The automobile stamping die is an important process equipment in automobile production. Its design and manufacturing time accounts for about two-thirds of the automobile development cycle, and it is one of the main constraints of automobile replacement. The automobile stamping die has the characteristics of large size, complex working surface and high technical standards. It belongs to technology-intensive products. In the past, the structure design of single-process die and compound die was widely used in automobile stamping die. With the improvement of technology and equipment level, multi-position die and progressive die which can reduce cost and improve production efficiency were gradually applied in the design and manufacture of automobile stamping die, and became the development direction of automobile stamping die manufacturing technology.
Stamping die is a tool for processing raw materials, which gives them complete configuration and precise size. It is mainly used for efficient and mass production of related parts and components in industrial products. With the development of modern industry, the application of mould is more and more extensive. In automobile, electronics, instruments, household appliances, aerospace, building materials, motors and communication equipment, about 60% to 80% of parts and components rely on mould processing and forming, so they are called "the mother of industry".
The development of automobile stamping die industry is closely related to the development of downstream automobile industry. The steady and rapid development of downstream automobile industry will greatly promote the development of automobile stamping die industry. Steady and rapid development of automotive industry has created a good environment for the development of automotive stamping die industry. More than 90% of automotive parts need to be formed by die in the production process. It takes about 1,000 to 1,500 sets of stamping dies to make an ordinary car. The steady and rapid development of downstream automobile industry has created a good environment for the development of automobile stamping die industry.
In recent years, with the improvement of people's living standards, the demand for automobiles is also growing. The competition among automobile factories is becoming increasingly fierce. New models with cost competitiveness are continuously invested to seize the market. At the same time, the natural resources such as iron ore and coke used to produce precision stamping parts for automobiles are becoming increasingly tense. Improving the material utilization ratio can not only reduce the manufacturing cost of automobile precision stamping parts and improve the competitiveness of automobile brands, but also conform to the environmental protection concept of energy saving and consumption reduction.
1, mold design optimization, multiple models
When several precision stamping parts are produced simultaneously on a set of dies, one or more small precision stamping parts are produced by using the scrap at the hole of large precision stamping parts, so as to improve the utilization ratio of materials.
The die for the inner panel of B5 type hood and the inner panel of T7 door respectively uses the scrap at the hole of the precise stamping parts of the inner panel of hood and the inner panel of door to stamp out the precise stamping parts of the cover reinforcement plate and the door lock reinforcement plate, avoiding the production of the cover reinforcement plate and the door lock reinforcement plate by using the material alone.
2. Die design optimization and slab combination
In die design, precision stamping parts of left and right symmetrical precision stamping parts are designed to be stamped together. Through process optimization, two precision stamping parts of sheet metal are changed into two precision stamping parts of sheet metal, which reduces the supplementary area of process and improves the utilization ratio of materials.
For MX3 model of left and right rear door exterior panel precision stamping parts die design and M44 model of left and right rear door exterior panel die design comparison. MX3's left and right rear door outer panel stamps a precise stamping part with one sheet metal, and the four directions of the precise stamping parts need process supplementary surface; while M44's left and right rear door outer panel stamps two precise stamping parts with one sheet metal, which is equivalent to reducing one process supplementary surface. By comparison, the material utilization ratio of M44 rear door outer panel is 4.16% higher than that of MX3 rear door outer panel.
For precision stamping parts, the material utilization ratio of the same precision stamping parts reflects the technological level and technical level. Combining with the practical application of stamping field, this paper introduces the methods to improve the material utilization ratio of automobile precision stamping parts from the aspects of process optimization, material size optimization, waste reuse and coil weight improvement. Through the practical application of the above methods, the technology is improved. The technical level provides a reference for the process design of follow-up projects.
There are many ways to improve the material utilization rate. More methods need to be verified by practice. For example, when blanking stamping panels, the existing linear or circular knife should be changed into wave knife. By changing the shape of the slab and shortening the length of the slab, the material utilization rate can be improved. This method needs to calculate the relationship between the investment of the die, the cost of maintenance and the profit after improving the material utilization rate. In a word, the purpose of improving material utilization rate is to reduce the total cost of the whole vehicle. When making the plan of improving material utilization rate, we need to consider the relationship between investment cost and income, taking into account the output of the vehicle.