How to choose the right bending machine equipment?

A bending machine is a kind of machine for bending metal sheets, which is very common in industrial production. With the gradual development and growth of modern industry, users’ demand for bending machines has gradually increased, but with the increase in demand, some bending machines of uneven quality have gradually appeared in the industry, and the quality of these machines also determines the future. Smoothness or setbacks in the production process.

So how to choose a good bending machine correctly? It is recommended to carefully consider which model to buy from the machine’s main purpose, the possible deflection of the known machine, and the bending radius of the parts. When choosing a bending machine, as a decision maker, you also need to have a detailed understanding of the machine’s performance, processing range, processing function, processing accuracy, etc. The selection process is very important, because once you choose improperly, your subsequent production costs will rise, and the bending machine cannot recover the expected cost.

To this end, the editor has compiled the following content to help you choose your favorite bending machine:

press bending machine

1. Workpiece – specification and model

The important thing to consider first is the parts you want to produce. For a full accounting, you must fully estimate the standard size, shape, and structure of the parts you want to produce. Tonnage to the smallest machine to achieve the purpose of practical and economical.

Carefully consider sheet metal sheet material and maximum processing thickness and length. If the main product material is low-carbon steel, its thickness is within 3mm, and the maximum length does not exceed 2500mm, then the free bending force should not exceed 80 tons. But if there is a lot of bottom bending during the operation, then maybe you should consider buying a bending machine with a capacity of about 150 tons.

If the plate to be bent in production is low-carbon steel, with a thickness of up to 6mm and free bending within a length of 2500mm, then it is necessary to consider purchasing a bending machine of more than 100 tons. If the bending needs to be corrected during bending, then a bending machine with a larger tonnage is required.

If most of the workpieces to be bent are 1250mm or shorter, then the tonnage of the bending machine will be almost halved, which can greatly reduce the purchase cost. Therefore, the length of the processed parts is very important to determine the specifications of the model.

2. Deflection—compensation function

The bending machine will deflect during bending, especially when bending long workpieces. The longer the workpiece, the greater the degree of deflection. Under the same load, the deflection of the worktable and slider of the 2500mm model is 4 times that of the 1250mm model.

This means that shorter machines require fewer shim adjustments to produce acceptable parts, which in turn reduces setup time. However, at present, most CNC hydraulic bending machines have added a hydraulic deflection compensation function in production design, which reduces the adjustment of the equipment by production operators and improves bending accuracy and production efficiency. The hydraulic deflection compensation function is controlled by the numerical control system. The hydraulic oil enters the compensation cylinder through the magnetic servo valve to push the worktable upwards. At the same time, the deflection compensation force increases with the increase of the bending force, thus playing the role of deflection compensation.

Hydraulic Press Brake7

3. Material – bending force

The material of the processed sheet is also a key factor. Compared with low-carbon steel, the load required by stainless steel usually needs to be increased by about 50%, while the majority of materials are soft aluminum, which needs to be reduced by about 50%.

The bending pressure parameters of relevant standards can be obtained from the manufacturer. The table shows the bending force required for each 1000mm length under different thicknesses and different plates.

4. Bending radius – tonnage specification

In the process of bending products, the bending corner radius of the workpiece is also a factor to be considered. When using free bending, the bending radius is 0.156 times the opening size of the V groove.

During the free bending process, the opening size of the V groove should be 8 times the thickness of the metal sheet. For example, when bending 1.5mm low carbon steel with a V-groove opening size of 12mm, the bending radius of the part is about R=1.9mm. If the bending radius is close to the thickness of the plate or smaller than the thickness of the plate, it must be formed with a bottom die. However, the pressure required for bottom bending is about 4 times greater than that for free bending.

5. precision – intelligent numerical control

Bending accuracy is a factor that needs to be carefully considered. This factor determines whether you choose a CNC bending machine or an ordinary bending machine.

The purchase of a bending machine must involve the fineness used in the rigid indicators of the mechanical system, because from a scientific point of view, errors are inevitable, and the errors can only be reduced as much as possible. It is acceptable for some workpieces and some simple parts to have errors in a small range, then there is no need to pursue high-precision bending machines; some workpieces must be high-precision, which requires bending machines The precision is very high, and it is recommended that you buy a CNC bending machine.

If the bending accuracy requires ±0.5° and cannot be changed at will, you must focus on the CNC bending machine.

The repeat accuracy of the CNC bending machine slider can generally be guaranteed at ±0.01mm, and the accurate angle of forming must adopt such a precision and good quality mold. The repeatability of the ordinary bending machine slider is ±0.5mm, and there will still be a deviation of ±2~3° under the condition of using a suitable mold. In addition, CNC bending machines are equipped with quick clamps and quick die change systems. When you need to bend many small parts, CNC bending machines are an undoubted choice.

6. Mold – wear and tear

The bending die will also directly affect the bending accuracy, so the wear of the die should be checked frequently by measuring the length from the front end of the upper die to the shoulder and the length from the lower die to the shoulder.

Purchase summary:

As an equipment user or manufacturer, when purchasing a bending machine, the main thing is to purchase an economical and practical bending machine. Of course, this is to consider many factors and proceed according to your actual situation. The above points are just a brief overview of some one-sided issues. The recommended way is to choose a professional bending machine manufacturer and let them provide you with several sets of plan options according to your actual situation so that the decision-making plan is more reasonable and effective.

Contact us for more information:

WhatsApp: +86 15610187583