Method Statement for HVAC Piping Installation Work

Method Statement for HVAC Piping Installation Work

Method Statement for HVAC Piping Installation Work

Contents

  1. PREAMBLE
  2. INTRODUCTION
  3. HEALTH AND SAFETY
  4. DEFINITIONS
  5. SPECIFICATIONS CLAUSES
  6. REFERENCES / CODE OF PRACTICES
  7. INSTALLATION PROCEDURES
    1. EQUIPMENT   
    1. DELIVERY, STORAGE AND HANDLING
    1. INSTALLATION PREPARATION
    1. PAINTING
      1. SURFACE PREPARATION
      1. PAINT SCHEME
      1. APPLICATION OF PAINT
      1. DAMAGED SURFACES
    1. JOINTING METHODS
      1. SCREW JOINTS
      1. WELDING
        1. FILLER METALS
        1. WELDERS  APPROVAL
        1. FIT-UP AND SURFACE PREPARATION
        1. WELDING PROCESS
        1. WELDING REPAIRS
  • BRAZING AND SOLDERING  
    • FILLER METALS AND FLUXES
    • FIT-UP AND SURFACE PREPARATION
    • BRAZING PROCESS
    • DIELECTRIC FITTINGS
    • MECHANICAL PIPE COUPLINGS
    • FLANGED JOINTS
    • METHOD OF INSTALLATION
      • GENERAL
      • SLEEVES
      • PIPE ESCUTCHEONS 
      • PIPE EXPANSION JOINTS
      • VALVES
      • STRAINERS
      • AIR VENTS
      • DRAINS
  • HYDROSTATIC TESTING
  • FLUSHING
  • IDENTIFICATION
    • VALVES TAGS AND CHARTS
    • PIPING IDENTIFICATION AND CODING
  • QUALITY ASSURANCE
  • TUNNEL PIPING INSTALLATION.
    • INSTALLATION METHOD OF HOT WATER PIPE IN TUNNEL.
  1. Preamble :

This procedure defines the method used to ensure that the HVAC piping system

Installation comprising all pipes, tubes, valves, fittings, reducers, expanders, nipples,

Vents, anchors, brackets, sleeves and all accessories, components connected thereto as

An integrated part of the HVAC piping system to be correct and acceptable and

Conform to the contract documents, drawings and the general specifications. 

The preface explanation of the proposed stages statements for the HVAC piping system

Installation works would briefly clarify our understanding of the services to be provided for MALL OF EGYPT Development project as well as our understanding of site conditions and logistic, thereto stages of construction to be adapted in our work.   

Stages of site installation of pre-fabricated and site fabricated piping for different systems

To be adapted to our work shall comply with the general conditions and specifications  

Of the contract, yet the following aspects must be highlighted as an important factor for  

The  installation work.  

  • The importance of the safety to this project.
  • The importance of meeting project milestone dates.
  • The importance of the final product quality.
  • Introduction :

The procedure for piping works installation includes the following steps:

  • Define responsible personnel.
  • Obtain Besix – Orascom JV permit to work.
  • Establish a fabrication workshop on site.
  • Create a safe access to the areas where piping installation works are to be done.
  • Preparation works to establish safe “confined spaces “.
  • Test commission and handover the work.
  • Health and Safety :

This section covers the safety precaution procedure, containing the following

Points: 

  • Lifting, welding and all installation equipment and tools shall be in safe and good working conditions, damaged cables & power cables shall be replaced.
  • Cranes shall be properly inspected and operated by a certified operator and proper lifting signs are to be used.

      Welders shall wear the following:-

  • Leather jackets.
  • Cap sleeves or aprons.
  • Welder’s helmet.
  • Leather protection gloves.
  • Safety shoes.
  • (Samples shall be submitted to Besix – Orascom JV, HSE manager for approval).  
  • Grinding works shall wear face shields in addition to the PPE when grinding.
  • Painters shall wear masks when painting, sandblasting operators shall wear respirators when sandblasting.
  • All personnel in the working area shall wear, as a minimum, safety shoes, safety helmets and protective glasses.
  • Communicating radios shall be used by engineers and supervisors inside the tunnel.
  • Prior to work in the confined space a “permit to work check list” (Besix– Orascom JV. HSE program-attachment-J) shall be filled-in and approved by Besix – Orascom JV HSE Department.
  • Prior to hot work activities a “hot work permit “( Besix–Orascom JV. HSE program-attachment shall be filled-in and approved by BESIX – Orascom JV HSE Department.
  • Safety precaution signs shall be provided in the working area.
  • Working area shall be clean, free of oil, grease and obstacles, and surrounded by
  • Warning tapes, House keeping shall be fully enforced.
  • All material shall be stored in a secure, safe area.  
  • Fire extinguishers shall be available with the working groups during the work.
  • Rolling scaffolding shall be safe and in a good position to allow performing the work in a safe manner, only green tagged scaffolding to be used and working on red tagged scaffoldings shall be forbidden.
  • No access under lifting equipment shall be permitted during operation.
  • Adequate portable white and non-oxygen consuming lighting systems shall be provided.
  • Toxic, flammable and oxygen gases shall be measured and kept within the permissible percentage.
  • Gas cylinders with flash back arrestors shall be kept in up right position and chained to prevent any damage to the gas supply hoses.    
  • Approved evacuation / rescue plan shall be issued & tried prior to work and to be continuously updated according to the work station change.
  • A first aid box must be available with each work group.
  • Besix–Orascom JV emergency facilities shall be used in case of emergency.
  • Potable water must be available at the work area.  
  • Definitions :
  • ASME                           American Society of Mechanical Engineers
  • AWS                             American Welding Society
  • HVAC                          Heating , Ventilation and Air Conditioning 
  • SMAW                          Shield Metal Arc Welding  
  • PPE                              Personnel Protective Equipment
  • DFT                              Dry Film Thickness
  • NDT                             Non Destructive Testing
  • RT                                 Radiographic Test
  • Specification Clauses :
  • Specification section:  
  • Div. 15010 General provisions for mechanical work.
  • Div. 15055 Painting.
  • Div. 15060 Piping Specialties.
  • Div. 15100 Valves.
  • Div. 15411 HVAC Pipes and Pipe fittings
  • Div. 15990 Test and Balancing.
  • References / Code of practices :
  • The piping installation activities shall be carried out in accordance with the international codes, standards and the client specifications stipulated in the contract documents:
  • ASME IX   (Welding, brazing and Welders, braziers Qualification Code).
  • ASME 31.1    (Pressure Piping code).
  • ASTM (American Society for Testing and Materials).  
  • ANSI ( American National Standards Institute )
  • Installation Procedures :
  • Equipment :

–   Installation equipment will be as follow:

  • Pipe cutting machines.
  • Welding machines.
  • Fork lifts.
  • Hydraulic jacks.
  • Grinding and drilling machines.
  • Oxy-acetylene gas cutting machine.
  • Welding electrode oven.
  • Rolling scaffolds.
  • Hand tools.
  • Mobile crane.
  • Delivery, Storage And Handling:
  • Material deliveries to the site shall be in such intervals to ensure uninterrupted progress of work.
  • Materials shall be stored to permit easy access for inspection and identification. Pipes shall be kept off ground, using pallet, platform or other supports. Pipes and packaged materials shall be protected from corrosion and deterioration.
  • Material shall not rest on pipes in a manner that might cause distortion or damage to member or other pipes.
  • Storage area must be well ventilated.
  • Material inspection requests (MIR‘s) (attached) shall be submitted at the time material arrives at site.  
  • Installation Preparation  :
  • Mechanical supervisor will instruct the tradesmen regarding the execution of the works and will distribute all necessary approved, latest revision construction drawings.
  • The supervisor will also check that tools and equipment available are in compliance with the contract requirements.
  • All materials and documentation relevant to a particular section of works will be checked by the construction department prior to the commencement of work, ensuring that these are of the correct type as reviewed by the consultant.
  • Before commencement of any construction works, pre-inspection will be carried out on all materials prior to it’s leaving the storage area. The consultants will be invited to attend this inspection at their discretion.
  • Prior to the commencement of any construction works, areas and access will be inspected to confirm that they are in a suitable condition for construction works

      To commence.

  • Painting  :Surface Preparation :
  • Prior to surface preparation and application of primer, the pipes surfaces shall be completely cleaned of dirt, grease, slag, rust and other contaminants. Any rust inside/outside shall be completely removed by blast cleaning or wire brushing. Severely pitted pipes shall not be used. The surface roughness after cleaning shall not exceed the specified value (80μm amplitude of roughness).
  • Pipes should be wiped clean with solvent prior to priming
  • The quality of surface preparation will be attained at the time of priming.
  • Areas to be welded shall be masked off prior to priming, and re-prepared and primed to the same quality after welding.
    • Paint Scheme :
  • The criteria in the following clauses shall be used to define which scheme should be used in a given situation where not specifically given in the paint scheme schedule:
  • SCHEME P/1   :  Internal annulated steel piping in a dry place.
  • Primer               :  Zinc phosphate oil/alkyd primer, 40 microns DFT
  • Finishes             :   Oil/alkyd finish (colour specified elsewhere)
  • SCHEME P/2   :  Internal insulated steel piping in a dry space away from

The building perimeter, where condensation is likely to occur Only in exceptional substances. Includes pipes which are  

Insulated with an integral vapor barrier.

  • Primer               :  Zinc phosphate oil/alkyd primer, 40 microns DFT
  • SCHEME P/3 :   External and light well insulated steel piping in a position  

Which condensation is likely to occur from time to time, and in   

Which the paint is unlikely to be maintained.

  • SCHEME P/4  :  Internal un-insulated steel piping in a position in which

Condensation is likely to occur from time to time, and in which  

Maintenance of the paint is possible.

  • SCHEME P/5        :   External galvanized steel piping works.

                              Surface preparation    :   The various paint schemes shall be as detailed below

  • SCHEME P/1 Surface preparation : As above
  • Primer : Zinc phosphate oil/alkyd primer, 40 microns DFT
  • Finishes : Oil/alkyd finish (colour specified elsewhere)
  • PAINTING SEPT. 2012. CD03 REV. A 15055
  • SCHEME P/2Surface preparation : As above
  • Primer : Zinc phosphate oil/alkyd primer, 40 microns
  • DFT.
  • SCHEME P/3 Surface preparation : Type 1
  • Primer : Zinc phosphate oil/alkyd primer, 40 microns
  • DFT
  • Barrier coat (1) : High build bituminous coating, chocolate
  • brown, 100 microns DFT
  • Barrier coat (2) :High build bituminous coating, black, 100
  • microns DFT
  • SCHEME P/4 Surface preparation : Type 1
  • Primer : Zinc phosphate oil/alkyd primer, 40 microns
  • DFT
  • Barrier : Oil/alkyd MIO barrier coat, 75 microns DFT
  • Undercoat : Oil/alkyd undercoat, 40 microns DFT
  • Finish : Oil/alkyd finish
  • SCHEME P/5 Surface preparation : Etch prime
  • Barrier : Cold tar epoxy, 125 microns DFT
  • Barrier :                      :  Cold tar epoxy, 125 microns DFT      
  • All paints in a single scheme shall be supplied by the same manufacturer.
    • Application of Paint  :
  • All painting shall be carried out by skilled painters under competent supervision.
  • Area where paint will be applied should be as dust free as possible.
  • Each coat of paint shall be applied to a clean and suitable surface to produce a continuous film of paint of uniform and even thickness.
  • As soon as the priming coat has dried, an extra coat of paint shall be applied to all edges, corners, cervices, bolt heads, welds and any similar areas, using the same paint as for the primer but in a contrasting shade.
  • The dry film thickness shall be measured after each coat has dried.  Wet film thickness measurements shall not be used, other than for control purposes.
  • The adhesion of the paint scheme shall be measured and carried out on representative areas chosen to be non-obtrusive in the final condition.  Areas below standard shall be cleaned to bare metal and repainted.
  • The minimum dry film thickness per coat is 40μm.
  • Touch-up painting shall be applied immediately after erection, clean field welds, bolted connection and abraded areas of shop paint.
  • The test areas shall be touched-up. Final finish coat has to be applied after erection.
    • Damaged Surfaces  :
  • The all necessary precautions to minimize damage to steel and to paint coatings during handling, installation and thereafter.
  • Where damage or breakdown has occurred, or in any other place where the paintwork does not comply with specification, the damaged area shall be touched-up to an equivalent standard to the undamaged paint, in such a way that the areas of touch-up shall not be visually apparent.
  • Demonstration to the Besix – Orascom JV that his proposals for touching-up shall include details of surface preparation, area of overlap, type and thickness of paint to be used and any other relevant features, shall produce work in accordance with the specifications.
  • Jointing Methods:Screw Joints:
  1. Full cut threads shall be used as shown below:
Nominal Pipe Size(mm)  Threads/cm   Bore Size      (mm)Thread Length        (mm)Thread Depth       (mm)
            20          5.5      23.02          14       14.29
            25          4.5      28.97          17       17.46
            32          4.5       38.1          18       17.46
            40          4.5      43.66         18.5       17.46
            50          4.5      55.56         19.5       19.05
     
  • Pipes ends shall be cut square, debarred and cleaned.
  • Male thread shall be sealed with a Teflon tape or other approved compound, the use of cotton wicking, lamp-wick or caulking shall not be used.
  • Care shall be taken when handling threaded piping.
    • Welding:  
  • Filler Metals :
  • The filler metals shall be similar to the base metals being jointed; with respect to chemistry, corrosion resistance and mechanical properties.
  • Filler metals electrodes class AWS Class A 5.1-SFA 5.1 shall be used. E6010 Electrodes will be used for welding the root pass(3-4mm) and E7018 electrodes with different diameters will be used for welding the hot and filling passes. Any other class will not be used before approval.
  • Low hydrogen electrode shall be adequately protected against moisture pickup during Storage; these electrodes shall be baked in an oven at (250o C – 430o C) for a minimum of 2 hours prior to use or as recommended by the manufacturer.       
  • Baked electrodes shall be transferred to portable ovens for field used. All electrodes issued to welders and not used within 4 hours shall be returned to the baking oven and re-baked.   
  • Filler metals or electrodes in accordance with manufacturer’s recommendations shall be stored and handled with care to avoid damage.
  • Wet electrodes shall not be used.
  • Use DC welding machine with suitable current/amperage as shown on electrodes box.
  • Welder Approval :
  • All welders shall be qualified and certified by the approved independent test agency according to the ASME IX code.
  • Welders certification shall be submitted to Besix – Orascom JV prior of starting welding activity. 
  • Welder should be field tested in the presence of Besix – Orascom JV /SCG
  • Master file of welder’s qualifications and certification shall be maintained at the site.
    • Fit-up and Surface Preparation :
  • All welded joints fit up, shall be in accordance with the applicable construction code ASME 31.1, (i.e. See attached joint fit up details).
  • No dirt or debris shall be allowed inside pipes prior to their alignment.
  • All beveled pipe ends shall be at a 37.5 degree angle and smooth rough cuts where possible. For each joint and the area adjacent thereto shall be thoroughly cleaned to remove paint, rust, mill scale or dirt to avoid defects in the weld.
  • All cutting and beveling of pipe ends, shall be carried out using a beveling machine

 (I.e. grinders), cutting by an oxy-acetylene torch shall be carried out in the 

Fabrication shop only with correct ratio of Oxygene – Acetylene. Pipe clamps shall be used after alignment of pipe ends to tack-weld joints with 25cm long angles and shall be as follow:

       A-   4 – Tack-welds for pipe sizes up to 250 mm.

       B-   8 – Tack-welds for pipe sizes 300 to 500 mm.

  • The entire circumference of the flange shall be cleaned when matching within the pipe.
  • When butt welding pipes with different wall thicknesses result in an internal misalignment, the end of the pipe with the greater thickness is reduced internally until alignment is achieved, by grinding a 1:4 taper.
    • Welding Process :
  • Welding of piping shall be according to ASME 31.1 Pressure Piping code.
  • Build up welds with stringer bead pass, followed by hot pass, followed by cover or filler passes, eliminate valleys at center and edges of each weld.  
  • Welders shall be certified and qualified. Regular visual inspection for the welds shall be carried out during the production welding.
  • Ensure inter-passes cleaning by means of grinding and brushing. Eliminate of unsound or infused metal, cracks, oxidation, blow holes and non-metallic inclusions, valleys at center and edges of each weld.
  • After finishing welding, welds shall be cleaned by brushing.
  • Vertical weldings will be executed from bottom to top, horizontal pipe welding and overhead pipe welding in two strokes from bottom to top.
    • Welding  Repairs :
  • Unsound welding or defects shall be repaired by means of chipping, grinding or any other suitable means approved by Besix – Orascom JV /SCG and re-welded according to codes and specifications.
  • Brazing and SolderingFiller Metals and Fluxes:

Joints shall be made with:

  • Non-corrosive paste flux and 95-5 tin antimony solder ASTM B32, Grade 95TA, cored solder shall not be permitted.           
  • Brazing Filler Metal ASTM B260-62T.
  • Brazing Flux Harmon’s “Handy Flux”.
  • Any other Filler Metal or Fluxes specification shall not be used before approvals.
    • Fit-up and Surface Preparation :
  • Tube ends of tubing shall be square cut and all burrs shall be removed. Outside of tube ends and inside of fitting shall be cleaned with steel wool or emery cloth.
  • Tube shall be inserted to full depth into fitting and soldering shall be in a manner which will draw solder to full depth and circumference of joint.
    • Brazing Process :
  • Brazing shall be carried out according to ASME Code, Section.
  • Silver solder shall be used with a melting point exceeding 595 C o  where noted under piping systems.
  • After joint soldered, excess flux and solder at joint areas of both tubes and fittings shall be cleaned off.
  • Excess solder shall be wiped from joint before it is hardened.
  • Care shall be taken to prevent annealing of fitting and tubing.
    • Dielectric Fittings:
  • Installation for union shall be with threaded or soldered end connection for the pipe materials in which it is installed.
  • Construction of union shall be to isolate dissimilar metals, prevent galvanic action and prevent corrosion.
    • Mechanical Pipe Couplings:
  • Mechanical couplings may be used above 1¼ dia. in lieu of threaded, flanged or welded connections in hot and chilled water circulating systems not exceeding 93Cº and 1,033 K Pa working pressure and must meet the pressure, temperature, support and flexibility requirements of the system in which they are used.
  • Fabricated coupling housings of either malleable iron shall conform to ASTM A‑47 or ductile iron conforming to ASTM A‑536.
  • Construction using approved coupling gasket of synthetic rubber shall be done.
  • Grooved couplings shall hold the gasket in place which bridges the pipe ends.
  • The gasket shall design to be pressure responsive, so that internal pressure serves to increase the seal’s water tightness.  The couplings assemblies are held together with heat treated carbon steel bolts and nuts conforming to a minimum tensile strength of 757,900 K Pa.
  • All pipes shall have grooved ends, designed to accept the mechanical couplings, fabricated of either malleable iron ductile iron or steel.(Victaulic couplings).
  • Flanged Joints:
  • Gaskets shall be provided between all flanges of either copper or steel.
  •  Gaskets shall be 1.5 mm thick and not containing asbestos.
  • Both flange faces shall be cleaned.
  • Number of flange bolts should meet the ASTM recommendations.
    • Method of installation:
      • General:
  • The drawings shall indicate schematically the size and location of piping. 
  • Piping shall meet field conditions and coordination between trades.
  • All pipe and pipe groups shall be installed in straight and parallel lines and on common pipe racks where possible.
  • All changes in direction of piping shall be made with fittings.  Mitered fittings face or flush bushings, close nipples or street elbows shall not be acceptable.
  • All circulating water systems shall be installed to allow air to vent at high points and to drain at low points.
  • Float operated automatic air vents with valves shall be installed at all high points.  Run discharge pipe from air vent to nearest floor drain or slop sink.
  • Drains, 20mm (minimum unless specified otherwise) globe valve shall be installed at every change in level, direction and low points with hose connection and cap chained to valve body.
  • Eccentric reducing fittings shall be used in piping where required for proper draining of the system.
  • All piping connections to coils and equipment shall be made with offsets provided with approved screwed or welded, fittings bolted and gasketed flanges or screwed unions, ensuring that the equipment can be serviced or removed without dismantling the piping.
  • Piping to coils, pumps and other equipment shall be installed at full line size, including valves and strainers.  Reduction in line size may be made only at the connection to equipment and control valves.
  • The drawings shall indicate the size and location of pipe.
  • Pipes shall be installed in straight and parallel lines.
  • All change in direction of pipe shall be made with standard fitting up to 22.5º, less than 22.5º should be fabricated from pipe on site.
  • Automatic air vent with valve shall be installed at the high points and the low points drain shall be connected to the nearest drain point.
  • Concentric reducing fitting shall be used to reduce pipe diameters from size to size.
  • Anchor all pipes to compensate for expansion and contraction shall be installed in such way prevent excessive strains on piping as per approved shop drawings details.
  • For branches of diameter less than the main pipe size by 2 diameter, weldolets will be installed or weld lets may be used where standards fittings required size are not available
  • Miscellaneous drains, vents, relief’s and overflows from tanks, equipment, piping, relief valves, pumps, etc., shall run to the nearest open sight drain or roof drain.  Drain valves shall be provided whenever required for complete drainage of piping,

including the system side of all pumps.  Drainage piping shall not run across floors, walkways, work areas etc.  Type of drain required and location shall be coordinated with appropriate trade.

  • Flexible connection joints out building expansion joints to be provided and approved from consultant.
  • Anchor and guide all piping to compensate for expansion and contraction shall be installed is such way prevent undue strains on piping or apparatus.   3‑elbow swings shall be provided at all branch riser takeoffs to take up expansion.  Branches shall be arranged to take up motion of riser.
    • Sleeves:
  • Pipe sleeves shall be provided of types indicated for each pipe passing through walls, partitions, floors and roofs. Sleeves shall be checked and installed by the construction team as follows:-
    • Clearance :
  • 15 mm Max. between outside of pipe ( or insulation on insulated  pipes )

And inside of sleeve in floors and fire rated partitions.

  • 40 mm Max. between outside of pipe (or insulation on insulated  pipes ) 

And inside of sleeve in non-fire rated floors & partitions.

  • Length schedule:
  • Floors:   Equal to depth of floor construction including finish. In waterproof floor  

Construction sleeves to extend min. of 50mm above finished floor level.

  • Roofs:    Equal to depth of roof construction including installation plus 100mm.
  • Walls & Partition :  Equal to depth of construction and terminated flush with wall 

Surface.

  • Sleeve Caulking & Packing Schedule: 
  • Designated A :     Pack space between pipe and sleeve with rockwool or fibre glass

and caulk water tight with approved compound.

  • Designated  B :    Pack space between pipe or pipe covering and sleeve with 

Mineral wool and caulk water tight.

  • Sleeve application Schedule: 
Sleeve No.TypeLocationClucking& packing type
4Coated cast iron with caulking recess, flashing flange and flashing clamp ring.Membrane water proof and wall construction        B
2Standard weight galvanized steel pipe.Non-membrane water proof & wall construction when flashing is required   A or B
11.31 mm galvanized steel.Interior walls and partitions                                    B
2Standard weight galvanized steel pipe.Floors B
3Standard weight galvanized steel pipe with a continuously welded water stop of 8mm steel plate extending 150mm all around.Exterior walls & ground floor slabA
  • Pipe escutcheons:
  • Approved escutcheons shall be provided on all exposed piping passing through walls, floors, partitions and ceilings.
  • Close fitting metal escutcheons shall be provided on both sides of piping through fire rated walls, floors, partitions and ceilings, whether exposed or not.
  • Size          :  The inside diameter to closely fit pipe outside diameter or outside of 

Pipe insulation where pipe is insulated.

Escutcheon outside diameter shall cover the pipe penetration  

Hole in walls, floors, partitions or ceilings.

  • Material   : Finished spaces:        Anodized aluminum or chrome.

Unfinished spaces:   Plain brass, cast iron or aluminum.

  • Fixing      :  Will be fixed by setscrew
    • Pipe Expansion joints:
  • Expansion joints and expansion loops shall be furnished and installed in such manner as to allow for the thermal expansion and contraction without any strain

To connections at equipment or interconnecting piping. 

  • Bellows types and Expansion compensator shall conform to the standard of the expansion joint manufacturer’s Association, pressure rated for the system in

Which it is installed.

  • Bellows Type: Joint of stainless steel corrugated bellows shall be constructed with contour control rings, carbon steel inner liner and carbon steel shrouds.  End connections suitable for the piping systems in which installed shall be provided.
  • Expansion Compensators:  Compensator of stainless steel corrugated bellows and brass telescoping shroud shall be constructed.  End connections suitable for the piping systems in which installed shall be provided.
    • Valves
  • All valves installation shall be only in the upright or horizontal positions, unless otherwise shown, to permit full stem operation.
  • All valve installation shall be in as accessible location to facilitate operation, repair or replacement and of the same size as the upstream pipe, unless otherwise indicated.
  • Gate valve shall be used for shut‑off unless otherwise shown on the drawings or specified.
  • For balancing of water systems, the following types of valves shall be used unless otherwise shown on the drawings or specified :
    • Balancing Water Systems: Globe valves or lubricated plug valves with venture meter at each balancing point, or calibrated balancing valve with meter kit.

Plug Valves:  Operating wrench shall be providing for valves up to150mm;  

One wrench for each size of valve, and a worm gear operator for valves  

200mm and above.

  • A gear operator shall be included on all valves 150mm and above with a chain operated hand wheel where the valves are above the 2.4M level in mechanical equipment spaces and plant rooms.
    • A lubricating gun shall be provided one for every 50 valves and a one year supply of lubricant for each valve, suitable for the valve service.
  • Ball valves may be used for shut‑off in sizes 50mm and smaller in chilled water.  Obtain written authorization from Besix – Orascom JV for the use of these valves.
  • In HVAC butterfly valves are not applicable.
    • Strainers:
  • Strainer with cast iron or cast bronze bodies shall be designed to allow blowing out of accumulated dirt and removal and replacement of strainer screen without disconnection of the main piping.
  • Strainer screen shall be stainless steel and of ample strength to prevent collapsing

     Under shock loading.

  • Strainers shall be furnished and installed in the inlet connection to each pump, each vent, and each automatic valve and elsewhere shown on drawing.
  • Strainers shall be arranged so as not to “trap” pipes, and to facilitate disconnection and opening for cleaning.
  • Installation for the Y-Pattern strainers in waterlines including all pump inlets set in 

     Horizontal and vertical downward run of the pipe.

  • Approved valve dirt blowout connection shall be provided for each strainer 65 mm size and larger. Locate each valve at hand- height and pipe to the nearest floor drain.
  • In the case of strainers under water pressure, the blowout connection shall be terminated in an approved manner at a point where there is no risk of flooding or damage. Nipples and valves full size of strainer blow-off tapping and capped nipples at least 150 mm long in strainers 50 mm and smaller shall be used.
  • Air Vents:
  • Air vent shall have a valve mechanism in the position of which is controlled by a ball float. The action is to vent air automatically.
  • Vents shall be provided with a shut-off cock and strainer, drain piping installation shall be from the air vent outside to the nearest floor drain or slope sink.
  • Manual vents shall be provided where required for additional venting.
    • Drains
  • The construction team shall install drain riser, piping and fittings from galvanized    

                             Steel pipe, arranged with globe or angle valves.

  • Hydrostatic  Testing:
  • Before hydrostatic testing, all devices and equipment which are not designed for the test pressure shall be disconnected, and all openings shall be plugged.        
  • All piping, etc. shall be tested to a hydrostatic pressure at least 1 1/2 times the maximum operating pressure but not less than 1278 kPa for a sufficiently long time to detect all leaks and defects.   Where necessary, piping shall be tested in sections to permit the progress of the job. Hydrostatic tests shall be performed in accordance with ANSI B31.1 by the Contractor in the presence of the Engineer.
  • For ANSI Class 1033 kpa piping, test pressure shall be 1550 kPa
  • For ANSI Class 2067 kpa piping, test pressure shall be 2750 kPa.
  • As a minimum, duration of test at full test pressure shall be six (6) hours for 1033 kpa class systems and twelve (12) hours for 2067 kpa class systems.
  • After this test, the liquid shall remain in the system at full or reduced pressure for an additional six hours.  This period may be used for additional leak checking.
  • Any portions with leaks and/or defects shall be repaired and retested as described above.
  • Test pressures indicated in subparagraphs above shall be measured or achieved at the highest elevation point of the piping portion being tested.  However, the test pressure at the lowest point shall not exceed 1963 kpa psig for the ANSI Class 1033 kpa piping and 3445 kpa for the ANSI Class 300 piping.
  • After hydrostatic testing and additional leak testing is complete, piping flushing chemical flushing and cleaning procedure shall take place. A detailed method statement will be submitted for approved in advance and a preparatory phase inspection meeting will be scheduled.
  • If piping has been previously flushed and cleaned prior to hydrostatic testing, no draining of the piping system is required.
  • Flushing:
  • By-pass shall be provided for cleaning and flushing the lines.
  • After test completion, all piping system and storage tank shall be cleaned from debris, dirt, grease and foreign materials.
  • All piping system shall be flushed and cleaned, after that it shall be immediately filled with water in order to prepare it for service.
  • A specialized company working in the field of water treatment will supervise the flushing procedure.
  • Identification:
  1. Valves Tags and Charts :     
  2. A valve tag shall be installed on every shut-off valve, balancing valve and control valve. 
  3. Valve tag shall be 1.15 mm thickness; 50 mm diameter polished brass with stamp engraved Piping system in 7 mm high letters and sequenced valve number in 21 mm high numbers.
  4. Security the tag shall be fastened to the valve with a solid brass “S” hook and a solid brass jack chain.
  5. A glazed display frame fabricated of finished hardwood or extruded aluminum, glass covered. 
  6. In addition to the framed valve charts, three bound copies of the valve chart shall be furnished.
  7. Piping Identification and coding :
  • A semi‑rigid plastic, color coded, pre‑printed, snap‑on pipe markers, shall be provided identifying pipe contents and direction of flow.
  • For external pipe diameters, including insulation, of less than 150mm, pipe markers, extending 360 degrees around the pipe shall be provided.
  • For external pipe diameters, including insulation, 150mm and larger, pipe markers secured with stainless steel spring fasteners shall be provided.
  • Pipe markers in accordance with the contract and the following shall be furnished:              
OVER‑ALL PIPE O.D. ‑ MM                  LENGTH OF  COLOR FIELD MMSIZE OF  LETTERS ‑ MM
20-3220015
40-5020020
65-15030032
200-25060065
Over 25080095

                                                                        200                20


Color Chart

ApplicationBackground ColorLetter Color
SteamYellowRed
Hot WaterYellowRed
Hot OilRedWhite
Fuel OilYellowBlack
Chilled WaterGreenWhite
Condenser WaterGreenWhite
Make-Up WaterGreenWhite
Feed WaterYellowBlack
GasYellowBlack
Supply/Return AirBlueWhite
Condensate RefrigerantGreenWhite
Toilet/Generator ExhaustBlueWhite
Kitchen Hood ExhaustYellowBlack
  •  24 additional markers of each type for future use by the client shall be provided.
  • Tagging / marking shall be provided every 10m and at all access door locations.
  • Quality Assurance :
  • All work shall be carried out using the specified material in accordance with the general contract document and specifications
  • A- Installer Qualification: have installation experience and a complete piping system installation works in a similar material, design and extent to that indicated for this project and whose work has resulted in construction with a record of successful in service performance.
  • B- Manufacturer qualifications: A firm experienced in manufacturing of the   supports materials complying with international codes and standard i.e. ASTM, DIN, ANSI, ASME, etc. for piping works installation sections and its accessories (Please refer to material submittals of piping systems).
  • C- Quality Control Test Plan: Manufacturer qualifications :
TestTest  ItemRef. StandardRemarks
MaterialsPipingASTM DIN, APIBefore Starting works
Welding  Performance QualificationWeldingASME IXBefore Starting works
Welders Performance QualificationWeldingASME IXBefore Starting works
Visual InspectionWelding jointsASME 31.1  Random Check  
Filler metalsElectrodes , Welding rodsAWS A5.1Random Check
  •  
  • Full time dedicated quality control engineer shall be assigned.
  • Approved independent testing laboratory shall be assigned for performing welder procedure qualifications.
  • Tunnel Piping Installation:
  • Delivery, Site Access & Pipe Preparation:-
  • Transport & Site Access.

Delivery of pipes should preferably be through the gate in the vicinity of the labour camp, thus avoiding transport and the resulting disturbance of the ongoing construction work of other parcel. Upon receiving permission of the proposed access route described above, as area of approximately 2500m will be leveled compacted and prepared as needed to serve as storage or preparation area. (see attached sketches)

(Duration approx. 6 weeks).

  • Pipe Preparations.

The chilled water pipes for the tunnel area will be delivered in 12m length and grooved at both ends, ready for installation by means of victaulic couplings. For certain sections of the tunnel where the expansion / contraction requires additional couplings, to be provided the 12m pipes will have to be cut and grooves will be machined before the pipe is transported into the tunnel.

Welding inside the tunnel is therefore reduced to locations where change of direction or level and branch – off to the different parcels occur only.(at all pipes fittings).

Transport of pipes will be to the west end of the tunnel for diameters 8″ to 12″, larger sizes will be transported at the east end of the tunnel as the chilled water pipes.

  • Transport in Tunnel and Lifting of Pipes:-
  • Transport.
  • Upon completion of the pipe preparation works, the pipes will be lifted by 2 chain-hoists(fixed to gantries) on to the 2 carriages.
  • The carriages will then be pulled by a forklift into the area of the tunnel as required by the installation team.
  • Lifting of Pipes.
  • The tunnel will be divided in to sectors of approximately 80 to 90m, as the straight lengths of the tunnel allows. In the middle of each sector, a pipe lifting station will be prepared by removing 4 horizontal structural beams. Before removing the beams, at one side of the lifting station, rollers will be installed at a length of approx. 39m in the place where the two chilled water lines will be erected.
  • The pre-insulated pipes will then be lifted by the two scissor lifts to the height of the roller supports and pulled to its final location.
  •  Upon completion of the first side of the sector, the pipes will be lifted slightly up to remove the rollers and to replace them with the sliding support.
  • Then the pipes will be aligned, any difference in height will be adjusted by galvanized steel plates, and then they will be connected by the Victaulic couplings.
  • The same procedure as described above will then be repeated for the second side of the sector for  the lifting and rolling of the pipes, final adjustments however will be done after the two pipes in the middle of the sector are in place and the dismantled beams re-installed.
    • Installation method of  hot water pipe in tunnel.
  • Cut the pipe to 6 meters length and grind the cutting surface of the pipe to a 37½” bevel face outside tunnel for welded pieces.
  • Groove and plain surface the pipes as recommended outside (tunnel entrance.)
  • Start surface preparation out side / in side of pipes by wire brush outside  the tunnel entrance.
  • Before paint can be applied, the prepared pipes will be submitted for a visual inspection or from time to time surveillance.
  • Paint the pipe at the same location of pipe preparation according to painting scheme.
  • The pipes will be loaded by chain hoists to a forklift.
  • Shift the pipe from the tunnel entrance to the lifting area and rolled onto the scissor lift.
  • Lift the pipe above the piping support until it reaches the required level, pull the pipe to the final location .
  • By hydraulic scissor lift the pipe up to sliding support level.
  • Install the sliding supports under the pipe.

Align the pipes by  using galvanized plates between the bottom plates of the sliding supports.

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