| 摘要 |
PURPOSE:To carry out continuous supply by joining a thermoplastic sheet during a coating process, in a device coating spirally the outside diameter of a steel pipe with the thermoplastic sheet while turning the steel pipe. CONSTITUTION:A thermoplastic polyethylene sheet 20 is supplied, a looper device 5 is provided on the first portion of a coating part 4 coating the outer diameter of a steel pipe 1 by a coating roller 2 and supply roller 3 and the sheet is reserved. A tail end of the sheet of a coil 7 is joined to the tip of the next coil 9 by a sheet joining device 10. At this time, the sheet of the looper device 5 is sent out and coating continues on without interrupting the coating process of the steel pipe. |
