| 摘要 |
<p>PURPOSE:To surely prevent the element pipes of a double pipe from becoming disjoined from either of both ends by a method wherein wire is wound onto the exposed part of the outer surface of an inner pipe inserted in an outer coating pipe at the positions as near as possible to the outer coating pipe and fixed to the inner pipe with bonding agent. CONSTITUTION:A polyvinyl chloride inner pipe 2 is inserted in an outer coating pipe 1 in such a manner that both the ends 2' and 2' of the inner pipe 2 are exposed in uniform length, which fit the length of the socket part 3' of a joint pipe 3. After that, steel wires 4 are wound onto the exposed parts of the outer surface of the inner pipe 2 at the positions as near as possible to the outer pipe 1 and coated with bonding agent 5. One full turn of winding of the steel wire is normally required. However, a plurality of turns are necessary or no less than one turn of winding is enough, depending upon the wire diameter, the weight of the outer coating pipe, the magnitude of the gap between the outer and inner pipes. As for the bonding agent, the agent, which has affinity for both polyvinyl chloride pipe and steel wire, is selected and epoxy resin, unsaturated polyester resin or the like is available.</p> |
