| 摘要 |
PROBLEM TO BE SOLVED: To prevent a flat rigidity of a rubber ring faucet from decreasing by not collapsing a rib, to surely connect a spigot of a tube to the faucet by reducing unevenness of an inner diameter of the faucet, and to surely hold watertightness of the faucet by the rubber ring by mounting the ring at the faucet having a smooth inner surface. SOLUTION: A method for working a radially enlarged faucet of a tube with inner and outer smooth waves comprises the step of removing an outer layer 26 formed on an end 12d of the tube 50 with the inner and outer smooth waves. The method further comprises the steps of heating the end 12d of the tube in which the layer 26 is removed to a temperature of softening point lower than a melting point. The method also comprises the step of forming the rubber ring faucet 14 by radially enlarging the end 12d of the tube. Thus, since the end 12d of the tube is radially enlarged in a state in which the layer 26 is removed, a rib 18 is not collapsed by the layer 26. Since the rib 18 is not collapsed, an inner peripheral surface 14a of the faucet 14 can be formed smooth. Accordingly, the unevenness of the inner diameter of the faucet 14 is reduced. COPYRIGHT: (C)2003,JPO |
