GB370274A - Improvements in extrusion presses - Google Patents

Abstract

370,274. Squirting. FIELDING & PLATT, Ltd. and ROWLES, R. V., Atlas Works, Gloucester. July 6,1931, No. 19438. [Class 83 (iv).] Billet-piercing.-An extrusion press is adapted for operation either by the direct or indirect method, the die being carried on a crosshead which is positively movable in the longitudinal direction by the main cylinder or cylinders and also movable by secondary means dependent upon the movement of the billet container. In operations by the indirect method, Fig. 1, the container d is moved to the left by the rams n to encircle the billet c ; the container, on further movement to the left, engages stops on the ends of tie-rods r and carries with it the slidable crosshead k and attached die holder b, thus forcing the billet over a stationary piercing bar e ; this bar is centred by a guide ring f which is pushed backwards by the movement of the container. Extrusion is effected by movement of the die a and crosshead k to the left, the pulling force coming from the main press cylinder through heavy tie-rods, the ram o being a stationary fixture on the crosshead o<1>. The guide f, which also serves as a closure for the container during extrusion of tubular bodies, Fig. 4, carries a circular cutter which is used to sever the waste end left at the completion of an operation ; the guide, container and die are moved to the right by means of auxiliary pistons m sufficient to enable a distance-piece h to be slid from between the end of the guide and the holder g for the piercing bar, upon return of the guide &c. to original position the piercing bar is forced to the right and a collar on it moves the circular cutter to sever the waste end. The press may be converted for operation by the direct method by substituting a solid plunger p, Fig. 2, for the piercing bar and utilizing a die a<1> which abuts against the end of the container, the container and die then move forward together during the extrusion operation.