A useful facility to the adaptation of precision gear forging by industry, is a quick method of load and flow predictions. In this work, the process of precision forging spur and helical gears is modeled by means of an upper bound analysis. A new velocity field, which includes bulging of the tooth form, is proposed and a computerized incremental procedure for the prediction of the bulged surface profile of the teeth, the forging load, and its increase due to corner filling is presented. The effect of workpiece/die interface friction, gear module, numbers of teeth, helix angle, gear height and bore size on forging pressure are determined. Experimental results obtained for room and elevated temperature forgings compared well with theoretical predictions.

Issue Section:
Technical Papers
Keywords:
forging, production control, production engineering computing
Topics:
Forging, Gears, Pressure, Deformation, Friction
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