Die manufacturing and stamping production of the h

Car panel mold manufacturing and stamping production

car body panel mold design

car panel mold is the main mold of car production. Now taking the stamping die of car panel as an example, this paper introduces its design and manufacturing ideas from the following aspects that truly solve the long-standing problems of 3D printing customers:

design principles

the design of car panel die should follow the following basic principles:

(1) the stamping direction must be reasonable. Whether the stamping direction design of car panel is reasonable or not determines whether a satisfactory panel product can be drawn, and directly affects the amount of process supplement, the shape of the pressing surface, the hardness and service life of the die

(2) the determination of the shape of the pressing surface must be effective. The shape of the pressing surface of the panel drawing is the primary condition to ensure that the material does not crack and forms smoothly in the drawing process. In order to achieve this goal, the pressing surface should form a certain inclination angle to reduce the drawing depth, and at the same time, a flat pressing surface should be formed to achieve the best pressing effect. It is also necessary to maintain a certain geometric relationship between the pressing ring and the punch shape, so that the material is always in a tense state during the stretching process, can smoothly cling to the punch, no excess material is allowed to wrinkle, and the best pressing effect is maintained. In order to ensure that the pressing surface is smooth and smooth, so that the raw material flows into the concave mold cavity, the pressing surface shall be free of local bulges, pits and sags. If the pressing surface is the flange of the stretching part itself and there are bulges and depressions on it, the shaping process should be increased. When the included angle between the pressing surface and the stamping direction is greater than 90 °, it will increase the feeding resistance, so it is not desirable

(3) the determination of process supplementary surface must be sufficient. The process supplementary surface is not only the condition to realize stretching, but also the necessary supplement to increase the degree of deformation and improve the rigidity of parts. It will directly affect the stretching and subsequent trimming, shaping, flanging and other processes

(4) the mold design must be planned as a whole. The design of the deep drawing die for car cover parts must be combined with the future process, and the overall planning must be carried out reasonably. The design scheme of multi-stage progressive die should be adopted. On the premise of ensuring the deformation springback and surface quality of the product as much as possible, the number of stages should be reduced, so as to help enterprises reduce the manufacturing cost and maintenance cost of the die and improve the production pace

stamping die design concerns

these concerns must also be paid attention to in the die design of car panel:

(1) fillet and straight line design of stretched parts. When the stretching part has rounded corners and linear parts, set stretching ribs in the linear part to balance the feeding speed; If the stretching rib is set at the shallow part of the straight part of the stretching part, the deep straight part does not need to be set with the stretching rib

(2) design of inner and outer rings of the mold. The fillet and straight-line parts of shallow stretching parts should be set with stretching bars, but only one stretching bar can be set in the fillet part, while the straight-line part can be set with stretching bars; If there are multiple stretching ribs, it should be "loose outside and tight inside", that is, the stretching ribs of the outer ring of the mold are "loose" while the stretching ribs of the inner ring of the mold are "tight", so this purpose can be achieved by changing the height of the stretching ribs

(3) the profile of the tensile reinforcement should be convex concave curve. Width stretching bars shall be set at the convex curve part. But in the concave curve part, there is no need to set tensile reinforcement; The stretching rib or stretching sill should be as close to the fillet of the stretching rib die as possible, which can increase the material utilization rate and reduce the overall dimension of the die, but it should be considered not to affect the strength of the trimming die

manufacturing steps

the manufacturing of car panel mold mainly includes the following steps:

(1) mold conceptual design. Car body is a complex free-form surface assembly, and the conceptual design of panel is generally realized by CAD three-dimensional modeling software. The required analysis data and their relationships are abstracted and summarized, and the basic model after computer data processing is established. Conceptual design is also the data abstraction of objective entities, which reflects the specific attributes of entities and the relationship between entities, so as to abstract specific entities into the data model. Therefore, the relationship between each panel entity and its attributes can be determined through conceptual design. As for the design of the drawing die for car panel, the entity is the object that plays a decisive role in the design process of the drawing die, that is, the data model established from different aspects for the entity

(2) mold entity design. The solid design of the panel is generally realized by CAE finite element analysis and simulation software. The application of CAE technology must pay attention to these points: first, we should fully understand the material properties of the processed panel, such as material brand, material specification, material elongation and maximum developed area, and correctly predict the possible wrinkle, fracture, surface quality, springback and other defects during the stamping of the panel. Secondly, we should fully consider the material properties selected in the physical design of the stamping die for car panels. Food packaging is a very important part of the packaging market, such as material specification, material brand and material strength, and correctly grasp the requirements of the connection mode and connection size between the stamping die and the stamping equipment. Finally, we should fully understand the properties of stamping equipment, such as stamping equipment model, overload protection pressure, clutch pressure, air cushion ejection pressure, mobile working pressure, press stroke distance, etc

(3) mold compliance verification. Mold compliance verification is to verify whether the mold installation size, mold hardness, positioning pin and positioning block position, mold cavity size, etc. meet the requirements of the design drawings, and verify whether the mold meets the requirements of the assembly and adjustment technical conditions specified in the design drawings after assembly, that is, the static verification that the mold has not been installed into the equipment

(4) mold applicability verification. Mold applicability verification is a dynamic verification that after the mold meets the compliance verification, the assembled mold is installed in the specified equipment, and the specified process parameters and batch production capacity are verified according to the specified products. The purpose of applicability verification is to verify whether the mold processing products meet the requirements of product drawings and product assembly performance requirements. Therefore, the applicability verification conclusion should be confirmed by the main users

production organization of car body coverings

taking the roof, the main complex part of car body coverings, as an example, this paper introduces the stamping production line organization of car body coverings

production organization ideas

the ideas of stamping production line design of car enterprises can be summarized as follows:

(1) the production efficiency of stamping equipment for car panels should be maximized. In order to achieve the purpose of optimizing the configuration of stamping equipment for car panels, car enterprises must comprehensively consider the use performance, scope of use, use and maintenance of production equipment and rapid die replacement accessories. Therefore, when designing the car panel stamping production line, enterprises should consider the stock of existing stamping equipment and the increment of new fixed assets together, so as to maximize the production efficiency of fixed assets

(2) feasibility research should be done in advance. When introducing the stamping line and its related equipment configuration, car enterprises should not only prevent the introduction of outdated equipment, but also consider that the introduced technology and equipment should conform to the national conditions, the actual use ability of the enterprise, and meet the requirements of different product varieties, product specifications and product series

(3) the quality characteristics of car stamping panels should be fully studied. The establishment of the car panel inspection project is the basis of quality control. There are two bases and two principles for the establishment of the inspection project: the first basis is that after the formation of the body panels, the measurement points and assembly points determined by the user must be taken as the product measurement benchmark; the second basis is that after the formation of the body panels, the minimum deformation point must be taken as the product measurement benchmark; The first principle is to determine the measurement items of each panel of the car body, which must be determined according to the key characteristics and process characteristics of each panel; The second principle is that the measurement of body panels must be the fastest and most accurate measurement method. In other words, the forming and stretching quality control requirements of car body panels are different, so the determination of various panel testing items and the allocation of testing instruments must be aimed at the special requirements that affect product performance and material forming and stretching

(4) the coordination of auxiliary equipment to the whole stamping production line should be considered as much as possible. When designing the car stamping line, enterprises should first consider the configuration of operating manipulator, rapid die change accessories and transportation capacity of the car stamping line to meet the production capacity requirements of various products, so as to achieve smooth product circulation, reduce die change time and reduce handling volume, and have corresponding product turnover sites; Secondly, we should try our best to use logistics transmission line to ensure the coordination of the whole production line; Finally, in order to ensure the quality of car panel products, the configuration of auxiliary processing systems such as stamping die cleaning or die refurbishment should be fully considered

production organization of the production line

the production organization of the stamping production line of the product is introduced with the example of car four doors and two covers

(1) preparation of stamping raw materials. The main tasks for the effective implementation of stamping raw materials preparation for car panels are as follows: first, determine the area of stamping raw materials preparation area, corresponding identification and corresponding transportation equipment according to the production capacity of the enterprise; The second is to verify the material brand, material specification, product batch number and product quantity according to the production order issued by the production department; Finally, fill in the "product task flow card" designed by the process department, and send the prepared stamping raw materials and the completed "product task flow card" to the stamping production line for confirmation

(2) production organization of stamping production line. Panel stamping process is generally determined according to the complexity of the product. The stamping process of the inner panel of the left/right front door of the car is bilateral LEGO. At present, it is in Jiaxing, China. There are six production processes: repair and extension, re drawing + trimming and punching + side trimming and punching, trimming and punching, flanging and punching, punching + side punching + side trimming and shaping. The production organization of the stamping production line is the key to effectively realize the normal production of the production line. Therefore, the production organization of panel stamping production line must pay attention to these points: the first is the standard adjustment of stamping equipment. The equipment parameters of each stamping equipment should be adjusted correctly according to the requirements of the product stamping process card specified in each process. The adjustment parameters include the number of slider clamping devices, the closing height of the slider, the closing height of rare earth resources, the pressure of the balance cylinder, the pressure of the booster cylinder, the working speed, the return speed of the slider, etc. at the same time, the auxiliary equipment used with each stamping equipment must be adjusted in a standardized manner, Such as the adjustment of the motion track of the working manipulator and the driving speed of the front and rear automatic feeding mechanism; Finally, the correct adjustment of the stamping die position. For the correct adjustment of the position of the stamping die, attention should be paid to the adjustment of the number of die supporting parts, the number of lower die pressing plate bolts, die locating pins, the position of the air jacking rod, the pressure of the upper and lower air cushions and the number of air cushion jacking

(3) regular inspection of stamping production line. The regular inspection of stamping production line is to check the correctness of parameters such as overload protection of production equipment and auxiliary equipment, batching clamping force, clutch opening pressure, etc; The second is to check the stability of the physical quality of the product. The inspection items include material defects, hidden injuries, cracks, trimming burrs, holes, burrs, galling, slip marks, wrinkles, pockmarks, etc