Copyright Goodheart-Willcox Co., Inc. Chapter 21 DWV Pipe and Fitting Installation 333 21.7 Installing Cast-Iron Pipe The correct allowances for the depth of the hub on com- mon sizes of hub and spigot cast-iron pipe are given in Figure 21-45. This allowance must be included when measuring pipe length. 21.7.1 Cutting Cast-Iron Pipe Cast-iron pipe is generally cut with a compound lever or hydraulic pipe cutter, Figure 21-46. This tool squeezes the chain tightly around the pipe. Small cut- ters in the chain bite into the pipe until it fractures. 21.7.2 Trial Assembly and Marking Cast-Iron Pipe Check the fit of all the pipe and fittings that have not been assembled. If the pipe and fitting are to be assem- bled with adhesives, mark the final position of each of the fittings relative to the pipe so they can be reas- sembled in the proper position. See Figure 21-10. A felt marker in a contrasting color to the pipe and fittings works well for this purpose. The Ridge Tool Co. Figure 21-40. A die and die stock are used when a pipe is threaded by hand. Die stock holds interchangeable dies. Sleeve guides pipe into die Pipe Incomplete threads Goodheart-Willcox Publisher Figure 21-41. Cutaway shows pipe being guided squarely into die. A B The Ridge Tool Co. Figure 21-42. Two types of power driven threading machines. A—Portable threader. B—Bench-mounted threading machine. Goodheart-Willcox Publisher Figure 21-43. Teflon tape can be applied to seal threaded joints. Goodheart-Willcox Publisher Figure 21-44. Fittings are securely tightened with a pipe wrench. Allowances for Hub Depth Pipe size (in) Engagement (in) 2 3 4 2 1/2 2 3/4 3 5 6 8 3 3 3 1/2 Goodheart-Willcox Publisher Figure 21-45. Add the appropriate allowances to the face-to- face measurements of cast-iron pipe.