Method Statement for Chilled Water Pipes

METHOD STATEMENT FOR INSTALLATION OF CHILLED WATER PIPES: 1.0

SCOPE AND PURPOSE

1.1

This "Method Statement" covers the nature and type of work for the installation of Chilled Water Piping and Accessories in the building and the frequency of which the inspections are to be carried out.

1.2

This procedure also covers the method of installation and inspection of Chilled Water Piping with Accessories.

2.0

WORK SEQUENCE AND METHODOLOGY

2.1

All the materials delivered to site are inspected properly and stored as per the manufacturer recommendations.

2.2

Request for Inspection shall be issued Consultant's approval.

2.3

Work shall be carried out by the site staff under the strict supervision and guidance of the concerned Supervisors / Engineers.

2.4

Site Engineer shall check as per the checklist attached, shall further checked by the Consultant.

2.5

Request for Inspection shall be prepared by Site Engineer for inspection with Consultant.

3.0

PLANT

3.1

Following indicative hand tools list shall be used for the installation works. Drilling Machine Hammer Sprit Level Pipe Wrench Grooving Machine Thread Cutting Machine Pipe work Tools box

4.0

SAFETY

4.1

Only trained persons shall operate the power tools.

4.2

Ensure all concerned personals shall use PPE and all other items as required.

4.3

Ensure adequate lighting is provided in the working area.

4.4

Ensure deep manhole excavations / shaft openings are protected with barricade, tape, safety nets.

4.5

Refer Risk Assessment record

5.0

METHODS

5.1

All the materials delivered to site shall be inspected and stored properly as per the manufacturer recommendations.

5.2

Work shall be carried out by the site staff under the strict supervision and guidance of the concerned Supervisors / Engineers.

5.3

Site Engineer shall check the installations as per the approved inspection test plan.

5.4

Request for inspection shall be prepared by Site Engineer and shall be issued to Consultant for further inspection.

6.0

INSTALLATION OF CHILLED WATER PIPING

6.1

Fix the sleeves as per approved shop drawings and specification, during the construction of structural elements.

6.2

Ensure All chilled water pipes shall be painted with two coats of red oxide primer prior to application of insulation.

6.3

Piping connection 2” (inch) and below shall be made by threaded joints and piping connection 2-1/2 inch and above are made by Grooved Joints.

6.4

The piping grooves shall be done by using grooving machine and depth and width of a groove shall be maintained as per Groove fitting manufacturer recommendations.

6.5

Mark the location of piping as per specification and approved shop drawing.

6.6

Install approved supports, brackets for piping as per specification, approved shop drawings and site requirements for each individual case (ie. Slab, Wall etc.).

6.7

Supports shall be installed as per pipe manufacturer’s recommendations.

6.8

Readymade hardwood shall be used for supporting the vertical chilled water piping, which is placed on galvanized L angle or U channels and fastened with GI threaded rods.

6.9

Roller supports shall be installed for the pipes 200mm and above and in the expansion joints.

6.10

Flexible Pipe connectors shall be installed in all Expansion Joints and Equipment piping connections.

6.11

Pipes shall be laid with gradient as per approved shop drawings and site conditions.

6.12

All the open ends of the pipes shall be protected properly at the end of each day’s work.

6.13

Drains shall be installed at low points in mains and branch lines consisting of gate valve and short threaded nipple and cap so that the system shall be drained completely.

6.14

Valves, Piping specialties and accessories shall be installed as per manufacturer recommendation and approved shop drawings.

6.15

Unions shall be provided in direction of flow after valves for sizes 2” and below & 21/2” and above flange connection shall be provided.

6.16

All valves shall be installed suitably to permit easy access for future maintenance.

6.17

Eccentric reducers shall be installed in Horizontal chilled water system & concentric reducers shall be installed in vertical chilled water system.

6.18

Automatic Air vents shall be installed at high points and where ever required in order to trap air from the chilled water system.

6.19

Condensate drain piping shall be connected to the equipment drain pan connections as per approved shop drawings.

6.20

Condensate drain piping will be extended to the nearest floor drain and connected to the drain system.

6.21

Plug all open ends of pipes at the end of each day’s work using end caps.

6.22

Raise Request for Inspection of Installation of Chilled Water Piping and fittings including supports / brackets, valves, piping specialties and accessories as per the approved shop drawing, by Consultant

6.23

After approval of installation of pipes and fittings, flushing shall be done for chilled water Pipes with clean water to remove dust and debris that might have been present during construction work.

6.24

Plug all connections / branches / drains and fill with clean water for hydro testing.

8.0

TESTING OF CHILLED WATER PIPES & FITTINGS

8.1

Care shall be taken to all the equipments, apparatus, devices to a pressure exceeding its prescribed test pressure as obtained from its name plate data or product catalogues.

8.2

Care shall be taken to Equipments, apparatus and devices that might be damaged by the test pressure shall be removed or blanked off.

8.3

Ensure All Valves are in open condition before starting pressure test, NO pressure shall be applied against closed valves.

8.4

Ensure Temporary blank flanges are anchored firmly in a way to accommodate all developed end trust.

8.5

The Piping system shall be tested closed by plugging all openings in the system in a proper way and filled slowly with water.

8.6

Ensure all system is free from air lock, if so all the vent all entrapped air from the system.

8.7

Ensure water is reached to the entire system by releasing plugs temporarily.

8.8

Pressure shall be applied to the system by means of hand pump drawing from a water container. The pump discharge shall be connected to the system through a globe valve, check valve and calibrated pressure gauge of suitable range to have the test pressure range in the middle of the range.

8.9

Subject the Cold Water piping to hydro test at 10 Bar Pressure for 24 hours.

8.10

Ensure Test pressure is same at highest point of the system.

8.11

Repair the leaks and defects if any until satisfactory results are obtained.

8.12

Raise Request for Inspection of hydro testing to witness the same, by Consultant.

8.13

After approval of inspection of hydro testing, release the water gradually and protect the piping installation, and end cap the pipe.

9.0

INSULATION OF CHILLED WATER PIPING

9.1

Check all required approved chilled water pipe insulations materials are readily available on site.

9.2

Approved 25mm thick closed cell rubber insulation pipe sections shall be used for up to 40mm diameter chilled water piping and 32mm thick for 50mm and above diameter chilled water pipes which installed inside the building.

9.3

Mock-up for pipe insulation shall be provided for consultant review and approval.

9.4

Apply the approved insulation materials and accessories according to specification and manufacturer instructions.

9.5

Ensure all insulation materials are in dry condition during the application.

9.6

Pipe surface shall be cleaned properly and painted as per specification.

9.7

Apply insulation with longitudinal seams at top and horizontal pipe runs.

9.8

Pipe insulation shall be applied with least number of joints.

9.9

Approved adhesive (Ideal 81-10) shall be applied in longitudinal seam and end faces of the insulation and entire pipe surfaces.

9.10

For flanges, elbows, fittings and valves mitered section of pipe insulation of same material shall be used.

9.11

Permissible access shall be maintained to the valves to operate without disturbing the insulation.

9.12

Removable type insulation sections shall be prepared and provided to valves including check valves and strainer basket and other valves.

9.13

In case of rising steam valves used in chilled water system, insulation shall be extended and insulation joints and valve specialties seams shall be sealed properly in order to prevent passage of air to pipe surface.

9.14

Aluminium tape of 75mm width shall be applied on the joints of insulation segments properly.

9.15

Pipe penetrations through roof, exterior wall, interior wall, fire rated wall, floor etc., through sleeves shall be closed by ram packed with loose fiber glass insulation and sealed with approved mastic and for fire rated walls approved fire proof sealant shall be.

9.16

Use Thermo foil recommended Tape to seal the joints in a way no air can penetrate through the joints

9.17

Raise request for inspection of Insulation of Chilled Water Piping, by consultant.

9.18

Identification for Chilled Water Supply and return line and valves and specialties shall be done as per specification with approved identification materials.

9.19

Raise request for inspection of Identification of Chilled Water Piping and Accessories, by Consultant.

10

INSPECTION

10.1

A notification of Inspection of installation Chilled Water Piping with all Accessories shall be submitted one day prior to the Engineer through a inspection request.

10.2

All Inspection stages shall be followed respective to Inspection Test Plan