Installation of equipment shall be based on minimising downtime on existing equipment, where it affects such equipment.

(ii) As much preparation as is practical shall be carried out on new equipment prior to installation.

Equipment Protection

(i) All equipment on site shall be stored and protected in accordance with the manufacturer’s recommendations and the equipment’s functional requirements.

Grouting of Steelwork and Mechanical Equipment

(i) Concrete surfaces and anchor bolt pockets shall be thoroughly cleaned before placing grout.

(ii) Bases of equipment shall be designed or filled in with grout so as not to create pockets in which dirt and/or water could collect and cause corrosion and so that cleaning around the equipment can be easily carried out.

(iii) The minimum grout thickness shall be 25mm unless specified otherwise on the drawings.

(iv) Grout shall completely fill the anchor bolt pockets and space under the base plate.

(v) Grout shall be packaged non-shrink flowable grout with a minimum compressive strength at 28 days of 50MPa. The grout shall be stored, mixed and installed in accordance with the manufacturer’s recommendations.

(vi) The grouting shall not be carried out if the temperature of the base plate or footing surface is above 38°C.



Baseplates

(i) Baseplates for motor driven plant shall hold both the driver and driven units. Sub-baseplates shall be welded to the main baseplate.

(ii) All items mounted on baseplates shall be fixed with precision fitted bolts or studs.

(iii) Baseplates shall have sufficient rigidity to support the equipment mounted on it during handling (where applicable) or use, without distortion or deflection that could permanently damage the equipment or baseplate.

(iv) Baseplates shall be sufficiently rigid and designed so as not to deflect under all operating loads imposed by adjoining pipework or equipment.

(v) Eye bolts or lifting lugs/holes shall be provided for lifting the complete assembly on the base plate in addition to lifting facilities on the individual components.

(vi) Provision shall be provided on all baseplates to enable them to be completely filled with grout during erection where specified.

(vii) All baseplates, pipe supports and other items fixed to the concrete foundation shall have straight smooth sides.

(viii) Flame cutting shall not be used to form holes in steelwork for bolts and fasteners.

(ix) All bolt holes in steelwork shall be a distance of not less than 1.5 x hole diameter from the nearest metal edge, unless otherwise specified.

(x) Flexibly mounted equipment shall be provided with suitable snubbers with resilient surfaces to limit seismic movement.

(xi) Frame members, if constructed from hollow sections, shall have ends closed off and be fully sealed against ingress of moisture. Galvanised hollow frame members shall have bleed holes fully sealed after being galvanised.

(xii) All galvanised items shall be detail designed in accordance with the Galvanisers Association of Australia Manual to optimise the effectiveness of the galvanising protection system.

Speed Reduction Gearboxes

(i) Each speed reduction gearbox shall be designed to operate continuously at maximum duty with a minimum service factor of 1.4 based on maximum operating torque. In addition each gearbox shall be designed to withstand starting torques of up to 250% of the full load running torque of the driving motor. Each gearbox shall be a double or triple reduction unit with helical gears.

(ii) Gear housings shall be of high-grade iron in two piece construction with a top cover for ease of inspection and maintenance.

(iii) The housings shall have ample internal ribs for rigidity with the direction of rotation of input and output shaft permanently marked on the housing. Removable gasketed inspection covers shall be provided to permit inspection of the gears without disassembly of the gear reducer. Lifting lugs shall be provided to facilitate safe lifting of the gearbox.

(iv) Gears, pinions and shafts shall be made from alloy steels. The gears and pinions shall be through hardened, induction hardened or carburised and shall be designed to have a service factor for both durability and strength of at least 1.4. The gears shall satisfy the requirements of AGMA.



(v) The gears shall be splash lubricated from a sump. The bearings shall be either splash lubricated or grease lubricated. Where grease lubricated bearings are fitted, seals shall be installed to retain the grease in the housing. Grease nipples and grease relief devices shall be fitted to housings containing grease-lubricated bearings.

(vi) The unit shall be provided with sight glass or indicator to observe oil levels. All oil fill and drain lines shall be of sufficient size to permit efficient functioning and shall be located on the gear unit in a position which is easily accessible from the floor. All oil and drain piping shall be supplied so that a container may be placed under the drain discharge.

(vii) All external nuts, bolts and studs on the gearboxes shall be of stainless steel grade 316.

Anchor Bolts

(i) All anchor bolts, nuts and washers for mounting mechanical equipment shall be designed and supplied under this Contract. The anchor bolts, nuts, washers shall be manufactured and sized for the duty required. Chemical set fasteners shall be used.

(ii) All anchor bolts, nuts and washers etc shall be manufactured in 316 stainless steel (this does not include structural steel). Zinc plated or black bolts, screws etc., shall not be used.

(iii) All anchors shall be installed in accordance with the manufacturer’s directions.

(iv) Abandoned drill holes shall be thoroughly cleaned and filled with epoxy grout such that the drilled material is returned to a homogeneous state with all the same characteristics prior to the holes being drilled.

(v) Where the relocation of masonry anchors necessitates alteration to steelwork base plates, the Contractor shall determine all additional stiffening or strengthening of the base plate and adjacent steelwork required. The additional buildup of members shall comply with the structural steel designers recommendations and be approved by the S.O.

Stainless Steel Fabrications

(i) General

1) All fabricated stainless steel shall as a minimum be grade 316L.

2) All welding shall comply with the requirements for Welding of Austenitic Stainless Steel Tube and Pipe Systems in Sanitary Applications as specified by the American Welding Society AWS D18.1:1999. The Contractor shall arrange for the S.O. or a nominated representative to inspect and approve the welding work prior to acceptance.

(ii) Passivation

1) All stainless steel fabrications shall be passivated after all welding has been completed. Passivating preferably shall be carried out in the fabricator's works.



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

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

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

5) Where passivation on site is unavoidable it shall be carried out in accordance with the Manufacturer's instructions. No waste shall be flushed down plant pipes or into sewer or waste collection sumps, but shall be collected and suitably disposed of (off site) by the Contractor.

(iii) Contamination

1) Care shall 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.

2) Particular practices that are unacceptable are:

• Cleaning with steel wool, wire brushes, emery paper • Cleaning with abrasive compounds containing chlorides • Blast cleaning • Using muriatic (i.e. hydrochloric) acid as used in solder fluxes as it

contains iron Noise

(i) All mechanical equipment (pumps, compressors, blowers etc) including the drive unit, shall satisfy all noise regulations and the following:

1) The overall Sound Pressure levels of any equipment or process unit shall not be exceeded 80 dB(A) when measured at no further than 1 metre from the operating unit when operating at full load. If equipment does not meet the specified Sound Pressure Levels, appropriate action to reduce the noise levels shall be implemented.

2) Appropriate measures shall include acoustic attenuates or enclosures provided by the Contractor to reduce the noise levels and meet the noise criteria above.



3) Specific equipment may require lower noise levels. These will be indicated in the individual equipment specifications and/or Technical Specifications. Which have precedence over the values given above.

Pumping Equipment

General

(i) ll pumps of the same type (ie submersible, centrifugal, progressive cavity, etc.) shall where possible be of the same manufacturer.

(ii) Pumps supplied shall be capable of satisfying the performance requirements specified.

(iii) Low maintenance costs, reliability and trouble free operation will be prime considerations when selecting pumps.

(iv) Pumps shall be quiet in operation and free from vibration.

(v) Each centrifugal pump shall be provided with air release valve and pipe. The air release pipe shall be mounted at the top of the pump casing or delivery branch. The automatic air release valve shall be fitted at a position convenient for maintenance.

(vi) Pump casings shall be pressure tested in accordance with the latest British Standards (B.S.) requirements and test pressure shall not be less than 1.5 times the shut off head of the pump.

(vii) Details of pump plinths shall be provided by the Contractor and they will be cast-in-situ. The pump stools or base plates shall be bolted and grouted to the concrete plinth.

(viii) Exposed shaftings and all moving parts are to be completely protected by galvanised steel guards, securely fixed and supported. The guards shall be of approved design and manufacture.

(ix) Pressure gauges with isolating valves shall be fitted on each pump delivery and vacuum gauges on each pump suction.

(x) The suction pipework and wet well arrangements shall be designed to avoid prerotation in the suction pipework and pump inlet and present a good flow pattern at the entrance to the impeller.

Factory Performance Tests

(i) Each pump casing before assembly shall be subjected to a hydrostatic test pressure of 2 times the shut off head. During the test, the casing and joints shall show no sign of leakage, distortion or defect. If required by the S.O. or his representative, the pump casings shall be made available for dye penetration test, or radiographic tests or both, before or after application of hydrostatic tests, by a mutually acceptable testing laboratory.

(ii) Factory performance tests shall be carried out to confirm that the each pump fully complies with the specifications and the specified duty and performance requirements.

(iii) Each pump shall be tested with its own Contract motor under the minimum suction level conditions at which it will operate when installed on site.



(iv) Testing procedures shall be in accordance with the requirements of AS 2417, Part 2 - class C (or equivalent), and shall be carried out over the complete operating range of the pump.

(v) Pumps driven by variable speed electric motors shall be tested at five (5) different speeds so that a range of performance curves can be generated. The speeds shall be approximately equally spaced from the minimum to the maximum speeds necessary for the specified duty.

(vi) The S.O. or his representative shall be informed in writing four weeks prior to the intended date of performance tests. The performance tests shall be witnessed by the S.O. or his representative.

(vii) Each pump shall be tested and a copy of all readings taken, copies of all calculations and certified pump performance curves shall be submitted to the S.O. or his representative.

(viii) The pump performance curves shall show plots of the following:

1) Total discharge head versus flow;

2) Pump efficiency versus flow;

3) Input power absorbed versus flow; and

4) Net positive suction head versus flow.

(ix) To plot these curves, readings shall be taken at a minimum of three points in addition to the shut-off condition. In addition to the above test, each pump shall be run at its duty point for at least 15 minutes.

(x) The above tests shall also establish that the pump is free from overheating/cavitation and excessive vibration over the entire range of flows.

(xi) Should the performance tests show that the performance of any pump-set is less than the guaranteed performance stated in the Technical Schedules, then that pump-set shall be rejected. The pump may be modified in a manner approved by the S.O. or his representative after which it shall be retested. If on retesting, the performance is still less than the guaranteed performance, the pumps shall be rejected.

(xii) The acceptance of the results of performance tests of the pump-set by the S.O. or his representative shall in no way be construed as being final acceptance or as relieving the Contractor of responsibility for the pump-set and associated system design and performance. The pumps and motors shall only be shipped after satisfactory completion of all factory performance tests and all results and reports have been submitted to the S.O.

Hydrostatic Tests

(i) All piping and fittings after assembly shall be subjected to a hydrostatic test pressure of 1.5 times the operating pressure.

(ii) During the test, all piping and joints shall show no sign of leakage, distortion or defect.

Testing of Pumps at Site

(i) After installing the pump-set at site, the pumps, motors, drive couplings etc which together form the pump sets shall be:



1) Rigidly bolted down to support floors, plinths, etc;

2) Properly and accurately aligned; and

3) Run freely without noticeable noise and vibration.

(ii) Under all operating conditions, the pumping equipment shall be capable of:

1) Pumping continuously and reliably without requiring continuous surveillance;

2) Operating quietly, without noticeable vibration and without cavitation, single or in any combination from minimum to maximum operating levels as specified or operating against closed delivery valve at shut off head.

(iii) The S.O. shall reject any pump set during the tests if:

1) It fails to pump under normal operating conditions reliably and without vibration and cavitation; or

2) It fails to comply in any other respect with the requirements of the specifications.

(iv) After each pump has been tested individually, all level controls and interlocks shall be set at the levels specified and shall operate the system to demonstrate that it operates in the manner specified.

Submersible Pumps

General

(i) This section describes the minimum requirements for the design, supply and testing of submersible centrifugal pumps and appurtenances for both dry well and wet well installations.

(ii) The duty specifications (eg. flow, head, NPSHA, fluid properties and other particular requirements) for individual pumps shall be as specified.

(iii) Where specified, submersible pumps shall be suitable for dry well installation.

(iv) All pumps shall be complete with all minor and incidental items necessary for the proper functioning of the equipment, even though not specifically detailed.

(v) This Specification shall include all Technical Schedules, Technical Information and drawings as applicable to the pump requirements.

Standards

(i) This Specification shall be read in conjunction with any Standards referenced, which are deemed to form a part of this Specification. All materials, equipment and workmanship shall comply with these Standards, or other industry recognised standards in the absence of specified standards, unless expressly noted otherwise.

Submersible Pump Design and Duty Requirements



(i) Submersible pumps shall be of a standard and proven design and shall be single stage, centrifugal type, directly coupled to a motor forming a compact, robust and completely watertight pumping unit. The lubrication of both pump and motor shall be of a modern design of sufficient capacity to operate for long periods without attention. The whole unit shall be resistant to severe corrosion associated with sewage or effluent pumping.

(ii) The pumps shall be designed and sized for the required duties, including flow ranges, fluids, temperatures and pressures specified and shall comply with the following requirements:

1) Provide continuous operation at the duty points specified and at any other points within the specified operating range.

2) Provide the required turndown and be capable of accurately pumping, without overload over the complete specified flow range.

3) A maximum speed that does not exceed 1500rpm. The operating speed shall be as recommended and specified by the manufacturer as suitable for the properties of the material being pumped and the materials selected for the pump.

4) Operate at high efficiency with the specified duty point as close as possible to the best efficiency point of the pump.

5) Provide a design life of 20 years.

(iii) Pumps shall be readily removable for inspection and maintenance, without the need for personnel to enter the tank/wet well, using the dedicated lifting equipment.

(iv) The pumps shall comply with the noise requirements specified.

(v) The Contractor shall submit to the S.O. the maximum noise level of each complete pump and motor assembly, under all operating conditions.

(vi) Pumps shall be equipped with a vented jacket cooling system, which shall provide a continuous circulation of pumped cooling media.

(vii) Pumps shall be of a standard and proven design for which spare parts are readily available in Singapore.

(viii) Flanges for pumps and appurtenances shall comply with BS EN 1092 Circular Flanges for Pipes, Valves and Fittings. , and shall be drilled as specified, or as necessary to suit the maximum head design condition of the pump.

Operating Conditions

(i) The required operating conditions for the pumps shall be as specified or required by the Contractor’s system design.

(ii) Whether alone or in parallel, each pump shall operate over the specified range of suction heads and discharge heads and shall be capable of operating without over-loading of the motor at any point within the range of operation.

(iii) The pumps shall be completely stable in operation at all heads and (in case of two or more units in parallel) under all conditions of single or parallel operation, within the full operating range.



Seal Failure Detection

(i) Two types of seal failure (or moisture detection) probes shall be fitted to pumps and shall be provided with the associated detection module/relay, which shall be mounted into the switchboard.

1) One probe shall be fitted in the oil bath between the two mechanical seals and shall be arranged to detect the presence of water in the oil bath, e.g. to detect failure of the impeller seal.

2) A second probe shall be fitted at the bottom of the motor casing arranged to detect any leakage of water into the motor, e.g. through cable glands or "O" ring seals.

Pump Construction

(i) Materials

1) The pumps shall be manufactured from materials selected by the manufacturer to suit the duty requirements, fluids and operating conditions.

2) The materials selected shall be suitable for the entire design life of the pump. Where specific components are subject to wear, the manufacturer shall specify the hours of continuous operation before replacement is necessary.

3) Unless stated otherwise, all materials of construction for submersible pumps shall be of materials at least equal in quality and to the minimum standards as specified in the table below:

Materials of Construction Table

A Component Material

Baseplates Cast Iron or Steel

Casings S G Iron

Impellers Cast Iron

Discharge elbows Cast Iron

Shafts Stainless Steel Grade 431

Shaft Sleeves Stainless Steel Grade 431

Sealing rings Stainless Steel Grade 431

Wear rings Bronze

Fasteners Stainless Steel Grade 316

4) Alternative materials for the pump impeller may be specified by the manufacturer, as appropriate, to best suit the pumped fluid and operating conditions and provide optimum resistance to corrosion and abrasion.

5) Alternative materials will be subject to approval by the S.O.



Casings

(i) Casings shall be designed to suit the pump, seating arrangement and service specified. For wet well installations the casing shall be designed to move up and down in guide rails and shall have provision for sealing the discharge to the discharge elbow.

(ii) Casings shall be fitted with removable inlet wear rings.

Mechanical Seals

(i) The impeller shaft shall be provided with double shaft mechanical seal, separated by an oil bath.

(ii) Mechanical seals shall:

1) Be of an industry approved standard design effective for their purpose and requiring a minimum of maintenance.

2) Be of the balanced type, with nickel bonded tungsten carbide seal faces. The seals shall incorporate bellows or multiple helical springs of stainless steel grade 316 and high nitrile synthetic rubber, ethylene propylene or ‘Viton’ rubber "O" rings as appropriate for the pump application.

3) Have faces lapped flat to within two (2) helium light bands and the depth of interface roughness shall not exceed 0.3 microns.

(iii) The pump and seal design shall be such that interface temperatures under operating conditions remain safely below the vaporisation temperature.

Impellers

(i) Impellers shall:

1) Be of an industry proven, modern design with high efficiency.

2) Be fixed to the shaft by an industry-proven method.

3) Be manufactured from material to best suit the pumped fluid and operating conditions.

4) Be fitted with replaceable wear rings.

5) Be statically and dynamically balanced.

Shafts

(i) The shaft shall be designed to withstand vibration and high speed rotation and shall be manufactured from materials selected to best suit the duty requirements, fluids and operating conditions specified.

(ii) Shafts shall be of sufficient size to limit whip or deflection and shall operate at less than 80% of their critical speed.

Namplataes

(i) All pumps shall be fitted with engraved stainless steel nameplates fastened to the pump body.

(ii) Nameplate information shall include as a minimum the manufacturer's name, address (or agent's address), model number, serial number, capacity, head, equipment identification number, contract number and date of manufacture.



(iii) The nameplates shall be permanently attached to the pump using stainless steel fixings.

Electric Motors

(i) Electric motors shall be designed to form an integral part of the pump, and shall comply with the Specifications for Electrical Works.

(ii) In addition, the motors shall:

1) Be designed for long term operation submerged at depths of up to 10m.

2) Be factory fitted with cables suitable for the purpose, of length to suit the installation and sealed to prevent the ingress of water.

3) Have a degree of protection not less than IP68 and waterproof to the required depth of operation.

4) Have an insulation of Class “F” and a temperature rise not exceeding that applicable to Class “B”.

(iii) Motor cables shall be suitable for use under water and shall have an outer sheathing to protect them from damage.

(iv) For fixed speed motors the power cable shall be a suitable rated 3-core+earth configuration.

(v) For variable speed motors the power cable shall be a suitable rated 3 core + earth configuration with overall screen.

(vi) Control cores shall not be included in the power cable of variable speed motors.

(vii) The cables shall be provided with a stranded 316 Stainless Steel supporting cable fixed to the electrical cable at suitable intervals and to the motor to prevent the cable and motor terminations from being damaged during operation or removal.

Variable Speed Drives

(i) Variable Speed Drives shall be in accordance with Specifications for Electrical Works.

Installation Details

(i) Installation Arrangements

1) Pumps shall be arranged for seating or installation in one of the two configurations set out below:

2) Pumps specified for dry well installation shall be provided with a 90° ductile iron suction elbow, orientated as shown on the drawings and a baseplate to allow the pump to be installed in a vertical position.

(ii) Pumps specified for wet well or sump installation shall be provided with a ductile iron duck-foot type discharge elbow which shall be capable of supporting the full weight of the pump in it’s operating position. The discharge elbow shall be designed with a seal face to allow the pump to be lifted vertically for inspection and maintenance.



Guide Bars and Guide Bar Supports

(i) Pumps for wet well installation shall be supplied with guide bars, supports and other appurtenances as required to facilitate the removal and installation of the pump from the wet well or sump.

(ii) The guide bars shall provide for alignment of and ensure correct seating and sealing of the pump to the discharge connection.

(iii) The guide bars shall be arranged to prevent binding of the pump whilst it is being raised or lowered and shall be secured with appropriate brackets in such a manner as to allow complete removal of the pump without dismantling either the pump or the guide bar system.

(iv) The guide bars and supports shall be manufactured from stainless steel grade 316.

Lifting Equipment

(i) Each submersible pump shall be serviced by a lifting davit, which shall include pedestal, mast, boom, hoist, associated lifting chains or cables, sheaves, hooks, handles and all fixings.

(ii) The reach and rotation of the boom shall be suitable for raising and lowering the pump from its installed position to a platform or floor area where it can be readily inspected or serviced.

(iii) Pumps for wet well installation shall be supplied with stainless steel lifting chains (or grade 316 stainless steel rope), of sufficient length and strength to enable complete removal of the pump from the pump well. The chain shall be attached to the pump with a stainless steel shackle, suitably isolated to prevent galvanic corrosion.

(iv) The maximum effort that is required at the hoist to raise the pump shall not exceed 135N, under the worst conditions of unseating force.

(v) Chains and shackles shall have a minimum factor of safety of ten (10).

Protective Coatings

(i) All pumps and appurtenances shall be provided with protective coatings in accordance with the specified corrosion protection requirements.


(i) Factory performance tests shall be carried out for all pumps greater than 7.5kW.

(ii) For pumps 7.5kW and below, a Type test certificate shall be provided.

(iii) Each pump casing before assembly shall be subjected to a hydrostatic test pressure of 2 times the shut off head. During the test, the casing and joints shall show no sign of leakage, distortion or defect. If required by the S.O. or his representative, the pump casings shall be made available for dye penetration test, or radiographic tests or both, before or after application of hydrostatic tests, by a mutually acceptable testing laboratory.



Installation, Testing and Commissioning

(i) All submersible pumps and associated equipment shall be installed in accordance with the design details and the manufacturer’s recommended instructions/ procedures.

(ii) After the pump has been installed the following checks shall be performed as a minimum, to confirm the satisfactory installation and construction completeness:

1) Check installation for compliance with the design, specifications and manufacturer’s instructions using available data (design drawings, manufacturer’s drawings and manuals, process and instrument drawings, schematic diagrams, connection diagrams, etc.).

2) Confirm satisfactory operation of all mechanical equipment.

3) Check alignment of all guide rails and operation of lifting gear.

4) Any other installation checks specified or recommended by the pump manufacturer/supplier.

Precommissioning

(i) Precommissioning tests shall be performed following all installation checks, to confirm the correct pump performance and operation.

(ii) The following checks and tests shall as a minimum be carried out:

1) Check direction of rotation.

(iii) Ensure that equipment operates with minimum vibration and noise within limits specified by the manufacturer and/or the Technical Schedules.

Commissioning

(i) Testing and commissioning shall be carried out to clearly demonstrate that the installed pump(s) meet the specified duty and performance requirement over the complete range of operating conditions.

(ii) Should testing show the performance to be less than specified, then all necessary changes shall be made to the equipment and installation for the performance criteria to be satisfied.

Centrifugal Pumps

General

(i) This section describes the minimum requirements for the design, supply and testing of centrifugal pumps.

(ii) The duty specifications (eg. flow, head, NPSHA, fluid properties and other particular requirements) for individual pumps shall be as specified.

(iii) All pumps shall be complete with all minor and incidental items necessary for the proper functioning of the equipment, even though not specifically detailed.

(iv) This Specification shall include all Technical Schedules, Technical Information and drawings as applicable to the pump requirements.



Standards

(i) This Specification shall be read in conjunction with any Standards referenced, which are deemed to form a part of this Specification. All materials, equipment and workmanship shall comply with these Standards, or other industry recognised standards in the absence of specified standards, unless expressly noted otherwise.

Centrifugal Pump Design and Duty Requirements

(i) Centrifugal pumps shall be of a standard and proven design and shall be single stage, end suction, vertical discharge, and horizontal spindle pumps with flanged end connections.

(ii) The pumps shall be of back pull out configuration and the design of the casings and impellers shall allow an uninterrupted flow through the pump.

(iii) The pumps shall be designed and sized for the required duties, including flow ranges, fluids, temperatures and pressures specified and shall comply with the following requirements:

1) Provide continuous operation at the duty points specified and at any other points within the specified operating range.

2) Provide the required turndown and be capable of accurately pumping, without overload over the complete specified flow range.

3) A maximum speed that does not exceed 1500rpm. The operating speed shall be as recommended and specified by the manufacturer as suitable for the properties of the material being pumped and the materials selected for the pump. In any case the maximum speed shall not exceed 1500 rpm unless specifically approved by the S.O..

4) Operate at high efficiency with the specified duty point as close as possible to the best efficiency point (BEP) of the pump.

5) Specified duty points to the left of BEP.

6) Constantly rising head to shut off

7) Provide a design life of 20 years.

(iv) The pumps shall comply with the noise requirements specified.

(v) The Contractor shall submit to the S.O. the maximum noise level of each complete pump and motor assembly, under all operating conditions.

(vi) Where sound attenuation or acoustic enclosures are required to achieve the specified noise limits, the Contractor shall provide full details, and nominate the maximum noise levels both with and without acoustic enclosures. Acoustic enclosures shall be designed, constructed and installed to allow quick and easy removal for inspections and maintenance. The design must be sufficiently robust to withstand a large number of removal and replacement operations during the life of the pump.

(vii) Pumps shall be of a standard and proven design for which spare parts are readily available in Singapore.



(viii) Flanges for pumps and appurtenances shall comply with BS EN 1092 Circular Flanges for Pipes, Valves and Fittings. , and shall be drilled as specified, or as necessary to suit the maximum head design condition of the pump.

(ix) Each pump shall be supplied completely assembled and ready for installation, with the following:

1) Electric motor, for single speed or for variable speed operation as specified.

2) Variable speed drives, (where required or specified).

3) Drive couplings.

4) Safety guards.

5) Baseplate.

6) Acoustic enclosure, if necessary, to ensure that the pump and motor comply with the noise specification.

7) All other work and equipment necessary to ensure the safe and satisfactory installation and operation of the pumps.

Operating Conditions

(i) The required operating conditions for the pumps shall be as specified or required by the Contractor’s system design.

(ii) Whether alone or in parallel, each pump shall operate over the specified range of suction heads and discharge heads and shall be capable of operating without over-loading of the motor at any point within the range of operation.

(iii) The pumps shall be completely stable in operation at all heads and (in case of two or more units in parallel) under all conditions of single or parallel operation, within the full operating range.

Pump Construction

(i) General

1) Centrifugal pumps shall be of the back-pull-out (BPO) design and shall have dimensions and minimum performance ratings to ISO 2858.

2) The pump and its drive motor shall be mounted on a common, rigid and substantial baseplate.

3) Holes drilled for anchor bolts shall not be obstructed by equipment on the baseplate.

4) Each pump unit shall be complete with drive unit, flexible coupling and appropriate guards to meet Statutory OH&S requirements and comply with Specifications.

5) The design shall allow for easy access to bearings during maintenance. Access ports shall be provided on both sides of the pump to allow the drive shaft to inspected and cleaned without having to dismantle the pump.



(ii) Materials

1) The pumps shall be manufactured from materials selected by the manufacturer to suit the duty requirements, fluids and operating conditions.

2) Special attention shall be given to the selection of appropriate materials for all pumps, and in particular the pumps that handle the RO permeate and product water.

3) The materials selected shall be suitable for the entire design life of the pump. Where specific components are subject to wear, the manufacturer shall specify the hours of continuous operation before replacement is necessary.

4) Unless stated otherwise, all materials of construction for centrifugal pumps shall be of materials at least equal in quality and to the minimum standards as specified in the table below:

MATERIALS OF CONSTRUCTION TABLE

Component Material

Baseplates Steel Galvanised

Casings Cast Iron

Impellers Aluminium Bronze or Stainless steel

Shafts Stainless Steel Grade 416

Nuts and bolts: Stainless Steel Grade 416

Studs Steel

Anchor Bolts Stainless Steel Grade 316

Guards Galvanised

5) Alternative materials for the pump impeller may be specified by the manufacturer, as appropriate, to best suit the pumped fluid and operating conditions and provide optimum resistance to corrosion and abrasion.

6) Alternative materials will be subject to approval by the S.O.

Casings

(i) Casings shall be designed to suit the pump, seating arrangement and service specified.

(ii) The fixed half of the casing shall be provided with substantial footings for bolting to the baseplate or stool.

(iii) All pockets in the casing which permit the accumulation of air shall be fitted with ball valves to allow all air to be released when the pumps are being primed. The ball valves shall terminate with female ends threaded DN 20 (AS1722 part 1) and be plugged.

(iv) Eyebolts shall be provided for lifting purposes.



(v) Sealing rings shall be constructed so that they can be easily replaced when necessary.

Mechanical Seals

(i) The impellor shaft shall be provided with mechanical seals.

(ii) Mechanical seals shall:

1) Be of an industry proven design effective for their purpose and requiring a minimum of maintenance.

2) Be of the balanced type, cartridge mounted with seal faces of ceramic material running on nickel bonded tungsten carbide. The seals shall incorporate bellows or multiple helical springs of stainless steel grade 316 and high nitrile synthetic rubber, ethylene propylene or ‘Viton’ rubber "O" rings as appropriate for the pump application.

3) Have faces lapped flat to within two (2) helium light bands and the depth of interface roughness shall not exceed 0.3 microns.

4) The pump and seal design shall be such that interface temperatures under operating conditions remain safely below the vaporisation temperature.

Bearings and Bearing Housings

(i) The pump bearings shall be grease lubricated ball and/or roller type and shall be rated in accordance with the latest revisions of AS2729 "Rolling Bearings-Dynamic Load Ratings and Rating Life - Calculation Method" with factors a1, a2 and a3 equal to one and to give a B10 bearing life of 100,000 hours at the continuous rated full load output and speed of the pump.

(ii) Bearing housings shall be of a design that permits accessible, manual grease lubrication through the bearing and shall be fitted with a self sealing grease nipple and automatic grease relief. Bearing housings shall be fitted with shaft seals to prevent the entry of dirt and moisture.

(iii) To avoid damage to bearings during transport of the pump, locking clamps (or other prior approved devices) shall be fitted to the shaft.

Impellers shall:

(i) Be of an industry proven, modern design with high efficiency.

(ii) Be fixed to the shaft by an industry-approved method.

(iii) Be manufactured from material to best suit the pumped fluid and operating conditions.

(iv) Be statically and dynamically balanced.

Shafts

(i) The shaft shall be designed to withstand vibration and high speed rotation and shall be manufactured from materials selected to best suit the duty requirements, fluids and operating conditions specified.

(ii) Shafts shall be of sufficient size to limit whip or deflection and shall operate at less than 80% of their critical speed.



Drive Couplings

(i) Flexible shaft couplings shall be provided between motor shafts and the driven shafts. Flexible couplings shall be of the cone ring type or of the flexible element type rated to suit the torque output of the motor or gearbox under all conditions of loading.

(ii) Couplings shall be installed within the alignment tolerances specified by the coupling manufacturer.

(iii) All nuts, bolts and studs on the couplings shall be of stainless steel grade 316.

Baseplates

(i) Where applicable, all motor driven equipment shall be mounted on baseplates, which shall be fabricated from mild steel sections and shall be hot dipped galvanised. Baseplates shall be supplied by the manufacturer of the particular equipment and shall be adequate for the specified duty.

Nameplates

(i) All pumps shall be fitted with engraved stainless steel nameplates fastened to the pump body.

(ii) Nameplate information shall include as a minimum the manufacturer's name, address (or agent's address), model number, serial number, capacity, head, equipment identification number, contract number and date of manufacture.

(iii) The nameplates shall be permanently attached to the pump using stainless steel fixings.

Electric Motors

(i) Electric motors shall be designed to form a complete pump unit, and shall comply with the Specifications for Electrical Works.

(ii) In Addition, The Motors Shall:

1) Have a degree of protection not less than IP55.

2) Have an insulation of Class “F” and a temperature rise not exceeding that applicable to Class “B”.

(iii) Motor cables shall be suitable for use under water and shall have an outer sheathing to protect them from damage.

(iv) For fixed speed motors the power cable shall be a suitable rated 3-core+earth configuration.

(v) For variable speed motors the power cable shall be a suitable rated 3 core + earth configuration with overall screen.

(vi) Control cores shall not be included in the power cable of variable speed motors.

Variable Speed Drives

(i) Variable Speed Drives shall be in accordance with Specifications for Electrical Works.

Protective Coatings

(i) All pumps and appurtenances shall be provided with protective coatings in accordance with the specified corrosion protection requirements.



Vibration Monitoring

(i) Pumps with motors of 11 kW or larger shall be fitted with a pair of vibration pick-up mountings (at 90° to each other) on each shaft bearing, to allow vibration measurement in accordance with AS2625 Part 2 or equivalent international standard. The vibration pick-up mountings shall be suitable for use with portable hand held transducers.

(ii) The pick-up mounting shall be readily accessible and when the motor is running without removing guards, cowlings or other components.

(iii) The pick-up mountings shall be rigidly mounted as close as possible to the bearings. Where clearance holes are necessary for the long vibration pick-up mountings, they shall have a diameter of at least 2 mm greater than the outside diameter of the mounting. If sealing of the opening is required an elastic damping material such as soft rubber shall be used.

Vibration Severity

(i) Under all operating conditions the pumps shall have a maximum vibration severity as specified by the manufacturer which has been demonstrated to result in trouble-free operation and provide a long life.

(ii) As a minimum, the vibration severity tests shall achieve a “satisfactory” result, in accordance with AS2625, under all operating conditions

(iii) The pump manufacturer shall state the vibration severity limits to which their equipment is constructed.


(i) Factory performance tests shall be carried out for all pumps greater than 7.5kW.

(ii) For pumps 7.5kW and below, a Type test certificate shall be provided.

(iii) Each pump casing before assembly shall be subjected to a hydrostatic test pressure of 2 times the shut off head. During the test, the casing and joints shall show no sign of leakage, distortion or defect. If required by the S.O. or his representative, the pump casings shall be made available for dye penetration test, or radiographic tests or both, before or after application of hydrostatic tests, by a mutually acceptable testing laboratory

Installation, Testing and Commissioning

(i) All centrifugal pumps and associated equipment shall be installed in accordance with the design details and the manufacturer’s recommended instructions/procedures.

(ii) Inspection and Test Plans (ITP's) shall be submitted to the S.O. for approval prior to any testing or commissioning.

(iii) Pumps mountings shall be packed and grouted with a minimum of 25mm non-expanding grout so that the units are level.

(iv) Following connection of piping, and before operation, the alignment of pumps and motors shall be checked.

(v) Pump flanges are not to be used to align pipework. Pipework is to be independently aligned and supported, prior to connection to the pumps.



(vi) Maximum misalignment of pump components shall not be greater than the manufacturer's recommended maximum.

Bedding and Grouting

(i) Where equipment and piping is supported by concrete, masonry or like material, it shall be set up on packing or wedges to facilitate alignment and be subsequently grouted into place with a minimum of 25mm non-expanding grout. Such packs, if permanent, shall be either of solid steel or other suitable metal. All other packs shall be removed before completion of grouting.

(ii) After the pump has been installed the following checks shall be performed as a minimum, to confirm the satisfactory installation and construction completeness:

1) Check installation for compliance with the design, specifications and manufacturer’s instructions using available data (design drawings, manufacturer’s drawings and manuals, process and instrument drawings, schematic diagrams, connection diagrams, etc.).

2) Confirm satisfactory operation of all mechanical equipment.

3) Any other installation checks specified or recommended by the pump manufacturer/supplier.

4) Check alignment of all couplings using the two-dial gauge method, or approved equivalent.

5) Following connection of piping, and before operation, realignment of pumps and motors shall be checked.

6) All nuts and bolts, securing flanges and base mounting fixtures must be checked for tightness before operation.

Precommissioning

(i) Precommissioning tests shall be performed following all installation checks, to confirm the correct pump performance and operation.

(ii) The following checks and tests shall as a minimum be carried out:

1) Check direction of rotation. The motor must be uncoupled from the pump before the direction of rotation is tested.

2) Check that lubrication of pumps is complete and correct lubricant is supplied in correct quantities.

3) Check that all moving parts are properly protected;

4) Any other checks specified or recommended by the pump manufacturer/supplier.

5) Ensure that equipment operates with minimum vibration and noise within limits specified by the manufacturer and/or the Technical Schedules.

Commissioning

(i) Testing and commissioning shall be carried out to clearly demonstrate that the installed pump(s) meet the specified duty and performance requirement over the complete range of operating conditions.



(ii) Should testing show the performance to be less than specified, then all necessary changes shall be made to the equipment and installation for the performance criteria to be satisfied.

Compressed Air Systems

General

(i) This section describes the minimum requirements for the design, supply, delivery and testing of compressed air systems and appurtenances for both instrument air and process air applications.

(ii) The type of compressors as specified in the Particular Specifications shall be provided. The general requirements for the compressed air systems shall include but not necessary be limited to the following:

1) Supply and delivery of all necessary units of single stage oil-injected rotary screw air compressors with built-in control panels [with auto start/stop push-buttons, load/unload features, indicators (start/stop/trip), alarms, labels], pressure regulators, filters, ventilation fans, lubrication oil system, coolers, gauges, control devices, moisture filters/separators, pipes, bends, valves, flanges, fittings and all other associated auxiliaries.

2) Supply and delivery of all required air refrigerant dryers with built-in panels [with auto start/stop push-buttons, load/unload features, auto cut-in/cut-out, indicators (start/stop/trip)], labels, heat exchangers, compressors, condensers, built-in ventilation fans, lubricating oil system, moisture filters/separators, control devices, pipes and fittings, valves and all other associated auxiliaries.

3) Supply and delivery of all required Pre-Filter c/w auto-drain system, push-fit design of filter elements, electronic level sensor auto-drain, pipes, bends, valves, flanges, fittings and all other associated auxiliaries.

4) Supply and delivery of all required After-Filter or Oil Removal Filter with auto-drain system, push-fit design of filter elements, electronic level sensor auto-drain, pipes, bends, valves, flanges, fittings and all other associated auxiliaries.

5) Supply and delivery of all required stationary air flow meters with digital display, fittings, flanges and all the necessary associated auxiliaries. The three (3) flow meters are to be installed at the discharge of each of the existing air receivers.

6) Supply and delivery of all required compressed air pipes at least SS304 material with pipe fittings, control devices, valves, etc to connect the air compressors (new and existing) to the air receivers; from air receivers to the Pre-Filter units, air refrigerant dryer units, After-Filter units; and thereafter to individual downstream devices. The connection shall include all necessary equipment as well as issuance of certificate of fitness by MOM WSH for the pressurized vessels of the air compressors, refrigerant dryers and air receivers.



7) Supply and delivery of suitably rated power, control and signal cables, trays, conduits, couplings, fittings, supports, electrical protection equipment/systems and other accessories for safe and complete electrical as well as instrumentation and control system. The Contractor shall lay the power and earth cable to connect the equipment to the distribution board; and the control/signal cables from the equipment to the PLC, SCADA and Server units.

8) Link relevant signals from the air compressors, new refrigerant dryers and air flow meters to the designated remote control panel to allow air compressor system to function as specified. Link relevant signals from the new air compressors, new refrigerant dryers and new air flow meters to the designated remote control panel to allow air compressor system to function as specified.

9) Install, test and commission items (a) to (h) mentioned above and for the whole system.

10) Supply and deliver the following spares for the new air compressors:

• Pressure relief valves (2 units) • Oil separator kits (2 units) • Air filter kits (2 units) • Oil filter kits (2 units) • Servicing and maintenance kits (4 sets)

11) Supply and deliver the following spares for refrigerant dryers:

• Electronic auto-drain (2 units) • Servicing and maintenance kits (4 sets)

12) Supply and deliver the following spares for each pre-filters and after-filters

• Servicing and maintenance kits for pre-filters (2 sets) • Servicing and maintenance kits for after-filters (2 sets)

13) Supply and deliver the following spares for each pre-filters and after-filters

• Servicing and maintenance kits for pre-filters (2 sets) • Servicing and maintenance kits for after-filters (2 sets)

14) Quarterly servicing of the air compressors, refrigerant dryers, pre-filters, after filters, air flow meters, compressed air piping system (including pipe fittings, valves, bends, flanges, etc), electrical and instrumentation systems, etc. during the Defects Liability Period.

15) Engagement of Required Personnel e.g. Project Supervisor; LEW; Welders; Pipe Repairmen; Scaffold Erectors/Inspectors; Lifting Supervisors; Specialist for Air Compressor and Air Refrigerant Dryer and Compressed Air Systems;

SCADA Programmer/Specialist; Test Personnel, etc, for the endorsement of proper installation of equipment and system under this contract.

Submission of Documents during Tender Stage

The Tenderer shall also submit the following documents for the purpose of evaluation:



(i) Technical literatures, brochures and specifications of the proposed air compressors, refrigerant dryers and all other equipment for this contract.

(ii) Schematic layouts and P&ID diagrams of the proposed equipment and associated auxiliaries to be installed. These schematic layout and P&ID diagrams shall include all the proposed equipment and associated auxiliaries, labels, pipe and cable routes, etc, for the purpose of evaluation.

(iii) Letter(s) of endorsement from the manufacturer(s) that the proposed refrigerant dryer are sized correctly to take the loads from the air compressor.

Mechanical Works for Air Compressors

(i) General

Below are the requirements for each required compressor at Kranji NEWater Factory expansion works:

Standards BS: ISO 1217

Quantity: (refer to Particular Specifications)

Type: Single-stage rotary screw compressor

Features: Auto cut-in/cut-out with max. 6 starts/stops per minute

Free Air Delivery (min.): (to Contractor’s design)

Max. operating pressure: (to Contractor’s design)

Motor power supply: 450V / 3 phase / 50Hz

Min. power rating: (by Manufaacturer)

In addition to the above table, the new air compressor unit with any or combination of, but not limited to, the following components:

1) Air intake filters

2) Silencers

3) Regulating and automatic unloading system

4) Integrated After-coolers

5) Automatic condensate drain pipes and valves

6) Check valves and isolation valves (inlet and outlet)

7) Pressure regulators and pressure gauges

8) Ventilation fans

9) Dryers

10) After Coolers

11) Air receiver tanks

The air compressors shall have the integral panel with any or combination of, but not limited to, the following features:



1) Starters (preferably Star-Delta)

2) On-line/Off-line control with automatic start/stop push button both at local and at SCADA

3) Fault indicators and alarm lamps

4) Power Supply / Start / Stop / Fault indicator lamps

5) Motor overload relay indicator lamps

6) Intake filter servicing indicator lamps

7) Temperature indicator lamps

8) Lubricating oil level

9) Hour meter indicating total running time

(ii) Design and Construction

The air compressor complete with the associated equipment shall be easy to operate and maintain. Preference will be given to the following:

1) Low maintenance costs

2) Ease of operation and overhaul

3) Good local back-up facilities from the supplier

4) Reliable

5) Energy efficient

6) ISO 9000 certified

Adequately sized filtering device shall be installed at the inlet of the new air compressors to prevent the entry of foreign objects into the unit.

The air compressor shall be designed with continuous operation with maximum of six (6) automatic starts/stops per minute for the rated FAD and pressure.

The air-ends of the air compressors shall be oil-lubricated. The oil/air separator of the air compressors shall last for at least 4,000 hours after successful commissioning, otherwise, the Contractor shall be responsible for replacing the oil/air separator and such materials and labor cost in doing so shall be borne by the Contractor.

The compressed air shall be cooled by the After-coolers before being discharged out of the compressors.

(iii) Sound Enclosure

The new air compressors shall have built-in sound-proof feature with complete access for maintenance purposes via easily removable door(s).

The Contractor shall take note of the actual space available at the site and offer suitably-sized air compressors with silencing enclosure to fit into the existing available space.

The noise level of the air compressor during operation shall be less than 80 dB (A) at a circumference distance of one (1) meter from air compressors enclosure, with none of the equipment running in the vicinity.



(iv) Safety Features

The Contractor shall furnish concise description of the safety features incorporated in the air compressor and its associated equipment offered upon submission of tender.

(v) Pre-Filter and After (Oil Removal) Filter

The Contractor shall supply, deliver, install, test and commission two (2) units each of the following: 1) (a) Pre-Filter; and,

2) (b) After (Oil Removal) Filter.

Each of these shall come with auto-drain, push-fit design of filter elements, electronic level sensor auto-drain, pipes, bends, valves, flanges, fittings and all other associated auxiliaries.

These Pre-Filter and After (Oil Removal) Filter shall complement the air compressors, air refrigerant dryers and receiver tanks. There shall not be any tie rods to hamper the replacing any of the used elements.

(vi) Air Refrigerant Dryer

1) General

The Contractor shall supply, deliver and install two (2) units of Air Refrigerant Dryers at Kranji NEWater Factory.

The refrigerant dryers and all its electrical ancillaries shall be designed for 50 hertz operation.

They shall be stand-alone functional units and installed along with the new Pre-Filters and After-Filters (for Oil Removal) plus the new and existing air compressors.

The refrigerant dryers shall be complete with any or combination of, but not limited to, the following main components:

• Refrigerant compressors c/w motors • Refrigerant condensers • Motor driven cooling fans • Heat exchangers • Water separators and automatic condensate drain valves • Discharge check valves and isolation valves • Pressure gauges • Temperature gauges • Ventilation fans

Each of the refrigerant dryers shall have an integral panel with any or combination of, but not limited to, the following features. • Motor overload relays and shutdown indicator lamps • Hour meters indicating total running time • Power Supply / Start / Stop / Fault indicator lamps



• Fault indicators and alarm lamps • Temperature indicator lamps • Lubricating oil level (if any) • Hour meter indicating total running time

2) Design & Construction

The refrigerant dryers shall be integral and automatic functional units, complete with associated equipment which shall be easy to operate and maintain. Preference will be given to the following:

• Low maintenance costs • Ease of operation and overhaul • Good local back-up facilities from the supplier • Reliable • Energy efficient • ISO 9000 certified.

3) Performance Requirements

The refrigerant dryers shall be the air-cooled type, using the surrounding ambient air as the cooling media. Each refrigerant dryer shall be designed in accordance with DIN/ISO 7183 Standards and must be able to withstand the load from each new air compressors of minimum 2,180 liters/min at 10 bar (gauge). The refrigerant dryer must be able to withstand the maximum compressed air inlet temperature of 65oC and maximum compressed air inlet operating pressure of 50 bar (gauge). Though supplied and installed as a separate unit, each new refrigerant dryer shall operate as part of the new air compressor, continuously processing the outlet air from the air compressor. The motor for the dryer shall not exceed 3 kilowatts while the cooling fan shall not exceed 0.5 kilowatts. The rotating equipment in the dryer shall be oil-lubricated.

4) Sound Enclosure

The refrigerant dryer shall be housed within an acoustically treated sound enclosure with complete access for maintenance purposes via easily removable doors. The Contractor shall take note of the actual space available at the sites and offer a suitably sized refrigerant dryer unit with silencing enclosure to fit into the existing available space. The noise level of the refrigerant dryer during operation shall be less than 80 dBA at a circumference distance of one meter from the air dryer enclosure, with none of the equipment running in the vicinity.



5) Safety Features

The Contractor shall furnish concise description of the safety features incorporated in the refrigerant dryer and its associated equipment offered upon submission of tender.

6) Air Flow Meters

• General The Contractor shall supply, deliver, install, site acceptance test and commission all required air flow meters. The air flow meters shall be suitable for in-line mounting or orifice type working by differential pressure principle. They shall be designed to operate accurately at the maximum rated pressure of the air compressors. Flanged end connections pressure transducer with flow rate indication type of air flow meters is acceptable if the operating pressure is deem too high for the orifice type of air flow measuring device.

• Construction and Materials

The flow-meters to be supplied shall have a single structure, which can be easily dismantled without any special tools required. The flow meters shall be the in-line flange mounting type, which can be installed directly into the pipeline and be able to measure instantaneous flow rate of air with high accuracy. The mounting fittings and discharge pipe-works for the flow meter shall be similar as the compressor discharge. The flow meters and pipe-works shall be suitable for temperatures and pressures of the discharge air of the respective compressors. Details of mounting method shall be submitted for approval. The materials for the various parts of the flow meter are as follows: − Flange & Orifice : Stainless steel grade 316 − Bolts & Nuts : Stainless steel grade 304 or better − Taper tube : Borosilicate glass − Float : Stainless steel grade 316 − Packing : EPDM − Accuracy

The accuracy of the flow meters shall be ± 2% of the full scale. − Maximum Temperature

The flow meters shall be able to operate at the maximum temperature of the discharge

− Pressure and Flow Rating



The pressure rating of the flow meters shall range between 0-16 bar (g). The maximum flow range of the flow meters shall be sized by the Contractor to suit the maximum flow rate of each air compressor offered. The same size flow meter shall also be installed for the existing air compressor.

− By-Pass, Fittings and Accessories Each flow meter shall be equipped with isolation stainless steel full-bore ball valves upstream and downstream of it. A by-pass line complete with stainless steel full-bore ball valves shall be installed across the above assembly. The valves shall be of the same diameter as the pipeline. A stainless steel protective cover shall be provided to guard the borosilicate sight glass from external damage. Details of the protective cover shall be submitted for approval.

(vii) Testing and Commissioining

The Contractor shall perform the following commissioning tests:

1) Leakage test on the compressed air pipes using ultrasonic leak detection device to be provided by the Contractor

2) Performance test of the air compressors to ensure the proposed aircompressors are able to deliver the rated capacities at the rated pressures.

3) Performance test of the refrigerant dryers to ensure the proposed refrigerant dryers are sized correctly to take the load from the air compressors.

4) Start-stop operation both at local and remotely from SCADA. The Contractor shall test for the air compressors and refrigerant dryers, each able to operate within the maximum automatic six (6) starts/stops per minute.

5) Noise level test

6) Any other tests deemed required

The complete compressed air system shall be allowed to run smoothly for a minimum duration of seven (7) continuous days before it is considered as successfully commissioned and handed-over to the Board.

(viii) Other Requirements

1) Engagement of Required Personnel

The Contractor shall engage qualified persons for the endorsement of proper installation and successful testing and commissioning of equipment and system under this contract e.g. Project Supervisor, LEW, Welders, Pipe Repairmen, Scaffold Erectors/Inspectors, Lifting Supervisors, Specialist for Air Compressor, Refrigerant Dryer & Compressed Air Systems, Test Personnel, etc. The relevant specialized person shall be responsible for the issuing the test certificate of the air compressors registered with MOM WSH.



2) Spares

• Air Compressors The Contractor shall supply and deliver the following spares for the air compressors: − Pressure relief valves (2 units) − Oil separator kits (2 units) − Air filter kits (2 units) − Oil filter kits (2 units) − Servicing and maintenance kits (4 sets)

• Refrigerant Dryers

The Contractor shall supply and deliver the following spares for the refrigerant dryers: − Electronic auto-drain (2 units) − Servicing and maintenance kits (4 sets)

• Pre-Filters and After-Filters

The Contractor shall supply and deliver the following spares for the Pre-Filters and After-Filters: − Servicing and maintenance kits for pre-filters (2 sets) − Servicing and maintenance kits for after-filters (2 sets)

(ix) Training

The Contractor shall conduct training (operation, maintenance as well as safety, health and environmental aspects) of the complete compressed air system, equipment supplied and installed, operating via SCADA and local, etc for the Board’s officers.

A copy of the instruction notes shall also be submitted for vetting. All the Board's officers who attend shall be individually given a copy of the notes.

On the safety aspects of the training, the Contractor shall include the risks involved in handling the air compressors, refrigerant dryers and all associated auxiliaries including how to handle over-pressure, over-temperature, leaks in the compressed air pipes and devices, how to conduct leak detection using ultrasonic device, etc.

Blower Air Sytems

General

(i) Scope

This section covers the furnishing of electric motor driven, rotary, positive displacement blower packages to be sized, supplied, installed, tested and commissioned as indicated on the drawings and as required.



Each blower package shall be a factory or shop fabricated skid and shall include blower, motor, inlet silencer, discharge silencer, belts, sheaves, belt guard, flexible connections, safety valve, discharge check valve, instrumentation, controls, and vibration isolators mounted within an acoustical enclosure. Each blower package shall be complete with all spare parts, accessories and appurtenances indicated on the drawings, specified herein, or otherwise needed for proper operation.

Piping, pipe supports, valves, and accessories that are not an integral part of the equipment or specified herein are covered in other sections.

1) Coordination

Equipment furnished under this section shall be fabricated and assembled in full conformity with the specified design intent able to serve the full purposes of process operational requirements.

Where two or more units of the same class of equipment are required, they shall be the products of a single manufacturer; however, all the component parts of the system need not be the products of one manufacturer.

The blower units shall be a current standard product of the blower manufacturer and shall be a fully shop assembled package. All accessory items, including the acoustic enclosure, shall be furnished by the blower packager.

For general construction contracts and air scouring applications, the Contractor shall be responsible for coordinating the blowers with the equipment specified in the filter equipment and media section. The Contractor shall be responsible for any changes required in the blower design resulting from changes in the filter design, including air flow, or pressure losses pertaining to issue of air from submerged openings of piping systems, underdrains, or orifices.

2) Governing Standards

Except as modified or supplemented herein, all works covered by this section shall be performed in accordance with all applicable municipal codes and ordinances, laws, and regulations which pertain to such work. In case of a conflict between these specifications and any state law or local ordinance, the latter shall govern.

3) Nameplates

Each blower shall be provided with a nameplate for the equipment designation as required. Letters shall be not less than 25 mm high and shall be black baked enamel on plate material as required.

The location of nameplates and the method of attachment shall be acceptable to the Client.

4) Lubrication

Equipment which require attention no more frequently than weekly during continuous operation shall be adequately lubricated.



Lubrication systems shall not require attention during startup or shutdown and shall not waste lubricants.

Lubricants shall be provided in sufficient quantities to fill all lubricant reservoirs and to replace all consumption during testing, startup, and operation prior to acceptance of equipment.

Unless otherwise specified or permitted the use of synthetic lubricants will not be acceptable.

5) Abbreviations

Reference to standards and organizations in the Specifications shall be by the following designations:

AFBMA Antifriction Bearing Manufacturers Association AGMA American Gear Manufacturers Association AISC American Institute of Steel Construction AISI American Iron and Steel Institute ANSI American National Standards Institute ASME American Society of Mechanical Engineers ASTM American Society for Testing and Materials AWS American Welding Society IEEE Institute of Electrical and Electronics Engineers NEC National Electrical Code IEC International Electrotechnical Commission NPT National Pipe Thread UL Underwriters' Laboratories

(ii) Submittals

1) Drawings and Data

Complete assembly and installation drawings, wiring and schematic diagrams, together with detailed specifications and data covering materials used, parts, devices and other accessories forming a part of the equipment furnished, shall be submitted in accordance with the submittals section.

Device tag numbers indicated on the contract drawings shall be referenced on the wiring and schematic diagrams where applicable.

The data and specifications for each unit shall include, but not be limited to the following:

2) Letter of compliance from the blower manufacturer confirming blower package is fully shop assembled and will meet the performance requirements specified herein.

3) Dimensional drawings showing overall package dimensions, connection locations, elevation levels and sizes.

4) Package weight.

5) Maximum allowable forces and moments on package inlet and discharge flanges.

6) Net weight of heaviest single component requiring removal for maintenance.

7) Anchor bolt details and footprint drawings showing exact bolting locations.



8) Maximum free field noise level at 1 m.

9) Allowable side load on the blower shaft.

10) Side load imposed on the blower shaft by the drive system.

11) Blowers information as follows:

− Name of manufacturer.

− Type and model.

− Full rotative speed at rated condition.

− Blower design maximum rotative speed.

− Critical speed of the rotor.

− Type of bearings, AFBMA L10 life rating, and lubrication.

− Connection sizes.

− Maximum air temperature at discharge flange.

− Net weight of blower.

− Overall dimensions.

− Complete performance curves or tables showing discharge pressure versus capacity and speed, blower and overall efficiency, and bhp at minimum and maximum ambient air temperatures and at standard conditions.

− Blower displacement per revolution

− Shop painting data.

12) Control information as follows:

− Blower control panel layout including interior and exterior views.

− Accessory device data including catalog cut sheets on all control components.

− Wiring diagram.

13) Accessories information as follows:

− Name of manufacturer.

− Equipment data indicating overall dimensions, connection sizes, weights and materials of construction, pressure losses, efficiencies, and noise attenuation as applicable.

14) Certified Shop Test Reports



− Performance curves.

− Sample calculations.

15) Operation and Maintenance Manuals

When required, adequate operation and maintenance information shall be supplied. Operation and maintenance manuals shall be submitted in accordance with the submittals section.

(iii) Delivery, Storage, and Handling

Shipping shall be in accordance with the shipping section. Handling and storage shall be in accordance with the handling and storage section.

(iv) Spare Parts

Spare parts shall be provided as required.

Spare parts shall be suitably packaged.

Spare parts shall be delivered to OWNER as directed.

Products

(i) Service Conditions

All equipment provided under this section shall be suitable for the intended service conditions.

Operation of the units shall be as required.

(ii) Materials

Casing and Impellers Cast iron or ductile iron.

Shafts High carbon steel or ductile iron; turned, ground and polished.

Timing Gears Alloy steel.

Bearings Antifriction, oil lubricated, AFBMA rated L10 for 80,000 hours continuous operation.

Base Fabricated steel

(iii) Construction

1) Casings

Casings shall be designed to withstand at least twice the maximum discharge pressure and shall be reinforced with integrally cast ribs. Each casing shall be provided with tapped and plugged openings for casing and bearing drains, gauges, relief valves and fittings for properly adding bearing and gear lubricant.

2) Impellers

Impellers shall be reinforced by internal ribs and shall have all outside surfaces machined. Each impeller shall be statically and dynamically balanced. Impellers shall be arranged for vertical air flow through the units unless otherwise indicated.



3) Shafts

Shafts shall be cast integrally with the impeller or shall pass completely through the impeller. Stub shafts will not be acceptable. Impellers shall be securely attached to through shafts.

4) Timing Gears

Timing gears shall be enclosed in oiltight housings and shall be splash or pressure lubricated.

5) Belts and Sheaves

All belts and blower and motor sheaves required for the blower shall be furnished. Belts and sheaves shall be of the heavy-duty "V" type with a horsepower rating of at least 1.4 times the motor nameplate horsepower. Belts shall be matched sets.

6) Base Frame

7) A full length, common base shall be provided for each blower package.

The base frames shall be constructed of cast iron or heavy steel plate and structural members and shall be designed for no measurable deflection with the equipment mounted thereon and the base frame supported from the floor. Each base shall be designed so that all equipment bolted to it can be removed without access to the underside, and for ease of cleaning. Structural stiffeners shall be located under the equipment at the equipment anchor points. A drip lip will not be required. The base shall be suitable for direct attachment to the foundation. Complete support of the inlet and discharge silencers, the blower control panel and the acoustic enclosure shall be from the base frame. The blower supplier shall provide and install silencer supports for each blower package. The intake silencer shall be supported horizontally above the blower and the discharge silencer shall be supported horizontally below the blower.

8) Silencers

Each blower shall be furnished with a silencer in the suction and discharge piping as indicated on the drawings. Silencers shall be as recommended by the manufacturer.

9) Acoustical Enclosure

The acoustic enclosure shall be a self-supporting structure housing the blower, motor drive, and intake and discharge silencers and mounted on the package skid base. The enclosure shall be constructed of panels consisting of noise dampening material sandwiched between two metal sheets as required. The enclosure shall be provided with removable panels or hinged sections to allow routine blower maintenance. The maximum weight required to be lifted for removal/opening the access openings shall not exceed 23 kg.



All bracing and reinforcing members shall be integral to the enclosure. Blower oil drain piping shall be piped to outside of enclosure and terminated with a threaded pipe cap. Air piping shall be piped to outside of the enclosure and terminate with a pipe flange. The flanges shall be BS EN1092 of the appropriate pressure rating and drilling and shall extend not less than 100 mm outside of the enclosure for flange bolt removal.

10) An internal ventilating system shall be provided for the enclosure. The ventilation system shall utilize a 24 volt dc rated electric motor driven ventilating fan to draw ambient air into the enclosure for cooling the enclosed equipment prior to exhausting the air outside of the enclosure. Air inlet and exhaust openings shall have noise abatement features that meet the maximum noise level specified when the ventilating system and blower are operating simultaneously. The ventilating fan shall be powered and controlled through the blower control panel. When installed outdoors, the ventilation inlet and exhaust openings shall be designed to prevent rain/snow penetration during operation at the maximum wind speeds specified.

11) Anchor Bolts

Anchor bolts and nuts shall be furnished as required for each item of equipment. Anchor bolts, together with templates or setting drawings, shall be delivered sufficiently early to permit setting the anchor bolts when the structural concrete is placed. Two nuts and a washer shall be furnished with each anchor bolt.

The bolts shall be at least 12.5 mm in diameter.

Materials of Construction and grades for Anchor Bolts and Nuts shall be as follows:

Carbon Steel ASTM A307 or ASTM A36

AISI Type 304, 305, 384, 304L Bolts ASTM F593, Alloy Group 1; Nuts ASTM F594, Alloy Group 1

AISI Type 316, 316L Stainless Steel Bolts ASTM F593, Alloy Group 2; Nuts ASTM F594, Alloy Group 2

Galvanized Steel bolts and nuts hot-dip galvanized, ASTM A153 and

A385

Flat Washers ANSI B18.22.1; of the same material as the bolts and nuts.

(iv) Accessories

1) Special Tools and Accessories

Equipment requiring periodic repair and adjustment shall be furnished complete with all special tools, instruments, and accessories needed for proper maintenance.



Equipment requiring special devices for lifting or handling shall be furnished complete with those devices.

2) Intake Air Filters

Where required, intake air filters shall be provided as indicated on the drawings.

Each filter shall be cartridge type of all-welded steel construction with prime painted exterior, replaceable dry polyester filter element, and flanged outlet connection with diameter and drilling conforming to BS EN1092 10 Bar .

Filters shall be suitable for continuous weather exposure in exterior locations.

The intake filter shall be sized for a maximum filter housing face velocity of 2 m/s and shall connect to the suction piping without reducers.

3) Blowoff Silencers

Any requirement for blowing off and the blowoff silencer(s) shall be based on Contractor’s design.

4) Vibration Isolator Base Pads

Vibration isolator base pads shall be provided for each blower as recommended by the manufacturer.

5) Valves.

• Safety Valves Each blower shall be provided with a safety valve as recommended by the blower manufacturer. The safety valves shall be capable of protecting the blowers from damage due to operation with a closed discharge valve. For valves smaller than 50 mm, valves shall be spring loaded type. For valves 50 mm and larger, the safety valves shall be weighted type, anodized aluminum. Weights shall be chrome zinc plated and provided in 3.5 kPa increments. The valves shall be suitable for temperature up to 149°C. Set points shall be at least 7 kPa above the rated blower discharge pressure unless otherwise indicated.

• Check Valves An air check valve shall be installed in the discharge piping from each blower downstream of the discharge silencer inside the acoustic enclosure as indicated on the drawings. Check valves shall be provided with flanged ends or shall be suitable for installation between pipe flanges. Check valves shall be suitable for use with rotary positive displacement blowers and for operation at all temperatures between -18°C and 149°C.

• Pressure Gauges



A pressure gauge shall be furnished for monitoring pressure in the discharge piping of each blower at the location indicated on the drawings. The pressure gauge shall be mounted on the blower control panel. The sensing tubing installation shall not require disassembly for normal maintenance of the blower, motor or V-belts. Pressure gauges shall be of the indicating dial type with C-type phosphor bronze bourdon tube, stainless steel rotary-geared movement, phenolic open front turret case, adjustable pointer, stainless steel or phenolic ring, and acrylic plastic or shatterproof glass window. All gauges shall be ANSI Accuracy Grade A. Gauges shall be liquid filled, and sealed to prevent leakage. The dial shall be 112 mm size with white background and black markings and shall have metric indication. The metric units of measurement shall be kilopascals. The range for each gauge shall be as needed for pointer travel to be not less than 200 degrees or more than 270 degrees. Gauges shall be provided with a pressure snubber. Each snubber shall be of the size and pressure range compatible with the gauge served. All gauges shall be provided with 15 mm (1/2 inch) NPT connections. Each gauge shall be provided with a ball type shutoff valve installed at the blower discharge piping connection.

• Pressure Switches A pressure switch shall be furnished and installed in the discharge piping of each blower and furnished for installation across each intake filter as indicated on the drawings. Each switch in the blower discharge piping shall have an adjustable range of 0 to 103 kPa gauge and shall be set lower than the relief valve setting. Each switch across the intake filters shall have an adjustable range from 0 to 250 mm water column vacuum. Each pressure switch shall be field adjustable and shall have a trip point repeatability of better than 1 percent of actual pressure. Each switch shall have one normally open and one normally closed contact rated 10 amps at 24 volt dc. Each switch shall be wired to the blower control panel and shall shut down the blower on high discharge pressure or high pressure drop across the filter.



Each switch shall have a weatherproof IP56 housing.

• Draft Gauges When required, a draft gauge having a range from 0 to 250 mm water column shall be furnished for installation across each intake filter. The gauge shall have a minimum 87 mm dial, pressure taps, fittings for 6 mm metal tubing, vent valves, mounting brackets, and an adjustable signal flag.

• Thermometers A thermometer shall be provided for monitoring of temperature in the discharge piping at the location indicated on the drawings. The thermometer shall be mounted on the blower control panel. The capillary routing shall not require disassembly for normal maintenance of the blower, motor or V-belts. Thermometers shall be of the remote reading gas actuated dial type. Thermometers shall have a minimum dial size of 112 mm, an adjustable pointer, shall be accurate within 1 percent of full scale. Thermometers shall have both Fahrenheit and Celsius indication. Thermometers shall be furnished complete with a uniformly graduated dial indicator, armored capillary tube, bulb or temperature sensor, and thermowell. Thermometer ranges shall be such that the normal operating reading will be near the midpoint of the range. The units of measurement shall be indicated on the dial face. Spare capillary length shall be neatly coiled and tied.

• Temperature Switches Temperature switches shall be remote bulb type with one normally open and one normally closed contact rated 10 amps at 24 volt dc. Temperature switches shall have IP56 housings, stainless steel thermal well assemblies, and armored capillaries. Capillary length shall be sufficient for convenient mounting. Each temperature switch shall be wired to the blower control panel and shall shut down the corresponding blower on high discharge air temperature.

• Flexible Connections

An elastomeric, flanged, arched type flexible connection shall be provided in the suction and discharge piping adjacent to each blower as specified herein and indicated on the drawings.



Each flexible connection shall be sized to allow piping movement without exceeding the blower manufacturer's force allowance at the blower flange. The number of arches shall be as specified herein or as needed to meet the specified spring rates and movement capabilities. The inlet connection shall be suitable for 50 kPa vacuum service and the discharge connection shall be suitable for a pressure of 105 kPa gauge.

(v) Balance

All rotating parts shall be accurately machined and shall be in as nearly perfect rotational balance as practicable. Excessive vibrations shall be sufficient cause for rejection of the equipment. The mass of the unit and its distribution shall be such that resonance at normal operating speeds is avoided. In any case, the maximum unfiltered vibration velocity, as measured at any point on the machine, shall be as required. Vibration limits shall be as recommended by the manufacturer in accordance to BS4999-142.

At any operating speed, the ratio of rotative speed to the critical speed of a unit or its components shall be less than 0.8.

(vi) Drive Units

Each blower shall be driven by an electric motor through a belt drive as required. Drive units shall be designed for 24 hour continuous service.

1) V-Belt Drives

Each V-belt drive shall include a sliding base or other suitable tension adjustment. V-belt drives shall have a service factor of at least 1.6 times the motor nameplate kW of the drive motor.

2) Safety Guards

All belt drives, couplings, and other moving or rotating parts shall be covered on all sides by a safety guard. Safety guards shall be fabricated from 1.6 mm thick or thicker galvanized or aluminum-clad sheet steel or from 12 mm mesh galvanized expanded metal. Each guard shall be designed for easy installation and removal. All necessary supports and accessories shall be provided for each guard. Supports and accessories, including bolts, shall be galvanized.

3) Electric Motors

Motors used with adjustable frequency drives shall be rated for inverter service. The maximum brake horsepower shall be less than the motor nameplate rating by 5 percent or by the amount of the anticipated belt losses, whichever is greater.

(vii) Controls



1) Blower Motor Starters

Blower motor starters will be provided as specified under the electrical section. Motor starters will provide to the blower control panel one normally open dry motor run contact. The contact will close when the blower motor is started and will open when the blower motor is stopped.

2) Blower Control Panel

Each blower shall be furnished with a blower control panel. The blower control panel shall be furnished with all gauges, relays, pilot devices, indicators, etc., required to monitor and shutdown its respective blower for the following conditions.

High discharge air temperature, high discharge pressure, and high differential pressure across intake filter. In addition, the blower control panel shall shutdown its respective blower for motor and blower vibration as required.

The control panel shall be mounted separate from the blower package, and outside of the acoustic enclosure to prevent vibration from affecting panel mounted components.

All components installed in or on the panel shall be rated for the control power supply as required. If voltages other than the specified control power supply is required, the panel supplier shall furnish the required control power transformers.

The control panel shall be furnished with a white control power on indicating light.

The control panel shall be furnished with amber indicating lights for blower motor vibration warning, and/or blower vibration warning as required. The control panel shall be furnished with red alarm indicating lights for blower motor vibration shutdown, and/or blower vibration shutdown as required.

The control panel shall be furnished with red indicating alarm lights for high discharge air temperature, high discharge pressure, and high differential pressure across intake filter.

For all conditions above requiring red indicating lights control relays shall be furnished in the panel with normally open volt-free contacts rated 5 amps at 240 volt ac for remote annunciation of the condition. In addition, all alarm conditions shall be combined in the panel to generate a common alarm. The common alarm relay shall be furnished with one normally open and one normally closed contact each rated 5 amps at 240 volt ac. The normally open contact shall be used for remote annunciation and the normally closed contact shall be wired to the respective blower starter or controller for shutdown purposes.

The panel shall be furnished with a manual alarm reset pushbutton and all alarm conditions shall require a manual reset before the alarm condition and contact is cleared.



The panel shall be furnished with a warning and alarm light test pushbutton that illuminates all panel mounted lights when pushed.

3) Panel Fabrication Requirements. The control panel furnished shall conform to the requirements of IEC standards. Panels shall be rated IP56 and shall be constructed from stainless steel.

All panel wiring shall be of the type normally furnished by the manufacturer with the following exceptions.

All power and control wiring for 240 volt circuits shall be stranded copper 2.5 mm2 minimum.

All power and control wiring shall have a 1.1kV insulation rating and a nominal maximum operating temperature of 90 degrees C.

All analog circuits shall be 1.5 mm2 minimum twisted shielded pair rated for at least 300 volts. Conductor insulation for power, control, and analog circuits shall have a moisture-resistant and flame-retardant covering.

All wiring shall be grouped or cabled and firmly supported inside the panel. Wiring shall be bundled in groups and bound with nylon cable ties or routed in Panduit or similar nonmetallic slotted ducts.

Ducts shall be readily accessible within the panel, with removable covers, and with space equal to at least 40 percent of the depth of the duct remaining available for future use after completion of installation and field wiring. Sufficient space shall be provided between cable groups or ducts and terminal blocks for easy installation or removal of cables.

The power entrance to each panel shall be provided with a surge protection device. Surge protectors shall be nominal 240 volts ac with a nominal clamping voltage of 300 volts. Surge protectors shall be of non-faulting and non-interrupting design, with a response time not to exceed 5 nanoseconds. Surge protectors shall be manufactured by Innovative Technology, Power Integrity Corporation, or Transtector.

Terminal blocks shall be suitable for 2.5 mm2 wire and shall be rated 30 amperes at not less than 300 volts. Terminal blocks shall be fabricated complete with marking strips, covers, and pressure connectors. Terminals shall be labeled to agree with the identification on the System Supplier's submittal drawings. A terminal shall be provided for each conductor of external circuits, plus one ground for each shielded cable. At least 25 percent spare terminals shall be provided. Not less than 200 mm of clearance shall be provided between the terminal strips and the base of vertical panels for conduit and wiring space.

Nameplates shall be provided on the face of each panel and on each individual control or pilot device. Panel nameplates shall be made of laminated phenolic material with engraved letters approximately 5 mm high extending through the black face into the white layer, and shall be secured firmly to the panel.

All control and pilot devices furnished shall be IP56 rated, heavy duty oiltight.

4) Panel Factory Test



Before shipment, the panels shall be electrically tested by the manufacturer.

5) Sequence of Operation

The blower sequence of operation shall be as indicated below: Startup Sequence:

− Energize blower motor.

Shutdown Sequence:

− De-energize blower motor.

(viii) Shop Painting

All steel and iron surfaces shall be protected by suitable coatings applied in the shop. Surfaces that will be inaccessible after assembly shall be protected for the life of the equipment. Coatings shall be suitable for the environment where the equipment is installed. Exposed surfaces shall be finished, thoroughly cleaned, and filled as necessary to provide a smooth, uniform base for painting. Electric motors, speed reducers, starters, and other self-contained or enclosed components shall be shop primed or finished with an oil-resistant enamel or universal type primer suitable for top coating in the field with a universal primer and aliphatic polyurethane system. Machined, polished, and nonferrous surfaces shall be coated with rust-preventive compound.

(ix) Shope Tests

1) Operational Test

Each blower shall be shop tested by the manufacturer for vibration and pressure developed and shall be checked for leaks, faulty components and controls.

2) Slip Test

A slip test shall be performed on each blower.

The test shall consist of an ASME PTC-9 slip test, with calculations correcting the results to field conditions, to ensure compliance with specifications.

3) Vibration Test



A vibration test shall be performed on each blower. When the vibration test indicates an overall vibration velocity greater than 11.5 mm per second, the manufacturer shall be responsible for performing and reviewing a frequency analysis.

The manufacturer shall make corrections as necessary, and confirm that the vibration velocity will not be detrimental to the equipment. An overall vibration velocity greater than 25 mm per second shall be sufficient cause for rejection of the equipment.

Defective equipment and controls disclosed by the tests shall be replaced and each unit placed in satisfactory operating condition before shipping.

A certified electronic copy of the test report complete with performance curves, data, and all calculations shall be submitted in accordance with the submittals section.

(x) Field Quality Control

1) Installation Check

When required, an experienced, competent, and authorized representative of the manufacturer shall visit the site of the Work and inspect, check, adjust if necessary, and approve the equipment installation. The representative shall be present when the equipment is placed in operation and shall revisit the job site as often as necessary until all trouble is corrected and the equipment installation and operation are satisfactory in the opinion of Client. The manufacturer's representative shall furnish a written report certifying that the equipment has been properly installed and lubricated; is in accurate alignment; is free from any undue stress imposed by connecting piping or anchor bolts; and has been operated under full load conditions and that it operated satisfactorily. The manufacturer's representative shall verify:

− Each blower discharge isolation valve is fully open. − Each check valve is properly installed. − Piping is installed such that excessive force is not being exerted on the

blower flanges. − No resonance vibration conditions are occurring within the blower

package.

All costs for these services shall be included in the contract price for the quantity of days and round trips to the site as required.



2) Field run test.

When required, each blower shall be mechanically checked for proper operation. Each alarm and safety shutdown shall be checked by artificially simulating an alarm condition. Defective equipment and controls disclosed by the tests shall be replaced or corrected, and the packages placed in satisfactory operating condition. The following items shall be measured, recorded, and submitted in a field test report: − Discharge pressure, each blower. − Discharge temperature, each blower. − Differential pressure across each intake filter unit. − Pressure and temperature at downstream end of piping system and at

any measurement taps provided. − Flow measurements at any flow meters provided. − Outdoor ambient temperature. − Indoor ambient temperature. − Barometric Pressure.

Test reports shall verify that the specified tests have been performed and shall state results.

(xi) Training

When required, the manufacturer's representative shall provide training for OWNER in proper operation and maintenance of the equipment. Such services shall be included in the contract price.

Process Pipework

Scope of Work

(i) The Scope of Works under this Contract for the Mechanical Works shall include but shall not be confined to the complete supply, installation, construction, testing and commissioning of the following items. The Contractor shall include all items and accessories and necessary design to provide a complete, operating and certified system irrespective of whether or not all items are specifically mentioned in the Specification or on the Drawings.

(ii) Pipework to be Supplied and Installed

1) The Contractor shall design, supply and install all pipework. The sizes, diameters and arrangement of the pipework within the pump station shall be designed to suit the pumping equipment.

(iii) Limits of Pipework

1) The pipework shall be constructed to the limits specified in the Particular Specifications for Interface Works. All pipes shall be finished at those limits with flanged ends unless specified otherwise.

(iv) Pumping Equipment



1) Pumping equipment shall generally include pumps, motors, instruments and all electrical and control wiring. For pumps and motors that are not close coupled, the supplied equipment shall include the pump and motor mounting frame and coupling. For submersible pumps, the supplied equipment shall include the discharge duck-foot bend, guide rails and lifting chains.

2) The Contractor shall install the pumping equipment and make inflow and outflow pipe connections, including hydrostatic testing, to the other pipework to be supplied and installed under this Contract. Installation of the pumping equipment shall include to the supply of all bolts, support brackets and other materials, equipment and labour necessary for fixing the equipment in place to withstand in service loads and vibrations. Installation of the pumping equipment shall be undertaken by appropriately experienced personnel fully in accordance with directions provided by the suppliers of the pumping equipment.

3) The Contractor shall be responsible for providing all electrical and instrumentation connections to the pumping equipment and commissioning of the equipment.

(v) Instrumentation Tappings

1) The Contractor shall provide tappings for all instruments, sampling points, etc in the pipelines in accordance with the P&ID drawings provided. Grade 316 stainless steel ball valves shall be provided where shown on the P&ID drawings.

2) The Contractor shall also allow for any addition tappings to suit the particular equipment or system installed. Tappings shall not be drilled direct to ABS or CPVC pipes and fittings, except where the sizes are within the pipe manufacturer’s recommendations. Tappings to ABS and CPVC pipe shall be made by solvent welding saddles or fitting.

(vi) Electromagnetic Flowmeters

1) Electromagnetic flowmeters to be located within the yard pipework and product delivery line pipework shall be supplied and installed by the Contractor.

2) The Contractor shall provide all flowmeters for this project.

Pipe Materials

(i) Material Types

1) The pipework to be incorporated into the works shall be in accordance with those types, levels and dimensions shown on the drawings. The pipework shall include but are not limited to the following material types:

• ABS • CPVC • HDPE • Stainless steel (SS)



(ii) ABS Pipes and Fittings

1) All Acrylonitrile Butadiene Styrene (ABS) pipes and fittings shall be manufactured to the following Australian standards:

• AS 3518 Part 1 ABS Pipes and Fittings for Pressure Applications: Pipes

• AS 3518 Part 2 ABS Pipes and Fittings for Pressure Applications: Fittings

• AS 3690 Installation of ABS Pipe Systems • AS 3879 Solvent Cement and Priming Fluids for

PVC (PVC-U and PVC-M) and ABS and ASA Pipes and Fittings

2) All ABS pipes, fittings and ABS solvent cement used for joining must be manufactured and supplied by the same manufacturer to ensure compatibility in dimensions and pipeline system.

3) All ABS pipes installed under this Contract shall have a pressure rating suitable for the process but not less than Class 10.

4) The Contractor shall engage only personnel familiar with the installation

procedures for the ABS piping systems for the installation works. Jointing techniques and materials shall be as recommended in the manufacturer’s handbook and standard specifications. A copy of the manual and standard specifications shall be provided to the S.O.

(iii) CPVC Pipes and Fittings

1) CPVC pipes, fittings and specials shall be of the spigot and socket type. All PVC and CPVC pipe and fittings are to be produced from compounds which conform to and are specified as ASTM D1784. Pressure rated (SDR series) PVC pipe is manufactured in strict compliance with ASTM D2241, ISO9002 Certified and National Sanitation Seal of Approval for drinking water

2) All the pipes and fittings shall be solvent cement welded to BS 4346. They shall be resistant to ultra-violet attack and shall be of an approved colour. Rubber jointing rings for spigot and socket shall conform to BS EN 681.

(iv) HDPE Pipes and Fittings

1) HDPE (High Density Polyethylene) pipe shall comply with AS 4130 (Int). All polyethylene pipes shall be high-density type 50 class 12 unless specified otherwise.

2) The HDPE pipe shall not be subject to bending to a radius tighter than 25 times the pipe outside diameter.

3) Hot bending shall not be permitted.

4) All fusion bonding processes shall be strictly in accordance with the manufacturer’s recommendations and procedures.

5) HDPE pipes and fittings are prone to surface damage if incorrectly handled or stored as well as being subject to degradation when exposed to sunlight.



6) All handling and storage shall be strictly in accordance with the manufacturer’s recommendations and procedures. No metal chains or slings shall be used.

7) All pipe laying shall be in accordance with manufacturer’s recommendations and installation procedures.

8) HDPE has a relatively high coefficient of linear expansion (Approx 0.18 mm/▪C). When laying the pipe sufficient allowance must be made for expansion and contraction.

(v) Stainless Steel Pipes and Fittings

1) The design and fabrication of pipework shall be carried out under this Contract. Stainless steel pipework shall be fabricated from Grade 316 L stainless steel.

2) The Contractor shall engage a qualified professional engineer experienced in the design and fabrication of stainless steel pipework to design the pipework. The pipework shall be designed for a maximum internal pressure to suit the specified design requirements and a minimum internal pressure equal to a full vacuum. Both of these pressure extremes may occur under transient pressure (water hammer) conditions.

3) Pipework sections shall be manufactured from fittings utilising Grade 316L stainless steel reducers, elbows and tees manufactured to ASTM A774 with dimensions conforming to ANSI B16.9.

4) The Contractor shall ensure that all welds meet all the requirements for welding of Austenitic Stainless Steel Tube and Pipe Systems in Sanitary Applications as specified by the American Welding Society AWS D18.1:1999. The Contractor shall arrange for the S.O. or a nominated representative to inspect and approve the welding work prior to acceptance.

5) All welding shall be full penetration and continuous, and all gaps shall be fully sealed. The completed work shall be free from distortions and true to dimensions. All connections shall be welded in a manner such that the finished connections are neat, smooth in appearance, and all sharp edges ground and all projections ground smooth suitable for provision of corrosion protection and aesthetic finishes.

6) After welding of stainless steel, welds and the adjacent plate shall be cleaned, pickled and passivated both internally and externally. Passivation shall be carried out in the fabricator's works. All welds in contact with water shall be ground and polished smooth to achieve a smooth surface free of pits and voids prior to passivating. After passivation, fabricated components shall have a clean, matt finish free from scale and discolouration caused by welding or heating.



7) Care shall be taken when handling the stainless steel before, during and after fabrication to prevent contamination with mild steel materials, dust, shavings, weld splatter 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.

Pipe Lining Materials

(i) Fusion-Bonded Medium Density Polyethylene Lining and Coating for Pipes and Pipe Fittings

1) Polyethylene used for lining and coating of the pipes and pipe fittings shall be fusion-bonded medium density polyethylene with a density of about 930 kg/m3. The lining shall have a thickness of at least 1.0 mm for all sizes of pipes and pipe fittings. For the materials to be used as coating on the external surface of pipes and pipe fittings, the minimum thickness shall be 1.8 mm for 150 mm, 300 mm and 500 mm diameter pipes, and 2.3 mm for 700 mm and 900 mm diameter pipes. The lining and coating materials shall have a continuous protection to the metal part of the pipes and pipe fittings without cracks.

2) The dielectric resistance of the polyethylene shall be about 200 kV/cm. The shock resistance of the polyethylene shall be more than 18 N-m. The polyethylene shall have an elongation of more than 300%. It shall have no effect subject to salt water spray test of 1000 hours and shall have the chemical resistance against chlorinated water, water solution of salts, acids and bases of pH 5 to pH 9.

3) In terms of head loss, the roughness coefficient (k) in the Colebrook-White formula for the polyethylene shall be less than 0.01 mm or alternatively the Hazen William coefficient in the Hazen William formula shall be 150 or higher.

(ii) Fusion-Bonded Epoxy Lining for Pipes and Pipe Fittings

1) Epoxy used for lining of the pipes and pipe fittings shall be fusion-bonded epoxy for the straight section of pipes. At the socket end of a pipe, the epoxy used for lining shall comprise fusion-bonded epoxy as first coat, and a second coat of epoxy if required by the manufacturer. The lining shall have a total thickness of at least 0.5 mm for all sizes of pipes and pipe fittings, and at least 0.3 mm for the socket. The outer portion of the spigot end in contact with NEWater may be coated with a first coat of zinc-rich paint follow with a second coat of epoxy of about 0.3 mm, to give a total thickness of 0.33 mm, in place of fusion-bonded epoxy if necessary. The finished epoxy lining shall have a continuous protection to the metal part of the pipes and pipe fittings without cracks.

2) The shock resistance of the epoxy shall be more than 11 N-m. The fusion-bonded epoxy shall have an elongation of more than 10%. It shall have no effect subject to salt water spray test of 1000 hours and shall have the chemical resistance against chlorinated water, water solution of salts, acids and bases of pH 5 to pH 9.



3) In terms of head loss, the roughness coefficient (k) in the Colebrook-White formula for the epoxy shall be less than 0.01 mm or alternatively the Hazen William coefficient in the Hazen William formula shall be 150 or higher.

(iii) 100% Solids Rigid Polyurethane Lining for Pipes and Pipe Fittings

1) Polyurethane used for lining of the pipes and pipe fittings shall be of 100% solids rigid polyurethane with a density of about 1600 kg/m3. The lining shall have a thickness of at least 1.0 mm for all sizes of pipes and pipe fittings, and at least 0.3 mm for the socket and the outer portion of the spigot end. It shall have a continuous protection to the metal part of the pipes and pipe fittings without cracks.

2) The dielectric resistance shall be about 200 kV/cm. The shock resistance of the polyurethane lining shall be more than 12 N-m. It shall have an elongation of more than 10%. The polyurethane shall have no effect subject to salt water spray test of 1000 hours. It shall have the chemical resistance against chlorinated water, water solution of salts, acids and bases of pH 5 to pH 9.

3) In terms of head loss, the roughness coefficient (k) in the Colebrook-White formula for the polyurethane shall be less than 0.01 mm or alternatively the Hazen William coefficient in the Hazen William formula shall be 150 or higher.

(iv) Pipe Joints

1) Flanged Joints

• All flanged joints shall be manufactured with full-machined faces in accordance with BS EN 1092 “Flange and Their Joints - Circular Flanges for Pipes, Valves, Fittings and Accessories, PN Designated”. Flanges shall be suitable to carry the hydrostatic working pressures set out herein and shall be drilled to suit the working pressures specified herein or to match the class of the adjoining flange, whichever is of the higher rating otherwise instructed by the S.O.

• Backing flanges to ABS stub flanges shall be manufactured from Grade 316L stainless steel.

• Flange Gaskets − Flange gaskets shall be manufactured from rubber insertion cloth

of not less than 3 mm thickness. The gasket material shall conform to the requirements of BS 6956-5: 1992.

• Bolts and Nuts − Bolts with hexagon heads and hexagon nuts shall be both

manufactured from Grade 316 stainless steel. Flat stainless steel washers shall be provided with each bolt and nut set. Bolts and nuts shall comply with the relevant sections of BS EN ISO 3506”.

− The nominal lengths of bolts for pipe flanges shall be equal to twice the thickness of the pipe flange plus twice the diameter of the bolt. The bolts shall be threaded for a length equal to twice the diameter of the bolt.



• Metal to Metal Faces − Where stainless steel surfaces come in contact with dissimilar

metals, including mild steel, the stainless steel surfaces shall be kept from direct contact with the metal by use of PTFE gaskets or high strength phenolic washers.

Process Pipework Design

(i) Development of Design Drawings

1) The tender document P&IDs show pipe, valve and instrument arrangements for the interconnecting process pipework between the pumping equipment process units and other pipework to be supplied and installed under this Contract. The actual sizes of the pipes, valves and fittings shall be determined by the Contractor after the award of the Contract. The Contractor shall provided to the S.O. drawings details dimensions the layouts and requirements of all piping, pumps and process equipment.

2) The Contractor shall prepare and submit copies of the layout drawings of the pipework, valves and fittings for each pump station within this Contract. The layout and design of the pipework shall facilitate its erection and the dismantling of any section for maintenance. The grading of the pipework shall ensure that air pockets cannot accumulate on the suctions of pumps and that air is released through air valves on the deliveries.

3) Shop drawings shall be submitted for all fabricated, pipework and fittings.

4) The cost of any amendments to the structures to accommodate the Contractor’s layout and design shall be deemed to have been included in the Contractor’s tender price.

(ii) Supported Pipework

1) All elevated pipework shall be securely supported and fixed using suitable purpose made brackets or hangers. The pipe supports shall comply with BS 3974 Parts I and II, MSS SP58, SP69 and SP89 and shall be of Grade 316 stainless steel. Hangers, supports or pipe racks shall be provided in each direction at each change in direction.

2) Insulation materials as specified herein shall be used at all interfaces with dissimilar materials.

(iii) Connecting Pipework

1) All pipes connected to pumps and values shall have flanged connections with dismantling joints.

(iv) Fittings

1) Flexible joints shall be of an approved type and manufacture. Tie bars shall be used to provide for continuity of restraining forces across tied dismantling joints.

Flushing and Testing Process Pipework

(i) General



1) The Contractor shall supply all materials, plant, labour and equipment for the flushing, testing and sterilisation (where necessary) of all process pipework. Flushing and testing shall be carried out to all pipelines constructed under this Contract prior to hydrostatic pressure testing.

2) Prior to hydraulic pressure testing of mains, the Contractor shall flush all mains and connections. The rate of filling the mains with water shall be such that the water velocity therein shall nowhere exceed 0.05 m/s. Flushing shall be done by scouring under pressure at all scours and drain points as directed by the S.O.

3) Upon repair of all breaks which occur during or after testing, the Contractor shall flush again that section of pipework as detailed above.

4) Where a pipeline ends without a valve at this Contract’s limit of works the Contractor shall seal off the end of the pipeline to allow for the pipeline to be hydrostatically tested as specified herein. Sealing off shall be achieved by the provision of blank flanges or end caps.

5) Pressure testing shall be undertaken as soon as possible after the solvent welded joints (as applicable) have had time to develop adequate strength. The temperature of the piping material shall not exceed 40oC during the test period. All tests shall be carried out under the supervision and in the presence of the S.O. or his representative

6) Care shall be taken to remove all air from mains under test when filling with test water. The rate of filling of the test section with water shall be such that the water velocity within the test section shall nowhere exceed 0.05 m/s.

7) Subsequent to filling and prior to the formal pressure test as detailed below, the water pressure shall be raised to a value equivalent to two-thirds of the pressure proposed for the hydrostatic test. This pressure shall be sustained for a period of 30 minutes or as directed by the S.O., sufficient to allow a thorough inspection of the section of pipeline under test for defects or failures. Any defects or failures that become evident shall be repaired in an approved manner by the Contractor at his own expense. Following repair, the water pressure shall be restored preceding the execution of the hydrostatic pressure test at the specified test pressure.

8) The hydrostatic pressure test shall be a constant pressure test unless otherwise specified. Valves within the test section shall remain open during pressure testing. The hydrostatic test pressure developed in the lowest section of the length of main or mains under test shall be 1.5 times the maximum working pressure of the pipeline or pump shut off whichever is greater.

9) After pressurising the length of pipework to the required pressure, the section under test shall be allowed to stand without make-up pressure and shall be deemed to have passed the test provided that:



• there is no failure of any, pipe, fitting, valve, joint or any other pipeline component or support; and

• there is no visible leakage of the test water after at least 30 min under pressure, or after the time necessary to inspect all joints.

10) Where water losses occur during the hydrostatic pressure test, the length of main or pipework under test shall be carefully examined for defects and such defects shall be repaired in an approved manner by the Contractor at his own expense. The specified filling and hydrostatic pressure testing procedures shall then be repeated. This process shall be repeated as necessary until such time as the length of main or mains under test has satisfied the test criteria for acceptance.

11) All hydrostatic testing shall be carried out by the Contractor at his own risk, and he shall provide all necessary labour and equipment for the satisfactory performance of the test or tests. This equipment shall remain the property of the Contractor.

12) All gauges or instruments used for tests shall be fully calibrated and certified by an approved testing laboratory.

Valves

General

(i) All valves of the same type (ie butterfly, globe valves, ball vales, non return valves etc) shall where possible be of the same manufacturer.

(ii) All flanged valves shall be supplied with flange drilled to BS EN 1092, PN designated, unless otherwise specified or instructed by S.O..

(iii) For the actuated valves, the actuator and the valve shall be supplied by a single responsible supplier for proper coordination of design, assembly, testing and installation works.

Butterfly Valves

(i) Butterfly valves shall be of the resilient seated wafer type or double flanged with replaceable elastomeric seats. Wafer type valve shall be fully lugged with threaded holes.

(ii) The butterfly valves shall generally comply with requirements of BS EN 593 or the applicable ISO standard. Manufacture shall be to ISO 9001. All valves shall be hydraulically tested as per ISO 5208 and test certificates shall be provided.

(iii) The shaft and disc shall be on the same axis and shall be fully bi-directional with respect to flow through the valve. Butterfly valves of diameter greater than 200 mm shall be fitted with geared actuators unless directed otherwise by the S.O. Ratchet action lever actuators shall be provided to smaller sized valves.

(iv) Working pressures and flanges for the valves shall be to suit the system max working pressure but as a minimum shall be in compliance with ISO PN 10 for all valves.

(v) Fabrication materials shall be as follows:

1) Bodies shall be fabricated from Grade 316 stainless steel.



2) Bodies fabricated from ductile iron with fusion bonded epoxy coating internally and may be used upstream of the MF units.

3) Discs shall be fabricated from Grade 316 stainless steel.

4) Seats shall be field replaceable EDPM complying with BS 6920.

5) Shafts shall be Grade 420 stainless steel.

6) Bodies shall have integrated actuator plate in accordance with ISO 5211.

(vi) Valves shall be fitted with lifting rings.

Knife Gate Valves

(i) Knife gate valves shall be full bore, non-rising spindle type, constructed so that the travelling knife gate is fully enclosed within the body of the valve and provided with a self aligning gland box and packed seal. Packing for the gate shall be changeable without having to remove the valve from the pipework.

(ii) The valve body shall be fully cast 316 stainless steel or SG iron. Knife gate, stem, spindle, studs, bolts and nuts shall be stainless steel. Operating nuts for manually operated valves shall be of gunmetal, phosphor bronze or aluminium bronze. Valves shall be provided with a resilient seat and self cleansing channel outlet. Valves shall be drip proof in either direction of flow.

(iii) Limit and proximity switches for position indication shall be fitted where necessary.

(iv) Working pressures and flanges for the valves shall be to suit the system max working pressure but as a minimum shall be in compliance with ISO PN 10 for all valves.

Non-Return Valves

(i) Non-return valves shall be of the dual flap resilient seated check type. The valves shall be wafer type and with flanged connections for diameters greater than 450 mm.

(ii) The valves shall comply with the applicable ISO standards. Manufacture shall be to ISO 9001. All valves shall be hydraulically tested as per ISO 5208 and test certificates shall be provided.

(iii) Working pressures and flanges for the valves shall be to suit the system max working pressure but as a minimum shall be in compliance with ISO PN 10 for all valves.

(iv) Fabrication materials shall be as follows:

1) Bodies shall be fabricated Grade 316 stainless steel.

2) Shafts to dual flap check valves shall be Grade 420 stainless steel.

3) Discs and springs to dual flap check valves shall be fabricated from Grade 316 stainless steel.

4) Seats to dual flap check valves shall be field replaceable EDPM complying with BS 6920.

(v) Valves shall be fitted with lifting rings.



Air Valves

(i) Air valves shall be of the double ball / orifice kinematic type.

(ii) Valve bodies shall be fabricated from Grade 316 stainless steel or fusion bonded epoxy coated internally and externally ductile iron. Balls shall be rubber coated grade 316 stainless steel. The large orifice shall be fitted with a neoprene sealing ring. The small orifice shall be manufactured from Grade 316 stainless steel.

(iii) Working pressures and flanges for the valves shall be to suit the system max working pressure but as a minimum shall be in compliance with ISO PN 10 for all valves.

(iv) All air valves shall be provided with flanged butterfly valves for isolation of the valve from the main pipelines. The butterfly valves shall be of the same pressure rating as the adjoining air valve.

Eccentric Plug Valves

(i) Eccentric plug valves shall be of the non-lubricated type with resilient faced plugs. The valves shall be fitted with corrosion resistant seats which shall have a welded-in overlay of high nickel content on all surfaces in contact with the plug. The weld overlay shall have a minimum total thickness of 6 mm. The valves shall have permanently lubricated, stainless steel bearings in the upper and lower plug stem journals. For valves larger than 600 mm diameter, the valves shall have bronze bearings with stainless steel sleeves in the upper and lower plug stem journals.

Safety Valves

(i) All safety valves on pressure vessels or pressure systems shall be to the requirements of BS 1123.

Globe Valves

(i) Globe valves of 50 mm diameter or less shall be of the threaded, bevelled bronze disc, ductile iron body, bolted bonnet and handwheel operated type.

(ii) Globe valves larger than 50 mm shall be of the flanged, bevelled bronze disc, ductile iron body, bronze mounted, outside screw and yoke, handwheel operated type.

Solenoid Operated Valves

(i) Solenoid operated valves, 50 mm and larger, shall be of the diaphragm actuated, spring loaded, single seat composition disc, packless globe valve type controlled by a suitable solenoid pilot valve.

(ii) The solenoid pilot valve assembly shall be enclosed in a dust and waterproof cover and shall be provided with a manual operator.

(iii) The valves shall have ductile iron bodies with non-magnetic stainless steel stems, renewable bronze seats, synthetic rubber discs, nylon fabric diaphragms bonded with synthetic rubber and stainless steel springs.

(iv) Solenoid operated valves, less than 50 mm in size, shall be of the direct acting single integral seat, full pipe area, globe type. They shall be of all bronze construction with tight seating, renewable composition discs and shall be provided with a manual operator.



(v) Solenoid operated valves shall be of the normally closed, energised-to-open type, unless otherwise indicated in the drawings or required for the particular service.

Ball Valves

(i) Valves shall be non-lubricated and shall have semi steel bodies of stainless steel type 351 and balls of stainless steel type 316. All other parts in contact with the flow shall be of stainless steel type 316. The seals and seats shall be PTFE and shall be easily replaceable using no special tools. Stem packing shall be reinforced Teflon and shall be adjustable while the valve is conducting flow and replaceable without removing the valve from the line. Tail piece gasket shall be PTFE.

(ii) Valves 150 mm or less in diameter shall be wrench operated. Valves greater than 150 mm in diameter shall be handwheel operated through a worm gear. Port position shall be plainly visible to the operator by means of an indicator.

(iii) Balls shall be free floating to minimise wear and shall be automatically cleaned. Valves shall control flow in either direction. Valves shall be regular port. Valves 50mm and larger shall have flanged connections. Valves less than 50 mm shall have NPT threaded connections.

Diaphragm Valves

(i) Diaphragm valves shall accord to BS EN 13397 and shall be arranged for clockwise closing. The valves shall be of the straight or weir type as detailed. The requirements for ancillary equipment shall be as for penstocks. Body lining and diaphragm shall be of materials suitable for the fluid or gas being carried.

Tests and Inspection of Valves

(i) All valves testing shall comply with the applicable ISO standards. Manufacture shall be to ISO 9001. All valves shall be hydraulically tested as per ISO 5208 and test certificates shall be provided.

(ii) The valves may be subjected to inspection by the S.O. or his representative during all phases of manufacture.

(iii) Castings shall be clean, sound and without defects. Any casting in which an attempt has been made to conceal defects by caulking, welding, filling or coating without the approval of the S.O. or his representative will be rejected whether it has been previously inspected or not.

(iv) Test certificate shall be submitted for all valves following factory testing and inspection.

(v) Each valve seat and body, before the application of paint but after machining shall be subjected to a hydrostatic test pressure in accordance with the relevant British Standard.

(vi) During the test, the castings and joints shall show no sign of leakage, distortion or defect.

(vii) Every motorised valve subject to testing shall be combined tested with its actuator.

(viii) The valves shall comply with the applicable ISO standards. Manufacture shall be to ISO 9001. All valves shall be hydraulically tested as per ISO 5208 and test certificates shall be provided.



Actuators and Controls

General

(i) Valves requiring actuators are indicated on the P&IDs.

(ii) The Contractor shall be responsible for providing any additional valve actuators that may be required for the safe, automatic functioning and operation of the entire system. The cost for providing additional actuators is deem to be included in the Contract.

Handwheels

(i) All valves shall be closed by a clockwise rotation of the handwheel or handle. The face of each handwheel shall be clearly marked with the words OPEN and SHUT with arrows adjacent to indicate the direction of rotation to which each refers.

Electric Actuators

(i) Compliance with Standards

1) The electric actuator including all components, shall comply with the relevant Singapore and British Standards and shall be in fully compliant with the relevant Statutory Regulations in Singapore.

(ii) Mounting, Type and Enclosure

1) Electric actuators shall be mounted on the driven equipment as required and shall be of the type driven by an electric motor through a gear reduction unit with handwheel override, and shall incorporate torque and limit switch mechanisms and position indicator.

2) The actuator housing shall incorporate the motor contactors, emergency stop, hand controls, remote local selector, open/close position switches and all electrical controls to provide fault and status monitoring via volt free contacts and remote actuation by a 24 V DC control circuit. In addition, modulating valves shall be controlled using a 4-20mA signal.

3) The electric actuator with gear reduction unit and electric motor shall be totally enclosed in a robust cast iron housing. All access openings and inspection ports shall be gasketed and covers secured with set screws. All external nuts, bolts, washers, studs and screws shall be type 316 stainless steel.

(iii) Degree of Protection Provided by Enclosures

1) The degree of protection provided by enclosures for the electric actuator, including the motor and terminal box shall be not less than IP67.

2) Electric actuators installed in the sump or below water level shall be IP68 and waterproof.

(iv) Gear Reduction Unit

1) The motor shall operate the driven equipment through a robust single or double reduction gear reduction unit designed for the purpose.

2) The gear reduction unit shall be directly mounted on the driven equipment, via an adapter if necessary, so that all actuating forces are internal to the equipment.



3) The gear reduction unit shall be a sealed unit, lubricated for life with a suitable grease.

4) Mechanical limit stops for the actuator shall be on the input side of the drive and not the output shaft.

5) Worm wheels and worms shall be of suitable materials proven in service. Wheels shall be cast iron or bronze and worms shall be of hardened alloy steel, ground to an accurate profile. The wheel shall be 360º rather than a segment to allow repositioning to allow for wear when necessary. Worm drives shall be self-locking.

6) All external fasteners shall be of suitable grade of stainless steel.

7) The gear reduction unit shall be selected so that the valve moves from one extreme position to the other in 30 seconds.

(v) Mounting of Actuators

1) Actuator shall be mounted so that the handwheels are readily accessible by the operators. Handwheels shall have horizontal shafts and the shaft height shall be between 750mm and 1200mm from the walkway or access platform level.

(vi) Handwheel Override

1) The handwheel override operation shall be mechanically independent of the motor drive. The manual drive shall disengage when the motor drive is started and shall automatically lock out when the motor drive is operating. The handwheel shall not rotate during power operations.

2) A non-corrodible metal label shall be provided and engraved to indicate the direction of operation of the handwheel to open or close the valve.

3) The maximum force required to operate the mechanical shall not exceed 160 N at the handwheel rim.

4) Clockwise rotation of handwheels shall close valves and penstocks and shall raise weirs.

(vii) Bearings

1) All bearings shall be ball or roller bearings rated in accordance with AS 2729 “Rolling Bearings - Dynamic Load Ratings and Rating Life - Calculation Method” with factors a1, a2 and a3 equal to one to give a B10 bearing life of 100,000 hours minimum.

2) Bearings shall be greased for life with a suitable proven grease.

(viii) Position Indicator

1) All actuators (or alternatively the driven device) shall be fitted with a position indicator which shall provide a clear, positive and continuous indication of the position of the driven device.

2) The position indicator shall be readily observable by an operator standing

on the floor or walkway near the device or actuator.

(ix) Travel and Torque Limits



1) Actuators shall be fitted with travel limit switches and over-torque limit switches.

2) Travel limit switches shall be readily adjustable in the field without the necessary to use special tools. Travel limits shall be set by the Contractor to suit the equipment to which the actuator is fitted.

3) Over-torque limit switches shall be factory set to suit the application.

(x) Pneumatic Valve Actuators

1) Remotely controlled actuators on valves used to open or close the valve shall be of the pneumatic type. Pneumatic cylinders construction shall have aluminium or stainless steel bodies, 316 stainless steel shafts and fastenings and suitable for operation from a compressed air system with a pressure range between 500 kPa and 1000 kPa. Pneumatic cylinders shall be of the double acting type.

2) All automatic valves shall also be capable of manual operation via the solenoid.

(xi) Solenoid Valves

1) All solenoid valves shall be from a single supplier. All solenoid valve coils shall operate with LED indicator in the body of the valve on 24 V DC current. All coils shall be continuously rated 24 V DC with a power consumption of less than 15 watts with protection to IP65.

2) Solenoid valves shall be fail-safe.

3) Coils shall be fully encapsulated and have class ‘B’, ‘E’ or ‘F’ insulation.

4) Solenoid operated valves on compressed air lines shall be specially constructed for non-lubricated air service. All valves shall be equipped with a manual means to operate the valve in the case of power failure. Valve body shall be stainless steel when used in corrosive environment or exposed weather.

5) Valves shall be installed such that they are easily and safely accessible for operating and maintenance purposes. Valves shall not be fitted in an inverted position.

6) Pilot solenoid type valves shall include a stay put manual override device that can be operated without the use of tools i.e. by hand.

(xii) Position Indication

1) Valves supplied with actuators shall have inductive proximity switches (2 or 3 wire 24V dc type) to show when the valve is either fully open or fully closed.

2) All modulating and flow control valves shall be provided with visual indication of the valve position as well as 4-20 mA/pneumatic positioners.

Corrosion Protection



All equipment supplied under this Contract shall include complete corrosion protection systems, which as a minimum shall meet the following specifications and shall have a minimum coating life of 15 years.

Piping

(i) Steel

1) All steel pipe work exposed to atmospheric conditions (indoors or outdoors) shall be abrasive blast cleaned. Prior to blast cleaning all surfaces shall be solvent cleaned to remove all deposits of grease oil or other solvent soluble contaminants. Steel shall be allowed to dry prior to abrasive blasting.

2) All pipe work shall be coated with primer and paint as described below with the exception of submerged or buried pipe work. Blast cleaned surfaces shall be treated or primed within 4 hours of preparation.

• Primer coat pipe work with Dulux Zincanode 304 or an approved equivalent to a minimum of 75 micron

• Second coat Dulux Amourcoat 385 or approved equivalent (red oxide colour) to a minimum of 125 micron

• Final coat Dulux Luxathane R or approved equivalent to a minimum dry film thickness of 50 micron

(ii) Steels Immersed in Water

1) All steel pipe work immersed in water shall be abrasive blast cleaned to Class 3. Prior to blast cleaning all surfaces shall be solvent cleaned to remove all deposits of grease oil or other solvent soluble contaminants. Steel shall be allowed to dry prior to abrasive blasting.

2) All submerged pipe work shall be coated with primer and paint as described below. Blast cleaned surfaces shall be treated or primed within 4 hours of preparation.

• First coat Dulux Buildicoat or approved equivalent to a minimum of 125 micron

• Final coat Dulux Buildicoat or approved equivalent to a minimum dry film thickness of 125 micro

Mechanical Equipment and Fabricated Items

(i) Mechanical Equipment & fabricated items - exposed to atmospheric conditions (internal/external)

1) All steel surfaces exposed to atmospheric conditions (indoors or outdoors) shall be abrasive blast cleaned to Class 2.5 prior to galvanising. Prior to blast cleaning all surfaces shall be solvent cleaned to remove all deposits of grease oil or other solvent soluble contaminants. Steel shall be allowed to dry prior to abrasive blasting.

2) All equipment shall be coated with primer and paint as described below with the exception of submerged or chemical area equipment. Blast cleaned surfaces shall be treated or primed within 4 hours of preparation.

• Primer coat pipe work with Dulux Zincanode 304 or approved

equivalent to a minimum of 75 micron.



• Second coat Dulux Amourcoat 385 or approved equivalent (red oxide colour) to a minimum of 125 micron

• Final coat Dulux Luxathane R or approved equivalent to a minimum dry film thickness of 50 micron

(ii) Equipment & Fabricated Items – Submerged

1) All steel pipe work immersed in water shall be abrasive blast cleaned to Class 3. Prior to blast cleaning all surfaces shall be solvent cleaned to remove all deposits of grease oil or other solvent soluble contaminants. Steel shall be allowed to dry prior to abrasive blasting.

2) All submerged pipe work shall be coated with primer and paint as described below. Blast cleaned surfaces shall be treated or primed within 4 hours of preparation.

• First coat Dulux Buildicoat or approved equivalent to a minimum of 125 micron

• Final coat Dulux Buildicoat or approved equivalent to a minimum dry film thickness of 125 micron.

Structural Steel

(i) All steel surfaces exposed to atmospheric conditions (indoors or outdoors) shall be abrasive blast cleaned to Class 2.5 prior to painting. Prior to blast cleaning all surfaces shall be solvent cleaned to remove all deposits of grease oil or other solvent soluble contaminants. Steel shall be allowed to dry prior to abrasive blasting.

(ii) All steel surfaces immersed in water shall be abrasive blast cleaned to Class 3 prior to painting. Prior to blast cleaning all surfaces shall be solvent cleaned to remove all deposits of grease oil or other solvent soluble contaminants. Steel shall be allowed to dry prior to abrasive blasting.

(iii) All miscellaneous steelwork including bolts shall be hot dipped galvanised to AS1650 and top coated with paint as described below with the exception of walkway gratings, which shall be hot dip galvanised only

1) Spot prime Intergard 251 or approved equivalent

2) First coat steelwork Intergard 251 or approved equivalent

3) First coat bolts Intercure 200 or approved equivalent

4) Second coat Interfine 629 or approved equivalent

Workmanship and Practices

(i) Generally all surface preparation and coating shall be performed in a neat and workman like manner.

(ii) No work is to be done in conditions that will detract either from the quality or from the appearance of the painting in any way. If any work is done under such conditions it will be rejected if unsatisfactory. Pipes and equipment will preferably painted off site.

(iii) Before commencing blast cleaning the contractor shall first remove all surface contaminants which will not be effectively removed by subsequent surface preparation. Remaining weld splatter, slag and areas of heavy rust must be removed



(iv) Application of paint shall be in the form of conventional or airless spray except where this may contaminate the local environment, in such case the contractor shall seek approval of the S.O. for alternative application methods.

(v) All equipment and pipe work shall be handled in a manner so as to preserve the coating in the best practicable condition. To this end all paint work shall be fully cured prior to transportation.

(vi) The Contractor shall make good any damage to surface treatment after the completion of manufacture and installation using the same kind of paint that was originally used.

(vii) Above ground steel pipework shall be protected in accordance with the above, or equivalent.

(viii) To increase the coating life and to prevent corrosion and buried continuously welded pipework systems, an Impressed Current cathodic protection shall be installed. The cathodic protection anodes shall be installed such that the system is functional with the reservoir operated at the low water levels, depth of 0.5 metre. The Contractor shall engage an experienced and reputable designer to design the cathodic protection.

(ix) The paint system used shall be compatible with the cathodic protection system.

Lifting Equipment

All relevant drawings and calculations of the lifting equipment shall be submitted to the S.O. before any fabrication and installation is carried out.

Monorail Hoist

(i) Monorail hoist shall comprise an electric hoist and a rolled steel joist. The electric hoist block shall be provided with geared hand travel four wheel trolley suitable for running from a rolled steel joist.

(ii) The lifting wire rope shall be of best plough steel and of such length to allow a lift to be made from required level to loading level at ground floor level without re-slinging. The hoist mechanism shall be controlled from a hold on push button pendant. The pendant shall be suspended 1,300 mm above ground floor level.

(iii) Cables feeding the hoist unit and down shop cables shall be flexible cables suspended from carriers sliding on taut wires.

(iv) The lifting equipment shall included a triple leg chain sling with hooks; a suitable wire rope sling; and a nylon rope sling. The slings shall be of suitable length and strength to enable a safe lift to be made of all relevant items of equipment on the pumping station.

(v) The lifting equipment shall bear a permanent inscription on each side legible from ground floor level stating the safe working load. The inscription shall read: "Safe Working Load .....(....) Tonnes.

(vi) The electric drive motors shall be fitted with electro-magnetic brakes to prevent over travel on release of the control button.

(vii) End stops and limit switches are to be installed to prevent over travel and over coiling of the lift rope.



Monorail Chain Block

(i) The chain block shall be provided with geared hand travel four wheel trolley suitable for running from a rolled steel joist.

(ii) The lifting chain shall be of best quality corrosion resistant steel or steel alloy, of such length to allow a lift to be made from the ground floor level to loading level without re-slinging.

(iii) The operation of the chain block shall be manual and, one man of average stature and strength shall be able to operate it with reasonable ease from the floor level.

(iv) A triple leg chain sling with hooks, a suitable wire rope sling and a nylon rope sling shall be provided. The slings shall be of suitable length and strength to enable a safe lift to be made of all relevant items of equipment in the pumping station.

(v) The lifting equipment shall bear a permanent inscription on each side legible from ground floor level stating the safe working load. The inscription shall read: "Safe Working Load .........(....) Tonnes"

(vi) An overload limiter shall be incorporated in the chain block.

(vii) Provisions shall be made to prevent over travel or over coiling of lift chain.

Handrailing

Handrailing shall be anodised aluminium alloy to BS EN 573 and BS EN 755 and comply with BCA requirements. The rails, standards etc. shall have an external diameter of not less than 38 mm.

Rails are to be curved to smooth radii at bends and corners and joints shall be arranged to be made at standards. The external finish of all the railing shall be smooth and free from blemishes and rough areas.

The standards shall be 1,100 mm high with three horizontal rails at heights of 1,100 mm, 755mm and 410 mm. The standards are to be at generally not more than 1,400mm centres fixed by means of baseplates 115 mm diameter and 10 mm thick with three bolt fixings. The baseplates may be flat or side plate type dependent on the fixing position and support. Toe plate of 125mm height shall be provided.

Fixed Platforms, Walkways, Stairways and Ladders

The staircases and walkways are to be formed by the bolting of structural members to the concrete, no supporting members may be built in. The use of stanchions will not be permitted unless it can be shown that support by other means is impracticable.

Stair treads are to be purpose made with a rounded front nosing and rear and side trimming. The treads are to be firmly bolted in position and the arrangement, width, height, and going of treads shall be conducive to safety. The Contractor shall submit detailed arrangement drawings and shop drawing to the S.O.

Access platforms, and stairs or ladders where applicable, shall be provided for convenient access to all equipment requiring access for maintenance, lubrication, adjustment or control. In this context, maintenance includes the replacement and maintenance of all membranes and instruments, pumps, valves, fittings, flanges, gaskets and all other instrument tapping points.



Any access platforms that could prevent the removal of adjacent plant shall be of a demountable type.

Platforms, galleries and stair treads shall, wherever possible, be constructed of open grid steel flooring.

On all steel flooring areas around openings, edging strips (toe plates, kick plates) extending to a clear height of not less than 125 mm above the platform or gallery level and of a thickness of not less than 6 mm shall be provided. Where it is necessary to cut floor panels to give local clearance to pipes, etc., the portion left in situ must be finished with edging strips in such a manner that no exposed edges of the grid flooring remain. All edging strips shall be welded to the grid flooring before galvanising.

The grid flooring shall comply with Australian standard AS 1657 - “SAA Code for Fixed Platforms, Walkways, Stairways and Ladders” or other equivalent standard. Load bearing bars shall be not less than 5 mm thick, the cross rod pitch shall not be greater than 60mm.

Access stairs and ladders shall comply with AS1657 - “SAA Code for Fixed Platforms, Walkways, Stairways and Ladders” or other equivalent standard.

All stairways shall have an inclination not exceeding 45° to the horizontal.

The use of ladders shall be kept to a practicable minimum. Where ladders are approved for use they shall be of steel, have an inclination of 70° to the horizontal and a minimum width of 450 mm.

Steel access stairs shall have grid type treads with each edge clearly distinguishable in dim light.

All stairways, platforms and walkways shall be enclosed by hand railing on both sides unless on one side there is less than 100 mm between the walkways and adjacent structure. In such a case, hand railing need be supplied on one side only. Handrails shall comply with AS1657 - “SAA Code for Fixed Platforms, Walkways, Stairways and Ladders” or other equivalent standard.

Galvanised hand railing (preformed tubular system) shall be provided for all platforms, walkway and stairs.

All grating floor sections shall be removable and the main support beams shall be positioned to provide clear access for the installation and removal of pipework, valves and pumps. This shall also apply to areas outside the buildings where mobile cranes will be employed.

Ladders

Ladders shall be constructed of aluminium alloy to BS EN 537 and BS EN 586, rungs shall be of substantial section serrated tube to enable sure hand and foot holds. The ladders shall be of all welded construction and shall comply with the requirements of BS 4211 for the spacing of stringers, rungs, safety hoops and hand holds. They shall be fixed with stainless steel bolts, nuts and washers.

Electrolytic Action



Where aluminium surfaces are attached to or in contact with concrete surfaces suitable PVC washers and packings are to be used to isolate the metal. Where large areas of contact are arranged the concrete surface may be treated with bituminous paint, or the aluminium surface may be coated with coal tar epoxy paint.

Suitable measures are to be taken throughout the erection of the metalwork to avoid any metal contacts likely to induce electrolytic action and corrosion.

Cleaning on Completion

On completion of the work, all floors, bright parts, glass panels etc., which may have become spotted or touched with paint shall be cleaned down and all left clean to the satisfaction of the S.O.

As Constructed Details

"As Constructed" details shall be provided as follows:

(i) Drawings of all pipework shall be reissued with as constructed amendments. These drawings shall be marked “As Constructed”.

(ii) Electronic copies of the originals of the design drawings issued “For Construction” shall be amended by the Contractor with as constructed details indicated by “clouding. Dimensioned details shall be provided where pipes, etc have been deviated around other services.

Substantial Completion shall not be issued until the "As Constructed" details have been received in both electronic and “hard” formats and approved by the S.O.

Drawings

The following is an indicative list of all items for which drawings shall be prepared and submitted to the S.O., by the Contractor:

(i) General Arrangement Drawings

(ii) Equipment Layouts

(iii) Piping Details And Isometrics

(iv) Flange Details

(v) Valve Details

(vi) Dismantling Joints Details

(vii) Schedules of Pipes and Fittings

(viii) Fabrication Details (including welding details)

(ix) Bolt Schedules

(x) Pipe Support Details.

(xi) Labelling Details

(xii) Corrosion Protection Details

(xiii) Concrete supports

(xiv) Testing Details

END OF SECTION
