| 摘要 |
<p>PURPOSE:To enable easy movement of a circular cylindrical pig while assuring sealability in the stage of repairing the inside surface of an installed pipe by forming said pig into the laminate of the three-layered construction consisting of a hard layer, a fin member for preventing leakage and a soft layer. CONSTITUTION:A rear side pig 1 to be used as a tracive pig is formed by laminating longitudinally plural stages of the three-layered constructions each consisting of a discoid hard rubber layer 1a having the diameter slightly smaller than the inside diameter of an installed pipe A to be inserted therein with the pig, a soft rubber layer 1b similar to said layer and a discoid soft rubber layer 1c having the diameter slightly larger than the inside diameter of the pipe A and to be grasped between both layers 1a and 1b. The peripheries of the layers 1c project to the outside circumference like fins. The laminates are fastened by means of a bolt 9, and nuts 12, 13 and a tractive rope 3 for the same is inserted through the central part of the movable pig 2. A pressure is exerted on the resin between both pigs 1, 2 by the resistance generated when the pigs are in sliding contact with the inside surface of the pipe in the stage of moving the pig in the installed pipe.</p> |
