GB1462199A - Metal working apparatus - Google Patents

Abstract

1462199 Billet piercing; extruding COMBUSTION ENG Inc 19 July 1974 [23 July 1973] 32147/74 Headings B3H and B3P A billet piercing press which can also be used to extrude the pierced billet comprises a longitudinal tubular member 16 which is divided internally by a pair of spaced end members 22, 24 to define a cylinder 18 therebetween for a drive piston 32 and a working region 20 in which a billet container 86 is retained. The piston 32 is hydraulically operated and cushioned at each end of its stroke. A piston rod 38 is fixed to the piston 32 and extends through the end member 22. A piercing mandrel 70 is fixed to the end of the piston rod 38 by collet jaws 78 or by screwing or welding. The mandrel has a replaceable tip 80. A heated billet 14 is located in the billet container 86 by removal of the upper end closure 90. The billet may be dropped or forced into the container 86 by a plunger 138, Fig. 6, on a plate 136 connected to the end of the piston rod 38 by parallel rods 128. The end closure 90 has a central bore 110 through which the piercing debris is removed. The billet is centred in the container by tapers 106 on an upper centring plate. The billet may have a centring recess 116, Fig. 6. After piercing the mandrel 70 is retracted and its tip 80 may be replaced by a push plug (81), Fig. 5 (not shown), to eject the pierced billet. The plug may alternatively seat on the tip 80. If the pierced billet is to be extruded the tip 80 is replaced by an extrusion tip. The end closure plate 90 may be constructed of an inner part 148, Fig. 8, and an outer part 146. After piercing the inner part 148 is removed so that the bore 150 of the outer part defines an extrusion opening.