The working principle of the screw air compressor: The compressed air system employs a double-screw air compressor. The operation of this machine consists of three processes: intake, compression, and exhaust.
(1) Inhalation process:
The motor drives the rotor. When the red recessed spaces of the main rotor and the slave rotor face the opening at the intake end wall, the space expands and external air fills it. When the rotor end face on the intake side moves away from the shell's inlet, the teeth become teeth. The air between the recesses is trapped between the main rotor, the slave rotor and the shell, completing the suction process. When the gas fills the entire recess, the end of the rotor inlet side moves away from the shell inlet, and the gas in the recess is sealed.

(2) Compression process:
At the end of inhalation, the peak of the main rotor and the peak of the driven rotor are closed to the housing. At this point, the gas does not flow out of the slot and the tooth surface gradually moves towards the exhaust end. The space between the tooth surface and the exhaust port gradually decreases, and the gas in the groove increases with the increase in compression pressure.

(3) Exhaust process: When the toothed end face of the rotor is connected to the exhaust port of the housing, the compressed gas begins to be discharged until the tooth tip of the tooth surface and the groove reach the exhaust end face. At this point, the tooth surfaces of the main rotor and the auxiliary rotor are discharged from the housing. The space of the end cover plate is zero, indicating that the exhaust process is complete. At the same time, the gap length between the rotor tooth surface and the air inlet of the housing is the longest, and the intake process is repeated.

Due to the excessively high temperature of the screw air compressor, the typical causes for shutdown are as follows:

The environmental ventilation and heat dissipation are insufficient. There are three main situations: the surrounding environment of the screw air compressor affects heat dissipation; one is that it is too close to a wall obstruction; the other is another heat source near the screw air compressor. The third is that the front and side doors of the screw air compressor are opened during operation, generating strong air currents.

2. The blades of the screw pneumatic electric fan are cracked or drooping. If the blades are broken, the air compressor will operate for 5 minutes, the temperature will rise, and it will automatically stop. If an abnormal sound is heard, the cooling of the blades will be reduced, resulting in a decrease in the cooling air volume and affecting heat dissipation. At this time, the fan blades need to be replaced or adjusted.
3. The oil filter of the screw air compressor is too dirty. When the dirt is severe, the dirty oil cannot flow into the air compressor at the normal rate, and due to the lack of cooling oil, the air compressor will operate abnormally. If the hydraulic difference between the inlet and the outlet exceeds 0.18 MPa, the filter element must be replaced.

4. The coolant oil level is too low. When observing the refrigeration unit, if the oil level drops below the bottom of the test tube, it should be corrected immediately. The correction must be made to the position directly below the center of the oil seal you are dealing with.

5. The amount of cooling oil is very small or the quality of the oil is poor. The screw air compressor uses the special air compressor oil provided by the manufacturer, but it uses other inferior or contaminated oil instead. The viscosity and specific heat do not meet the specifications, and the temperature is also too high.

6. Radiator blockage. If there is a large amount of dust around the screw air compressor, a layer of dust and sludge will form adhering to the surface of the radiator during long-term operation. The internal copper tubes are also simply blocked by the accumulation of lubricating grease, which will affect heat dissipation. The air cooler should be cleaned with a dust blower. However, if it is not cleaned, it should be removed, cleaned with a high-pressure water gun, and cleaned with a special chemical solution. For the water cooler, a water pump is used to recover the chemical solution.

7. The oil cut-off valve of the screw air compressor will be damaged. There is a fuel cut-off valve between the oil filter and the air compressor. If the oil cut-off valve cannot be opened, due to the lack of oil lubrication and cooling, the temperature of the screw air compressor will rise rapidly after startup and automatically stop within a few seconds.

8. The filter element of the oil-gas separator is too dirty. When it becomes too dirty, the oil will encounter excessive resistance during circulation, causing overheating and resulting in a shutdown. In such cases, the filter element should be cleaned or replaced.

For more information about screw air compressors, please visit our company, Hunan Ruiseng Mechanical Equipment Co., Ltd. We have Zhigao screw air compressors.