Specifications Part 1 - Water Supply, Sewerage and Tube Well Works

11.4.8.3 The taper pipes and half section tapers channels may be in any normalcombination of diameter and lengths.11.5 Loading and UnloadingAt every point of loading or unloading, pipes or casting must be handled byapproved lifting tackles. Unloading by rolling down planks or any other form ofinclined ramp will not be allowed unless the written consent of the engineer tothe method proposed has been obtained. Pipes are to be carefully stacked onsite with timber packing under and between the pipes. The pipes are to be laidup at the gradients beginning at the lower end. No pipe is to be laid until thetrench has been excavated to its required depth for a distance of 20m, in frontof the pipe to be laid. (this distance may very as directed by the Engineer.11.6. Laying11.6.1 Handling of Stoneware pipes into Trench in shallow trenches manual handlingis enough, but in deep trenches they should be lowered into the trench bymeans of ropes. Under no circumstances shall the pipes be dropped ordumped into the trench.11.6.2 Detection of Cracks in pipes and fittings: The pipe and fittings shall beinspected for defects, and be rung with a light hammer preferably whilesuspended to detect cracks.11.6.3 Cleaning pipes and fittings: All lumps, blisters and excess coating material shallbe removed gently from the socket and spigot end of each pipe and the outsideof the spigot and the inside of the socket shall be wiped clean and dry beforethe pipe is laid.11.6.4 Placing the pipes in Trench: Every precaution shall be taken to prevent foreignmaterials from entering the pipes when it is being placed in the line. Normallythe socket ends should face the up-stream. When the line runs uphill thesocket ends should face the up-grade.11.6.5 After placing a length of pipe in the trench on concrete bedding where that isspecified, the spigot end shall be centered in the socket and the pipe forcedhome and aligned to gradient. The pipe shall be secured in place withapproved backfill material or concrete tamped under it except at the socket.Pipe and fittings which do not allow a sufficient and uniform space for jointsshall be removed and replaced with pipe and fittings of proper dimensions toensure such uniform space. Precautions shall be taken to prevent dirt fromentering the joint space (see Drawing No.-8).11.6.6 At time when pipe laying is not in progress, the open ends of pipe shall beclosed by a watertight plug or canvas or other means approved by the siteengineer.11.6.7 Sight rails shall be provided at all changes of directions or gradients atdistances of about 30 m along straight lengths. The centre line shall be markedUrban Administration & Development Department Page 131