Pilger tube mill - with two feed carriages gearboxes and mandrel thrust blocks for higher throughput

摘要

A Pilger or rotary forge mill for tubes has two gear boxes, driven by the main motor and driving separate feed carriages for the billet. Both feed carriages have a catch which acts against the rear of a billet to be fed forward. Both gear boxes are fitted with a rapid approach gear stage. The distance between the two mandrel thrust blocks in the gear boxes is made twice the length of a billet. This reduces the time of the break in the feed to a few seconds. During the transfer from one feed carriage to the other, at least one of the mandrel thrust blocks is closed so that the rolling mill stand need not be stopped. The throughput is therefore considerably raised (time loss of 4-8 instead of 26-60 seconds per billet).