GB585077A - Method and means for piercing metal bars and billets - Google Patents

Abstract

585,077. Billet-piercing. STEWARTS & LLOYDS, Ltd., and PROTHERO, E. G. Jan. 24, 1945, No. 1870. [Class 83 (iv)] Dies.-In a billet-piercing press the die has a sleeve or liner of less length than either the die or the billet and the sleeve is so arranged as to be withdrawn as the advancing punch pierces and expands the portion of the billet projecting above the sleeve. The opening of the die 12 is of circular cross-section and receives an annular sleeve 10 carried by a lower crosshead 11. The billet 14, also of circular crosssection, fits within the sleeve with its upper portion projecting and its lower end resting on an insert 25 carried by an ejector 13. On the descent of the mandrel or punch 18, the upper projecting end of the billet is pierced and expanded to fill the die space and when the cross-head 15 engages the upper ends of thrust tubes 20 the cross-head 11 is pushed down against the action of resilient or frictional retaining means and so withdraws the sleeve 10 as the punch advances through the billet. The die may be provided with inclined openings 23 for the removal of scale. The ejector insert 25 and supporting column 24 are of approximately square section so as to leave passages within the sleeve 10 also for the discharge of scale. Before the withdrawal of the punch, a stripper plate may be inserted beneath the shoulders 28 on a fixed part of the press.