| 摘要 |
A method and apparatus are disclosed for covering a metal pipe, particularly of the type utilized in modern heating systems, with a continuous covering of a pre-cut web of foamed plastics material which is folded around the pipe and sealed along its contacting edges. Over said foam, an impervious and nonpermeable film is then extruded serving the dual function of an insulating finish and casing for the insulated pipe. The coating apparatus comprises a station (10, 11, 12) for pre-heating a foamed plastics material web (5), wrapping the web around a metal pipe (1) and sealing or welding the web edges, a pipe cooling station equipped with sleeves (16, 17, 18) wherethrough cooling compressed air is circulated and a web covering station (31) for covering the web (5) by continuously extruding a thermoplastics material thereon in such a way as to form a strong protective film on the web coating the pipe (1). Thus a doubly coated metal pipe is obtained having enhanced thermal characteristics, and lends itself excellently for the implementation of space heating systems in conformity with current regulations on the reduction of energy consumption. |
