METHOD FOR INNER HIGH PRESSURE FORMING HOLLOW, REMOVED SHAFTS MADE OF COLD FORMABLE METAL

摘要

PCT No. PCT/DE94/01300 Sec. 371 Date Jul. 12, 1996 Sec. 102(e) Date Jul. 12, 1996 PCT Filed Nov. 3, 1994 PCT Pub. No. WO95/12466 PCT Pub. Date May 11, 1995The invention relates to a process for forming hollow stepped shafts of cold-formable metal by internal high pressure with the following steps: provision of a tube outlet section and filling it with fluid; sealing at least the tube section to be widened; application of a suitable high internal pressure for widening the tube section; calibration of the workpiece by applying a high calibration pressure; maintenance of the calibration pressure while heading the tube along the longitudinal axis. Internal tools, also spring-loaded tools, are provided as supports in the tool.