Elbow forming composite die - has inlet guide, swaging, and tubular bending sections, and is for shaping of straight pipe lengths

摘要

The composite die for forming an elbow from a straight tube pushed through. It comprises a tubular inlet guide section, and a swaging section in the form of a truncated cone connected and opening at its large end to one end of the inlet guide section. The swaging section is constructed and arranged so that the tube while pushed through it is subjected to circumferential swaging forces varying from a maximum at one location on its circumference to a minimum value at another opposed location on its circumference. The tube is subject to an offset of die forces producing a force movement, to cause bending of the tube about the location subjected to the minimum swaging forces and thickening of the tube wall, partial forming of the elbow and reduction in tube diameter.