Estimation of the synthetic dynamic accuracy of the die and the press by considering the eccentric load in blanking

Abstract

Manufacturing accuracy is ultimately decided by the synthetic dynamic accuracy of the die and the press in press working. In particular, blanking accuracy is determined by the relative mismatch of the upper die to the lower die in blanking. In this research, deformation of a die set and a press subjected to an eccentric load is analysed. Here, the moment of rotations M and the lateral force Q acting on the boundary between the upper die and the press slide are thought to be expressed by the inclination, Q, and the lateral displacement, D_x, of the upper die. In the blanking experiment, a die set is installed on a 600kN high-precision straight-sided press, and Q and D_x are measured under a dynamic eccentric loading of 50–600stroke/min. Then, estimation of the synthetic dynamic accuracy of the press and the die is examined. The effect of the stiffness of the press is discussed.

The analytical method proposed in this paper can be used in the selection of a press suitable for a given die set and an eccentric load. In precise press working, the selection of the optimum combination of die and press to make the lateral displacement of the punch as small as possible is facilitated by considering the above-mentioned conditions.

Keywords

synthetic dynamic accuracy press die blanking accuracy eccentric load

References

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