Bending Sheet Metal Rules

The slack between the wipe die and the punch plays an important role in getting a good result.

Bending sheet metal rules.

Bend relief and collars near pierced areas strengthen sheet metal parts. As a result the wipe die also determines the bend s inner radius. Here s a good rule of thumb for most materials. Bends can be short or long depending on what the design requires.

As a general recommendation 0 005 in. It is important to make sure that the sheet is properly pushed onto the wipe die. When slotting sheet metal at the bend axis the material s average density in the bend region is decreased. 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. 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. Sheet metal bending should be as perpendicular as possible to the direction of the metal fiber. If you re bending 0 020 thick material use a 0 020 radius.

Bending is performed by a press brake machine that can be automatically or manually loaded. Grain structure in the metal sheet is critical for avoiding cracks in sheet metal parts with lugs or tabs that are cut on. For bent sheet metal variation in the raw material thickness increases the recommended precision to 0 010 in. 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.

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. Runs right at the limit of precision flat sheet metal in a job shop environment. There is no particular rule for how much the material should be weakened but as a rule of. The inside bend radius should be equal to the thickness of the material that you re forming.

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. Relief height is generally kept greater than two times of sheet thickness plus bend radius.