| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent generation of traffic obstruction and residual earth by projectingly providing a housing part for a cutting piece in the position facing a cylindrical body through a process of projectingly providing the cylindrical body to which a punching hole saw can be mounted on a split sleeve for constituting an airtightness cylindrical part for covering a pipe subjected to supply. SOLUTION: A split sleeve is mounted by connecting a first member 3a on which a cylindrical body 5 to which a punching hole saw 5 can be mounted is projectingly provided and a second member 3b on which a housing part 6 for a cutting piece is projectingly provided to each other across a cutting estimated part of a pipe subjected to supply 2, the cutting estimated part of the pipe subjected to supply is connected with an airtightness cylindrical part, and the punching hole saw 4 whose punching diameter is set to the diameter larger than the outside diameter of the pipe subjected to supply is mounted on the cylindrical body, and cutting of the pipe subjected to supply is performed in the split sleeve. Gas is stopped by inserting a stopper body of a gas cutoff device from the cylindrical body to the upstream side of the pipe subjected to supply as well as detachment of the punching hole saw is performed by using an airtightness bag. After that, the split sleeve is detached, a new gas pipe is connected to the cutting end of the pipe subjected to supply by a mechanical joint, the stopper body is detached, and piping work is performed.</p> |
