METHOD AND APPARATUS FOR MANUFACTURING THERMOPLASTIC RESIN PIPE

摘要

PROBLEM TO BE SOLVED: To provide a method for manufacturing a thin-walled large caliber thermoplastic resin pipe free from cooling irregularity and having a homogenous surface and beautiful appearance. SOLUTION: A thermoplastic resin is melted to be continuously extruded in a tubular form from a die 3 and the inner peripheral surface of the extruded molten tubular body 4 is brought into contact with an inside cooling cylinder 11 to take off the tubular body 4 while cooling the same to manufacture a thermoplastic resin pipe. The inside cooling cylinder 11 has a plurality of cooling rings 11a-11d and the molten tubular body 4 is brought into contact with the cooling rings 11a-11d at a plurality of positions spaced apart from each other in the take-off direction of the molten tubular body 4 and cooled uniformly. COPYRIGHT: (C)2005,JPO&NCIPI