Calculation formulas of punch and die plate dimensions in stamping die designing

In the standard designing procedure of stamping die, the calculation formulas of dimensions of both punch and die plate are derived based on such a principle that for blanking operation to produce the punch with the die plate as the basic part, and for the punching operation to produce the die plate with the punch as the basic part. But in practice, due to the condition and tradition, for both the blanking and punching, the usual way is to produce punch first and then the die plate, or in the opposite way, so the conversion between them is needed. In this paper, based on the theoretic formula for standard part and considering three situations which occured after wearing: enlarging, shrinking and unchanging, a practice oriented calculation formulas for dimensions ( A n, B n, C n) are derived by converting the standerd part to the non standard, illustrating analysis, and transforming the formulas. By the derived formulas, the problem is solved that the dimensions calculating has′nt corresponding formnlas when the first producing part is non standard.