PREPARATION OF CORROSIONNPROOF METAL PIPE

摘要

PURPOSE:To obtain a metal pipe being excellent in oil-proof and chemical resistance properties by closely fitting a silyl modified polyolefin tube on to the inner surface of the pipe and cross-linking the same. CONSTITUTION:A silyl modified polyolefin tube 6 which is not yet cross-linked is extruded into a heated metal pipe 5 in such a manner that the tube does not touch the inner wall of the pipe and at least a part of the tube 6 is stuck to the inner wall of the metal pipe. Next, after the tube 6 is cut near the inlet of the pipe 5, the pipe 5 is rotated at a high speed around the center thereof as a rotary axis and thereby the tube 6 is closely fitted on to the inner surface of the pipe 5. Then the tube 6 is made to react to the moisture in the presence of a silanol condensation catalyst and to perform cross-linking, thus a corrosion-proof metal pipe is obtained.