Preparation of plastic coated steel pipe

Abstract

Abstract PURPOSE: To form a shark skin like embossed pattern on an outer surface of a coated plastic by mainting a temp. in the vicinity of an extruding port lower than a plastic temp. in preparing the plastic coated steel pipe. CONSTITUTION: After the plastic 8 is filled in a plastic storage chamber 9 within a die 6, a heater 13 is operated to heat to an extruding temp. Subsequently, in order to control a height and a pitch of the embossed portion formed on the outer surface of the plastic coated steel pipe to a desired value, a cooling air blowing apparatus 14 is operated to initiate the cooling of a lip portion 12 so as to adjust the temp. differential between the lip portion 12 and the plastic in the storage chamber 9 to an objective value. Then, if the coating of the plastic to an original steel pipe 5 is initiated according to a conventional method of an extrusion method, the shark skin like embossed pattern having a predetermined height and a pitch is formed on a surface of the coating layer. As described above, the inexpensive anti-slip embossed pattern is formed on the surface of the plastic coating. COPYRIGHT: (C)1981,JPO&Japio

Inventors

• 👤 Shigemichi Yamauchi
• 👤 Sadaki Okada
• 👤 Yoshikazu Izeki

Bibliographic Details