Determination of blank shapes for drawing irregular cups using an electrical analogue method

An electrical analogue method is introduced to determine optimum blank shapes for deep-drawing cups of irregular cross-section. Square and rectangular cups were drawn from aluminium and steel blanks having these shapes and required very little trimming. Comparison is made with other methods of developing blanks and although one empirical method gave reasonable results for rectangular cups it is concluded that the electrical analogue method is preferred; it is also applicable to irregularly shaped cups.