Analysis of 6 common problems with electromagnetic proportional directional valves

The proportional directional control valve is subject to loss during normal use. When the loss reaches a certain level, it will malfunction and become unable to work.

1. The proportional reversing valve solenoid tube push rod wears out and becomes shorter.

The function of the push rod in the solenoid tube of the proportional reversing valve is to push the valve core to move when the armature moves. The push rod and the valve core are not integrated into one body. Therefore, wear is bound to occur during constant contact.

After long-term high-frequency commutation, it may wear and become significantly shorter. At this time, the valve core is not reversed in place, affecting the normal operation of the Solenoid directional valve. The fault can be solved by simply replacing the push rod. Note that the new push rod specifications and dimensions should be consistent with the original accessories.

2. The electromagnet is damaged (burned)

Burnt out electromagnet is also one of the common faults of the electromagnetic reversing valve. One of the main reasons is quality problems, such as poor processing of the iron core, too low wire diameter standards, and easy overheating.

Failures caused by quality reasons can usually be clearly detected within a few hours of the solenoid reversing valve being powered on. For coil failures after working for a period of time, most of them are caused by the use environment.

3. Wear of the outer diameter of the valve core

This is the same as the wear of the bore in the valve body. Especially if the oil contains too many impurities, it will aggravate the wear of the solenoid valve core.

Although this kind of wear cannot be completely avoided, in order to extend the service life of the solenoid reversing valve and maintain good working condition, the cleanliness of the hydraulic oil should be checked regularly and excessive contamination of the hydraulic oil should be dealt with in a timely manner.

The three-wing solenoid reversing valve core is made of a unique material with a hardness of over HRC60. It has better wear resistance than ordinary solenoid reversing valve cores, so its lifespan is also greatly enhanced.

4. The return spring is fatigued or broken.

This type of failure has a certain relationship with the material selection of the spring. The electromagnetic reversing valve uses imported piano wire springs with a black surface treatment, which has good elasticity and fatigue resistance.

The enhanced surface treatment process can effectively prevent the spring from being corroded and have a long service life. If such a fault occurs, both springs must be replaced at the same time, and the length must match the design value of the electromagnetic reversing valve.

5. Hole wear in the valve body

There is frequent back-and-forth movement between the valve core and the hole in the valve body. Although the valve core of the solenoid directional valve is designed with an oil groove, which can fill the contact surface with oil to a minimum and reduce friction. However, according to the working nature of the solenoid directional valve, the solenoid directional valve has The wear of the bore in the valve body cannot be completely avoided.

The body of the solenoid valve is made of ductile iron. Different from ordinary solenoid reversing valves, the three-wing uses a unique raw material ratio to strengthen the hardness of the valve body, which to a certain extent delays the wear and deformation of the holes in the valve body.

Wear in the bore in the valve body can be repaired or replaced as needed. When replacing, you need to pay attention to whether the new valve body can match the relevant components of the original solenoid directional valve, such as solenoid tubes, sealing rings, etc.

6. Caused by uncommon problems

The above are the five most common problems with electromagnetic reversing valves. There may also be other uncommon problems, such as unstable voltage, current, and large shock fluctuations, which may lead to burnout.

And according to the working principle of the electromagnet, when the electromagnetic reversing valve core is stuck, causing the armature to be unable to move into place after the electromagnet is energized, the coil temperature will rise sharply and easily cause burnout in a short period of time. This type of failure accounts for Most solenoid valve coil failures.

Therefore, in actual maintenance, if a coil burns out, you should first check whether the solenoid valve is working smoothly. After troubleshooting such as valve core jamming, replace the coil with a new one. Otherwise, the coil may still burn out after replacement.