Common Faults Of Solenoid Valves

The solenoid valve is composed of a solenoid coil and a magnetic core, and is a valve body containing one or more holes. When the coil is energized or de-energized, the operation of the magnetic core will cause the fluid to pass through the valve body or be cut off to achieve the purpose of changing the direction of the fluid. The electromagnetic components of the solenoid valve are composed of fixed iron core, moving iron core, coil and other components; the valve body is composed of sliding valve core, sliding valve sleeve, spring base and other components. The electromagnetic coil is directly installed on the valve body, and the valve body is enclosed in a sealed tube, forming a simple and compact combination. The solenoid valves commonly used in production include two-position three-way, two-position four-way, two-position five-way, etc. Here we first talk about the meaning of two positions: for the solenoid valve, it is energized and de-energized, and for the controlled valve, it is open and closed.
The fault of the solenoid valve will directly affect the action of the switching valve and the regulating valve. Common faults include the failure of the solenoid valve to act, which should be checked from the following aspects:
1. The solenoid valve wiring head is loose or the wire head is detached. The solenoid valve must not be energized, and the wire head can be tightened.
2. If the solenoid valve coil is burned out, you can remove the wiring of the solenoid valve and measure it with a multimeter. If it is open, the solenoid valve coil is burned out. The reason is that the coil is damp, causing poor insulation and magnetic leakage, resulting in excessive current in the coil and burning, so rainwater should be prevented from entering the solenoid valve. In addition, the spring is too hard, the reaction force is too large, the number of coil turns is too small, and the suction force is insufficient, which can also cause the coil to burn out. In emergency treatment, the manual button on the coil can be turned from the "0" position during normal operation to the "1" position to open the valve.
3. The solenoid valve is stuck: The matching clearance between the sliding valve sleeve and the valve core of the solenoid valve is very small (less than 0.008mm), and it is generally assembled in one piece. When mechanical impurities are brought in or there is too little lubricating oil, it is easy to get stuck. The treatment method is to use a steel wire to poke it from the small hole in the head to make it rebound. The fundamental solution is to remove the solenoid valve, take out the valve core and valve core sleeve, and clean it with CCI4 so that the valve core can move flexibly in the valve sleeve. When disassembling, attention should be paid to the assembly sequence of each component and the external wiring position so that the reassembly and wiring are correct. It is also necessary to check whether the oil mist spray hole is blocked and whether the lubricating oil is sufficient.
4. Leakage: Leakage will cause insufficient air pressure, making it difficult to open and close the forced valve. The reason is that the sealing gasket is damaged or the slide valve is worn, causing several cavities to leak air. When dealing with the solenoid valve failure of the switching system, the appropriate time should be selected, and the solenoid valve should be handled when it is de-energized. If it cannot be handled within a switching gap, the switching system can be suspended and handled calmly.