| 摘要 |
<p>PROBLEM TO BE SOLVED: To put a rope for traction which is connected to a pig main body into a tube to prevent the increase of the moving resistance of the pig main body. SOLUTION: In the pig in which the pig main body 1 moving in the tube is connected to one end side of the rope 2 for traction, the rope 2 for traction is housed inside the pig main body to be freely fed to the outside of the pig main body, the rope 2 for traction is housed by a required length inside the pig main body 1 to be freely loaded and a winding instrument for winding the rope 2 for traction to be freely fed to the outside of the pig main body 1 is provided inside the pig main body 1.</p> |
