| 摘要 |
<p>The inventive device ( wad hereafter) is made of elastic, flexible, airproof and waterproof, solid, integral or composite solid material, in particular of foamed polyethylene, and has a cylindrical shape provided with grooves and slots on the surface thereof or is devoid thereof. The inventive wad cleans the internal surface of a pipe by the front-end part and the external surface thereof when passing therethrough or applies a protective coating to the internal surface of a pipeline. Said device is moved inside the pipe by a working body in the form of compressed air (gas) or a liquid under pressure. Said invention uses the elastic flexible, airproof or waterproof properties of a material, in particular foamed polyethylene, and the capacity thereof to modify the shape by external forces and reshape without frozen strain or with small amount thereof, the external forces being eliminated. In order to introduce the device (wad) inside the tube a mechanism provided with a through inside orifice can be used. Said orifice has on one end thereof a cylindrical part having a large diameter which contains one or several wads, a cylindrical part having a lesser diameter on the other side through which the wad penetrates into the pipe, and a tapered junction (contraction) from the larger part to the narrow part.</p> |
