METHOD FOR MANUFACTURING PLASTIC EXTRUSION MEMBER

PURPOSE:To obtain a plastic extrusion member without any cooling stripes on its surface and with an excellent appearance by cooling slowly the surface temperature of an extrusion member extruded from a plastic extruder in spraying gas such as air or the like at first to specific temperature, after that, by cooling it gradually in use of warm water and cold water below the specific temperature. CONSTITUTION:A covered electric wire extruded from a die 1 is cooled at first by spraying gas, for instance, air from an air nozzle 3 right behind a die 1. Subsequently, it is cooled by pouring warm water 5' below 100 deg.C from a cooling water spouting device 4a and then cooled by pouring cold water 5 from a cooling water spouting device 4b. This is aimed to prevent the boundary surface of temperature difference such as liquid from generating on a covering member by slowly cooling it at first through gas such as air or the like. By this cooling, the cooling member is cooled at temperature of 100-130 deg.C and subject to be cooled consequently, under the condition lower than the temperature displacement point of the covering member, for instance, by next warm water of 90 deg.C and cold water of 15 deg.C, so that the contraction difference of the covering member becomes considerably low and the generating of cooling stripes does not occur thereupon.