| 摘要 |
<p>PROBLEM TO BE SOLVED: To improve the adhesiveness between the resin and a metal pipe in a high- pressure resistant compound pipe, in which a metal pipe is built so as to be positioned in the thickness of a synthetic resin pipe body, by drilling multiple through holes in the metal pipe, and filling these through holes with the resin inside and outside of the metal pipe. SOLUTION: A high-pressure resistant compound pipe 20 to be embedded underground such as pipes for water line and sewage is formed by inserting a metal pipe 24 into the thickness of a synthetic resin pipe 22, which is made of polyethylene or polypropylene, and at this stage, the surface of the metal pipe 24 is coated with the primer so as to improve the adhesiveness to the synthetic resin pipe 22. The metal pipe 24 is provided with multiple through holes 26 so that the resin inside and outside of the metal pipe 24 pass there through for bridge. With this structure, the resin inside and outside of the metal pipe 24 are physically connected to each other, and even in the case where an external impact is applied to the high-pressure resistant compound pipe 20 or the high-pressure resistant compound pipe 20 is bent, it is hard to generate a peeling of the resin from the metal pipe 24, and the high-pressure resistant compound pipe 20 having the excellent durability is obtained.</p> |
