One: Introduction of servo hydraulic press:
The new type of servo-driven hydraulic press (servo hydraulic press for short) adopts the "pump-controlled servo" technology, which achieves precise control of flow and pressure through precise control of the torque and speed of the pump. It is mainly composed of electro-hydraulic servo drive, three-phase AC permanent magnet synchronous motor, high-performance dedicated servo pump, pressure sensor, etc. Since the output flow of the oil pump is proportional to the speed of the motor, the pressure in the oil circuit is proportional to the output torque of the motor. Through the double closed-loop control of system pressure and flow, vector control + field weakening control + dedicated PID control algorithm is used to complete the precise control of the pump torque and speed, to achieve accurate supply according to the actual required flow and pressure, and eliminate high pressure throttling The energy loss of the traditional "valve-controlled servo" system overcomes the problem of excessive oil temperature rise caused by high-pressure throttling of the traditional "valve-controlled servo" system, and achieves energy-saving and power-saving effects. At the same time, the system oil temperature is reduced. The highest energy-saving rate is 70%, and the average energy-saving rate is 30%. It is suitable for stamping, die forging, press-fitting, straightening and other processes.
1: Advantages and functions of servo hydraulic press
Folding 1, energy saving:
Compared with ordinary hydraulic machines, servo hydraulic machines do not contain proportional servo valves or proportional pump links in the overall control of the system. Servo-driven hydraulic machines have the advantages of energy saving, low noise, small temperature rise, good flexibility, high efficiency, and convenient maintenance, which can replace the existing ones. Most ordinary hydraulic presses have broad market prospects. Compared with traditional hydraulic presses, the energy-saving effect is significant. According to different processing technology and production cycle, servo-driven hydraulic presses can save 30%~70% of electricity compared with traditional hydraulic presses.
Folding 2, low noise:
Servo-driven hydraulic oil pumps generally use internal gear pumps or high-performance vane pumps. Traditional hydraulic machines generally use axial piston pumps. Under the same flow and pressure, the noise of internal gear pumps or vane pumps is 5dB lower than that of axial piston pumps. ~10dB. The motor of the servo-driven hydraulic press runs at the rated speed during compression and return, and its emission noise is 5dB~10dB lower than that of the traditional hydraulic press. When the slider is fast falling and the slider is stationary, the speed of the servo motor is 0, so the servo-driven hydraulic machine basically has no noise emission. In the pressure-holding stage, due to the low motor speed, the noise of the servo-driven hydraulic machine is generally less than 70dB, while the noise of the traditional hydraulic machine is 83dB~90dB. After testing and calculation, under normal working conditions, the noise generated by 10 servo hydraulic presses is lower than the noise generated by an ordinary hydraulic press of the same specification.
Folding 3. Less heat and cost reduction:
Since the hydraulic system of a servo-driven hydraulic press has no overflow heating and no flow when the slider is stationary, there is no hydraulic resistance heating. The heating value of the hydraulic system is generally 10% to 30% of that of a traditional hydraulic press. Since the system generates less heat, most servo-driven hydraulic presses do not need to be equipped with a hydraulic oil cooling system, and some with larger heat generation can be equipped with a low-power cooling system. Because the pump has the characteristics of zero speed and low heat most of the time, the oil tank of the servo-controlled hydraulic machine can be smaller than that of the traditional hydraulic machine, and the oil change time can be extended. Therefore, the hydraulic oil consumed by the servo-driven hydraulic machine is generally only about 50% of the traditional hydraulic machine.
Folding 4. High degree of automation, good flexibility and high precision:
The pressure, speed and position of the servo-driven hydraulic press are fully closed-loop digital control, with high degree of automation and good precision. In addition, its pressure and speed are programmable to meet the needs of various processes, and it can also realize remote automatic control.
Folding 5. High efficiency:
Through proper acceleration and deceleration control and energy optimization, the speed of the servo-controlled hydraulic press can be greatly increased, and the working cycle is several times higher than that of the traditional hydraulic press, which can reach 10/min~15/min.
