PURPOSE: To obtain the molded product without foaming, preventing the deterioration of the properties of the molded product by cooling under pressure the molded product immediately after it has been extruded.
CONSTITUTION: The cross head of an extruding machine connected to the cylindrical cooling tank 3, is caused to be a closed system, and said closed system is pressurized by feeding air or nitrogen gas. The molded product made of silane cross linked polyolefine extruded from the extruding machine, is cooled by such pressurized atmosphere. Consequently, the molded product without foaming in a coated portion is molded. Thus, the foaming of silane cross linked polyolefine resin at extruding process may be suppressed, omitting the control for the set temperature of the extruding machine, the revolution number of a screw and the blended amount, etc.
OOTANI KENICHI
HIRUKAWA HIROSHI
NISHIYAMA HIDEMI