| 摘要 |
PURPOSE:To improve productivity of a lining bent pipe, by a method wherein a synthetic resin pipe heated and softened by an arm, which is of a board shape in cross section by making a direction of a rotary shaft center into a long side, and is of a circular arc shape, and the said rotary shaft is situated at about the central point of the circular arc of a metallic bent pipe, is molded into a bent pipe. CONSTITUTION:After a straight pipe 1' with a 90 deg. short elbow has been put on a first and second clamps 3, 16, the straight pipe 1' is fitted with a first arm 7 inwardly from a bent side of the straight pipe 1' and a bottom force 4 is closed. Then a vinyl pipe 2' in a state of a straight pipe is pressed into a pressing-in piston 36. Then the vinyl pipe 2' is pressed into the straight pipe 1' by moving a receiprocating sheet 37 where the pressing-in piston is mounted and fixed. In this instance, the vinyl pipe 2' is pressed into the first arm 7 and a bent part can be molded. Then only the pressing-in piston is moved backward. Then pressurizing air is introduced into the vinyl pipe 2', blow molding is performed and stuck close to the inside of the straight pipe l'. A lining bent pipe can he manufactured at favorable productivity in this manner. |
