Excavator Control Valve Spool

Excavator control valve spool as a key component in the hydraulic system, its performance and stability directly affect the operating efficiency and safety of the entire hydraulic system.

1. Definition and Role
Excavator control valve spool , as the name suggests, is installed inside the cylinder for controlling the hydraulic flow and pressure of the key components.

It realizes the control of pressure oil circulation or blocking on both sides of the cylinder by changing the state of the internal channel, so as to regulate the movement of the cylinder.

Excavator control valve spool has the advantages of fast, sensitive, energy-saving, safety and so on, and is widely used in machinery manufacturing, petroleum, chemical industry, metallurgy, construction, shipping and other fields.

2. Classification
According to the different control functions and structural forms, the cylinder spool valve can be generally divided into the following types:

One-way spool valve:

mainly used for one-way flow control in the hydraulic system, to prevent reverse flow of hydraulic fluid, to ensure the stability and safety of the system.
Bidirectional spool valves: 

for hydraulic cylinders before and after the sequence of control, can adjust the direction of movement of the cylinder according to the need to achieve a complex sequence of action.
Cartridge spool valve:

with more complex functions, can be used for hydraulic cylinder flow, pressure and direction of a variety of control, to meet the needs of high-precision, high-demand hydraulic control.
3. Structure
Cylinder spool usually consists of valve seat, spool body, spring, sealing elements and other parts.

Spool body is mostly cylindrical or cylindrical, using wear-resistant, corrosion-resistant alloy materials such as stainless steel, copper alloy, titanium alloy, etc., to ensure its stability and durability in poor working conditions.

The sealing element is made of highly elastic and wear-resistant materials, such as polyurethane, to ensure the sealing performance of the valve.

4. Working Principle
The working principle of the excavator control valve spool is based on the mechanics of hydraulics.

When the hydraulic fluid enters the cylinder through the hydraulic interface, the spool will move up and down or rotate in the valve seat according to the control signal of the system and the change of hydraulic pressure, thus changing the size and direction of the valve passage.

Specifically, when the hydraulic pressure acts on the valve spool, the valve spool will overcome the resistance of the spring to move upward (or rotate), open the valve channel, so that the hydraulic fluid can circulate; when the hydraulic pressure is reduced or disappears, the spring will push the valve spool back to its original position (or rotate back to the initial position), close the valve channel, preventing the further flow of hydraulic fluid.

5. Common Failures and Maintenance Methods
Excavator control valve spool in the use of the process may encounter blockage, jamming, leakage and other common failures.

For these failures, you can take the following repair methods:

Blockage:

mainly due to impurities in the hydraulic fluid or foreign matter blocking the valve channel.

At this time, you need to disassemble the valve spool for cleaning, remove the blockage, and check whether the sealing element is damaged, if necessary, then replaced.
Stuck:

usually due to the excavator control valve spool and the valve seat between the fit gap is too small or poor lubrication.

This can be solved by adjusting the mating gap, increasing the lubricant or replacing badly worn parts.
Leakage:

Leakage is one of the common failures of excavator control valve spool and may be caused by aging, damaged or improperly installed sealing elements.

It is necessary to check and replace damaged sealing elements, ensure the flatness and cleanliness of the sealing surface, and install the spool and sealing elements correctly.
6.  Maintenance and Repair
In order to extend the service life of the cylinder spool and maintain its good working performance, regular maintenance and repair is required.

Specific measures include:

Regularly check the oil quality and oil level of the hydraulic system to ensure the cleanliness and adequacy of the hydraulic oil.
Regularly clean the oil cylinder and spool valve and other components to remove the dirt and impurities attached to the surface.
Check and adjust the fit gap and sealing performance between the spool and valve seat to ensure the tightness of the valve.
Regularly inspect and replace parts and sealing elements that are subject to severe wear and tear to prevent malfunctions caused by damaged parts.

Overview of company

Certificates

Factory

Service：

1.Sample service: samples can be provided according to customers’ instruction.

2. Customized services: goods can be customized according to customers’demand.

3. One year warranty, some additional products will be supplied next time if they are in bad condition now.