VERFAHREN UND STRANGPRESSWERKZEUG ZUR HERSTELLUNG EINES ROHLINGS MIT INNENLIEGENDEN BOHRUNGEN.

摘要

The invention relates to an extrusion process and an extrusion tool for the production of cylindrical metallic or ceramic blanks having one or more internal twisted longitudinal bores. A plasticized, pulverulent starting material, deformable by means of extrusion, is forced through a space formed by a die and a mandrel. One or more twisted central pins of a rigid material are fastened to the mandrel which ends before the inner space of the die. The central pins form the longitudinal bores in the blank. The positioning of the longitudinal bores is extremely symmetrical within the blank and uniformly achieved in the various individual blanks extruded using the same production batch.