| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for expanding or contracting a pipe which expands or contracts one of pipes to be joined together without changing the length of the pipes and can directly joining the pipes together without piecing or cutting the pipes. SOLUTION: In the method for expanding or contracting the end part of the thermoplastic resin pipe, a part to be expanded or contracted of the pipe is immersed in high temperature oil, so that the the thermoplastic resin is heated to the extent that the thermoplastic resin can be deformed. The part is taken out and externally engaged with a cylinder having a diameter to which the diameter of the part is expanded through a guide part or internally engaged with a cylindrical space having a diameter to which the diameter of the part is contracted. COPYRIGHT: (C)2005,JPO&NCIPI |
