Summary of Hydraulic System and Hydraulic Component Problems

01

The hydraulic system hasn't been used for a long time. After starting it up this time, the vibration is particularly severe and the noise is very loud. I don't know why.

Summary: It may be due to prolonged inactivity, causing nitrogen leakage in the accumulator, which is not reducing pulsation. Check the nitrogen pressure and replenish it or replace the bladder. The noise is caused by excessive vibration; it will disappear once the vibration is removed.

02

The hydraulic cylinder is not working properly; it can only extend but not retract. What is the problem?

Summary: Check if oil is exiting from the other end of the cylinder, whether the solenoid valve is reversing, and whether internal leakage in the cylinder is particularly severe. Check if the return oil line is blocked by foreign objects.

03

What causes high starting pressure in hydraulic cylinders? What are the dangers? How to solve it?

High starting pressure in hydraulic cylinders is related to the manufacturing quality of the cylinder (such as bent piston rod, bent cylinder barrel, etc.), the type of seal, and installation factors. For servo cylinders, high starting pressure will affect their dynamic characteristics. For ordinary hydraulic cylinders, the starting pressure requirement is not as strict as for servo cylinders, but it should not be too high. If high starting pressure is detected, the dimensions of the cylinder parts need to be carefully remeasured, and the installation quality of the seals checked.

Summary: 1. Excessive internal resistance. 2. Mechanical fault in the external actuator.

The starting pressure of a hydraulic cylinder is related to its design structure and the contact area between the oil port and the piston. For example, the size of the oil port determines the initial contact area of ​​the piston, resulting in a higher starting pressure. A machined contact area cavity (starting pressure cavity) between the oil port and piston will have a lower starting pressure.

04

What are some good suggestions for synchronizing hydraulic cylinders in a hydraulic system?

Summary: Adding a one-way throttle valve to the branch line is relatively inexpensive. For higher requirements, adding a flow divider throttle valve is more expensive but more effective.

05

What are the main reasons for the particularly high maintenance rate of hydraulic systems?

The main reason is the harsh environment. Hydraulic systems are relatively precise devices, requiring regular maintenance. Good oil quality is essential; filtering is necessary during oil filling, and the system seals must be in good condition. Various testing equipment should be complete, and professional personnel are needed to record and maintain the system's operation.

06

What to do if the hydraulic cylinder's movement is irregular?

Summary:

1. It may be due to air mixed in the hydraulic lines. The source of the air needs to be located, cleaned, inspected, and components reinstalled or replaced.

2. The cylinder may be severely worn, requiring repair or replacement.

3. Irregular switching of the solenoid valve requires inspection of the electric furnace section.

4. Malfunction or improper adjustment of the amplifier in the electro-hydraulic servo or proportional valve.

One pump is moving while the other is not. When the first pump fails, the second starts working. What is the best connection between the two hydraulic stations? Everything else is designed correctly; only the connection between the two hydraulic stations is missing.

The oil pump needs time to start. During the time between the failure of the first hydraulic station and the start of the second hydraulic station outputting normal pressure, its pressure needs to be maintained.

Summary: Use a pressure relay to convert the pressure signal into an electrical signal and transmit it to the standby pump.