| 摘要 |
PROBLEM TO BE SOLVED: To provide a cross head die for molding a vinyl chloride resin pipe which suppresses the retention of a resin in the molten resin passage in the cross head die, reduces the occurrence of a defective appearance and abnormal molding by making the flow of the resin uniform, and can make production for a long time possible. SOLUTION: The contact surfaces 11 of at least two components forming an annular clearance 5 through which a molten resin mainly containing the rigid vinyl chloride resin passes are formed to be perpendicular to the molding line direction, and a contact surface connected to the annular clearance in parallel with the molding line direction is not provided. The length of the parallel part 41 of a mandrel 4 forming the annular clearance 5 has an axially asymmetric structure in which the inflow side 41a is longer than the confluence side 41b. COPYRIGHT: (C)2006,JPO&NCIPI |
