How to ensure the high precision of the inner and outer surfaces of the stretching die?
Publish Time: 2025-06-11
In the field of mold manufacturing, especially in the stretching die used for the production of precision parts such as battery steel shells, the processing accuracy of the inner and outer surfaces is directly related to the quality and consistency of the finished product. In order to ensure that the stretching die can still maintain high-precision geometry and surface quality under complex process conditions, manufacturers strictly control and optimize from multiple aspects such as material selection, processing technology, equipment configuration and subsequent processing.First of all, the selection of high-quality raw materials is the basis for achieving high-precision processing. Stretching dies usually use high-performance cemented carbide as the main material. This material not only has excellent wear resistance and pressure resistance, but also has good thermal stability and chemical inertness. These characteristics make the mold less likely to deform or wear during long-term use, thereby ensuring the geometric accuracy of its key parts such as the inner and outer surfaces. In addition, the uniformity and density of the internal structure of the material also play a decisive role in the final processing effect. Therefore, the material composition, grain structure, etc. need to be strictly screened in the material selection stage.Secondly, advanced processing technology is the key link to ensure the high precision of the inner and outer surfaces. Due to the complex curved surface structure and extremely high tolerance requirements of stretching die, traditional mechanical processing methods often cannot meet the precision requirements of modern manufacturing industry. Therefore, many high-end mold manufacturers have adopted multi-axis linkage CNC machining technology to control the tool path through programming to achieve continuous and smooth cutting of the curved surface. This method can not only accurately restore every detail in the design drawings, but also effectively reduce human errors and improve the consistency of overall processing. At the same time, adding an intermediate heat treatment process between rough machining and finishing can help release the internal stress of the material and prevent minor deformation during subsequent processing, thereby further improving the stability of the curved surface.Furthermore, the application of special processing equipment provides hardware guarantee for high-precision curved surface processing. Modern mold manufacturing workshops are generally equipped with advanced equipment such as high-rigidity and high-stability five-axis linkage machining centers, slow-wire cutting machines, and high-precision EDM forming machines. These equipment have extremely high positioning accuracy and repeatability, and can complete the fine processing of complex curved surfaces within the micron range. Especially when processing the inner cavity or deep hole of the mold, these equipment can also achieve high-quality processing effects in areas that are difficult to reach with traditional methods. In addition, some high-end equipment is also equipped with an online measurement system, which can monitor the size changes in real time during the processing process and automatically adjust the parameters to ensure that the final product fully meets the design requirements.In addition, the control of surface finish is also one of the important indicators for measuring the accuracy of surface processing. Even if the mold has completely qualified dimensions, if there are small bumps or scratches on the surface, it may affect the forming quality and demolding efficiency of the drawn parts in actual use. Therefore, after completing the basic contour processing, it is necessary to further improve the surface quality through finishing processes such as polishing and grinding. Some companies will also use advanced technologies such as electrolytic polishing, laser polishing or superfinishing to make the mold surface reach the mirror level, thereby reducing the friction coefficient, increasing the service life and improving the appearance of the product.It is worth noting that the simulation analysis in the mold design stage also plays an important role in ensuring the high precision of the internal and external surfaces. With the help of CAD/CAM software and finite element analysis tools, engineers can simulate the entire processing process in a virtual environment, predict possible deformation, stress concentration and other problems, and optimize the design plan in advance. This not only improves the success rate of trial production, but also reduces the time waste and cost increase caused by repeated modifications.Finally, a perfect quality inspection system is the last line of defense to ensure that high-precision processing results can be achieved. Each stretching die needs to undergo strict dimensional inspection and geometric tolerance evaluation before delivery. Using high-precision inspection equipment such as three-coordinate measuring machines, optical projectors, and profilometers, the geometric shapes of the inner and outer surfaces of the mold can be fully scanned to ensure that they are highly consistent with the original design model. Only molds that have passed layer-by-layer quality inspection can truly meet customers' stringent requirements for precision and quality.In summary, to ensure the high precision of the inner and outer surfaces of the stretching die, systematic management and refined operations are required from multiple dimensions such as raw materials, processing technology, equipment selection, surface treatment, design simulation, and quality inspection. It is this all-round technical integration and strict control that enables modern stretching dies to maintain excellent performance in the face of high-intensity and high-frequency industrial applications, providing a solid guarantee for the high-quality production of downstream products.
