Press Brake 101: Everything You Need to Know (2023 Updated)

To help you fully comprehend the press brake machine, we conducted extensive research and have composed this comprehensive article. It covers all aspects of the press brake machine, including but not limited to its definition, history, types, working principle, advantages and disadvantages, parts, functions, parameters, applications, tooling, operation, repair, maintenance, and more.

We’ve also included various supplementary materials, such as operating instructions, purchasing guides, and lists of top press brake manufacturers.

By reading this article, you will gain a systematic and in-depth understanding of the press brake machine and be better equipped to operate it effectively.

Let’s get started.

What is a press brake machine?

Some people often ask: What is a press brake? What is a press brake machine? Is a brake press and a press brake the same thing? What is a press brake used for?

The answers to all of these questions are the same. Simply put, a press brake is a piece of equipment used to bend and form sheet metal. If you would like to know the definition of a press brake in more detail, including its history and why it’s called that, please read the article linked below.

• What Is a Press Brake (And Why Is It Called That Way)?
• Parts And Functions Of Press Brake You Should Know

This video may help you understand the process of bending sheet metal parts using a press brake.

Further reading:

• Things You Should Know About Press Brake
• Press Brake Bending Basics (A Guide to Sheet Metal Bending)
• 45 Press Brake Terminology You Should Know

Different types of press brake machine

How many types of press brakes are there?

There are several types of press brakes, but the most commonly used are down-moving hydraulic press brakes and CNC press brakes, depending on the classification method used.

Let’s learn more about it through the following classification methods:

Classified by the source of bending force

According to the source of bending force, the press brake is divided into:

• Mechanical press brake
• Pneumatic press brake
• Hydraulic press brake
• Servo-electric press brake

Mechanical press brake

For the mechanical press brake, the vertical movement of the ram is driven by a crank mechanism which is powered by the flywheel.

Pneumatic press brake

And the pneumatic press brake makes use of air pressure to move the ram.

Hydraulic press brake

The hydraulic press brake utilizes the two synchronized hydraulic cylinders to move the ram.

Servo-electric press brake

The servo-electric press brake uses a servo-motor to drive a ball screw or belt drive to apply force on the ram, causing it to move vertically. Prior to the 1950s, mechanical brakes were the dominant choice in the global market.

However, with advancements in hydraulic technology and computer controls, hydraulic press brakes have become the most widely used option worldwide.

Classified by operation

From another point of view, the press brake can be divided into:

• Manual press brake
• Hydraulic press brake
• CNC press brake

Manual press brake

It is the most common type among various press brakes, also known as a sheet metal brake. Manual press brakes require manual adjustments of the bending dimensions and angles during use.

It consists of a worktable, supporters, and a clamping plate. The worktable is mounted on supporters, which consist of a base and pressure plate.

Manual press brakes are more complex to operate than other types of press brakes, so it is necessary to confirm the bending size and angles before starting mass production.

After completing one batch of mass production, adjustments to the bending size and angles must be made for continued production.

Hydraulic press brake

Classified by synchronization, the hydraulic press brake can be divided into:

• Torsion Synchro Press Brake
• Electro-Hydraulic Synchro Press Brake
• Hybrid Press Brake

Classified by movement, the hydraulic press brake can be divided into:

• Up Moving Press Brake
• Down Moving Press Brake

CNC Press Brake

An electro-hydraulic servo press brake is a type of sheet metal processing equipment that offers high precision and efficiency. The following components are included in its design:

• Machine frame
• Ram (slider)
• Workbench
• Oil cylinder
• Hydraulic proportional servo system
• Position detection system
• CNC controller
• Electrical control system

Further reading:

• What are The Advantages of Electric Servo Press Brake Over Hydraulic Press Brake？

The CNC press brake is a highly efficient and precise sheet metal processing equipment that performs bending by controlling the ram stroke and back gauge.

The operator only needs to input the number of pieces to be bent and the bending angle for each step, and the CNC press brake will perform the bending process according to these specifications.

Advanced CNC press brakes adopt hydro-electric servo systems and grating rulers to form a closed-loop control system, ensuring high control accuracy, bending accuracy, and repositioning accuracy.

With advancements in technology, electro-hydraulic servo synchronization technology is being adopted to upgrade the system, providing numerous advantages.

• CNC Press Brakes use an electro-hydraulic servo system to control the two-cylinder synchronization, with the international standard grating ruler to realize full closed-loop control. It features high precision synchronization, high bending accuracy, and high repeat positioning accuracy.
• The press brake is equipped with a hydraulic automatic clamp or fast clamp for the upper die and a socket lower die, based on the customer’s requirement, to reduce labor intensity and improve production efficiency.
• The back gauge can be extended to 6 axes, and the crowning is automatically adjusted by the controller, providing convenience and accuracy.
• The press brake is equipped with components such as the Germany Bosch-Rexroth valve block, linear motion guide, and ball screw manufactured by BLIS, Taiwan HIWIN, or other international companies to ensure positioning accuracy.
• The upper die, which comes in different lengths, can be assembled into a certain width to meet the special requirements of the workpiece.
• An automatic cylinder crowning system overcomes the impact on workpiece quality caused by ram deformation and ensures the straightness and bending angle of the final products.

Further reading:

• 6 Types of Press Brake Bending
• Tips For Using CNC Press Brake
• Application And Development Of CNC Press Brake
• What Is Press Brake Crowning And 3 Types of It

Working principle of press brake machine

How does a hydraulic press brake work?

In simple terms, the press brake works by using the relative motion of the punch and die, which are fixed on the upper and lower worktable, to achieve bending of sheet metal materials through hydraulic transmission.

A more detailed explanation:

The hydraulic press brake machine incorporates numerical control technology, servo, and hydraulic technology. The left and right cylinders are driven to extend and retract by controlling the action of the valve. This movement drives the ram of the press brake machine to rise and fall.

The synchronous action of the ram is achieved through the combination of grating signal feedback and proportional valve flow, which is controlled by the CNC system. The numerical control system also features a display screen for human-machine interaction and simulation of the bending process.

The CNC system controls the opening of the two valves for the left and right cylinders. If necessary, the flow in the cylinder can be redirected by the servo valve, causing the upper beam to move linearly in a vertical direction. The amount of movement is determined by the newly measured pulse count.

The signal from the CNC controller is converted into a hydraulic signal to control the action of the valve through the servo valve. Each cylinder in the hydraulic system has its own independent control circuit, servo valve, and filling valve.

The bending of the workpiece at different angles can be achieved in one operation.

Hydraulic Press Brake Working Principle Diagram

Further reading:

• How Does the Press Brake Hydraulic System Work?
• Things You Should Know About Press Brake
• Press Brake vs. CNC Folder (The Ultimate Difference Analysis)
• What is CNC press brake and it’s working principle

Advantages and disadvantages of press brake

Advantages of press brake

(1) Suitable for small batch and multi-variety production:

The press brake allows for versatility with a single set of punch and die, making it suitable for producing a wide range of materials and parts.

(2) Low cost and long lifespan of bending dies:

Each set of bending die costs only a few thousand yuan, and the manufacturing process is straightforward, eliminating the need for repeated trials. Moreover, each set of die can last for at least 10 years, reducing the overall cost of die manufacturing.

(3) Capable of producing “S” and “U” shaped parts:

In stamping molding, producing “U” shaped parts is particularly challenging. Press molding requires a certain amount of rebound, which can lead to difficulties in fitting the punch and die together. The press brake, on the other hand, solves this issue by performing multiple bending operations.

(4) Ideal for trial production of new products:

The versatility of a press brake allows for the production of parts with different shapes, sizes, and angles using a single set of punch and die. This makes it ideal for trial production of new products without incurring additional costs.

(5) Capable of forming a variety of polyggon shapes with different heights:

The press brake machine can produce multi-bend parts with different edge heights by adjusting the material and angle settings.

(6) Deflection compensation function:

When bending long workpieces, there can be a significant deviation between the forming angle of the middle and the sides, leading to uneven angles. The press brake, however, has a deflection compensation function that allows for adjusting the angle at each position, ensuring straight bending and reducing the need for manual adjustment and repair. This streamlines the production of long parts, reduces labor intensity, and improves product quality.

Disadvantages of press brake

(1) Requirements for Material Thickness

Materials used in bending must meet certain thickness requirements. As a rule of thumb, materials with a thickness of no more than 50mm can be easily bent, but those with a thickness greater than 50mm require substantial bending force. Commonly used press brakes in enterprises have capacities of 400t, 300t, 160t, and 80t.

(2) Risk of Fracture during Bending

During the bending process, edges and corners of the material can develop burrs or oxide layers, which can lead to cracking or fracture of the material during bending. This makes it challenging to ensure the quality of the final product.

(3) Indentation during Bending

Indentation is a frequent quality issue that occurs during bending. In some cases, the chosen bending die may not be suitable or an appropriate die set must be used, resulting in unavoidable indentation. In such cases, an additional grinding process is necessary, and the thickness of the polished material and parts must be tested. Deep indentations can result in scrapping of materials and parts, increasing the cost.

(4) Slippage during Bending

During bending, some materials may slip, causing the bending part to turn out. Square materials typically do not encounter this issue, but irregular materials may slip easily, resulting in non-compliance with process standards.

Further reading:

• Everything You Should Know About Sheet Metal Bending

Specifications of press brake

The specifications of the press brake machine encompass various aspects including nominal pressure, workbench length, workbench height, ram stroke, maximum opening height, ram stroke adjustment, column spacing, throat depth, ram speed, main motor power, oil pump, maximum system pressure, overall dimensions, among others.

It is important to note that the parameters of press brake machines produced by different manufacturers can vary.

Therefore, when making a purchase, it is crucial to carefully compare these parameters to ensure that the technical specifications of the machine meet your needs and requirements.

Further reading:

• How To Improve The Accuracy Of Heavy-duty Press Brake

Application of press brake

Press brakes are widely used in energy, transportation, automobile, machinery, metallurgy, shipbuilding, aviation, military, agricultural machinery, petroleum machinery, power generation industries.

Further reading:

• Press Brake Bending Basics (A Guide to Sheet Metal Bending)
• 4 Difficulties in Press Brake Bending

Toolings of press brake

What is press brake tooling?

Press brake tooling is an essential component of press brake machines that helps to ensure the accuracy and quality of the final bent parts. It is composed of a punch and a die that are used to shape and bend metal sheets or plates into the desired shape.

The tooling is made of high-strength materials, such as hardened steel, to withstand the high pressure and forces during press brake operations.

There is a wide range of shapes and sizes available to cater to different applications and workpieces.

The die used for forming has a cavity, while the die used for separation has a blade edge.

Further reading:

• Press Brake Tooling Chart
• Press Brake Dies (Toolings): The Ultimate Guide
• Press Brake Dies Practical Use (and It’s Scope)

Manufacturer of press brake

You may be wondering who makes the best press brake. The following press brake manufacturer ranking list will certainly assist you in choosing the ideal press brake manufacturer. We may include our press brake reviews below the list in the near future.

• Top 20 Press Brake Manufacturers
• How Does the manufacturing Accuracy of The Press brake Affect The Bending Accuracy？

Maintenance checklist of press brake

Before performing maintenance or cleaning on the press brake machine, align the top punch with the bottom die, then turn off the press brake until the work is completed.

If it is necessary to start the machine or carry out other operations, make sure to select the jog mode for safety.

Here is a press brake maintenance checklist:

Hydraulic oil circuit

• Weekly inspection of the oil levels in the oil tanks should be conducted as part of the hydraulic system maintenance. If the oil level is below the oil window, the oil tank should be filled with hydraulic oil.
• The hydraulic oil used in the press brake should be either ISO HM46 or Mobil DTE25.
• The oil in a new press brake should be changed after 2000 hours of operation, and thereafter should be changed every 4,000 to 6,000 hours. The fuel tank should be cleaned with every oil change.
• The oil temperature in the system should be between 35℃ and 60℃, and should not exceed 70℃, as higher temperatures can lead to deterioration of the oil and cause damage to accessories.

Filter

• During each oil change, the filter should be either replaced or thoroughly cleaned.
• If the press brake experiences related alarms or the oil appears unclean, or there are other unusual conditions for the filter, it should be replaced.
• The air filter on the tank should be cleaned every three months, with replacement being preferable every year.

Hydraulic parts

• Monthly cleaning of hydraulic components, such as substrates, valves, motors, pumps, and tubing, should be performed to prevent dirt from entering the system. No detergents should be used.
• After one month of use, check the bending point of the tubing for any deformations and replace it if necessary. After two months of use, tighten all connection parts while the press brake is shut down to ensure there is no pressure in the system during the work.

As a press brake operator, it is important to read through the following analysis of common press brake failures in order to possibly prevent and resolve significant issues.

Further reading:

• Repair and maintenance of CNC press brake
• Troubleshooting 56 Press Brake Bending Problems

Inspection checklist of press brake machine

Brief Description

• Standard test order does not mean the actual test order, it is changeable
• Adjusting the mechanism and parts that may affect the precision is prohibited during the test process.
• Workpiece precision inspection conditions:
• Requirements on workpiece
• If the workpiece is made by an A3 steel plate, it’s tensile strength Qb≤ 450MPa
• The number of workpieces shall not less than 3 pieces
• The opening size of the lower die shall be 8-10 times as large as the workpiece thickness
• The workpiece should be put on the worktable middle position
• The bending angle is 90°
• Measure from end 100mm

The inspection method and accuracy range shall be based on GBT-14349-2011-Metal Press Brake- Precision

Note: the worktable is floated, inspection G2, G3 shall refer worktable vertical plate as a benchmark.

Tonnage calculation of press brake

You may be wondering about the size of press brake you need. How do you calculate the press brake forming force? What’s the formula for calculating press brake tonnage? The easiest way to determine the required press brake capacity for your bending work is to refer to the chart below.

Press brake bending chart (metric)

The bending force referred to in the above quick reference chart is based on the following conditions:

The required bending force per meter (T/m) when the lower die opening and plate thickness are confirmed, and the material’s tensile strength is 45kg/mm² (450N/mm²).

When the material has a different tensile strength of σ (kg/mm²), the required bending force per meter (T/m) can be calculated using the following formula.

F1 = F0·σ/450 (T/m);

See also:

• How to Calculate Press brake Tonnage (By Chart, Formula & Calculator)
• Press Brake Tonnage Calculator
• How To Calculate Bending Force in Air Bending (Sheet Metal)?
• Air Bending Force Chart: The Most Authoritative Data From Amada

Press brake controller manual

There are two popular press brake controllers, namely the one from China’s Estun, which is the exclusive agent of DELEM control in China, and the other one is DELEM from the Netherlands.

See also:

• How to Choose Press Brake Controller, NC or CNC?
• Press Brake Controller: E21 V.S E200P
• 4 Ways for Press Brakes Controller Return to the Reference Point

The key factors for a press brake machine are divided into two parts: the machine itself, such as its quality and accuracy, and the control system. You can download the installation and operation manual for press brake controllers in PDF form from the following link.

Operation Manual:

• Press Brake Estun E21 Operation Manual
• Press Brake Estun E200P Operation Manual
• Press Brake Estun E300 Operation Manual
• Press Brake Delem DA41 Operation Manual
• Press Brake Delem DA52s Operation Manual
• Press Brake Delem DA-66T Operation Manual

Installation Manual:

• Press Brake Estun E21 Installation Manual
• Press Brake Estun E200P Installation Manual
• Press Brake Estun E300 Installation Manual

Programming and setup of press brake machine

The above operation manual and installation manual of press brake controllers provide clear explanations of programming and setup. Please download them from the provided link and read them carefully.

Instructions on How to Use a Press Brake:

As an example, here is a simple introduction on how to use a hydraulic press brake to fabricate Q235 mild steel:

First, connect the power, turn on the key switch on the control panel, and then press the pump to start. You should be able to hear the sound of the oil pump rotating. (The machine will not start running at this time)

Pay attention to stroke adjustment for the press brake operation. This must be tested before bending. Ensure that there is clearance equal to the thickness of the plate when the top punch is down at the bottom of the lower die, otherwise the mold and press brake may be damaged. The stroke adjustment can be performed through electric quick adjustment or manual fine adjustment.

For V-width selection, the width of the V opening should typically be 8 times the thickness of the plate. For example, when bending a 4mm plate, you should choose a 32mm V-opening die.

The back gauge adjustment usually has both electric fast adjustment and manual fine-adjustment.

Step down the pedal switch to start bending. You can stop the machine at any time by releasing the foot. If you release your foot, the bending machine will stop and you can continue bending by stepping down the switch again.

Here, we provide press brake operation manuals to guide you in operating the press brake.

• Press brake operating manual
• Electro-Hydraulic Servo Press Brake Operation Manual
• 22 Tips For Using New Press Brake
• Tips for Using CNC Press Brake

Furthermore, by reading the articles in our bending category, you can gain knowledge about various aspects of press brake and sheet metal bending. It is recommended to take your time to carefully read and learn from these articles.

Training of press brake

Training for press brake usage and programming can also be acquired by referring to the manuals. These manuals can be easily downloaded from the link provided above and can be studied at your convenience, wherever you are and at any time.

Further reading:

• 6 Essential Knowledge For Press brake Operator’s Safety Training

DIY press brake

Sometimes, workshop owners only need to bend a few pieces of steel, making it not cost-effective to purchase a brand new press brake. As a result, they may opt to build their own press brake for simple bending purposes, creating a homemade metal brake press.

Here, I have collected some videos on building a home-made press brake. I hope that these tutorials will help you make one on your own.

What is the price of a press brake machine?

How much does a press brake cost? Or what is the price of a press brake?

The cost of a press brake machine is largely determined by its bending force, length, and control system. Other factors that influence the price include the brand, type, specifications, and market.

To provide a general idea of the price range for press brake machines, we have created a reference table for both NC and CNC press brakes.

Press Brake Price Table (USD)

How to choose a press brake machine?

If you’re in search of the perfect hydraulic press brake machine for your needs, then you should definitely read this comprehensive guide on selecting the right machine.

This article offers a complete overview of the press brake world, starting with a definition of a press brake, followed by an explanation of the different parts of a hydraulic press brake. It covers different types of press brakes, including manual, hydraulic, and NC/CNC types, and provides a comparison of the pros and cons of NC press brakes versus CNC press brakes.

This guide also highlights key factors to consider when selecting a press brake and provides useful tips on how to choose the right machine. In short, it is a must-read for anyone who’s looking to purchase a press brake machine.

Related reading: Press Brake Buying Guide