AWWA C217:2004 pdf download.Petrolatum and Petroleum Wax Tape Coatings for the Exterior of Connections and Fittings for Steel Water Pipelines
4.4.1 Protection during welding. An 18-in. (450-mm) wide strip of heat- resistant material shall be draped over the coated pipe on each side of the weld area during welding to avoid damage to the coating by hot weld spatter. No welding ground shall be made on the coated part of the pipe. 4.4.2 Hoisting. Coated pipes shall be hoisted from the trench side into the trench using wide belt slings. Chains, cables, tongs, or other equipment likely to cause damage to the tape coating shall not be used; nor shall dragging be permitted. The tape coating shall be inspected on the underside of the coated pipe while the pipes are suspended from the slings. Any tape coating damage shall be repaired according to Sec. 4.3.4.
4.4.3 Bedding and trench backfill. Trenches shall be backfilled in a way that prevents abrasion or other damage to the tape coating. Unless otherwise specified, the following requirements shall be met. Where the trench traverses rocky ground containing hard objects that could penetrate the protective coating, the pipe shall be bedded on a 6-in. (150-mm) thick (minimum) layer of screened earth or sand. Other acceptable bedding material may be used in place of the earth or sand.
Backfill shall be placed around the exterior of the coated pipe only after the final inspection has been made and the exterior coating has been approved. If rocks or other hard objects occur in the backfill material along any section of the pipeline, screened backfill material shall be placed around the coated pipe to a minimum depth of 6 in. (150 mm) above the pipe before backfilling the remainder of the trench. Bedding and backfill shall be compacted in the trench according to the purchaser’s specification. Rodding with metal rods or other metal tools that could come into contact with and damage the tape coating shall not be permitted.AWWA C217 pdf download.