Bending Sheet Metal Rules

Bends can be short or long depending on what the design requires.

Bending sheet metal rules.

Runs right at the limit of precision flat sheet metal in a job shop environment. For bent sheet metal variation in the raw material thickness increases the recommended precision to 0 010 in. As per sheet metal design thumb rules the depth of bend relief should be greater than or equal to the inside bend radius of the bend and the width of the bend relief should be the same as the sheet metal thickness or more. Relief height is generally kept greater than two times of sheet thickness plus bend radius.

Sheet metal bending should be as perpendicular as possible to the direction of the metal fiber. Bending is performed by a press brake machine that can be automatically or manually loaded. Bend relief is provided at the end of bending edge in sheet metal design to avoid any crack tearing in the corner. When the sheet metal bend is parallel to the direction of the fiber of the metal material cracks are likely to occur at the bend of the sheet metal and the bending strength is low and it is easy to break as shown in the following figure.

As a general recommendation 0 005 in. There is no particular rule for how much the material should be weakened but as a rule of. Extrude hole size position guidelines creating an extruded hole using a punching process requires extreme pressure force. In other words if you re bending 1 8 sheet use a tool with a 1 8 radius to form the inside of the bend.

Here s a good rule of thumb for most materials. Bending is a process whereby a force is applied to sheet metal which causes it to bend at an angle and form the desired shape. When slotting sheet metal at the bend axis the material s average density in the bend region is decreased. Wipe bending or edge bending is another way to bend sheet metal edges.

The springback reasons for sheet metal bending the so called bending is the deformation of tensile stress and compressive stress on the front and back of the same plate. Grain structure in the metal sheet is critical for avoiding cracks in sheet metal parts with lugs or tabs that are cut on. The inside bend radius should be equal to the thickness of the material that you re forming. The slack between the wipe die and the punch plays an important role in getting a good result.

Once the plate is bent to the target angle the material will bounce back to its original shape once the pressure is removed due to tensile stress and compressive stress. Bend relief and collars near pierced areas strengthen sheet metal parts.