RESIN COATING MOLDING DIE

PURPOSE:To reduce a replacing frequency of a molding die and to largely decrease a line pause due to a size replacing operation by gradually reducing a diameter of a divided die through a resin channel toward a discharge side, and sequentially decreasing an inner diameter of a passage through hole of a metal material to the discharge side. CONSTITUTION:A resin channel 4 is provided in a molding die 1, a nipple A5 and a lip A6 are assembled as a pair, and assembled by a cylinder 7 and a bolt A8. Similarly, a nipple B9 and a lip B10 are assembled as a pair, a nipple C12 and a lip C13 are assembled as a pair by a bolt B11, and assembled by a bolt C14. When a steel tube to be extrusion coated has a large diameter, the nipple C12, the lip C13, the bolt C14, the nipple B9, the lip B10 and the bolt B11 are removed, extruded and covered. In the case of an intermediate diameter, the nipple C12, the lip C13 and the bolt C14 are similarly removed, extruded and covered. Further, in the case of a small diameter, all the nipple, the lip and the bolt are removed, extruded and covered.