Cause Analysis of Automatic Shutdown of Air Compressor

In the process of using the air compressor, the user of the air compressor will encounter the phenomenon of automatic shutdown during the operation of the air compressor, and find that the temperature of the head of the air compressor is too high. Then, why does the air compressor stop automatically?

The reasons for the fault shutdown caused by high temperature are as follows:

1. environmental ventilation problems, resulting in poor heat dissipation.

1. The air compressor is too close to the wall, and there is no gap between the machine and the wall to dissipate heat.

There is a high temperature heat source near the air compressor, which causes the ambient temperature to rise.

3. When the air compressor is running, the outer wall is open, and the fan cannot form a strong airflow inside to help dissipate heat.

2. radiator blocked. Around the air compressor, there are many environmental impurities such as dust. Under long-term operation, a layer of dust or sludge will adhere to the appearance of the air compressor radiator, resulting in blockage of the internal copper pipe due to long-term accumulation of grease, which greatly affects the heat dissipation effect.

3. oil and gas separator filter element is too dirty. When the oil and gas separator is too dirty, the oil will further affect the circulation due to excessive resistance, which will cause overheating shutdown. We can judge from the pressure difference between before and after loading. If the pressure difference between the two ends is three times that before the air compressor is loaded or the pressure difference reaches 0.1MPa, it needs to be cleaned or replaced to avoid unnecessary accidents.

4. oil filter is too dirty. Too much debris inside the oil filter, resulting in oil can not enter the air compressor according to the normal flow, then the air compressor will continue to heat up due to insufficient cooling and lubrication. Therefore, the oil filter maintenance needs to be replaced.

5. screw compressor lubricating oil level is too low. When the oil level is lower than the lower end of the inspection tube, it needs to be replenished.

6. head pressure is too high. When the head pressure exceeds the rated 12MPa, long-term operation will automatically stop due to excessive load. Then, we have to check and adjust the pressure valve.

7. the oil grade is low or the oil quality is poor. Screw air compressor should use special compressor oil. If other low-grade or inferior oil is used, the viscosity and specific heat will not reach the standard and the temperature will rise.

8. the effect of oil cut-off valve failure. The oil cut-off valve between the oil filter and the compressor, if the oil cut-off valve cannot be started, it will be cooled without oil lubrication. After the compressor is started, the temperature will continue to rise, and it will automatically stop in about one minute.

1. Remove the temperature plug at the head end of the air compressor. If the temperature plug is found to be dry and oil-free, there is still smoke floating out of the hole.

2. Check the manhole at the bottom of the air compressor, remove the oil cut-off valve, gently move the valve stem, and observe whether it can be pushed back and forth and reset easily. If not, the oil cut-off valve needs to be disassembled.

3. Check whether the valve stem or valve hole is oily, if there is, you need to polish it with fine sandpaper until it can slide easily;

4. Check whether the spring is broken or stuck with foreign objects. If so, it will affect the movement of the valve stem. Then, we need to replace the spring or clean the spring and spring seat.

The 9. thermostat bypass valve is in the open position. After the temperature bottom rises, it will gradually close. When it fails, it may always be in the open position, and the cooling oil will directly flow back to the air compressor, so the temperature will gradually rise and cause the shutdown.