What Is a Sheet Metal Press Brake Machine? Working Principles, Bending Techniques & Buying Guide

1. What is press brake forming?

1.1 Definition of press brake forming

Press brake forming process refers to a metal manufacturing process that uses a sheet metal press brake to clamp metal raw materials between a punch and a die to bend them into various pre-set shapes.

1.2 The purpose of press brake forming in the manufacturing industry

The purpose of press brake forming is to enable metal sheets to create various features and shapes in the manufacturing industry, improve metal strength and stability, and thus improve production efficiency.

1.3 Industries that use press brake forming

Generally, the industries that use press brake forming include automobile manufacturing, electronics industry, aerospace industry, construction industry, and furniture manufacturing.

2. What is a sheet metal press brake ?

2.1 Definition of Sheet metal press brake

Sheet metal press brake machine is a machine used to make various types of metal sheets into different shapes;

2.2 Purpose of sheet metal press brake

Sheet metal press brake machine is a very useful multifunctional equipment in the manufacturing industry:

3. Working principle of sheet metal press brake

3.1 Working principle

Sheet metal press brake machine is operated by hydraulic control through mechanical advantage. Usually, the metal sheet is fixed on the workbench, and then the upper die is used to apply pressure. With the extrusion of the upper and lower dies, the metal sheet is bent into various shapes. Generally, the bending angle is controlled between 30-90 degrees.

3.2 Basic process flow of press brake forming

Press brake forming is a basic process in metal processing, which is usually divided into the following steps:

3.3 Main press brake forming technology

press brake forming is mainly divided into four types of bending technology: air bending, bottom bending, stamping bending and three-point bending. Each technology has its unique advantages and characteristics. Let us introduce the basic situation of the four technologies.

3.3.1 Air bending

Definition: Air bending uses the principle of lever, and the metal sheet will not be in full contact with the mold.

Advantages: The advantage of air bending is that it is highly adaptable. The same set of tools can be used for different bending work, and the required bending force is smaller and the bending speed is faster than other methods.

Disadvantages: The defect is that its bending accuracy is low and the bending angle is not very accurate.

3.3.2 Bottom Bending

Definition: Bottom bending is different from air bending in that it requires the metal sheet to be in full contact with the die.

Features: The characteristic of bottom bending is that when the metal sheet is released during operation, it will rebound naturally.

Advantages: The advantages of bottom bending are high precision and good bending repeatability, which is more suitable for mass production;

Disadvantages: The only drawback is that its bending angle is limited and can only be used for bending at 88 and 90 degrees.

3.3.3 Stamping Bending

Definition: Stamping bending is a high-pressure bending technology that was originally developed for coin casting.

Features: Stamping bending is characterized by the need for heavy brakes and tools because it requires 4-5 times the force of air bending.

Advantages: Due to the huge pressure applied, its advantage is that it can bend metal sheets with large thickness tolerances;

Disadvantages: The disadvantage is that the aesthetics needs to be improved, and the shape of the metal sheet after bending is not good-looking.

3.3.4 Three-point Bending

Three-point bending is currently a relatively new technology with good flexibility and precision, but its initial cost is high and the market is limited.

Related technical reading : The Complete Guide to Press Brake Techniques:11 Types of sheet metal pressing process Explained

4. Mainstream types of sheet metal press brakes in the market

Sheet metal press brake machines currently mainly include servo hybrid press brakes, electro-hydraulic press brakes, pure electric press brakes, large-scale tandem press brakes and automatic robot press brakes.

4.1 Servo hybrid press brakes

The biggest feature of servo hybrid press brakes is energy saving and environmental protection. It perfectly combines hydraulic power and servo drive to improve efficiency while maximizing energy conservation.

4.2 Electro-hydraulic press brakes

Electro-hydraulic press brakes are the best-selling models in the market in recent years. One difference between them and traditional hydraulic press brakes is that they make reasonable use of electric motors to drive hydraulic pumps, reduce energy consumption, enhance motion and positioning control, and improve efficiency.

4.3 Pure electric press brakes

Pure electric press brakes are models that rely entirely on electricity to work. They have low maintenance costs and relatively low noise. They are very popular models.

4.4 Large-scale tandem press brakes

Large-scale tandem press brakes are more suitable for large-scale production. Multiple machines can operate in series and independently, which is very friendly to the industry of large-scale parts manufacturing.

4.5 Automatic Robot Press Brake

With the improvement of production technology, automatic robot press brakes are gradually adapting to the market. Automated production can not only make bending work more accurate, but also reduce labor costs and greatly improve work efficiency.

There are many types of sheet metal press brakes. When purchasing, we must make reasonable comparisons, purchase on demand, and choose the appropriate model according to actual requirements.

5. Composition and structure of sheet metal press brake

Sheet metal press brake is mainly composed of frame and structure, slider, workbench, back gauge system and mold type.

5.1 Frame

The frame is a solid structure that prevents deformation during bending operation and is the main frame of the machine.

5.2 Slider

The slider is driven by a hydraulic or electric system and applies force to the metal plate by moving up and down.

5.3 Workbench

The workbench is used to place the metal plate to be bent. It is a fixed part of the press brake to ensure that the material can be accurately aligned.

5.4 Back gauge system

The back gauge system is divided into three types: manual, automatic and CNC. It can be adjusted manually or automatically, which can ensure the accuracy of the bending process.

5.5 tool

There are different types of tools such as upper and lower molds, V-shaped molds, etc., which are tools to help metal plates to be formed during the bending process.

Related technical reading recommendations 1 : Press brake tooling Complete Guide: Pictures and text both profuse, understood at one look!

Related technical reading recommendations 2 : Master the Machine: Full Press Brake Structural Components Guide

6. How to choose a suitable sheet metal press brake

6.1 Main considerations

The main considerations for selecting a sheet metal press brake are divided into four aspects, namely the type and thickness of the processing material, the bending length and tonnage, the production batch and automation requirements, and the budget and plant space.

6.1.1 Type and thickness of processing materials: Different types of materials have different properties and thicknesses, which will affect the performance of the press brake.

6.1.2 Bending length and tonnage: The bending length and tonnage will directly affect the size of the processable parts. We must choose according to actual needs.

6.1.3 Production batch and automation requirements: The use of automated manufacturing can reduce labor costs and is suitable for large-scale batch production.

6.1.4 Budget and plant space: When choosing a sheet metal press brake machine, we must fully consider the initial investment cost and the required space and purchase it reasonably.Galvanized steel: There is a layer of zinc coating on the surface of galvanized steel, which has strong corrosion resistance and can be used to make the hull.

6.2 Selection suggestions

When choosing a sheet metal press brake machine, we must choose the correct and appropriate model according to our actual needs and different requirements, purchase on demand, and use it reasonably. Choosing the right model can greatly improve production efficiency.

7. Common problems（FAQS)

8. Conclusion

With the continuous advancement of modern technology, sheet metal press brakes have gradually become indispensable working equipment in the manufacturing industry, playing a vital role in all walks of life. Its advantages of high efficiency, flexibility and versatility have greatly improved the efficiency of bending work.