How to prevent iron filings from trimming of precision stamping dies

Iron filings are generally present when trimming the stamping die, especially around the scrap cutter of the lower die. The iron filings not only seriously affect the product quality and the cleanliness of the mold appearance, but also reduce the production efficiency. To prevent this phenomenon, we can take the following measures to prevent iron filings: 1. Rationalization of the blade gap. The plate is not in conformity and the blade gap is unreasonable. The measure taken is to use the OP10 drawing plate buckle to study and repair the various parts of the edge mold. At the same time, the gap between the upper and lower cutting edges can be adjusted and the depth of penetration can be adjusted. 2. When optimizing the trimming process, in order to improve the quality of the section and the life of the cutting edge, the following three measures can be adopted: (1) The fillet of the upper edge of the trimming should be 3mm larger than the fillet of the trimmed part, so It can ensure that when the upper and lower molds are completely closed, the trimming edge is cut into 1-3mm and transitions slowly. (2) The vertical edge of the trimming edge of the upper die and the vertical edge of the trimming piece are at an angle of 10°. (3) Install guide blocks as much as possible to eliminate the lateral force on the cutting edge. 3. Layout and structure optimization of scrap knives (1) Under the premise of the allowable size of waste conveying equipment and mold structure, the arrangement of scrap knives can be minimized. For example, the Shanghai Volkswagen scrap knives standard clearly states that scrap knives try to avoid. (2) Optimization of scrap knife structure. Comparing the two, there are actually only two differences in Korean scrap knives: one is that only a 5mm plane is left on the cutting edge, and the others are all beveled so that iron filings will not accumulate. The second is that where iron filings may be brought into the mold cavity, the scrap knife uses forgings instead of castings. 4. Rotating scrap knife The traditional scrap knife is difficult to separate trimming and scrap cutting, especially at the junction of the scrap knife and the trimming edge, where trimming iron filings are most likely to be generated. Shanghai Volkswagen requires the use of rotating scrap knives for covering scrap knives. This scrap knives can separate the trimming and scrap cutting actions, which can greatly reduce the generation of iron filings. Structure description: (1) The position of the bolt center point must be higher than the starting point. (2) The ratio of the two lever arms should be L1:L2u003d1:1. (3) The swing blade device should be 5mm above the center line of the rotation point, and the angle X should be 2° larger than the swing knife rotation angle Y. 5. Optimize the mold structure, pay attention to the appropriate emptying of the molds produced by automation or high-speed lines. Because the production cycle is relatively fast, if the structure of the stamping mold is unreasonable, it will cause negative pressure inside the mold cavity and relatively positive airflow outside the mold cavity. The iron filings generated by the edge are sucked into the mold cavity, causing crushing of the surface of the part. It can also be seen in the production site that although the molds in Japan and South Korea also have iron filings during trimming, it is rare that the parts are brought into the cavity and crushed, while the domestic molds often have iron filings. A large part of the reason for the situation of the mold cavity is that the domestic molds are either not empty, or'empty but not through'. 6. Install an air blowing device for improvement. Use the slider angle to control the compressed air. The working process of the auxiliary trimming mold blowing device is: install a blowing pipe between the upper mold face insert and the scrap cutter, and use the press slider The angle controls the opening and closing of the compressed air valve to blow off the iron filings produced by the scrap cutter. In summary, trimming and removing iron filings have a great relationship with trimming mold structure, cutter block layout, trimming cutter block material, hardness, perpendicularity, clearance, production environment, waste discharge, etc. Unreasonable layout of scrap knives in the stamping die design phase and failure of production personnel and tooling maintenance personnel in the mass production phase to strictly follow the production and mold maintenance work instructions will produce iron filings. In addition, the height of the production mold is too low, the waste is not cleaned up in time, and the foreign body is pressed into the mold surface, which causes the upper and lower molds to be out of focus, gnawing the cutting edge, and also produce iron filings. Therefore, reasonable mold structure and cutting edge clearance, as well as standard operating procedures and implementation, play a vital role in eliminating and reducing trimming iron filings and improving mold service life. Recommended article: Discussion on the impact of punching clearance of metal stamping dies on the quality of stamping parts 上一篇：Maintenance essentials of stamping continuous dies