원형빌렛으로부터 인볼루트 헬리컬 핀을 가진 제품의 비틀림 압출가공공정에 관한 연구

Abstract

The twisting and extrusion process of the product with involute helical fin from the round billet is developed by the upper bound analysis. The twisting of extruded product is caused by the twisted die surface connecting the die entrance section and the die exit section linearly. In the analysis, the internal shear surface is defined as the curved twisted plane from the taisting of die surface and the shear work is calculated by the consumption of shear energy The increase rate of angular velocity is determined by the minimization of plastic work. The results of the analysis. It is shown that the angular velocity of the extruded product increases with the die twisting angle, the reduction of area, and decreases with the die length, the friction condition.