| 摘要 |
PURPOSE:To prevent softening of a fiber due to heat at the time of extrusion molding, by making a heat insulating and heat resisting material interpose between the fiber passing through a nipple and the inside of the nipple. CONSTITUTION:A heat insulating and heat resisting tube 8 to be obtained by making a plaited tube made of a crosslinking fiber made of phenol formaldehyde impregnated with heat resisting paints, for example, silicon series heat resisting paints is fitted in the inside of a nipple 6 and a nipple holder. The size of the heat insulating and heat resisting tube 8 to be used hereupon is selected appropriately according to thickness of the fiber 5. After the heat insulating and heat resisting tube 8 has been fitted in the nipple 6 and adjustment of non-uniform thickness has been performed by inserting the fiber 5 through the nipple 6 and a die 4, high concentration polyethylene external coating 10 is molded through extrusion. As softening of the fiber at the time of piercing of the fiber through the nipple is prevented by insulating the inside of the nipple thermally, outlet work of the extrusion molding becomes easy and generation of extension and a flaw on the fiber at the time of the extrusion molding does not occur. |
