Introduction to multiple drawing
As we all know, when drawing, stamping and drawing products sometimes need to go through multiple drawing processes. Of course, it is better to stretch them once as much as possible. . These tensile forming processes can be divided into several types: tensile processing,’re tensile processing, thinning tensile processing, reverse tensile processing. Please refer to the introduction of these multi-drawing processes by stamping and drawing manufacturers below. 1. Tightening treatment: use the plate pressing device and the punching force of the punch to pull some or all of the flat materials into the cavity of the female die, so that it can form a bottomed container. The side wall of the container is parallel to the stretching direction, which is a simple stretching process. Some need to be expanded to form.
- Redrawing: that is, for products that cannot be finished by deep drawing, semi-formed products after deep drawing need to be stretched again to increase the depth of the formed container.
- Reverse stretching process: reverse stretching the parts stretched in the previous process, the inner side of the workpiece becomes the outer side, and the outer diameter decreases.
- Thinning and stretching process: extrude the formed container into the cavity of the die slightly smaller than the outer diameter of the container with a punch, so that the outer diameter of the container with a bottom becomes smaller and the wall thickness becomes thinner, eliminating the deviation of the wall thickness, and making the surface of the container smooth.