Intake valve cannot open fault

Quanzhou failure analysis

In Quanzhou in the past two days, I was debugging an air compressor. I encountered such a problem. The unit was operating normally for the first time. However, after shutting down and turning on, the unit was abnormal and could not pump air. At present, it can be guaranteed that the original electrical appliances are normal. ,

One: After the intake filter was removed, and then turned on, it was found that the intake valve could not be opened, and the motor was overloaded, the unit was air-cooled 4.5/7, and the motor was 30KW.

Second, disassemble the micro air inlet connector and find that the gas in the machine head is leaking out (at this time, the unit has been shut down for 15 minutes, and the internal pressure should be equal to the air pressure). It can be determined that the internal pressure of the unit cannot be vented, causing the internal pressure. If the pressure is too high, the machine is overloaded. Now repair the micro air inlet, remove the pipe connecting the vent pipe to the atmosphere, and turn it on. The pipe is in the power-on and unloaded state, and it is also inhaled after being loaded, and turned off to unload. Still inhaling, it can be preliminarily determined that the normally closed solenoid valve is broken or the vent connector is blocked.

Three: Turn on again, when the unit is loaded, quickly unscrew the connector that is connected to the normally closed solenoid valve, and find that the intake valve is open. After 10 minutes of normal opening, after turning off the load, it is found that the normally closed solenoid valve is opened and deflated. When the normally closed solenoid valve is open to the atmosphere, it has been opened three times in a row, and the unit has no abnormality.It is determined that the solenoid valve is not broken, but the self-made vent connector is blocked; 4: Unscrew the empty connector, and the small eye of the connector is vented. The blockage is very solid.After venting the joints, cleaning them, installing them, and turning them on again, the unit has no abnormalities, and the unit has been turned on and off for five times, and the unit has no abnormalities.

Analysis shows that after the self-made joint is blocked, there will be an unloading process from the start of the unit to operation. The main problem is concentrated in this unloading process. The reason is that during unloading, the normally open solenoid valve is closed and the normally closed solenoid valve is open. A small amount of air enters the separator, and a part of the air passes through the control tube to the normally closed magnetic valve, and passes through the spring end of the intake valve. Due to the clogging of the vent connector, the gas bears against the intake valve piston, causing the air pressure at both ends of the piston to be equal, so that , The intake valve cannot be opened even in the loaded state. Please leave a message, my colleagues.