The relationship between blanking gap and service life of stainless steel terminal mold

In the design of the stainless steel terminal mold, the setting of the gap is particularly important. A reasonable gap is closely related to the life of the mold. 1. Adjustment of the gap between the stainless steel terminal mold The module installation positioning hole in the male and female mold fixing plate is worn out due to frequent and multiple combinations of the mold core, resulting in a large gap after assembly (loose after assembly) or uneven gap ( Positioning deviation), which will cause the shape of the cross section to deteriorate after punching, the punch is easy to break, burrs, etc., so a paper cutting test must be carried out after assembly (the side of the paper sheet is stretched to indicate that the gap is too large), or through After checking the cross-section condition after punching, the reasonable gap adjustment can be obtained by shifting, and the corresponding records can be made. The hole position can also be marked for subsequent maintenance operations. Second, the determination of the reasonable gap of the stainless steel terminal mold The definition of the reasonable gap: For the same gap value, it is very difficult to meet various requirements. Therefore, the reasonable gap actually refers to a range rather than a certain value. (Generally taken value It is: 1/2 of the cut surface of each station between the cracked section and the bright surface) The principle of determining the reasonable gap A. When the quality of the workpiece section is not strictly required, select a larger gap to increase the life of the die and reduce the punching force. B The quality of the workpiece section and When manufacturing tolerance requirements are high, choose a smaller gap. C When determining the size of the upper and lower blades of the mold, consider that the wear of the mold during use will make the blade gap larger, and the GAP min value should be selected for calculation. Third, the blanking gap of the stainless steel terminal mold The relationship with the life of the stainless steel terminal mold In the punching process, the pressure on the die edge is very large, causing local adhesion between the die edge and the material contact surface, resulting in adhesion and wear. The amount of wear is proportional to the contact pressure and relative sliding distance, and inversely proportional to the yield strength of the material, which is the main form of mold wear. When the gap is small, the contact pressure will increase, the friction distance will increase, and the friction heating will be serious, which will increase the wear of the mold, cause the bonding phenomenon between the mold and the material, and cause the compression fatigue damage of the cutting edge, causing it to collapse. The gap is small, the friction between the blanking part and the cutting edge is large, the cutting edge wear is large, and the life is shortened. When the gap is large, the bending and stretching of the material increases relatively, and the positive pressure on the end of the die edge increases, which is easy to produce chipping or plasticity Deformation and aggravate wear. The gap is large, the friction between the blanking part and the cutting edge is small, the cutting edge wear is small, and the life is extended. Too large or too small a gap will reduce the life of the mold. Therefore, if the gap is appropriate or the mold gap is appropriately increased, the friction between the convex and concave molds and the material can be reduced, and the unfavorable factors of uneven gap can be reduced, thereby increasing the life of the mold. The end face of the female mold wears more than the male mold. The reason is that the material on the end face of the female mold slides freely, while the sliding of the material under the male mold in the direction of the plate surface is restricted. The wear on the side of the punch is the greatest, because the side of the punch is subjected to the long-distance friction of the discharge action, which intensifies the wear. In order to improve the life of the stainless steel terminal mold, a larger gap can be used; if a smaller gap is used, the hardness and manufacturing accuracy of the mold must be improved, and the cutting edge of the punching die must be fully lubricated to reduce wear.