Stamping processing is one of the effective processes for the production of large-volume parts forming. Mold damage is a common problem in stamping production, which often causes the entire line to stop production and affects the product delivery cycle. Therefore, it is necessary to find the cause of the mold as soon as possible and repair it properly.
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1. Mold damage
Mold damage refers to mold cracking, breakage, expansion, etc. To solve the problem of mold damage, we must find the reasons from the design, manufacturing process and use of the mold. If conditions such as foreign matter entering the mold, stacking of parts, and waste obstruction are not dealt with in time, and the processing continues, it will be easy to damage the blanking plate, punch, lower template and guide pillar of the mold.
If the spring force design is too small or the contour sets are of different heights, the spring will crack and the blanking plate will be skewed, resulting in overlapping impact and damage to the parts. If the quenching temperature of the mold is too high, the quenching method and time are unreasonable, and the tempering times, temperature, and elbow space are not selected properly, it will cause damage to the mold after entering stamping production. Improper fixation of the punch or insufficient screw strength may cause the punch to fall or break. The working height is adjusted too low and the guide pillar is not smooth enough. Generally, the heat treatment process of mold materials has a great influence on it. If the size or depth of the blanking hole is not designed properly, it is easy to block the slot and cause damage to the blanking plate. When the mold is used, the position and direction of the parts are installed incorrectly or the bolts are not tightened properly.
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2. Card mold
The primary causes of mold jamming are: incorrect mold guidance and skewing. Otherwise, the fault will be expanded and the mold will be damaged. Causes mold deformation, for example, the hardness and thickness of the mold base and template are too small and are easily impacted and deformed by external forces; the mold position is incorrectly installed, and the positioning errors of the upper and lower molds are out of tolerance. At this time, the strength of the punch should be increased and the guidance and protection of the discharge plate should be enhanced.
Or the accuracy of the press is too poor, causing interference with the mold; the strength of the punch is insufficient, and the position of the large and small punches is too close, causing the lateral force of the mold to be unbalanced. During the stamping process, once the mold clamping is inflexible or even stuck, production must be stopped immediately to find out the cause of the mold jam and eliminate the fault.
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3. Mold damage and repair
The cost of molds for stamping production is high. Generally, the mold cost accounts for 1/5-1/4 of the total cost of the parts. The one-time correction cost exceeds 70% of the original cost of the die, or the life of the die is approaching. When the mold repair technology is too complex, the mold repair cost is too high, and the difficulty will inevitably make the repair cycle too long, which will seriously affect the normal production of stamping, you should choose to fail early and make the mold again. Generally speaking.
After the mold is damaged, there is also a choice between repair and scrapping. But. Therefore, repairing the mold in time to avoid mold damage can greatly reduce the mold cost of stamping production. When the bonding parts of the mold are seriously damaged, sometimes the convex and concave molds are damaged at the same time. This is because, in addition to the difficulty and high cost of making molds. Non-natural wear failure of stamping dies, such as damage to non-bonded parts.
Under normal circumstances, the main failure mode of stamping molds is excessive wear. The mold is re-made and delivered for use. Until the burr of stamped parts exceeds the budget, and the size and shape of the parts are precise.
