Stamping process and mold frame design knowledge points
Release date: 2018-07-02 15:24:01 Visits: 1249
1. What is the role of deep drawing 拉 (draw rib) in the mold of the cover piece?
The effect of deep drawing (draw ribs) is as follows:
1. Increase the feed resistance so that the surface of the deep drawing member is subjected to sufficient tensile stress, increase the rigidity of the deep drawing member and reduce defects such as concave surface, distortion, slack and ripple caused by rebound;
2. Adjust the flow of the material so that the flow resistance of each part during the drawing process is uniform, or the amount of the material flowing into the mold is suitable for the needs of the workpiece, and the phenomenon of "more wrinkles and less cracking" is prevented;
3. Expand the adjustment range of the blank holder force. On the double-action press, adjusting the height of the four corners of the outer slide can only roughly adjust the blanking force, and can not completely control the feeding amount everywhere to meet the needs of the workpiece, so it is also necessary to press the edge and pull Deep ribs to help control the pressure everywhere;
4. When there is a draw rib, it is possible to reduce the processing roughness of the presser face, which reduces the difficulty in manufacturing the large-size cover drawing die; Due to the presence of the draw ribs, the gap between the upper and lower press faces is increased, so that the wear of the presser face is reduced, and the service life of the die is improved;
5. Correct defects in material irregularities and eliminate the possibility of slippage. Because the material flows into the die after the undulations are generated by the draw ribs, it is equivalent to the effect of the roll leveling.
2. What is the role of the process cut in the large cover?
When it is necessary to punch out some of the deeper local protrusions or bulges on the middle portion of the cover member, in one deep drawing, partial cracking of the workpiece is often caused by the inability to replenish the material from the outside of the blank. At this time, it is conceivable to punch out the process slit or the process hole at a proper position of the local protrusion deformation zone, so that the easily broken region is replenished from the inside of the deformation zone.
Third, how to punch the process cut?
There are two types of stamping processes for process cuts:
1. This method is used when blanking is used for occasions where the local forming depth is shallow.
2. Cutting out during drawing is a common method that takes full advantage of the plasticity of the material, ie the use of the radial extension of the material at the beginning of the drawing and then the cutting of the process. The tangential extension of the material is utilized so that a greater depth of formation can be obtained. When the process hole is cut out during the drawing process, the tearing process is often used, and the material is not completely separated, and the waste of the slit can be cut off in the subsequent trimming process. Otherwise, it will create difficulties in removing waste from the die.
What is the principle of the layout of the process cut?
The size and shape of the process cut depends on the area in which it is located and the requirements for its outward replenishment. Generally follow the following principles:
1. The incision should be adapted to the shape profile of the local protrusion to allow the material to flow reasonably.
2. There should be enough lap joints between the slits so that the punch can tension the material to ensure clear shape and avoid defects such as corrugations. This ensures good quality of the flanged edge after trimming.
3. The cut portion (ie, the opening) of the slit should be adjacent to the edge of the raised portion or the area that is easily broken.
4. The number of slits should ensure that the deformation of the material at the protruding parts tends to be uniform, otherwise the grain formation may not be prevented. As shown in the figure below, the original design has only two left and right process cuts, and cracks still appear in the middle. Later, the middle cut (shown by the dashed line) is added to completely eliminate the crack phenomenon.
5. In which stamping production must use precision progressive die?
In large-volume stamping production, small and medium-sized punching parts with thinner materials and higher precision must use multi-station precision progressive die. For larger stampings, it is suitable for stamping of multi-station transfer molds.
6. What are the requirements for consumable parts in precision molds?
The precision mold has a complicated structure, high manufacturing technology requirements, and relatively high cost. In order to ensure a high life of the whole pair of molds, it is especially required to replace the mold parts after damage or wear, which is quick, convenient and reliable. Therefore, it is required that the important parts of the mold are interchangeable. The mold parts have interchangeable dies, which can be called For the interchangeability of the 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, which can greatly improve the material utilization rate, manufacturing precision, productivity and mold life, and also reduce the manufacturing difficulty of the mold. Therefore, layout design is the most critical comprehensive technical problem in precision progressive die design. It is necessary to comprehensively analyze and judge the stamping direction, the number of deformations and the corresponding degree of deformation, the possibility of mold structure and the processing technology. In order to make the layout more reasonable.
Eight, what is the carrier?
When working in a progressive die, the object that carries the blank to each station for various blanking and forming operations is called a carrier. The portion of the carrier that is joined to the blank is referred to as a lap, and the portion of the blank that is joined to the blank is referred to as a lap. In the work, in the dynamic processing, the carrier is required to keep the feeding stable and the positioning is accurate, so the carrier is required to have a certain strength.
9. What are the requirements for precision molds for mold bases?
M precision progressive die requires high strength, good rigidity and high precision. Therefore, structural steel is usually used as the mold base, and the thickness requirement is thicker than the standard mold base. The upper mold base is thickened by 5 to 10 mm, and the lower mold base is thickened by 10 to 15 mm.
10. What types of die structures are there?
Common types of die structures are monolithic. In the ordinary die, the standard concave template is often used as the integral concave die. In the precision die, the block type and the block type die are often used.
The effect of deep drawing (draw ribs) is as follows:
1. Increase the feed resistance so that the surface of the deep drawing member is subjected to sufficient tensile stress, increase the rigidity of the deep drawing member and reduce defects such as concave surface, distortion, slack and ripple caused by rebound;
2. Adjust the flow of the material so that the flow resistance of each part during the drawing process is uniform, or the amount of the material flowing into the mold is suitable for the needs of the workpiece, and the phenomenon of "more wrinkles and less cracking" is prevented;
3. Expand the adjustment range of the blank holder force. On the double-action press, adjusting the height of the four corners of the outer slide can only roughly adjust the blanking force, and can not completely control the feeding amount everywhere to meet the needs of the workpiece, so it is also necessary to press the edge and pull Deep ribs to help control the pressure everywhere;
4. When there is a draw rib, it is possible to reduce the processing roughness of the presser face, which reduces the difficulty in manufacturing the large-size cover drawing die; Due to the presence of the draw ribs, the gap between the upper and lower press faces is increased, so that the wear of the presser face is reduced, and the service life of the die is improved;
5. Correct defects in material irregularities and eliminate the possibility of slippage. Because the material flows into the die after the undulations are generated by the draw ribs, it is equivalent to the effect of the roll leveling.
2. What is the role of the process cut in the large cover?
When it is necessary to punch out some of the deeper local protrusions or bulges on the middle portion of the cover member, in one deep drawing, partial cracking of the workpiece is often caused by the inability to replenish the material from the outside of the blank. At this time, it is conceivable to punch out the process slit or the process hole at a proper position of the local protrusion deformation zone, so that the easily broken region is replenished from the inside of the deformation zone.
Third, how to punch the process cut?
There are two types of stamping processes for process cuts:
1. This method is used when blanking is used for occasions where the local forming depth is shallow.
2. Cutting out during drawing is a common method that takes full advantage of the plasticity of the material, ie the use of the radial extension of the material at the beginning of the drawing and then the cutting of the process. The tangential extension of the material is utilized so that a greater depth of formation can be obtained. When the process hole is cut out during the drawing process, the tearing process is often used, and the material is not completely separated, and the waste of the slit can be cut off in the subsequent trimming process. Otherwise, it will create difficulties in removing waste from the die.
What is the principle of the layout of the process cut?
The size and shape of the process cut depends on the area in which it is located and the requirements for its outward replenishment. Generally follow the following principles:
1. The incision should be adapted to the shape profile of the local protrusion to allow the material to flow reasonably.
2. There should be enough lap joints between the slits so that the punch can tension the material to ensure clear shape and avoid defects such as corrugations. This ensures good quality of the flanged edge after trimming.
3. The cut portion (ie, the opening) of the slit should be adjacent to the edge of the raised portion or the area that is easily broken.
4. The number of slits should ensure that the deformation of the material at the protruding parts tends to be uniform, otherwise the grain formation may not be prevented. As shown in the figure below, the original design has only two left and right process cuts, and cracks still appear in the middle. Later, the middle cut (shown by the dashed line) is added to completely eliminate the crack phenomenon.
5. In which stamping production must use precision progressive die?
In large-volume stamping production, small and medium-sized punching parts with thinner materials and higher precision must use multi-station precision progressive die. For larger stampings, it is suitable for stamping of multi-station transfer molds.
6. What are the requirements for consumable parts in precision molds?
The precision mold has a complicated structure, high manufacturing technology requirements, and relatively high cost. In order to ensure a high life of the whole pair of molds, it is especially required to replace the mold parts after damage or wear, which is quick, convenient and reliable. Therefore, it is required that the important parts of the mold are interchangeable. The mold parts have interchangeable dies, which can be called For the interchangeability of the 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, which can greatly improve the material utilization rate, manufacturing precision, productivity and mold life, and also reduce the manufacturing difficulty of the mold. Therefore, layout design is the most critical comprehensive technical problem in precision progressive die design. It is necessary to comprehensively analyze and judge the stamping direction, the number of deformations and the corresponding degree of deformation, the possibility of mold structure and the processing technology. In order to make the layout more reasonable.
Eight, what is the carrier?
When working in a progressive die, the object that carries the blank to each station for various blanking and forming operations is called a carrier. The portion of the carrier that is joined to the blank is referred to as a lap, and the portion of the blank that is joined to the blank is referred to as a lap. In the work, in the dynamic processing, the carrier is required to keep the feeding stable and the positioning is accurate, so the carrier is required to have a certain strength.
9. What are the requirements for precision molds for mold bases?
M precision progressive die requires high strength, good rigidity and high precision. Therefore, structural steel is usually used as the mold base, and the thickness requirement is thicker than the standard mold base. The upper mold base is thickened by 5 to 10 mm, and the lower mold base is thickened by 10 to 15 mm.
10. What types of die structures are there?
Common types of die structures are monolithic. In the ordinary die, the standard concave template is often used as the integral concave die. In the precision die, the block type and the block type die are often used.
