| 摘要 |
The invention relates to a multilayer tube assembly and a method for producing the same. In particular, the present invention relates to a multilayer tube assembly, which may be used in sanitary and heating installations. The multilayer tube assembly according to the present invention comprises a seamless copper 1 tube provided on its external surface with an oxide layer 2 having a thickness of 0.1μm to 1μm; at least one intermediate 3 adhesive layer on said oxide layer 2 consisting basically of LLD-PB and containing 1 wt.-% to 2 wt.-% of an additive metal deactivator; and at least one outer polymeric layer 4 provided on said intermediate adhesive layer 3 and consisting mainly of a high-molecular polymeric material and 2 wt.-% to 4 wt.-% of an additive flame retardant. The multilayer tube assembly is produced by a method comprising the steps of: cleaning said seamless copper 1 tube with a petroleum-based agent; oxidising the external surface of said seamless copper tube 1 a) for multilayer tube assembly having an outer diameter less than 32 mm, in an atmosphere of nitrogen and air at a temperature range of 550° C. to 700° C., or b) for multilayer tube assembly having an outer diameter larger than 32 mm, in atmospheric air at a temperature of 150° C. to 250° C. and in a flame station comprising multiple flame nozzles around the perimeter of said tube; extruding said intermediate adhesive layer 3 onto said seamless copper 1 tube at a temperature range of 200° C. to 230° C.; and extruding said outer polymeric layer 4 onto said intermediate adhesive layer 3 at a temperature range of 210° C. to 250° C. |
