Two-way five-way pneumatic solenoid valve

- Oct 08, 2019-

The two-position five-way solenoid valve is an automatic basic component for controlling fluid, and belongs to the actuator; it is not limited to hydraulic and pneumatic. Solenoid valves are used to control the direction of hydraulic flow. The mechanical devices of the factory are generally controlled by hydraulic cylinders, so solenoid valves are used.


       The working principle of the solenoid valve has a closed cavity in the solenoid valve. There are through holes at different positions. Each hole leads to a different oil pipe. The middle of the cavity is a valve. On both sides are two electromagnets. Which side of the magnet coil The electric valve body will be attracted to which side, by controlling the movement of the valve body to block or leak different oil drain holes, and the oil inlet hole is normally open, the hydraulic oil will enter different oil drain pipes, and then pass The pressure of the oil pushes the piston of the cylinder, which in turn drives the piston rod, which drives the mechanical device to move. This controls the mechanical motion by controlling the current of the electromagnet.


Two-way five-way pneumatic solenoid valve

It is inevitable that there will be no failure during the use of the solenoid valve. The working principle of the solenoid valve and the steps of fault inspection, judgment, treatment and maintenance are as follows:


1. Composition and working principle:


a, the composition of the structure: consists of the electrical part and the pneumatic execution part;


b, working principle:


1) When the electrical part is energized, the electromagnetic coil generates electromagnetic force to lift the closing member from the sealing air hole, the compressed air enters the pilot valve, and the pilot valve works; when the power is cut off, the electromagnetic force disappears, and the valve action is reversed;


2) The pneumatic actuator performs the joint movement of the pilot valve piston and the other end of the main piston rod to complete the switching of the two-way five-way.



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Initial state, 1, 2 intake; 4, 5 exhaust; when the coil is energized, the static iron core generates electromagnetic force to make the pilot valve act, and the compressed air enters the valve pilot piston through the air passage to start the piston, in the middle of the piston, seal The circular opening opens the channel, 1, 4 intake, 2, 3 exhaust; when the power is off, the pilot valve is reset under the action of the spring and returns to the original state.


2, fault check, determination method:


a. First determine if the solenoid valve is faulty.


1) Test the pneumatic mechanism. When the power is cut off and checked to ensure that the air supply is normal, press the manual valve open button on the side of the solenoid. If the solenoid valve is open, the valve is normally open. If you leave the button to see if the solenoid valve is switched, if it switches normally, the pneumatic actuator of the solenoid valve works normally.


2) Test the electrical part. Manually rotate the switch on the field distribution box, switch the open position valve to open, and close the valve when closed, indicating that the electrical part is normal. If it is not working, measure whether the electromagnetic coil is burnt or not, and replace it.


3) Troubleshooting method: first check if the air supply is normal, if not, open the air supply valve. Then check whether the solenoid valve is normal and handle it according to the above-mentioned determination method. In an emergency, you can manually open the valve directly with the trachea.


Solenoid valve overhaul considerations:


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a, the piston rod must be flexible. Manually tested, it is easy to press the piston rod. After the hand is released, the piston rod can automatically return to the original position before pressing the spring force. If it does not pop up automatically, clean the dust inside the valve body and the piston rod and handle it with high-quality oil to ensure the piston rod is free.


b. The pilot valve piston should be able to move easily and freely like the piston rod. The treatment method is the same as above.


c. The gas path of the pilot valve must work smoothly. If it is not smooth, it can be used to comb the gas path to ensure smooth and unobstructed airway.


d. The electromagnetic coil is energized under normal conditions, the closing member should be lifted, and there is a sound of suction. If it is not normal to check whether the coil is burnt and if there is any debris inside the closing part, measure and clean up the debris.