| 摘要 |
In the manufacture of poppet valves, in which the head of the poppet valve is to be welded to the shaft, a finished-shape die (1) is, for simple automation of the head manufacture, to be filled in the shaft region and widened shaft region by cold extrusion of a heated cylindrical blank (4) cut to length and the poppet region is to be filled by immediately following upset-pressing. These processes can also be carried out, without changing the working station, in a device in which, in a support frame, a finished-shape die of sintered metal for the head of the poppet valves with a cylindrical guide region on the poppet side and a force-actuated annular piston (6) are provided, which piston fits into the guide region and into the internal region of which a blank is inserted onto a coaxially arranged, force-actuated cold extrusion ram (7) which is axially displaceable both together with the annular piston and relatively to the latter. …<IMAGE>… |
