The design work before stamping of automobile parts should be done well

2020-04-06 15:16:58

As we all know, there are hundreds of parts, big and small, on the car, and the stamping parts of auto parts account for a large part. Auto parts metal stamping is a kind of production technology which uses the power of conventional or special stamping equipment to directly deform the sheet metal in the die, so as to obtain a certain shape, size and performance of product parts. In order to get a good stamping product, it is necessary to do a good job of design before stamping.

The processing of automobile parts stamping is a kind of metal cold deformation processing method, which is one of the main methods of metal plastic processing (or pressure processing), and also belongs to the material forming engineering technology. Before the design, we should pay more attention to get good results.

1. Under the condition of normal use, the requirements of dimensional accuracy grade and surface roughness grade shall be lower as far as possible, which is conducive to product exchange, reducing waste products and ensuring product quality stability.

2. It can meet the requirements of product use and technical performance, and is easy to assemble and repair.

3. The simple shape and reasonable structure are conducive to the simplification of die structure and process quantity, that is, to complete the processing of the whole part with less and simple stamping process, to reduce the use of other methods for processing, to facilitate the stamping operation, to facilitate the organization of mechanized and automated production, and to improve labor productivity.

4. The design of stamping parts of hardware automobile should be conducive to the use of existing equipment, process equipment and process flow as much as possible, and to the extension of die service life.

5. It is beneficial to improve the utilization rate of metal materials, reduce the variety and specification of materials, and reduce the consumption of materials as much as possible. If allowed, low-cost materials shall be used to make the parts free of scrap and less scrap blanking.

According to the description of the slip line method, only the stamping parts with relatively simple shape can establish the corresponding slip line field. And only under the very simple boundary condition can the mathematical expression of the slip line be given from the solution of the characteristic square. In general, it is necessary to use the numerical integration of the characteristic equation to obtain the approximate slip line field according to the given boundary conditions and point by point recurrence. This method is based on the transformation of the differential equation of the characteristic line as the finite difference relation and the characteristics of the slip line as the basis. Therefore, the slip line method is difficult to be applied in practical production because of its complicated mathematical operation.

Geometric mapping. They think that the mapping from workpiece to billet can be realized according to some assumptions without considering the boundary conditions such as deformation stress, stress-strain relationship and boundary friction. Firstly, the wooden model is meshed, and the position coordinates of the nodes are obtained by the coordinate measuring instrument. Or the CAD model can directly divide the grid in the computer. Assuming that the thickness of the workpiece is constant during the forming process and the area of the mesh before and after the deformation is constant, the three-dimensional space mesh is mapped to the two-dimensional plane, so that the initial blank shape and the stress distribution of the workpiece can be deduced.

Simulation method. The simulation method is to simulate the metal flow of sheet metal flange under certain assumptions, according to the similarity of mathematical description of many physical problems, through the mathematical similarity theory, using the model composed of other physical media. Laplace and Poisson equations are widely used in sheet metal forming.