Quality improvement measures and reasonable selection of equipment for metal sta
≪ 1> Quality improvement measures for stamping parts
Stamping technology can be divided into two categories: separation process and forming process. The separation process includes cutting, punching, trimming, etc., while the forming process includes stretching, bending, flanging, etc. Propose detailed preventive measures and solutions for possible wrinkling, cracking, and rebound defects in each process.
1. Wrinkles and wrinkles
The fundamental reason for wrinkling defects is that the sheet metal is subjected to compression, and when the primary and secondary stresses in the plane direction reach a certain level, the thickness direction becomes unstable. According to the different causes of wrinkle formation, it can be divided into two types: one is the accumulation of wrinkles caused by excessive material entering the cavity of the concave mold; The two types are instability wrinkling caused by instability in the thickness direction of the sheet metal or uneven tensile stress. To address this defect, the specific solution is as follows: (1) From a product design perspective: minimize the height of the flange as much as possible; Connect the areas of drastic changes in shape in a smooth state; For areas of the product that are prone to wrinkling, suction molding can be appropriately added; (2) Starting from the design of stamping process: increase the edge pressure and control the feeding speed; Add circular or square drawing ribs to the process supplement; Add forming processes within a reasonable range; (3) For the selection of stamping materials: While meeting product performance requirements, for some parts that are prone to wrinkling, materials with good formability should be selected.
2. Cracking
The fundamental reason for the formation of cracking defects is that during the stretching process of the material, the strain exceeds it, and a more intuitive manifestation is the visible cracks on the surface of the workpiece. It can usually be divided into three types: one is caused by insufficient tensile strength of the material, and the reason for fracture is generally due to excessive local stress at the rounded corners of the convex and concave molds; The two types are due to insufficient deformation of the material, such as cracking at sharp points; Three types of cracks are caused by impurities in the material. Therefore, in order to prevent fracture defects, a fundamental measure is to reduce stress concentration. The specific plan is as follows: (1) Choose a reasonable billet size and shape; (2) Adjust the parameters of the drawstring to prevent cracking caused by excessive swelling force; (3) Increase process incisions, ensure reasonable material flow, and achieve uniform deformation; (4) Change lubrication conditions, reduce friction, and increase feed rate; (5) Reduce the edge pressure or use variable edge pressure to control the feeding resistance; (6) Using materials with good ductility and formability to reduce cracks.
3. Rebound
The vast majority of stamped parts will produce rebound defects, and the fundamental reason for rebound can be summarized as follows: after the part is deformed by stamping, the material is loaded due to elasticity, resulting in local or overall deformation. Stamping materials, pressure levels, and mold conditions can all affect springback. For rebound defects, the solution is as follows (1) Compensation method, which refers to pre making a slope on the mold equal to the rebound amount of the stamped part after bending forming, to compensate for the rebound amount of the workpiece after forming. The size of the rebound amount to be compensated in this method is mainly determined based on manual experience estimation or CAE numerical simulation analysis results; (2) Bending method: Apply tension while bending the sheet metal to make the stress distribution inside the sheet metal more uniform, thereby reducing the amount of rebound; (3) Local compression method: Transforming the deformation zone into a stress state of triaxial compression, fundamentally changing the properties of elastic deformation; (4) By locally reinforcing and other methods to increase stiffness, the stiffness of stamped parts can be improved and deformation reduced.
≪ Two> Reasonable selection of equipment for stamping parts
Based on the analysis of various aspects such as punching force, mold structure, and height in the actual manufacturing process, the application of existing manufacturing facilities is closely related to the design of molds. It is necessary to develop relevant design requirements and determine the type of equipment based on the relevant design.
If the equipment used for manufacturing is small and the calculation values related to stamping are small, but the specifications required for the mold are large, the facilities that need to be selected are relatively large.
Select equipment that meets the height and leakage hole size based on the actual specifications of the mold. The design of the mold needs to pay attention to these aspects: first, balance the punching pressure and the mold; Next, calculate the data and calibrate the relevant power; In the later stages of bending and other processes, in order to address quality issues with the parts, it is necessary to calibrate the manufacturing process so that the manufacturing of automotive parts can proceed smoothly.
The body, internal structure, and seats of a car are all made of steel plates through stamping technology. Automotive metal stamping parts; The manufacturing process is the basic technical capability of automobile production, which then determines various aspects such as the cost-effectiveness and appearance of the automobile body. The most intuitive part of a car's composition is its body, which is also an important component of the car. The manufacturing process of automobiles is directly related to their service life, and improving the stamping manufacturing process of automotive parts is an important competitive advantage in the automotive industry.
