CNC busbar bending machine: the difference between servo drive and hydraulic drive

The servo drive system uses servo motors and precision transmission devices to achieve precise control, while the hydraulic drive system generates power through hydraulic pumps and hydraulic cylinders. These two drive methods have their own characteristics and are suitable for different processing requirements and environmental conditions.

The servo-driven CNC busbar bending machine mainly drives the high-precision ball screw through the servo motor to realize the movement of the slider. The servo motor has the characteristics of fast response, high precision and high efficiency. Its drive system structure is relatively simple, mainly composed of servo motor, ball screw and CNC system. Taking a certain model of servo-driven CNC busbar bending machine as an example, the rated torque of its servo motor can reach 50Nm, and the lead accuracy of the ball screw is 0.01mm, which can achieve extremely high positioning accuracy.

The hydraulic-driven CNC busbar bending machine relies on the hydraulic system, drives the hydraulic pump through the motor, and uses high-pressure oil to push the hydraulic cylinder to realize the movement of the slider. The hydraulic system usually includes components such as hydraulic pump, oil tank, control valve and hydraulic cylinder, and the structure is relatively complex. For example, the working pressure of the hydraulic pump can reach 150bar, and the stroke of the cylinder is generally between 100mm and 500mm depending on the model.

When the servo drive system is in standby mode, the motor does not run and energy is consumed only during the actual processing process, so it has a significant energy-saving effect. Data shows that the energy consumption of the servo drive system in standby mode is only about 10% of that of the hydraulic drive system. In contrast, when the hydraulic system is in standby mode, the hydraulic pump still needs to continue to operate to maintain the system pressure, resulting in energy waste. In addition, the hydraulic system requires the use of hydraulic oil, which not only increases operating costs, but may also cause environmental pollution due to oil leakage. The servo drive system does not need to use hydraulic oil, which fundamentally avoids this problem and is more environmentally friendly.

The servo drive system can accurately control the stroke and speed of the slider through closed-loop control, with extremely high control accuracy and repeatability. During the CNC busbar bending process, the servo system can adjust the bending speed and pressure in real time according to different materials and thicknesses to ensure high-quality bending effects. For example, its positioning accuracy can reach ±0.01mm, and the repeat positioning accuracy is ±0.005mm. Although the hydraulic drive system can also achieve high control accuracy, the viscosity and temperature changes of the hydraulic oil will affect the system performance, resulting in its control accuracy and repeatability being slightly inferior to the servo system. In addition, the fast response characteristics of the servo drive system make the processing speed faster, thereby improving production efficiency. Some high-performance servo-driven CNC busbar bending machines can achieve a processing speed of more than 200 times per minute.

The hydraulic system has a complex structure and involves multiple hydraulic components, such as pumps, valves, and seals. These components are prone to wear and aging during long-term use and need to be replaced and maintained regularly, with high maintenance costs. The average maintenance cost of the hydraulic system is about 15% to 20% of the total equipment cost per year. At the same time, hydraulic oil contamination and leakage problems will also increase maintenance difficulty and cost. The servo drive system has a relatively simple structure, and maintenance is mainly concentrated on components such as motors and ball screws. The maintenance cost is low, generally only 50% to 70% of the hydraulic system. In addition, the servo system does not require the use of hydraulic oil, avoiding oil contamination and leakage problems, and has a relatively long service life.

The servo drive system is suitable for high-precision and high-efficiency bending processing, and can meet the processing requirements of various complex parts. Although the hydraulic drive system can also achieve high bending accuracy, due to its relatively slow response speed, it is more suitable for medium- and low-precision and large-volume bending processing. In addition, the hydraulic system has a greater advantage in pressing large or long workpieces, and can provide greater pressure and stroke.

During the operation of the hydraulic system, the hydraulic pump and valve body will generate a lot of noise, and the general noise level is between 80dB and 90dB. At the same time, the hydraulic oil flowing under high pressure will also generate heat, causing serious heating of the system, and the oil temperature can reach above 60℃. Since the servo drive system adopts electrical drive, the noise and heating problems are relatively small, the noise level is generally less than 70dB, and the system heat generation is also low, which not only improves the working environment, but also helps to increase the service life and stability of the equipment.

Based on our nearly 20 years of experience in the busbar machine manufacturing industry, we recommend customers to choose a busbar bending machine factory with strength and mature technology. In addition to providing you with professional and complete bending technology solutions, after-sales service is also valued by these CNC busbar machine suppliers.

• EHRT www.ehrtnorthamerica.com

• PAYAPRESS www.payapress.com

• SUNSHINE www.busbarmachine.co

• MAC www.busbarmac.com