Matters needing attention in adjusting hydraulic system pressure of hydraulic press

- Jun 05, 2020-

1. Pay special attention to the filtering and cleaning of the oil circuit. Before the hydraulic machine enters the servo valve, it is necessary to install a fine filter with a filtering accuracy of less than 5.

2. After the installation of all hydraulic servo systems, it is necessary for the four-column hydraulic machine manufacturer to completely clean the oil circuit before the valve is installed in the system, and to investigate the purification of the filter element. Remove the filter after 24-36h of the system, clean or replace it Remove the filter element.

3. Welding type joints are not allowed for hydraulic pipelines, and it is recommended to use card sleeve type 24 degree cone structure type joints.

4. Before installing the servo valve, the four-column hydraulic machine manufacturer shall not adjust the installation at will.

5. The installation surface of the servo valve should be smooth, straight, and clean.

6. When installing the servo valve, the four-column hydraulic machine manufacturer should check whether the installation surface is dirty; whether the oil inlet and outlet are well connected; whether the O-ring is defective; whether the positioning pinhole is accurate. When installing the servo valve on the connecting plate, the connecting screw should be tightened evenly. Before connecting the circuit, pay attention to check the connection column, and then enter the polarity check after everything is normal.

7. The oil tank of the servo system must be sealed with air filter and magnetic oil filter. It is necessary to change the new oil through strict filtration.

8. The servo valve should be used strictly in accordance with the conditions stated in the rules of the book.

9. The hydraulic oil is changed regularly, and the oil is changed every six months, and the oil should try to stick to the task within the range of 40-50 degrees.

10. When the system has serious shortcomings, the four-column hydraulic machine manufacturer should first check and sweep out the electrical and servo valve unpredictable links, and then check the servo valve

The principle of the system diagram of the pressure-maintaining circuit for automatic hydraulic oil filling:

When the start button is pressed, the electromagnet 1YA is energized. When the directional valve 6 is connected to the circuit, the upper chamber of the hydraulic cylinder becomes a pressure chamber. When the pressure reaches the predetermined lower limit value, the pressure relay 11 announces a signal to switch the directional valve to medium. At this time, the hydraulic pump is unloaded, and the hydraulic cylinder is maintained by the reversing valve M-type neutral function. When the pressure in the upper chamber of the hydraulic cylinder drops to the predetermined upper limit value, the pressure relay announces a signal again, so that the right position of the directional valve is connected to the circuit. At this time, the hydraulic pump replenishes the upper chamber of the hydraulic cylinder to increase its pressure. During the return stroke, the solenoid valve 2YA is energized, the left side of the directional valve is connected to the circuit, and the piston quickly withdraws upward.

Matters needing attention in adjusting the hydraulic system pressure of four-column hydraulic press:

1. The system pressure cannot be higher than the pressure of the pump unless there is a booster.

2. The internship pressure of the pump depends on the size of the load and is automatically formed, not adjusted. The given pressure should be understood as the pressure of normal tasks.

3. Reduce the pressure of the overflow valve, block the outlet of the pump with the throttle valve directional valve, etc., and dispatch the overflow valve, the pump outlet pressure will rise until the required value.