| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for bending a thermoplastic resin pipe by which the after-treatment of the pipe is easy and its handling is simple and further, an excellent workability and a high production efficiency beyond a conventional level are realized. SOLUTION: When the thermoplastic resin pipe 10 is thermally bent, a rubber core 20 of a hollow cylindrical shape whose one end part is blocked is inserted into the thermoplastic resin pipe 10 and inflated, and the pipe 10 is bent in such a state that a specified pressure is applied to the inner face of the pipe 10 by the rubber core 20. In addition, the rubber core 20 is preferably of such a type that it has a regulator connected to a source of a gas to be injected, at the other end part, and the amount of the gas to be injected is controlled by the regulator to maintain an inner pressure at a constant level. |
