procedure for wrapping & coating rev2

4
2 (Unit 1 & 2)

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Page 1: Procedure for Wrapping & Coating Rev2

2

(Unit 1 & 2)

Page 2: Procedure for Wrapping & Coating Rev2

2(Unit 1 & 2)

Page 3: Procedure for Wrapping & Coating Rev2

1. Before adhering the tape to the pipe, it is suggested to gently heat the primed pipe by a run of LPG Torch2.Overlap should be a minimum of 12.5 mm

Voltage to be applied shall be as per holiday test equipment manufacturer’s recommendation (standard practice is 5KV per mm if coating thickness)

IS 10221 :2008

IS 10221 :2008

* Storage - a) Coating primerb) Self adhesive anti corrosion tape

2

(UNIT 1 & 2)

Storage and handling of the wrapping and coating material (raw) are determines the effectiveness, if there is any discrepancy found than same should be rejected.

Two points added (1.00.00 & 2.00.00)

* Materials - All types of coal tar wrapping tape to be used as per approved list of Reliance.

2.02.00 Pipe Coat Wrapping* The tape rolls to be taken out of the packing boxes and leave in the sun for at least 30 min before application. The tape can be hot applied usinga suitable and compatible primer.* The tape is slightly warmed on the side containing more coating compound with either a blow lamp or a gas flame to soften the coatingcompound. Care shall however be taken to ensure that the compound does not melt. The tape shall then be applied. The adhesion test shall becarried out only after minimum 72 h of curing time.* If the tape is being applied in cold weather, the surface of the pipe shall be preheated until it is warm to the touch and the traces of moisture arealso removed

Page 4: Procedure for Wrapping & Coating Rev2

IS 10221 :2008

6.0 Reference Standard IS 10221 : 2008, IS 15337 :2003

7.0 Record Wrapping and Coating Inspection Report.

9.0 In case of any conflict between this procedure and Contract Specification requirements, the later shall govern.

VI) Tape Coating of Weld Joints

* The tape is applied over the weld joints after the necessary welding and testing of the joints are completed. * The procedure for application of tape shall be same as bare pipe procedure. * Overlaps on each side of the weld joints of pipe ends shall be 50 mm

8.0 Handling, Transportation And Storage of Coated Pipes

8.0 (Details)8.1 During the storage and handling of the coated pipe determines the effectiveness of the coating, there is any discrepancy found that same should be rectified with standard procedure.8.2 Coated pipes loading, unloading, handling, transportation and storage by using suitable means to avoid damage to the pipe and coating.8.3 Coated pipes may be handled by means of slings of belts of proper width (minimum 60 mm) made of nonabrasive/non-metallic materials. 8.4 The pipes shall be stacked completely clear from the ground at least 300 mm so that bottom row of pipes remain free from any surface water. 8.5 The pipes shall be stacked at a slope so that draining rain does not collect inside the pipe.8.6 The lorries used for transportation shall be equipped with adequate pipe supports having as many round hollow beds as there are pipes to be placed on the bottom of the lorry bed. Total width of supports shall beat least 5 percent of the pipe length and minimum 3 in number support shall be provided.