**The relationship between sheet metal bending radius and thickness**

The experience in actual sheet metal processing shows. When the general plate thickness less than 6mm, the inner radius of the sheet metal bend can be directly used as the radius when bending.

**The details situations as following:**

When the plate thickness more than 6mm and less than 12mm, the bending radius in the plate is generally 1.25 to 1.5 times the plate thickness. And when the plate thickness is more than 12mm, the bending radius in the plate is generally 2 to 3 times the plate thickness.

When the bending radius is R = 0.5, the general sheet metal thickness T is equal to 0.5mm. If you need a radius larger or smaller than the plate thickness, you need to use customized mold.

When the sheet metal drawing requires the sheet to be bent 90 °, and the bending radius is particularly small. The sheet should be processed with a planing grooving before the sheet metal is bent. It can also process the upper and lower dies of customized press brake molds.

Figure-1

The bending radius of the sheet metal has a certain relationship with the width of the groove in the lower die.

After a lot of experiments in sheet metal processing, it is found that there is a certain relationship between the groove width under the bending die and the bending radius. For example: 1.0mm thickness sheet is bent with 8mm slot width, so the bending radius pressed out is ideally R1.

Figure-2

If use 20mm slot width for bending, since the upper mold moves downwards during bending, the depth of the stretched sheet reaches a certain angle. Then we know that the groove area of 20 mm width is larger than the groove area of 8 mm width. When bending with 20 mm width groove, the stretched area will increases, at the same time R angle also increases.

Therefore, when there is a requirement for the bending radius of the plate without damaging the press brake mold. We try to bend with a narrow groove as much as possible. Under normal circumstances, it is recommended to operate according to the standard plate thickness and slot width ratio of 1: 8. The minimum must not be less than the ratio of the plate thickness to the slot width of 1: 6 to operate. The sheet metal bending can be appropriately smaller, not less than the ratio of the plate thickness to the slot width of 1: 4 to operate.

**Suggestion:**

When strength permits, it is preferred to use the planing method before bending. It can make a small sheet metal bending radius.

The bending radius of sheet metal processing is related to the material thickness and bending notching width. The simple and convenient method is as follows:

Generally, when the plate thickness less 6mm. The bending radius in the plate can be directly taken as the radius of the plate thickness during bending. When the plate thickness is more than 6mm and less than 12mm. The bending radius in the plate is generally 1.25 to 1.5 times the plate thickness. When the thickness is not less than 12mm. The bending radius in the plate is generally 2 to 3 times the plate thickness.

The following figure is the corresponding table of bending radius, pressure and minimum bending height

Figure-3

**Code explanation: V=bending notch width, R=bending radius, B=minimum bending height, S=sheet thickness**

Figure-4

Note: The data with gray scale in the table is the pressure P (kN / m) required for bending. The maximum pressure of the bending machine is 1700kN. And the existing bending blade V = 1, 16, 25, 40, 50 five specifications. We need to know the bending radius with exsiting knife edge and benging length. So that we can accurate unfolded material length.

The above description is the pressure parameters and bending notch width of press brake. The actual application is calculated and used according to the bending pressure. Bending notch of the sheet metal processing factory.[/fusion_text][/fusion_builder_column][/fusion_builder_row][/fusion_builder_container]