How to solve the problem of skipping waste in high-speed precision stamping parts

The high-speed precision stamping parts designed by the mold designer, whether the product can be punched, whether there will be problems with the mold, requires actual mold trial inspection. Generally, there will be some problems in the trial of new molds, which requires the on-site master fitter to repair the mold. However, some problems are completely avoidable or predictable. For example, in high-speed molds, mold trial is a common mold trial problem 'jumping scrap'. The so-called skipping waste refers to the phenomenon that when the mold is running at high speed, it should be punched to the lower mold by the punch, and the waste falling through the waste hole of the lower mold is brought to the die surface by the punch to affect production. Once the mold has skipped scraps, the scraps that are brought up will damage the strips or punches and knife edges, affect the quality of stamping parts, reduce the service life of the mold, and reduce the production efficiency. This is the most common and most worrying 'taboo' for high-speed molds. '. Reasons for the formation of skipping scrap 1. The reason for the occurrence of skipping scrap is that during the high-speed stamping process of the die, the high punching speed (above 800m/s) and the punching oil and other factors in the punching process make the punch and the scrap fit together. A partial vacuum is formed in the position, especially when the stamping material is very thin, because the scrap itself is light in weight, and the friction with the knife edge is very small. When the punch completes the punching process, the waste is brought onto the die surface along with the punch. , And form the phenomenon of skipping waste. 2. Factors that affect skipping scraps There are many factors that affect skipping scraps, such as: punch corners, passivation or excessive amount of punching oil, thin materials, and punches that are too short for effective punching, etc., can all cause skipping scraps. 3. Methods to prevent skipping waste 1. Reduce the contact area a between the punch and the product, and slot the punch and product contact surface. b. For punches with large but irregular shapes, a hole can be dug in the middle of the punch to reduce the contact area. c, the punch is shaped like a grinder. d. When designing the mold, add a blowing hole in the middle of the punch to prevent material from being carried by blowing. e. If the punch material is SKD11, a spring pin can be added to the punch in the design to prevent chip jumping. 2. Increase the friction of the blade against the scrap a. For inserts or combined blades, a drape needle can be used to 'cover' a place about 1mm below the blade to increase the friction of the scrap in the blade. b. For manufacturable auxiliary steps, such as side edge, cutting edge of the material distribution station, etc., the shape of the waste can be appropriately complicated to increase the clamping force of the waste in the die, thereby preventing chip jumping. 3. Other a. Use a vacuum cleaner to suck away the waste material to prevent it from jumping. b. The punches and knife edges must be kept sharp, and the appropriate amount of punching oil added will help prevent skipping waste. In any case, there are many reasons that affect the skipping of high-speed precision stamping parts, and there are many ways to prevent it. The above content is just some effective methods summarized by the author in actual work and study.