MANDREL HOLDING AND RELEASING MEANS

摘要

An arrangement for securing and easily releasing a mandrel from a mandrel rod upon their advancement and return movements during the piercing operation of a seamless tube. Between the mandrel and rod is an intermediate piece having one or more openings for receiving a hook with a nose extending into an opening of the mandrel. The hook is biased into position by a spring mounted around its one end and at its other end beneath a nose is a tapered surface for contacting a corresponding surface of the mandrel to pivot the hook away from the interior of the mandrel to release the mandrel from the intermediate piece and mandrel rod.