METHOD AND APPARATUS FOR PRODUCING PLASTIC-COVERED STEEL PIPE

摘要

PURPOSE:To obtain a steel pipe covered with a plastic having a uniform thickness, by arranging downstream of a round die for extruding a plastic cover and along a conveying path for a steel pipe a plurality of flexible support members each having an opening through which the steel pipe will be passed. CONSTITUTION:A plurality of support members 4 are arranged downstream of the round die 8 for extruding a plastic cover and along the conveying path for plastic-covered steel pipe 2. The support member 4 comprises a rigid holding plate 5 having an opening and a rubber sheet 6 fitted and secured to said opening. The rubber sheet 6 has an approximately round central opening 7 through which the plastic-covered steel pipe 2 will be passed in a supported manner. Therefore, the plastic-covered steel pipe 2 that is inserted into the rubber sheet 6 is supported at surface by the flexible central opening 7 of the rubber sheet 6.