Knowledge points of stamping process and mold base design, worth collecting

1. What is the function of the drawing threshold (drawing bead) in the cover mold? The function of the drawing sill (drawing bead) is as follows: 1. Increase the feed resistance, make the surface of the drawn part bear sufficient tensile stress, improve the rigidity of the drawn part and reduce the concave surface, distortion, relaxation and caused by springback. Defects such as ripples; 2. Adjust the flow of the material to make the flow resistance of each part in the drawing process uniform, or make the amount of material flowing into the mold suitable for the needs of the workpiece, to prevent the phenomenon of 'more wrinkles, less cracks'; 3. Expand the adjustment range of blank holder force. On the double-action press, adjusting the height of the four corners of the outer slider can only roughly adjust the blank holder force, and cannot completely control the feed amount everywhere to meet the needs of the workpiece. Therefore, it also needs to rely on the blank holder surface and the drawing Deep ribs are used to assist in controlling the pressure everywhere; 4. When there are drawn ribs, it is possible to reduce the requirements for the processing roughness of the blank holder surface, which reduces the difficulty of manufacturing large-scale cover drawing dies; at the same time. Due to the existence of the deep drawing ribs, the gap between the upper and lower blank holders is increased, the abrasion of the blank holders is reduced, and the service life of the mold is improved; 5. The defects of uneven material can be corrected, and the slippage can be eliminated. possibility. This is because when the material flows into the die after being undulated through the drawing bead, it is equivalent to the effect of rolling and leveling. 2. What is the function of the process cut in the large cover piece? When it is necessary to punch out some deep partial protrusions or bulges on the middle part of the cover, in one drawing, the workpiece is often broken due to the inability to obtain material supplement from the outside of the blank. At this time, consider punching process cuts or process holes at appropriate positions in the local protrusion deformation zone, so that the easily ruptured area can be supplemented with material from the deformation zone. 3. How to punch the craft incision? There are two stamping methods for process cuts: 1. Punching out when blanking is used for occasions where the local forming depth is shallow. 2. Cutting out during the deep drawing process. This is a commonly used method. It can make full use of the plasticity of the material, that is, use the radial extension of the material at the beginning of deep drawing, and then cut out the process incision. Using the tangential extension of the material, a greater forming depth can be obtained in this way. When the process hole is cut in the deep drawing process, the process of tearing is often used, and the material is not completely separated, and the waste material of the cut can be removed in the subsequent trimming process. Otherwise, it will be difficult to remove waste from the die. 4. What is the layout principle of the craft incision? The size and shape of the process cut depends on the area in which it is located and the requirements for external supplementary materials. Generally, the following principles should be followed: 1. The cut should be adapted to the shape and contour of the local protrusions to make the material flow reasonably. 2. There should be enough laps between the cuts to make the punch tension material, ensure clear forming and avoid defects such as ripples, so as to ensure that good flanging hole edge quality can be obtained after trimming. 3. The cut part (ie, the opening) of the incision should be adjacent to the edge of the protruding part, or the area that is easy to break. 4. The number of cuts should ensure that the deformation of the material at the protruding part tends to be uniform, otherwise it may not necessarily prevent the occurrence of lines. As shown in the figure below, the original design had only two process cuts on the left and right, but cracks still occurred in the middle. Later, the middle cut (shown by the dotted line) was added to completely avoid the cracking phenomenon. 5. In which stamping production must precision progressive die be used? In mass stamping production, small and medium-sized stamping parts with thinner materials and higher precision must use multi-station precision progressive dies. For larger stamping parts, it is suitable for stamping processing of multi-station transfer dies. 6. What are the requirements for vulnerable parts in precision molds? The precision mold structure is complex, the manufacturing technology requirements are high, and the cost is relatively high. In order to ensure the long life of the whole set of molds, it is especially required to replace the mold parts quickly, conveniently and reliably after they are damaged or worn. Therefore, the important parts of the mold are required to be interchangeable. This kind of mold parts has an interchangeable die, which can be called It is an interchangeable die. 7. What is the significance of the layout design of the precision progressive die? Reasonable layout design can make the processing of each station of the mold coordinated, can greatly improve the utilization rate of materials, manufacturing accuracy, productivity and mold life, and can also reduce the difficulty of mold manufacturing. Therefore, layout design is the most critical comprehensive technical problem in the design of precision progressive die. It is necessary to comprehensively analyze and judge the stamping direction, the number of deformations and the corresponding deformation degree of the part, the possibility of mold structure and the processing technology. , In order to make the layout more reasonable. 8. What is a carrier? When the progressive die is working, the object that carries the blank to each station for various punching and forming processing is called the carrier. The part where the carrier and the blank are connected is called the overlap, and the part where the blank and the blank are connected is called the overlap. At work, the carrier is required to always maintain stable feeding and accurate positioning during dynamic processing, so the carrier is required to have a certain strength. 9. What are the requirements for the mold base of the precision progressive die? M precision progressive die requires high strength, good rigidity and high precision. Therefore, structural steel is usually used as the mold base for the vegetable greenhouse, and its thickness is required to be thicker than the standard mold base. The upper mold base is thicker by 5-10mm, and the lower mold base is thicker by 10-15mm. 10. What are the types of die structure? The common type of die structure is integral type. There are three pieces of block type and block type. In ordinary punching dies, standard concave templates are often used as integral concave molds, and block type and block type concave molds are often used in precision-level molds. Related news: the characteristics of the main materials of stamping parts, the treatment of common problems of stamping parts, the characteristics of scaffolding stamping parts and the importance of inspection, the advantages of metal stamping parts introduce the advantages, procedures and characteristics of stamping parts