Processing requirements for precision drawing stamping parts

Precision drawing stamping parts are common accessories in hardware tools, so what are its processing requirements?

1. The shape of the precision drawing stamping parts should be as simple and symmetric as possible: in the circumferential direction, the axisymmetric drawing parts will be uniformly deformed, the mold at this time is also easier to process, and the manufacturability at this time It is also the best. For stretched parts of other shapes, try to avoid sharp contour changes. For example, the rear cover of the car muffler, under the premise of ensuring the requirements of use, after the simplified shape, will make the production process from multiple processes to one or two processes, and the material consumption will also be reduced by half. 2. The size ratio of each part of precision drawing stamping parts should be appropriate: the design of flanges and deep drawing parts should be avoided as much as possible, because such workpieces require more stretching times. For example, the upper and lower dimensions of the workpiece are too different to meet the requirements of the drawing process. If you want to make it meet the requirements, you can divide it into two parts, process and manufacture them separately, and then connect them. If the cavity of the workpiece is not deep, but the flange diameter is large, the manufacturing difficulty is also great, and annealing treatment is needed in the middle. If the flange diameter is reduced, intermediate annealing can be omitted. The outer profile of the flange of the workpiece is best to be similar to the profile shape of the deep drawing part. If the width of the flange is inconsistent, it will not only be difficult to stretch, but also need to add processes, but also need to relax the trimming margin and increase metal consumption. 3. The fillet radius of the precision drawing stamping parts should be appropriate: in order to facilitate the forming and reduce the number of drawing times, the fillet radius of the drawing parts should be increased as much as possible. The corner radius between the bottom and the wall of the stretched part, the flange and the wall, and the four walls of the rectangular part should meet the requirements. 4. The unevenness of the thickness of precision drawing stamping parts should be considered: the inner and outer walls of the workpiece that is stretched multiple times or the flange surface of the flanged drawing parts should be allowed to have the impressions produced during the drawing process. Only when the workpiece has special requirements, can we use the method of shaping or rushing to eliminate these marks. 5. The hole positions on the precision drawing stamping parts should be arranged reasonably: the hole positions on the drawing parts are set on the main structural surface to keep it on a plane, or the hole wall is perpendicular to the plane for punching Finished in one process at the same time as trimming. 6. Selection of drawing oil: In the selection of drawing oil, in addition to the lubricity and cooling properties of the drawing oil, the rust resistance, cost and easy maintenance of the drawing oil should also be considered. . Stretching oil is easy to choose base oil with relatively low viscosity to add anti-friction additives, so that it can achieve lubrication and anti-friction, but also has good cooling and easy filtering. However, the problem of drawing oil is that it has low flash point, high temperature during stamping and forming, easy to deform, high risk factor, and fast volatilization, and the user's use cost is correspondingly high. Therefore, when conditions permit, try to choose compressive resistance Stretching oil with high abrasiveness.

7. The dimensional accuracy of precision drawing stamping parts should not be too high: the manufacturing accuracy of drawing parts includes the accuracy of the diameter direction and the accuracy of the height direction. In general, the precision of precision drawing stampings should not exceed the specified value. The size on the product drawing needs to indicate the guaranteed outer size or the inner cavity size, and the inner outer size cannot be marked at the same time.