What are the faults of single-head solenoid reversing valve?

Common faults of single-head solenoid directional valves mainly include unreliable commutation, coil failure, leakage problems, shock and vibration, and installation and assembly problems, as follows:

The reversal is unreliable or cannot be reversed:

Electromagnet problems: Burned out electromagnet coils, insufficient electromagnet driving force or magnetic leakage, electrical circuit failures, etc. may cause the electromagnet to fail to work properly, thereby affecting commutation. For example, a coil short circuit or open circuit may be caused by coil quality problems, excessive power supply voltage, repeated shocks, or excessive mechanical vibration.

Pilot solenoid valve failure: the valve core and valve body hole are stuck, the spring is bent sideways, etc., which may also lead to unreliable commutation. This is usually caused by poor geometric accuracy of the parts, tight fit between the valve core and the valve hole, or excessively dirty oil.

The main valve core is stuck: The geometric accuracy of the valve core and the valve body is poor, the valve core and the valve hole are too tight, there are burrs on the valve core surface, or there is no oil in the control oil line, etc., which may cause the main valve core to be stuck, thus affecting the direction change.

Other factors: such as high temperature and high pressure in the system and impurities in the machine causing the slider to deform and become stuck, residual magnetism to attract the valve core or become stuck, capillary tube on the valve to be clogged or broken, etc., which may also lead to unreliable or impossible reversal.

Coil failure:

Coil overheating or burnt out: This may be caused by reasons such as too high power supply voltage, too high commutation frequency, too long extension length of the push rod and improper coordination with the stroke of the electromagnet, poor insulation of the electromagnet coil, etc.

Coil open circuit or short circuit: In addition to the above reasons, coil open circuit or short circuit may also be caused by coil aging, wear or external force damage.

Leak issues:

External leakage: mainly occurs at the joint surface between the solenoid reversing valve and the installation floor, the oil port of the tubular valve or the threaded joint of the process plug, the fitting surface between the solenoid and the valve body, etc. This is usually caused by loose connecting screws, failed or missing seals, too high oil pressure, or rough mounting surfaces.

Internal leakage: The main reason is that the machining accuracy or damage between the valve core and the valve body hole results in excessive clearance, valve core offset, unqualified valve core size or excessive oil temperature, etc.

Shock and Vibration:

Reversing impact: Large-diameter solenoid reversing valves may produce impact due to their large electromagnet size and fast closing speed. Hydraulic reversing valves may also cause impact due to excessive control flow and too fast movement of the valve core. In addition, the one-way valve steel ball in the one-way throttle valve is missing or broken, which may also cause impact.

Vibration: Loose screws holding the electromagnet in place can cause vibration.

Installation and assembly issues:

Poor installation: Such as uneven tightening torque of the installation screws, 'uneven' pipes connected to the valve body, etc., may cause the electromagnetic reversing valve to work abnormally.

Assembly problems: For example, poor coaxiality between the solenoid core and the valve core axis, too long or too short push rod, etc. may also affect the performance of the solenoid directional valve.