| 摘要 |
<p>PURPOSE:To enhance the easiness in execution of works by connecting a crushing device and a new buried pipe draw-in rod at the tip of a rod pipe inserted through an existing buried pipe, and then pulling it back to the starting pit side. CONSTITUTION:A rod pipe 20 is inserted into an existing buried steel pipe 21 through a root push device 19 until the tip reaches a reach pit 18. A buried steel pipe crushing/new pipe draw-in device 22 is fixed to the tip of the rod 20, followed by pulling back to the starting pit 17 side, and the steel pipe 21 is crushed into slit form by a rotary cutting edge of the device 22. A new rod pipe 20a and a pilot pipe 23 are connected with the device 22 and laid in the pipe 20 and part around it. If the device 22 is twisted, the twisting is sensed, and the reactive force is adjusted by a hydraulic cylinder, etc., for making correction. The pipes 20a, 23 are fitted with a single pipe draw-in device and a lump draw-in device, and there a new buried pipeline is connected, drawn in, and laid. This enables easy execution of works for a long distance division and greatly enhances the reliability and economics.</p> |
