Back Hoe Excavators Hydraulic Spare Parts Hydraulic Directional Manual Control Valve SD8-5

Back-hoe Excavators hydraulic spare parts hydraulic directional manual control valve SD8-5

Application :

Cranes, Telescopic boom fork lifts, Back-hoe Excavators and Compactors.

A hydraulic valve is an element used to control the pressure, flow, and direction of fluid in a hydraulic system.

First, Classification

1. According to the function, it can be divided into pressure control valve, flow control valve and directional control valve. Pressure control valves are used to control the pressure in the system, such as relief valves, pressure reducing valves, etc. Flow control valves are used to regulate the flow in the system, such as throttle valves, speed control valves, etc. Directional control valves are used to change the flow direction of fluids, such as check valves, reversing valves, etc.

2. According to the structural form, it can be divided into spool valve, pop valve, ball valve, etc.

Second, the working principle

Hydraulic valves control the flow direction, pressure, and flow of hydraulic oil by changing the relative position between the spool and the seat. When the valve core is affected by external control signals (such as electromagnets, mechanical forces, etc.), the corresponding displacement will be generated, which will change the opening and flow area of the valve port to achieve the control of the hydraulic system.

Third, the field of application

It is widely used in construction machinery, metallurgical equipment, mining machinery, injection molding machinery, ships, aerospace and other fields. For example, in construction machinery, hydraulic valves are used to control the lifting, luffing and slewing of cranes; In injection molding machinery, hydraulic valves are used to control the processes of mold clamping, injection, pressure packing, and demoulding of injection molding machines.

Fourth, features

1. High control accuracy: It can accurately control the pressure, flow and direction of the hydraulic system.

2. Fast response: It can quickly respond to the control signal and realize real-time control of the hydraulic system.

3. High reliability: It has good sealing performance and anti-pollution ability, and can operate stably for a long time in harsh working environments.

4. Compact structure: small size, light weight, easy to install and maintain.

5. Troubleshooting methods for hydraulic valves

Troubleshooting pressure control valves

1. Relief valve failure

The pressure cannot be adjusted: check whether the spring is damaged or deformed, whether the valve core is stuck, and whether the damping hole is blocked. If there is a problem with the spring, replace the spring; If the valve core is stuck, the valve core and valve body need to be cleaned; If the damping hole is blocked, clean the damping hole.

Large pressure fluctuations: It may be that the spool is not well matched with the seat or there are impurities in the oil. The spool and seat can be grinded, the hydraulic system can be cleaned and the fluid can be replaced.

Severe leakage: Check the seal for damage, and replace the seal if it is damaged.

2. Failure of the pressure reducing valve

Unstable outlet pressure: Check if the spool is stuck and if the spring is failing. The treatment method is the same as the corresponding fault of the relief valve.

Leaks: Check the seal and replace the damaged seal.