| 摘要 |
807,413. Shaping ends of pipe liners. TUBOVIT S.P.A. June 26, 1956 [June 27, 1955 ; April 12, 1956], No. 19796/56. Class 87(2). [Also in Group XXVIII] In a process for lining non- thermoplastic pipes, the end of a liner of thermoplastic material, such as polyvinyl chloride, polyvinyl acetate copolymers, vinyl chloride or vinylidene chloride copolymers, or polyethylene, is tapered by pressing that end into a tapered die 42 heated by resistors 43. |
