Stamping and Die Technology: What to do with high-speed precision stamping continuous dies?

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　I. Calculation of the force required for punching and blanking: ①: Understanding the force needed for stamping and cutting processes is also essential for selecting the appropriate stamping machine or designing the molds. 　　②: In blanking processing, problems such as breakage of the punch edge and damage to the shoulder may occur. Most of these problems are caused by insufficient technical data for the parts, as well as incorrect selection of the material and shape of the punch and die. 　　③: Formula for calculating punching force: II. Shear strength and tensile strength of various materials: III. Calculation of the minimum punching diameter: The diameter of the smallest circular hole in the die, or the thickness of the weakest part of the punch, should be calculated in advance so that appropriate measures can be taken in advance. 　　IV. Calculation of the effective length of the punch blade: ①: Formula for calculating the longitudinal bending load of the punch. ②: As can be seen from this Euler formula, to increase the longitudinal bending strength P, it is sufficient to use discharge guides, select materials with higher longitudinal elastic coefficients (SKD→SKH→HAP), and reduce the length of the blade. 　　③The longitudinal bending load P represents the value at which the punch is damaged due to longitudinal bending stress; when selecting a punch, a safety factor of 3 to 5 must be taken into account. 　　④When punching small holes, special attention must be paid to the longitudinal bending load and the stress applied to the punch when selecting it. 　　⑤: [Technical parameters] Calculation of area, center of gravity, and second moment of area: V. Methods to reduce punching force: ①: As a method to reduce shear force, the approach of using an additional shear angle as shown in [Figure 2] can be employed. During blanking and cutting operations, a shear angle is defined on the die ； During punching, a shear angle is taken on the punch. 　　②: For size H, a shear angle equal to or greater than the plate thickness is often used. By the way, setting the H dimension of the shear angle to around the plate thickness can reduce the machining force by about 30%.