SHAFT FORGING METHOD Russian patent published in 1995 - IPC

FIELD: forging equipment. SUBSTANCE: method of forging shafts includes steps of heating an ingot, upsetting it an broaching, upon deformation process providing a displacement of an inner central zone of the ingot onto its surface. In order to perform that, the upset ingot is being broached and expanded along its diameter, and cone cylindrical broaching tools are being alternatively embedded into an opening, had been made. Each subsequent tool has a diameter of its cylindrical portion more, than a previous one. A ring, had been made, is being chopped to separate parts, then being straightened for forging a shaft from each part. The axial defect zone, had been displaced onto the surface, is being partially removed with the scale at subsequent heating operations, and it is being completely removed upon working of the shaft forging. In the result a quality of the metal, had been remained, is significantly enhanced, as the axial zone contains a large number of additives. The expansion of the broached blank along its diameter enhances structure of metal in the whole body of the forging, providing extremely high mechanical properties of shafts metal. After chopping the ring forging to separate parts, blanks for forging shafts are being made. EFFECT: enhanced quality of shafts. 1 cl, 9 dwg