IS 15679 : 2006 Hot Tapping, Stopple Plugging/Line Plugging of Pressurized Natural Gas Pipelines - Code of Practice

1 Scope

1.1 This Code covers the minimum requirements of materials, equipment andaccessories for hot tapping and stopple plugging/line plugging operationsof onshore natural gas pipelines. It covers the minimum safetyrequirements to be maintained during welding, cutting and plug setting,etc, while carrying out the hot tapping and stopple plugging/line pluggingoperations on pipelines. Checklists have also been included (see Annex A)for the purpose of carrying out inspection, testing of the pipelinesbefore, during and after the operations, in addition to the maintenanceschedule.

1.2 This Code lays down the guidelines and methods for cutting opening into an operating pipeline and connecting branch piping while the line has product under pressure and/or flowing conditions, also for the replacement/modification of a section of pipeline under operation.

1.3 This Code applies where hot tapping is used for gaining safe access to the pipeline contents for delivery to another source, accepting additional product from a new or untapped source, obtaining information on internal pipeline conditions and installation of branch connection, isolation valves, etc, on the line under operation. It is also applicable for isolation of a section of operating line for repair, relocation, addition, modification, etc, without interrupting the flow and creation of a bypass along with installation of pig signal, corrosion probe or coupon, chemical injection point, sampling point and other online devices as required.