Method of Statement For Drainage Piping Installation (Under &Above Ground Sanitary Ans Drainage Lines)..

TABLE OF CONTENTS

1.        Purpose………………………………………………………………………………….Page No

2.        Scope……………………………………………………………………………………Page No

3        References.................................................................................................................Page No

4.         Material…………………………………………………………………………………Page No

5.        Procedure……………………………………………………………………………..…Page No

6.        Safety…………………………………………………………………………………....Page No 

7.         Responsibilities………………………………………………………………………….Page No 

8.        Attachment………………………………………………………………………………Page No

         * Gravity Test Format

         * SATIP AND SAIC 

         * JSA (Job Safety Analysis)

  

      
1.             Purpose

·         The purpose of this method statement is to set guidelines and methodology to be followed during installation of upvc pipes underground and above ground and testing for drainege and sanitary line system.

2.            Scope

·         This scope of this procedure is to standardize method of statement details the method for installation and hydrostatic gravity testing of underground drainage piping works. Hence, execution of the work shall be done as per acceptable standards and specifications.

3.            References

·         SAES-A-004 (General Requirements for Pressure Testing)

·         SAES-S-010 (Sanitary Sewers)

·         SAES-S-060 (Saudi Aramco Plumbing Code)

4.      Material

·                    UPVC Pipes and Fittings, Solvent Cement Glue

5.           Procedure

·         Storage

a.)   For Material receiving, storing and handling visual and mechanical inspection must be done. Any damage and discrepancies must be recorded and reported.

b.)   Checked and inspected material must comply with specification requirements and shall conform with the Purchase Order.

c.)   Pipe shall be given added protection when storing on a flat surface free from sharp objects.

d.)   Storing of pipe shall not be exposed on direct sunlight.

e.)   Tags and appropriate marking for pipes must be installed for identification.

·         Trench Preparation for Underground

a.)   Trench excavation must be installed depending on the pipe size, type of ground and depth required.

b.)   Bedding for pipes shall be constructed by spreading and compacting. Only approved bedding material shall be used for bedding of pipes. After pipe have been installed, additional material be placed (if required) and compacted equally on each side of the pipe, this shall be done in sequence practicably.

c.)   Pipes are required to be bedded directly on the trench bottom, the final excavated surface shall be trimmed and leveled to provide even bedding for the pipeline and shall be free from all foreign matter that may damage the pipe. When rock is encountered, the trench shall be cut at least 150 deeper than the ground and made up with well compacted selected fill material.

·         Pipe Laying and Installation

a.)   All pipe are laid with due regard to the fall and invert levels set out in the shop drawing.

b.)   Pipe requiring socket joints are required to be installed directly on a trench bottom, on gradual/sand bed, joint holes/spaces shall be formed in the bedding material or final excavated surface to ensure that each pipe is smoothly and uniformly supported throughout its length.

c.)   Pipe and fittings shall be examined for damage and joint surfaces and components shall be cleaned immediately before laying.

d.)   No protective cap, disc or other appliance on the end of a pipe or fitting shall be removed permanently until the pipe or fitting which it protects is about to be jointed.

e.)   Suitable measure shall be taken to prevent soil or other material from entering pipes and to anchor each pipe to prevent flotation or other movement before works are complete.

·         Solvent Weld Joint

Pipe sizes 2000mm and below are joined together by the solvent weld method. Only approved solvent and glue shall be used. The MSDS must be attached for handling and using these materials. A job safety analysis must be prepared for handling of this hazardous material.

a.)   Using cleaning fluid, both surfaces to be joined must be cleaned. Surface must be free from dirt and machine release agents and softens the surface ready for weld.

b.)   The solvent cement shall applied evenly over the mating surfaces of both pipe and socket weld.

c.)   Pipe shall be inserted to the socket with a slight twisting action to full socket depth. Removed surplus cement using cloth.

d.)   Joint shall be firm enough to handle in 5 minutes.

e.)   All open ends of pipe must be cover with end caps or wrapped with polyethylene sheets to prevent entry of dust and other foreign object.

·         Backfilling

a.)   Pipe surround

After pipe laying, Inspection and testing a further 3oomm of approved bedding material shall be used for pipe surround, compacted with hand from all sides while tamping lightly over the crown. The bedding material shall span the entire width of the trench and shall be laid in not more 150mm deep layers, each layer being compacted by hand.

b.)  Main Backfill

This is usually compacted infill with the original trench soil over the layer of pipe surround. Heavy mechanical rammers shall not be used until the fill has reached a sufficient height above the top of the pipe.

c.)   Above Ground Drainage Pipes

a.)   All .pipe work shall be adequately supported in such manner as to permit free movement due to expansion, contraction and vibration or other changes in the system.

b.)   All above drainage pipes are joined using either Push-fit or solvent method.

c.)   Supporting of pipes shall be arranged as near as possible to joints and changes in direction. For supporting of pipes, galvanized steel split clamps shall be used.

d.)   All vertical pipes (160mm dia. And below) shall supported using split clamps  screwed to the wall  using threaded rods, diameters of  which shall according to the clamps  manufacturer recommendations.

e.)   Where soil and vent pipe are suspended from the underside of the slab, they shall be held rigid position. Based on the pipe diameters, single or double iron supports shall be used as required.

f.)    Pipe supports shall be provided at intervals as per specification and/or BS Standard.

d.)  Hydrostatic Gravity Head Testing

a.)   Water test is conducted to ensure and prove the tightness of the joints and ensure there are no leaks in the piping system.

b.)   Medium of fluid shall be potable water, well water or raw water.

c.)   The pipe shall be support a water head of 1.2 m at its upper end and not more than 2.4 m at its lower end for the period of four hours or as specified.

d.)   The water shall be kept in the system or in the portion under test for at least 30 minutes before inspection starts. While the system is under pressure, a careful inspection shall be made on all pipes and joints. If any leak in joints or evidence of defective pipe or fittings is revealed, the defective pipe/fitting should be immediately replaced with new joints and materials.

e.)   Make sure that all open stub-up are properly plugged-off with test plug and properly vented.

f.)    After correction is made, the test pressure will be maintained for minimum 30 minutes and witnessed by contractor QA/QC.

g.)   Testing will be inspected by main contractor/consultant to their satisfaction and the test results are recorded in the inspection report by getting approval in test certificate which will maintained with the QC documentation for records.

h.)   Drain water after approval by the consultant and make sure water is disposed and discharged in a remote location. After the testing backfilling of trench will be allowed.

6.              Safety

·         Protection and safety shall be in accordance with the approved Safety Procedure. All labors shall be equipped with safety shoes, helmet, safety glass, gloves, ear protection, protective clothing and face shield against any injuries from the work.

·         Extra care shall be taken during cutting and shaving of pipe ends.

·         Sign board must be placed when hydrostatic gravity test is in progress.

·         Permits shall be obtained prior to start of job.

·         Barricade is a must when testing.

7.    Responsibilities

·         Site Engineer has to ensure that the site QC section is provided by the necessary facilities and cooperation from all supervisors, foremen and laborers to enable satisfactory inspection and verification performed by the building section.

·         The safety manager has to ensure that all safety requirements will be enforce by manners to prevent injury to personnel. He should provide written instruction to established working method; explain the sequence of the operation, outline the potential hazards at each stage and indicate precaution to be adopted.

·         The mechanical engineer/plumbing supervisors are the solely responsible for works being implemented are in conformance with specifications.

8.    Attachment

·         Gravity Test Format

·         SATIP and SAIC.

     SATIP-S-010-01 Gravity Sanitary Sewer Pipe and Manhole.

     SATIP-S-030-01 Strom Water Drainage System.

     SATIP-S-060-05 Roof Drain and Drainage Pipe.

     SATIP-S-060-06 Building DWV Pipe.

     SATIP-S-070-01 Gravity Sanitary Sewer Pipe and Manhole.

     SATIP-S-060-02 Thermoplastic and RTR Pipe.

     SAIC-S-4038 Roof Drain Installation Inspection.

     SAIC-S-4039 Roof Drain Receiving and Storage.

     SAIC-S-4040 Drainage System Layout.

     SAIC-S-4043 Indirect Waste Piping Installation.

     SAIC-S-4054 RTR & Thermoplastic Pipe Installer Qualification.

     SAIC-S-4055 RTR & Thermoplastic Pipe Receiving (Pressure and Sewer Pipe).

     SAIC-S-4056 RTR & Thermoplastic Pipe Handling, Storage and Preservation.

     SAIC-S-4057 Assembly of Thermoplastic (PVC. UPVC, CPVC and HDPE) Piping.

     SAIC-S-4060 Strom Water Drainage System  Installation.

·         JSA Gravity (Job Safety Analysis)