Sheet metal forming process worth learning

1. Due to extrusion, the metal material will bulge on both sides of the sheet metal corner after bending, resulting in a width greater than the original size. The size of the bulge is related to the thickness of the material used. In order to avoid this phenomenon, make a semicircle on both sides of the bending curve in advance. The diameter of the semicircle is preferably 1.5 times the material thickness. The same method can be used to deal with the design of edge materials.

2. When bending the metal plate, the internal R angle is preferably greater than or equal to 1 / 2 of the material thickness. If the R angle is not made, the right angle will gradually disappear. After repeated drilling, the R angle will naturally form, and then the length of one or both sides of the R angle will be slightly longer.

3. The metal plate is easy to deform after bending. In order to avoid deformation, an appropriate amount of 45 degree reinforcing agent can be added to the bending part to increase the strength based on the principle of non-interference with other parts.

4. Generally, when the sheet metal part is long and narrow, it is not easy to maintain its straightness, and it is easier to deform after being stressed. Therefore, we can fold an L-shape or fold both sides into a ㄇ - shape to maintain its strength and straightness, but usually L-shape and ㄇ - shape cannot be connected from beginning to end. What should I do when some factors interrupt? At this time, we can make appropriate ribs to increase its strength.

5. At the turning point between the plane and the bending surface, it is better to have a narrow hole or side opening back to the back of the bending, otherwise burrs will appear, and the width of the narrow hole shall be better than or equal to 1.5 times of the meat thickness. In addition, don't forget to mark the R angle when drawing. Male and female molds with right angles and acute angles are easy to crack. Once the production line stops, the chip repair will be lost.

6. If 90 degree angle is not required at the corner of the metal plate edge, it must be regarded as the appropriate R angle, because the right angle of the metal plate edge is easy to cause sharp points and injury. In terms of female mold, the tip of right angle is easy to crack due to stress concentration, and the tip of male mold is easy to crack, so it needs to repair the mold and delay mass production. Even if the die does not crack, it will wear and form R angle with the passage of time, resulting in burrs and defective products.

7.(1). Discount advantage can be divided into unilateral discount and bilateral discount. If there are requirements for accuracy, it is best to use bilateral folding, so that the accuracy will be better, and the height of folding shall be better than 3mm (T: 1.0-1.2mm), otherwise the clamping size will be too small and the size will be unstable.

7.(2). When the edge is discounted, the parts or internal protrusions on the side wall shall not be too close to the bottom, preferably more than 10mm. Otherwise, there is no punch at the corner below the protrusion, and its R angle will be greater than that on the left and right sides, affecting the appearance. We can make a suitable indentation on the discount before bending to improve the appearance.

7.(3). When the edge is discounted, the hole on the side wall should not be close to the bottom, but should be kept more than 3mm, otherwise the hole will participate in this deformation due to bending. Before bending, we can punch holes on the folding line with the same length, width and thickness as the holes. What does this do? It can cut off the resistance without affecting the appearance of the opening.