The Main Differences Between Twisting Axis Bending Machine and Electro-Hydraulic Bending Machine
There are various types of bending machines available in the market, each with different configurations and corresponding systems. Among them, the twisting axis bending machine and the electro-hydraulic bending machine are often compared due to their similar functions but different components, systems, and prices. So, how can we choose a high-performance, cost-effective, and user-friendly bending machine that will never fall behind from the many options available? In the following discussion, we will explore the differences between the twisting axis bending machine and the electro-hydraulic bending machine from multiple perspectives.
Different Structural Principles
The two machine types have different design principles, which result in different structures for ensuring synchronous movement of the bending slider on both sides. The twisting axis bending machine uses a twisting axis to connect the left and right swing arms, forming a twisting axis that forces the synchronous movement of the cylinders on both sides. Therefore, the twisting axis bending machine employs a mechanical forced synchronization mechanism, and the parallelism of the slider cannot be automatically checked and adjusted. On the other hand, the electro-hydraulic bending machine installs a grating ruler on the slider or the bed, and the CNC system can analyze the synchronous condition of both sides of the slider through the feedback information from the grating ruler. If any deviation occurs, the CNC system will make adjustments through proportional electro-hydraulic servo valves to ensure the synchronous movement of the slider. The CNC system, hydraulic control valve group, and grating ruler together form a closed-loop feedback control system for the electro-hydraulic bending machine.
Workpiece Precision
The parallelism of the slider determines the angle of the workpiece. In the twisting axis bending machine, the slider synchronization is mechanically maintained without real-time error feedback, and the machine itself cannot make automatic adjustments, resulting in poor machining precision. Additionally, its off-load capacity is also inferior because the twisting axis bending machine relies on the twisting axis to force the synchronous movement of the cylinders on both sides. Prolonged off-load operation can cause deformation of the twisting axis. On the other hand, the electro-hydraulic bending machine achieves synchronous control of the slider through a proportional electro-hydraulic valve group and real-time error feedback from the grating ruler. If any deviation occurs, the system adjusts the slider through the proportional valve to maintain synchronization, thereby improving machining precision.
Bending Process
Operating Speed
Three factors determine the operating speed of the machine: (1) the speed of the slider, (2) the speed of the back gauge, and (3) the bending steps. The twisting axis bending machine uses cylinders with a ratio of 6:1 or 8:1, resulting in slower speeds. In contrast, the electro-hydraulic synchronous bending machine uses cylinders with a ratio of 13:1 or 15:1, enabling faster speeds. Therefore, the downward speed and return speed of the slider in the electro-hydraulic bending machine are much higher than those of the twisting axis bending machine. While the twisting axis bending machine has functions for both fast and slow downward movement of the slider, the fast downward and return speeds are only 80mm/s, and the transition between fast and slow movements is not smooth. The speed of the back gauge is only 100mm/s. In comparison, the electro-hydraulic bending machine has functions for both fast and slow downward movement of the slider, with fast and return speeds reaching 200mm/s, and the transition between fast and slow movements is smooth, greatly improving production efficiency. At the same time, the speed of the back gauge can reach 400mm/s.
Comparison of Operating Speed
Mechanical Strength
Due to its design, the twisting axis bending machine cannot handle off-center bending. Prolonged off-center bending can cause deformation of the twisting axis. In contrast, the electro-hydraulic synchronized CNC bending machine does not have this issue. The Y1 and Y2 axes on both sides operate independently, allowing for off-center bending.
Twisting Axis in Twisting Axis Bending Machine
Actual Operation
Most twisting axis bending machines do not come with CNC systems or V-axis compensation. Therefore, when processing based on drawings, they rely on the experience of skilled workers to make trial bends. If the results are not satisfactory, further trials are needed, resulting in waste material and limited options for skilled workers, whose wages are usually higher. Of course, a manual compensation system can be added if necessary. On the other hand, the electro-hydraulic bending machine is controlled by a professional CNC system with V-axis compensation, making the operation simple and requiring less experience from the workers. It has a simulation bending function, eliminating the need for trial bending and only requiring the input of dimensional corrections based on the drawings for direct bending.
Manual Compensation System (top right) and Electric Axis Compensation (bottom left)
CNC Axes
The performance of the twisting axis bending machine deteriorates as the number of controlled axes increases. Usually, only the X and Y axes are controlled. The electro-hydraulic bending machine is not limited by the number of axes and can have a minimum of 3+1 axes, allowing for automated program design to meet high requirements, such as 4+1, 5+1, 6+1, 7+1, 8+1 axes, and so on. With the coordination of multiple axes, the workpiece can be clamped once on the bending machine, and automatic tool change, rotation of the spindle head, rotation of the worktable, and other operations can be performed to complete complex processes and multi-surface machining. This not only improves the surface finish but also greatly enhances efficiency.
Commonly Used Multi-Axis Options in Electro-Hydraulic Bending Machines
Advanced Options
The twisting axis bending machine can be equipped with some improved configurations, such as ordinary quick clamps, manual compensation, up and down stop fingers, ball screws and linear guide back gauges, oil coolers, and light curtains for protection. However, the electro-hydraulic bending machine can not only be equipped with these basic configurations but also offers a variety of advanced accessories. For example, it can be equipped with a higher-quality TYOKKO or AMADA quick clamps in addition to the standard quick clamps. The up and down stop fingers can be manually operated or equipped with an electric Z-axis stop finger that runs on a guide rail using an AC motor. The light curtain protection can be replaced with a more sensitive and secure laser protection. Other options include a servo pump control system that offers advantages such as energy efficiency, low noise, high stamping speed, higher accuracy, and lower oil consumption; a robotic arm that significantly improves production efficiency; hydraulic clamping systems; and dynamic material supports and laser angle detectors.
Twisting Axis Bending Machine (left) and Electro-Hydraulic Bending Machine (right) with Common Optional Configurations
The main differences between the electro-hydraulic bending machine and the twisting axis bending machine lie in whether they have closed-loop feedback and electro-hydraulic compensations. The twisting axis bending machine adjusts the cylinder stroke mechanically, while the electro-hydraulic bending machine controls the stroke hydraulically. The twisting axis bending machine relies on a balance shaft for control, while the electro-hydraulic bending machine achieves synchronization through servo proportional valves on both sides. The electro-hydraulic bending machine combines the advantages of electrical and hydraulic systems, offering high control precision, fast response speed, high output power, flexible signal processing, and easy implementation of various parameter feedback. The efficiency of an electro-hydraulic bending machine can be equivalent to two or three twisting axis bending machines.
In conclusion, when selecting a bending machine, it is important to consider the actual processing requirements. The electro-hydraulic servo synchronized bending machine offers high precision with real-time error feedback and has a stronger resistance to off-center loads. The twisting axis synchronized bending machine has lower precision without error feedback and has a weaker resistance to off-center loads. The electro-hydraulic bending machine is more complex and has a higher price. Based on the information provided above, you can choose a suitable bending machine based on the following specific aspects:
1. Precision requirements for the workpiece (deviation in twisting axis bending machine precision).
2. Daily working hours of the machine (electro-hydraulic bending machine offers higher efficiency, reducing labor costs).
3. Experience level of machine operators (twisting axis bending machine requires trial and error based on experience, while the electro-hydraulic bending machine is controlled by a system and is simple and convenient to operate).
4. Previous experience with twisting axis bending machines, understanding the frequency of malfunctions, as frequent malfunctions can reduce work efficiency and delay project timelines (electro-hydraulic bending machines have extremely low failure rates).
There are various types of bending machines available in the market, each with different configurations and corresponding systems. Among them, the twisting axis bending machine and the electro-hydraulic bending machine are often compared due to their similar functions but different components, systems, and prices. So, how can we choose a high-performance, cost-effective, and user-friendly bending machine that will never fall behind from the many options available? In the following discussion, we will explore the differences between the twisting axis bending machine and the electro-hydraulic bending machine from multiple perspectives.
Different Structural Principles
The two machine types have different design principles, which result in different structures for ensuring synchronous movement of the bending slider on both sides. The twisting axis bending machine uses a twisting axis to connect the left and right swing arms, forming a twisting axis that forces the synchronous movement of the cylinders on both sides. Therefore, the twisting axis bending machine employs a mechanical forced synchronization mechanism, and the parallelism of the slider cannot be automatically checked and adjusted. On the other hand, the electro-hydraulic bending machine installs a grating ruler on the slider or the bed, and the CNC system can analyze the synchronous condition of both sides of the slider through the feedback information from the grating ruler. If any deviation occurs, the CNC system will make adjustments through proportional electro-hydraulic servo valves to ensure the synchronous movement of the slider. The CNC system, hydraulic control valve group, and grating ruler together form a closed-loop feedback control system for the electro-hydraulic bending machine.
Workpiece Precision
The parallelism of the slider determines the angle of the workpiece. In the twisting axis bending machine, the slider synchronization is mechanically maintained without real-time error feedback, and the machine itself cannot make automatic adjustments, resulting in poor machining precision. Additionally, its off-load capacity is also inferior because the twisting axis bending machine relies on the twisting axis to force the synchronous movement of the cylinders on both sides. Prolonged off-load operation can cause deformation of the twisting axis. On the other hand, the electro-hydraulic bending machine achieves synchronous control of the slider through a proportional electro-hydraulic valve group and real-time error feedback from the grating ruler. If any deviation occurs, the system adjusts the slider through the proportional valve to maintain synchronization, thereby improving machining precision.
Bending Process
Operating Speed
Three factors determine the operating speed of the machine: (1) the speed of the slider, (2) the speed of the back gauge, and (3) the bending steps. The twisting axis bending machine uses cylinders with a ratio of 6:1 or 8:1, resulting in slower speeds. In contrast, the electro-hydraulic synchronous bending machine uses cylinders with a ratio of 13:1 or 15:1, enabling faster speeds. Therefore, the downward speed and return speed of the slider in the electro-hydraulic bending machine are much higher than those of the twisting axis bending machine. While the twisting axis bending machine has functions for both fast and slow downward movement of the slider, the fast downward and return speeds are only 80mm/s, and the transition between fast and slow movements is not smooth. The speed of the back gauge is only 100mm/s. In comparison, the electro-hydraulic bending machine has functions for both fast and slow downward movement of the slider, with fast and return speeds reaching 200mm/s, and the transition between fast and slow movements is smooth, greatly improving production efficiency. At the same time, the speed of the back gauge can reach 400mm/s.
Comparison of Operating Speed
Mechanical Strength
Due to its design, the twisting axis bending machine cannot handle off-center bending. Prolonged off-center bending can cause deformation of the twisting axis. In contrast, the electro-hydraulic synchronized CNC bending machine does not have this issue. The Y1 and Y2 axes on both sides operate independently, allowing for off-center bending.
Twisting Axis in Twisting Axis Bending Machine
Actual Operation
Most twisting axis bending machines do not come with CNC systems or V-axis compensation. Therefore, when processing based on drawings, they rely on the experience of skilled workers to make trial bends. If the results are not satisfactory, further trials are needed, resulting in waste material and limited options for skilled workers, whose wages are usually higher. Of course, a manual compensation system can be added if necessary. On the other hand, the electro-hydraulic bending machine is controlled by a professional CNC system with V-axis compensation, making the operation simple and requiring less experience from the workers. It has a simulation bending function, eliminating the need for trial bending and only requiring the input of dimensional corrections based on the drawings for direct bending.
Manual Compensation System (top right) and Electric Axis Compensation (bottom left)
CNC Axes
The performance of the twisting axis bending machine deteriorates as the number of controlled axes increases. Usually, only the X and Y axes are controlled. The electro-hydraulic bending machine is not limited by the number of axes and can have a minimum of 3+1 axes, allowing for automated program design to meet high requirements, such as 4+1, 5+1, 6+1, 7+1, 8+1 axes, and so on. With the coordination of multiple axes, the workpiece can be clamped once on the bending machine, and automatic tool change, rotation of the spindle head, rotation of the worktable, and other operations can be performed to complete complex processes and multi-surface machining. This not only improves the surface finish but also greatly enhances efficiency.
Commonly Used Multi-Axis Options in Electro-Hydraulic Bending Machines
Advanced Options
The twisting axis bending machine can be equipped with some improved configurations, such as ordinary quick clamps, manual compensation, up and down stop fingers, ball screws and linear guide back gauges, oil coolers, and light curtains for protection. However, the electro-hydraulic bending machine can not only be equipped with these basic configurations but also offers a variety of advanced accessories. For example, it can be equipped with a higher-quality TYOKKO or AMADA quick clamps in addition to the standard quick clamps. The up and down stop fingers can be manually operated or equipped with an electric Z-axis stop finger that runs on a guide rail using an AC motor. The light curtain protection can be replaced with a more sensitive and secure laser protection. Other options include a servo pump control system that offers advantages such as energy efficiency, low noise, high stamping speed, higher accuracy, and lower oil consumption; a robotic arm that significantly improves production efficiency; hydraulic clamping systems; and dynamic material supports and laser angle detectors.
Twisting Axis Bending Machine (left) and Electro-Hydraulic Bending Machine (right) with Common Optional Configurations
The main differences between the electro-hydraulic bending machine and the twisting axis bending machine lie in whether they have closed-loop feedback and electro-hydraulic compensations. The twisting axis bending machine adjusts the cylinder stroke mechanically, while the electro-hydraulic bending machine controls the stroke hydraulically. The twisting axis bending machine relies on a balance shaft for control, while the electro-hydraulic bending machine achieves synchronization through servo proportional valves on both sides. The electro-hydraulic bending machine combines the advantages of electrical and hydraulic systems, offering high control precision, fast response speed, high output power, flexible signal processing, and easy implementation of various parameter feedback. The efficiency of an electro-hydraulic bending machine can be equivalent to two or three twisting axis bending machines.
In conclusion, when selecting a bending machine, it is important to consider the actual processing requirements. The electro-hydraulic servo synchronized bending machine offers high precision with real-time error feedback and has a stronger resistance to off-center loads. The twisting axis synchronized bending machine has lower precision without error feedback and has a weaker resistance to off-center loads. The electro-hydraulic bending machine is more complex and has a higher price. Based on the information provided above, you can choose a suitable bending machine based on the following specific aspects:
1. Precision requirements for the workpiece (deviation in twisting axis bending machine precision).
2. Daily working hours of the machine (electro-hydraulic bending machine offers higher efficiency, reducing labor costs).
3. Experience level of machine operators (twisting axis bending machine requires trial and error based on experience, while the electro-hydraulic bending machine is controlled by a system and is simple and convenient to operate).
4. Previous experience with twisting axis bending machines, understanding the frequency of malfunctions, as frequent malfunctions can reduce work efficiency and delay project timelines (electro-hydraulic bending machines have extremely low failure rates).
