| 摘要 |
<p>A steel service pipe (12) is connected to a main (10) by a tee (14). A flexible assembly (18) is inserted through the open end of the pipe (12) and through the tee (14) into the main (10). The flexible assembly includes a section of lower stiffness (22) and a ball and socket connection (24) of even lower stiffness at its leading end. The ball (30) is connected to a weight (34). The weight (34) falls down on entering the tee and creates a turning moment on the assembly (18). A plastic pipe (60) is inserted through the open end of the pipe (12) over the assembly (18) and is inserted through the tee (14) into the main (10). The pipe (60) has a corrugated leading end (64) which is more flexible than the remainder of the pipe (60) and has a tapered nose (64) terminating in a cylindrical mouth (66) which enters an aperture (70) in a liner (72) in the main (10).</p> |
