Estimated reading time: 5 minutes
Stamping is a leading process in the automobile manufacturing process. The automobile stamping workshop is responsible for the storage of raw material coils and sheets; the uncoiling and shearing of coils; the shearing of sheets; the stamping production of large, medium, and small stamping parts of various models; the storage of stamping parts; waste treatment and equipment, molds daily repair and maintenance tasks.
1. Stamping Workshop Process
Raw materials (sheet and coil) storage→uncoiling line→cleaning and oiling of large pieces, uncoiling and cutting of small pieces→stamping production line→installation of molds and commissioning of the first qualified piece→putting into mass production→rust prevention of qualified pieces→storage.
2. The Concept And Characteristics of Cold Stamping
- Cold stamping is a pressure processing method that uses a die installed on a press to apply pressure to the material at room temperature to cause separation or plastic deformation to obtain the required parts.
- Characteristics of cold stamping: regular product size, high precision, lightweight, rigidity, good interchangeability, high efficiency, low consumption, simple operation, and easy automation.
3. Classification of The Basic Process of Cold Stamping
Cold stamping can be summarized into two categories: forming process and the separation process.
- The forming process is to obtain a stamping part of a certain shape and size by plastically deforming the blank without breaking.
The forming process is divided into drawing, bending, flanging, shaping, etc.
Drawing: A stamping process that uses a drawing die to turn a flat blank (process piece) into an open hollow piece.
Bending: A stamping method that bends sheets, profiles, pipes, or bars into a certain angle and curvature to form a certain shape.
Flanging: It is a stamping forming method that turns the sheet material into a vertical edge along a certain curvature on the flat part or curved part of the blank.
- The separation process is to separate the sheet metal according to a certain contour line to obtain a stamping part with a certain shape, size, and quality of the cut surface.
The separation process is divided into blanking, punching, corner cutting, trimming, etc.
Blanking: The materials are separated from each other along the closed curve, and when the part inside the closed curve is used as a blanking part, it is called blanking.
Punching: The material is separated from each other along the closed curve, and when the part outside the closed curve is used as a punching part, it is called punching.
4. The Name And Code of Each Process
|Process name||Drawing||Trimming||Piercing||Edge finishing||Forming||Flanging||Cutting||Blanking||Flip hole||Wedge punching|
Among the parts produced in the stamping shop, some belong to the cover parts, such as the engine hood outer panel, roof cover, car door, and so on.
5. Requirements for Covering Parts
- The size and shape should conform to the inspection fixture and the sample that has been welded and assembled.
- Good surface quality. Defects such as ripples, wrinkles, dents, scratches, abrasions, and indentations are not allowed on the surface of the outer cover (especially the outer cover of a car). The ridges should be clear and straight, and the curved surfaces should be smooth and evenly transitioned.
- Good rigidity. During the forming process of the covering part, the material should have sufficient plastic deformation to ensure that the part has sufficient rigidity.
- Good craftsmanship. The cover art should have good stamping process performance and welding process performance to reduce the production cost of stamping and welding. The stamping process mainly depends on whether the various processes, especially the drawing process can be carried out smoothly and whether the product can be stabilized.
6. Composition of Stamping Die
- Working Parts
Including parts such as punch and die.
- Positioning Parts
It mainly includes retaining pins, positioning pins, side blades, and other parts.
- Pressure, Unloading, And Jacking Parts
It mainly includes an unloading plate, ejector, pneumatic ejector, and other parts.
- Guide Parts
Including guide post, guide sleeve, guide plate, and other parts.
- Support Parts
It includes parts such as upper and lower templates and punch and concave die fixing plates.
- Fastening Parts
Including hexagon socket screws, discharge screws, and other parts.
- Cushioning Parts
Including unloading spring, polyurethane rubber, nitrogen cylinder, etc.
There are mainly safety side pins, safety screws, work limiters, storage limiters, loading and unloading racks, waste chutes, lifting rods, lifting lugs, etc. Safety side pin: the main function is to prevent the fastening screws of the upper mold pressing plate from loosening or breaking, causing the pressing plate to fall, resulting in heavy losses of personnel and tooling. Storage limiter: the main function is to prevent the elastic components of the mold from being under pressure for a long time and to prevent the long-term contact of the cutting edge from affecting the life of the cutting edge. (Usually, polyurethane rubber is used). Work limiter: the main function is to limit the depth of the punch and die.