How to improve and increase the efficiency of the bending process (Part 1)

What are the types of Press BrakeToolings? How to choose the Press Brake Tooling type?

Among them, V-bending includes the following three types: point-contact bending, bottoming bending and stamping bending.

Since V-bending is widely used in actual processing, today we will mainly talk about what we must know in V-bending.

How to choose the V width of the lower die?

How to calculate the pressure required for Press Brake?

After obtaining the processing drawings, the pressure required for bending should be calculated according to the information on the drawings. It is time-consuming to calculate one by one every time.

Based on the processing data collected by tens of thousands of customers worldwide for decades, the following bending pressure gauges are summarized. You only need to compare the following table and find out the corresponding bending pressure according to the material thickness and V width on the drawing, which is very convenient at a glance.

After selecting the "plate thickness" (t) of the material in the pressure gauge and the "inside radius" (ir) of the bend, the following information can be found:

①The pressure (ton / m) required for bending 1m of this material.

②Use the V width (mm) of the mold when bending.

③The minimum bending edge length (mm).

How to choose the lower die?

Three principles for choosing the lower die:

①During stamping and bending → A lower die with a lower die V-groove angle of 90 ° is required.

②When touch bending or bottom bending → Select the lower die whose V-groove angle of the lower die is ≤88 °.

③In order to reduce the scratches of the workpiece → choose a lower die with a larger shoulder R and V width.

5. How to choose the upper mold?

①When stamping and bending → It is appropriate to select the upper die with the tip angle of the upper die 90 ° and the tip R 0.2-0.6 mm.

②For point-touch bending and bottom-touch bending → It is appropriate to select the upper die with a tip angle of ≤88 °. At the same time, the V-groove angle of the lower mold should be greater than or equal to the upper mold angle.

6. How to decide the bending sequence?

   When selecting the bending sequence, the complex shape can be divided into simple shapes, which makes it easier to select.

Five basic principles that determine the bending sequence:

① Start bending from the bending line on the outside of the workpiece.

② Bend in order from short to long.

③Bending starts from the middle stand (bending in the middle).

④ Can be folded together with the same knife (mold type).

⑤Bends with high bending edges are placed at the end.

How to calculate elongation?

When using direct input or angle input in the programming mode of the bending control system NC, it is necessary to perform unfolding calculation according to the bending sequence, and enter the L value, bending edge size and other data in the NC.

How to judge whether it can be processed?

Different bending types have different criteria for judging whether bending is possible. Today we mainly take V-bending as an example to judge whether it is possible to bend.

Influencing factor 1: V width

Can the machine capacity meet the pressure corresponding to the V width used?

V width: the distance connecting two points on the upper surface of the lower mold slope.

V width = 6 ~ 8t (bottom bending)

Internal R≤1 / 6V (Internal R≤1t ~ 2t)

The bending pressure required per meter of SPC material is expressed by P:

P = 68 × t × t ÷ V

Therefore, we need to pay attention to the following two points：

1. The processing capacity of the Press Brake used must be greater than or equal to the pressure corresponding to the selected V width.

2. The bending length is too long, which may exceed the processing capacity of the Press Brake.

Influencing factor 2: minimum bending edge

Is the height of the bending edge higher than the minimum bending edge of V width?

The minimum bending edge: generally refers to the height of the minimum bending edge that can be bent relative to the V width used when bending at 90 °.

The minimum bending edge height b represents:

b = V / 1.4

Therefore, we need to pay attention to the following two points.

1. The bending edge height must be greater than the minimum bending edge height corresponding to the V width.

2. If the bending edge height is less than the minimum bending edge height corresponding to the V width, you need to select a smaller V width for processing, which may cause the required pressure to increase and the number of mold changes to increase.

So how to edit the bending data more easily, faster and more accurately, and produce higher quality products more quickly?