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How to prevent the phenomenon of iron filings from trimming the die of automobile stamping parts?

In the trimming of automobile stamping parts, there is generally a phenomenon of iron filings, especially around the lower die scrap knife. The iron filings not only seriously affect the product quality and the cleanliness of the mold appearance, but also reduce the production efficiency. What can be done to prevent this phenomenon from happening?

1. Rationalization of edge clearance

The method adopted for the non-conformity of the plate and the unreasonable cutting edge clearance is to use the OP10 drawing plate buckle to study and trim the profile of each part of the edge mold, and at the same time, the upper and lower cutting edge clearances are adjusted and the eating depth is adjusted.

2. Scrap knife layout and structure optimization

(1) Under the premise of the allowable size of waste conveying equipment and mold structure discharge, the arrangement of scrap knives can be minimized. For example, in the Shanghai Volkswagen scrap knives specification, it is clearly stated that scrap knives should be avoided as much as possible. (2) Optimization of scrap knife structure. Comparing the two, in fact, there are only two differences between the scrap knives in South Korea: one is that only about 5mm of flat surface is left on the cutting edge, and the rest are all beveled, so that iron filings will not accumulate. The second is that scrap knives use forgings, not castings, where iron filings may be brought into the die cavity.

3. Rotary scrap knife

It is difficult for traditional scrap knives to separate trimming and scrap blocking, especially at the junction of scrap knives and trimming edges, where iron scraps are prone to occur. Shanghai Volkswagen requires that a rotary scrap knife must be used for the cover scrap knife. This kind of scrap knife can realize the separation of the two actions of trimming and scrap cutting, and can greatly reduce the occurrence of iron filings.

4. Optimize the mold structure, pay attention to proper emptying

For molds produced by automation or high-speed lines, due to the relatively fast production cycle, if the structure of the stamping mold is unreasonable, negative pressure will occur inside the mold cavity, and the relatively positive air flow outside the mold cavity will suck the iron filings generated by trimming into the mold cavity. , and then cause pressure injury on the surface of the workpiece. It can also be seen at the production site of the precision stamping parts fabrication plant. Although the molds in Japan and South Korea also have iron filings during trimming, they rarely bring them into the mold cavity to crush the parts, while china molds often A large part of the reason why the iron filings are brought into the mold cavity is that the china molds are either not emptied, or “empty and not working”.

5. Install air blowing equipment for improvement

Using the slider angle to control the compressed air The working process of the auxiliary trimming mold blowing equipment is: install the blowing pipe between the upper model surface insert and the scrap cutter, use the press slider angle to control the compressed air valve switch, and then blow Remove iron filings from scrap cutters.

Automotive Sheet Metal Fabrication

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