1. Cold stamping: refers to a pressure processing method that obtains the required parts by applying pressure to the material at a normal temperature by using a die mounted on the press to cause separation or plastic deformation.
2. Features of cold stamping:
Stable product size, high precision, light weight, good rigidity, good interchangeability, high efficiency, low consumption, easy operation, easy automation
Cold stamping is generally divided into two categories: separation process and forming process
1. The separation process is to form a stamping of a certain shape, size and cut surface quality by separating the sheets according to a certain contour line.
2. The forming process is a stamping in which the blank is plastically deformed without breaking, thereby obtaining a certain shape and size.
The process supplement section should consider the following three requirements:
1. Delayed feed conditions
2. The shape and position of the binder surface.
3. The position of the trimming line and the way of trimming.
There are two types of binder surfaces:
1. It consists of the flange surface of the workpiece itself;
2. It consists of a supplement to the process;
Formulate the basic principles of the binder surface:
1. In order to reduce the depth of drawing, the pressing surface can be designed into a certain curved shape to bend the blank into a certain shape before drawing. However, the shape of the pressing surface should be as simple and smooth as possible to prevent the blank from wrinkling during the pressing process, and to facilitate the flow of the material into the concave mold during the drawing.
2. Between the shape of the pressing surface and the shape of the punch, a certain geometric relationship should be maintained - to ensure that the blank is in tension during the drawing process, and can smoothly and gradually adhere to the punch to prevent wrinkles. To this end, the following relationship must be satisfied: the length of the binder surface < the length of the surface of the punch surface
The difference between drawing and forming
1. When the forming depth of the part is greater than 10MM, it is better to use the drawing method to avoid the phenomenon of extrusion.
For less than 10, it can be considered to be used for molding. At the same time, in order to avoid stacking, the process gap is usually added.
2. Drawing generally requires a complete process replenishment surface and a binder surface, and is a closed geometry.
But molding can only be made locally, not all closed
3. The same material grade of the same part, the product obtained by drawing or forming process, the former in terms of rigidity
Stronger than the latter.
4. Parts are close to closed parts, preferably drawn, and open can be molded.
Reasons for adding blanking process
A. When the difference between the widths of different parts of the same part is more than 30%, consider adding the blanking die, otherwise it will be difficult to form.
B, improve material utilization
C. The sheet before molding has a large area without forming part of the formed part.
The difference between unwinding and blanking
A. The parts of the product are large, and the manual operation of the parts with high labor intensity is as close as possible.
B. Compared with the ordinary blanking die, the parts that can improve the material utilization rate are unrolled.
C. The width of the coil required for the blank is too small or too wide to be used for unwinding and blanking.
A common blanking mode is required.
D, parts routing planning parts produced on the automation line, the best blanking die