| 摘要 |
PURPOSE:To make it possible to obtain a bent pipe easily, by making a molded pipe of a synthetic resin material low in resiliency at normal temperatures have such a constitution that the larger diameter section of the bent art is thicker than the small diameter section, and the small diameter section has indentations. CONSTITUTION:A straight pipe 11 is designed to be equivalent in length to the length (L) of the intended bent pipe 10. Then the straight pipe 11 is formed with indentations 12a, 13a at parts 12, 13 that so that the straight pipe 11 may be formed with curves corresponding to curves R1, R2 of bent parts 10a, 10b of the bent pipe 10, and the thickness of the parts 12, 13 is reduced more than the other part to prepare a pipe 14. The pipe 14 is molded, and before the resin is solidified completely, the pipe 14 is removed from the mold, and the parts 12, 13 corresponding to the bent parts 10a, 10b are bent. When an external force is applied to the parts 12, 13, they buckle and are collapsed to be bent. When a desired (R) is attained, the application of the bending force is stopped, and the pipe with the pressure being applied is cooled to be solidified. |
