METHOD AND APPARATUS FOR MAKING AN EXTRUSION PRODUCT, AND ANEXTRUSION PRODUCT

摘要

The invention relates to an extruder with which material is extruded through a tool (2). Fluoropolymer is used between the extrusion material and the tool (2) for reducing friction between the material and the tool. At least the surface of the tool (2) against fluoropolymer is of a material whose thermal conductivity is greater than the thermal conductivity of ordinary tool steel. Therefore the friction heat generated can be conducted efficiently away from the interface between the tool (2) and the extrusion material towards the tool (2), whereby the wear of fluoropolymer can be reduced and thus the durability of the tool (2) can be improved. In that case the extrusion product will slip evenly out from the tool (2), whereby the surface of the product is essentially smooth without transverse microscopic stripes repeated at a specific wave length.