Control system of four-column hydraulic press

Four-column hydraulic press is a mechanical equipment that uses the static pressure of hydraulic oil delivered by oil pump to process metal, plastic, rubber, wood, powder and other products. Four-column hydraulic press, also known as oil press, is a machine that uses liquid pressure transmission based on Pascal's law. There are many types. Of course, the uses are also diverse according to needs. For example, according to the type of liquid that transmits pressure, there are two major categories: oil press and water press. The total pressure generated by the water press is relatively large, and it is often used for forging and stamping. Forging hydraulic press is divided into die forging hydraulic press and free forging hydraulic press. Die forging hydraulic press requires a die, while free forging hydraulic press does not use a die.

 

Working principle of the control system: The control system of the four-column hydraulic press realizes precise control of the hydraulic press through the coordinated work of the electrical control unit and the hydraulic control unit. The operator inputs the required working parameters through the human-machine interface, and the PLC receives these parameters and sends control signals according to the preset control logic.

 

After receiving the control signal, the hydraulic control unit adjusts the working state of the hydraulic pump and controls the flow and pressure of the hydraulic oil. The sensor monitors the working status of the hydraulic press in real time and feeds the data back to the PLC to ensure that the system operates within a safe range.

 

The control system of the four-column hydraulic press mainly includes the following aspects:

 

1. Oil temperature signal. The oil temperature has a great influence on the performance of each component of the hydraulic system of the four-column hydraulic press. For the filter press system, it is generally appropriate to control it below 60°C.

 

2. The oil tank level signal is an important state parameter in the hydraulic system. The appropriate liquid level plays an important role in the precipitation and filtration of oil bubbles and impurities, as well as stabilizing the oil temperature.

 

3. The hydraulic pump outlet pressure signal. The hydraulic pump is the heart of the four-column hydraulic press. When the plunger pump fails, the pump outlet pressure signal must be abnormal. Therefore, the pressure signal can be used to detect the state of the hydraulic pump.

 

4. The oil filter blockage signal. The oil press uses a return oil filter. The oil filter pressure differential relay sends a signal to judge the condition of the oil filter and the working medium, and provides a switch signal.

 

5. Displacement sensor. The hydraulic cylinder pressure signal is the final reflection of whether the working state of the four-column hydraulic press system is normal or not.

 

6. Pressure sensor at the overflow valve. In the hydraulic system of the hydraulic press, the overflow valve can adjust the rated working pressure of the hydraulic actuator to ensure the normal operation of the system, and also directly affect the working performance and safety of the entire hydraulic system of the hydraulic press.

 

7. The rodless chamber pressure signal of the hydraulic cylinder, the working state and performance of the reversing valve directly affect the pressure change of the hydraulic cylinder.

 

Some abnormal reactions of the four-column hydraulic press reflect problems in the control system. For example, the heating of the plunger pump is due to wear and tear between the pump plunger and the cylinder hole, the oil distribution plate and the cylinder joint surface, which leads to increased internal leakage, and the leakage energy is converted into heat energy to cause heating; and the oil temperature is too high, which is also relatively common. The greater the viscosity of the oil, the greater the friction, and the friction generates heat, causing the oil temperature to rise. In short, the structural composition of the four-column hydraulic press control system is the basis for its efficient and stable operation. Through the coordinated work of the hydraulic control unit, the electrical control unit, the sensor system and the human-machine interface, the four-column hydraulic press can achieve precise control and efficient production.

 

   Dongguan Shengshi Weiye Machinery Technology Co., Ltd. specializes in the production of Forging Press, Deep Drawing Hydraulic Press, Gravity Casting Machine, Four-column Servo Press, C Type Pneumatic Press and other machines. Friends in need are welcome to pay attention and learn more.