| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for producing a hollow pipe with improved cooling efficiency.SOLUTION: The method for producing a hollow pipe of the present invention comprises a shaping step and a cooling step. In the shaping step, a thermoplastic resin is shaped to obtain a hollow tubular resin. In the cooling step, a cooling fluid is circulated between hollow interior and outside of the hollow tubular resin to cool the hollow tubular resin from the inner wall. This constitution enables the cooling fluid to be continually replaced by generating a circulation flow actively in a wide range of the hollow interior of the tubular resin, thereby resulting in efficient cooling of the tubular resin.SELECTED DRAWING: Figure 1 |
