Below plumbing method statement describes the procedure for the installation of copper pipe for domestic water services (hot & cold) inside buildings for any kind of the building construction project.
Overall project manager is responsible for the implementation of this copper pipe installation method statement.
By following this MOS project team will ensure that plumbing installation works are done on accordance with project specifications, applicable standards and approved material submittals.
Necessary Tools and equipment:
Below is list of necessary tools and equipment for the the installation of copper piping:
- Hand tools used for cutting the Pipes
- Hand pump and pressure test set
- Standard mechanical Tool Box
- Measuring Equipment
- Sprit Levels
- Hand Gloves
- Hand pump & Pressure Gauge for Pressure Test
- Brazing set for jointing of pipes
HSE Requirements
Adequate safe access to the installation area shall be provided.
Risk assessment for domestic water piping installation will be prepared and submitted for approval.
Workmen shall wear all appropriate safety personnel protective equipment such as helmet, coverall clothing, safety shoes, goggles & gloves, wherever required.
If work is at high level, only approved scaffolding and safety harness/ belts shall be used.
Sequence of Work
Store all pipes in proper storage conditions, which are free from dust, direct sunlight and extreme temperatures.
For long-term storage, stack the pipes in racks with adequate spacing and supports, place larger diameter pipes at the bottom of the stacks.
While handling the pipes, take extreme care to avoid contact of pipes with sharp corners/edges such as loose nail heads, sharp metal surfaces etc.
This may cause damage to pipes or removal of coatings (if any) by rubbing against the sharp edges during transit.
All open ends of the pipes shall be plugged with end caps or wrapped with polyethylene sheets to prevent entry of dust & other foreign particles.
Checks before Copper Pipe Installation
Piping materials, fittings, supports & hangers etc. used for water supply pipe installations shall be in conformance to specifications and material approvals.
Water supply pipes (hot & cold) above the ground within the buildings shall be copper tube conforming to EN1057, (formerly BS 2871) part 1, Table X.
Copper pipes embedded in walls shall be copper tube with green color insulation conforming to EN1057, (formerly BS 2871) part 1, Table Y.
Copper pipe fittings shall conform to EN1254 (formerly BS 864 part 2)
Both Hot water supply & return pipes are insulated with preformed sections of glass fibers bonded with a heat resistant resin together with Glass reinforced Aluminium foil.
Density is 64kg/m3 for insulation (25 mm) of pipes inside buildings.
Ensure the pipes are free from dust and damages prior to installing.
Location of pipe sleeves and possible routing obstructions are checked prior to the installation of pipes.
Ensure marking of pipe routing and supports on the ceiling are clearly visible and done as per approved drawings.
Copper Pipe Installation Method
Make sure that the pipe routing is as shown on shop drawings.
Install all pipe supports and clamps as per manufacturer recommendations.
Installation of all supports shall be in accordance with approved supporting detail drawings.
Where steel plates forms part of the ceiling, the suspension rods are connected to stud welded rods (which are already stud welded to the steel plates) using threaded connectors.
Arrange the supports as near as possible to joints & changes in direction.
Vertical rising pipes particularly in shafts shall be adequately supported at the base to withstand the total weight of the riser.
Seismic supports for the pipes are provided, wherever required.
All copper pipe work shall be erected to present a neat and orderly appearance, arranged to or at right angles to the structural members of the building, giving maximum head room and shall not obstruct windows or door ways.
All copper tube surfaces & inside of fitting socket is neatly cleaned before installation.
Ensure the ends of the copper tube are cut square and remove any burrs from the inside or outside.
Jointing of copper pipes & fittings of sizes 15 mm to 42 mm is made by Soldering, while pipes of diameter larger than 54 mm is joined by Brazing the copper pipe.
Copper Pipe Soldering Method
The inside of the fitting socket and the outside of the tube is cleaned with a cleaning pad, fine sand paper or steel wool.
Using a brush, an adequate but not excessive amount of flux is applied to the outside of the tube and the inside of the fitting socket.
The tube is inserted to the fitting until it reaches the tube stop. Excess flux is wiped off.
The assembly joint is heated evenly on all sides using fuel torch.
Care must be taken to ensure that the tube and fittings are properly supported with a reasonable, uniform capillary space around the entire circumference of the joint.
When the correct temperature is reached, solder (lead free) is applied to the mouth of the fitting and the melted solder will flow freely and be drawn into the joint by capillary action.
Briefly reapply the fuel torch and wipe off excess solder.
The joint is then allowed to cool without disturbance and cleaned generally.
Copper Pipe Brazing Method
All Copper Pipes & fittings above 52mm diameter shall be jointed using the copper brazing technique.
The pipe and fitting is assembled as normal.
Method of application of flux is similar to that of soldering. Filler rod with silver content is used for brazing.
The joint shall be heated quickly and evenly on all sides to approximately 700/750o C red heat in poor daylight.
An oxy-propane, oxy-acetylene or other suitable torch is used with a large soft, neutral or slightly reducing flame. This is kept moving through out the making of the joint to avoid excessive local heating.
The filler rod is then applied to the space between the tube and the fitting, allowing the brazing alloy to melt and flow into the annular gap.
The gap between the socket and tube is filled with the filler alloy leaving a small, uniform bead of brazing alloy around the mouth of the socket.
Allow the joint to cool without disturbance and clean generally.
For copper pipes (Table Y) embedded in walls the joints & elbows shall be covered with wrapping tape.
All open ends of pipes which are left as the work progresses, shall be temporarily closed with polythene sheet, plastic caps or metal flanges, as required.
Adequate clearance shall be provided between insulated pipe work running together and between walls and floors.
Domestic Water Piping Accessories Installation
All domestic water copper piping accessories i.e. valves, air vents, water hammer arrestors and pressure gauges shall be installed as per manufacturer recommendations.
Location of all above mentioned accessories shall be as indicated on approved shop drawings and shall be in accessible locations/positions.
Flexible joints with bronze couplers shall be provided for the copper pipes at the expansion joints, as shown on the approved shop drawings.
Copper Pipe Insulation Procedure
All Hot water supply & return pipes are insulated with Aluminium foil faced preformed sectional fiberglass insulation. The Insulation thickness shall be 25mm (density 64kg/m3)
Copper Pipe Testing Procedure
All copper piping system shall be tested to a pressure equivalent to 1.5 times the maximum working pressure.
The indicated pressure shall be maintained for the required holding period without further application of pressure and without visible leakage or a drop in the indicated pressure.
All pipe installations shall be inspected in accordance to the Inspection test plan & checklists.
Tests shall be performed on isolated portions of piping in order to facilitate general progress of construction.
Any modification made in the Piping system after a successful test shall call for re-testing of the affected portion of the piping system.
Results of Inspection & testing shall be recorded on the inspection checklist forms.
References and Attachments
- Shop Drawings
- Material Approvals
- Risk Assessment
- Inspection & Test Plan ITP
- Installation Inspection Checklist
- Checklists for Testing