- Sheet metal on both sides of the corner after bending, due to extrusion, there will be metal material protruding.
As a result, the width is larger than the original size, and its protruding size is related to the thickness of the material used. The thicker the material, the larger the protruding point.
In order to avoid this phenomenon, you can make a semicircle on both sides of the bend line beforehand. The diameter of the semicircle is preferably 1.5 times the thickness of the material.
The same way is used when the leftover material is folded back.
- When the sheet metal is bent by press brake machine, the internal R angle is preferably greater than or equal to 1/2 of the material thickness.
If you do not make the R angle, the right angle will gradually disappear after multiple punching and the R angle will naturally form. After that, the length of one or both sides of the R angle will become slightly longer.
- Sheet metal is easily deformed when it is bent.
In order to avoid deformation, an appropriate amount of 45-degree reinforcement ribs can be added to the bends to increase the strength on the principle of not interfering with other parts.
- Generally, it is difficult to maintain the straightness of a sheet metal part when it is narrow and elongated, and it is easier to deform after being stressed.
Therefore, we fold one side into an L-shape or fold two sides into a 冂-shape to maintain its strength and straightness, but often the L and 冂-shape cannot be connected from beginning to end. What should you do if it is interrupted due to some factors?
A proper amount of ribs can be added to increase its strength.
- It is best to have narrow holes in the turn between the flat surface and the bending surface, or the edge of the opening should be retracted after the bending, otherwise burrs will occur.
The width of the slit is preferably greater than 1.5 times the thickness of the sheet.
Also don’t forget or be lazy when making drawings without marking the R corner.
Right-angle or acute-angle male and female molds are prone to cracking. In the future, the suspension and repairs will be additional losses.
- At the corner of the edge of the metal sheet, if there is no special requirement for a 90-degree angle, please be processed to an appropriate R angle.
The right angle on the edge of the metal sheet can easily cause sharp points and cut staff.
The right-angled tip of the die is prone to cracking due to stress concentration.
The top punch is easy to crack at the tip, so the mold must be repaired and mass production is delayed.
Even if it does not crack, over time, the R angle will be caused by wear, which will cause burrs on the product and cause defective products.
It can be divided into unilateral bending and bilateral bending. If precision is required, it is best to use bilateral bending. The precision is better.
The height of the folded edge is preferably greater than 3mm. (T: 1.0 ~ 1.2mm), otherwise the dimensions will be unstable due to too few clamping dimensions.
7.1 When folding edges, the parts on the side walls or the internal protrusions must not be too close to the bottom surface, preferably more than 10mm, otherwise the bending radius of the corners below the protrusions will be larger than the radius of the left and right sides due to the absence of a punch. If the R angle is not continuous, it will affect the appearance.
An appropriate length of indentation can be punched on the fold line before bending, which will improve its appearance.
7.2 When folding edges, the openings on the side walls should not be too close to the bottom surface, preferably 3mm or more, otherwise the openings will be deformed due to bending.
Before bending, a long hole with a length equal to 1.5 times the thickness of the opening is punched on the folding line. Its function is to be able to cut off the drag without affecting the appearance of the opening.
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