Reducing tube dia. and wall thickness - by drawing through die using self-centring core formed as truncated cones connected at small ends

摘要

The arrangement is intended for drawing a tube to reduce its dia. and wall thickness using a drawing die and a self-centering drawing core. The core is so arranged that, after being reduced in the die, the tube dia. is increased by passing over a further portion of the same core. The first portion of the core is pref. frusto conical with its larger dia. pointing against the direction of tube movement and slightly smaller than the inner tube dia., whilst its second portion is also truncated conical with its smaller dia. equal to and fixed to that of the cone and out of contact with the tube wall.