摘要 |
A method is provided for continuously manufacturing a synthetic resin tube. A plurality of pre-molded flat strips of synthetic resin material is passed through a heating zone to soften the strips. Then, the strips thus softened composed of a first strip for forming an outermost tube wall, a second strip for forming an innermost tube wall and at least one intermediate strip for forming an intermediate tube wall sandwiched between the first and second strips are fed to a mandrel comprising a plurality of rotating rollers arranged in a circular array and rotatably journalled in an end plate. The strips fed to the mandrel are wrapped around and advanced axially along the length of the mandrel with portions of adjacent turns of the intermediate strip not overlapping each other. The strips thus wrapped around the mandrel is then pressed by a pressure roller so as to be joined and welded to form a tube.
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