Metal working apparatus and methods of piercing

摘要

A method and apparatus are provided for piercing metal members at high temperatures, particularly members containing slag inclusions, by the steps of urging said member, over a piercer point by rolling whereby said point passes through and forms an axial opening in the ingot, said point being formed of an alloy comprising 0.015% to 2% Carbon, about 5% to 65% Cobalt, about 15% to 35% Chromium and up to about 30% iron.