Wednesday, September 7, 2011

Procedure for Fabrication, erection and joining of RTRP piping

PROCEDURE
1.         PURPOSE

The purpose of this procedure is to provide the minimum requirements for the fabrication, erection and joining of RTRP piping as per the project specification and manufacturer’s catalogue for

2.        SCOPE

The scope of this procedure applies specifically to project, d covers the bonding process techniques and mechanical key lock jointing of RTRP piping.

3.    REFERENCES


3.9          API 15 LR- Specification for low pressure fiberglass line pipe and fittings.

3.10        RTRP Pipeline Manufacturer’s Recommendations

5.0                

5.1.1       General
              RTRP pipe jointing at site shall be carried out as per the requirements of this procedure and pipe manufacturer’s (vendors) installation and jointing instructions.  The methods of jointing shall be mechanical key-lock jointing of bell and spigot type grooved connection and secondly by adhesive bonding of socket and spigot type connection. Taper adhesive type joints also shall be used, if recommended by the vendor. Mechanical key-lock joints are used for pipe to pipe joining and adhesive joints are for pipe to fittings and fittings to fittings.

5.1.2    Handling, installation, fabrication and inspection at site shall be carried out under the supervision of the manufacturer’s field service engineer qualified to do the job as per CONTRACTOR giving specific requirements for handling RTRP pipes and fittings.

5.1.3    Pipe spool fabricated at Vendor’s fabrication shop and supplied to site shall be checked at site for identification, traceability and damage prior to installation.
5.1.4    As built drawings shall be prepared and submitted to CONTRACTOR after the completion of installation.

5.2           PROCEDURE FOR KEY LOCK MECHNICAL JOINT (vendors assembly      instructions shall be followed).

5.2.1       Material received at site for joining shall consists of

a)    RTRP pipe (Bell one end and spigot other end)
b)   Seal ring (O-ring) appropriate for service condition
c)    Locking Key.
d)   Lubricant supplied by the pipe manufacturer.

5.2.1    Prior to starting of installation, pipe and fittings received at site shall be carefully examined as per CONTRACTOR approved material inspection procedure for any damages on the key, O-ring grooves on pipe ends. To prevent damage to grooved pipe ends, do not drag or slide pipe in any way that abrades or dislodges the end protection.  Pipe may be moved either by hand or by lifting equipment using non-metallic ropes or straps

5.2.2    Once the trench has been prepared and the sand bedding brought to grade and compacted, the pipe sections may be lowered in to place.  Remove enough sand from       the graded bottom at joint locations to maintain a working clearance while assembling the joint.

5.3   Joint Assembly

5.3.1    Preparation of key-lock joining surfaces.

5.3.2    Remove the pipe end protection and clean the groove by a clean dry rag or paint brush and sealing surface of the female end or coupling.  Sand off any projections or rough           edges on the entry ramps, which compress the o-ring during insertion.

5.3.3    Brush or rub a layer of required lubricant into the O-ring groove of the male and inside surfaces of the female end or coupling.  Apply lubricant only when you are ready to complete the joint.  Keep lubricated surfaces clean and free of sand and dirt as contamination is likely to interfere with the joining and sealing.

5.3.4    Lubricate entire surface of the O-ring and slip it in to the first groove on the male end.  Distribute the O-ring evenly in the groove by slipping a screwdriver under it and       sliding the screwdriver around the joint.

5.3.5    Place band clamps on either side of the joint.  Rotate the pipe such that its key holes are in proper position for inserting and driving the key(s).

5.3.6    Align the male end against female end already in place for straight concentric entry.  Proper alignment is essential for jointing.  A joint puller shall be used for assembly.  Connect ratchet winches to pulling rings attached to band clamps on either side of the pipe and ease the joint together.  Place one band clamp just behind female end and other band clamp 4 to 5 ft from the male end.  Tighten winches evenly on the both sides, so that O ring enters smoothly without being pushed out of groove. Check along the pipe to carefully observe concentricity and uniformity of entry.

5.3.7    To drive the keys, place the lubricated locking keys into the insertion holes and slowly close the joint until the key slips into the key way.  Use plastic or wooden mallet to drive the locking key through the insertion holes into the key ways until the leading end can be seen in the insertion hole.  Key should be hammered only so far that it can          be removed as and when required.  Coat the exposed key surface with black acrylic coating or wrap with duct tape.  All key holes to be filled with caulking compound to prevent ingress of sand and dirt.

5.3.8    The joint is now complete and ready for positioning and aligning to fit the trench or hanger support as the case may be.

5.4     PROCEDURE FOR ADHESIVE BONDING OF SPIGOT AND SOCKET JOINT

5.4.1  Bonding requirement

5.4.2       Bonding of joints at site (production) shall be made only in accordance with a Written Bonding Procedure Specification (BPS) which has been qualified in accordance with para A328.2 of ASME B31.3 and manufacturer’s assembly instructions.

5.4.3       Production joints shall be made only by Qualified Bonders who have training or experience in use of applicable BPS and have satisfactorily passed a performance qualification test which is performed in accordance with qualified BPS. The bonders shall be trained and qualified by RTRP pipe vendor.

5.4.4       Each qualified bonder shall be assigned an identification card. All pressure containing bonded joints shall be stenciled or suitably marked with identification symbol of bonder. Stamping is not permitted. Paint or ink, detrimental to piping material shall not be used.
5.5          Bonding Equipment.

5.5.1       Fixture and Tools as recommended by the manufacturer of RTRP piping shall be used for making the joint and specified in approved BPS.

5.6          Bonding Material (Adhesive)

5.6.1       Bonding material used shall be of type and quality specified and supplied by the pipe manufacturer and as used for BPS qualification test.

5.6.2       Bonding material that have deteriorated by exposure to air or prolonged storage or will not spread smoothly, shall not be used in making bonding.  Adhesive shall be stored at temperature recommended by manufacturer.

5.6.3       Adhesive kit shelf life shall not exceed manufacturer recommendation. 

5.6.4       All material test certificates received from manufacturer shall be produced for review of CONTRACTOR inspector prior to their use if required.

5.7          Weather Condition.

5.7.1       In case of rain, wind or dust storm proper protection for the parts to be bonded and for bonders shall be provided so as to ensure correct performance of the work. Otherwise no bonding shall be permitted.

5.8          Preparation for Bonding

5.8.1       All cutting of pipe shall be carried out as per pipe manufacturers assy. instructions.

5.8.2       Pipe spools shall be shop fabricated using adhesive type of joint or integral fittings.

5.8.3       An individual joint identification number shall be given and marked with a marker on the pipe surface adjacent to the joint, prior to commencement of bonding. Stamping shall not be used. A joint numbering system shall be established during the planning of the bonding by the Quality control department.

5.9          Bonded joint Quality

5.9.1       All bonding shall be performed in a workmanlike manner, using the correct tools and equipment with adequate and competent supervision at all times. The bonding parameters shall be substantially the same as those included in the procedure qualification.

5.10        Repair of Bonding Defects

5.10.1     Defective joints and other workmanship that fail to meet requirement of ASME B 31.3, shall be repaired and the new work shall be re examined, by the same means, to the same extent as required for original work. Repair shall be carried out as per the pipe manufacturer’s repair procedure.
6.0          Attachments
6.1          Attachment No.1         - RTRP Piping Inspection Record
6.2          Attachment No.2                   - Bonding procedure specification
6.3           Attachment No.3                  - Bonding Procedure Qualification record
6.4          Attachment No.4                   - Bonder’s qualification certificate             
6.5          Attachment No.5                   - Daily Bonding inspection report

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