Investigation of the effect of blank holder force distribution on deep drawing using developed blank holder divided into double rings

A new blank holder divided into double rings is proposed, in which the blank holder force (BHF) can be independently and effectively applied on different flange regions. In this paper, the principle and characteristics of the new blank holder technique are expatiated by theoretical derivation and stress analysis. All results indicate that the distribution of BHF applied by the double rings blank holder is more reasonable than a single blank holder under the condition of proper parameter selection, and the wrinkling can be better suppressed. The effectiveness of the double rings blank holder has been proven by deep drawing experiments. Using the new blank holder technique, the flange wrinkling was demonstrated to be more eliminated than that using the single blank holder. Moreover, experimental results also corroborate that the parameters of BHF distribution ratio and the boundary diameter of the two rings have a great influence on the effects of the new blank holder technique.