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1. Too high ambient temperature will cause high temperature to the screw air compressor. This mainly affects the air compressor from two aspects.
A: The higher the temperature, the thinner the air (as if the efficiency of the air compressor is low in the plateau area), resulting in a decrease in the efficiency of the air compressor, so that the air compressor is in the loading state for more time, with more load, resulting in air The heat generated by the compressor is more, and the air compressor must have a higher temperature.
B: When the general air compressor is designed, there is a design operating ambient temperature (30-40 degrees). When the air compressor is operated at the design operating ambient temperature, the maximum temperature is generally close to the protection temperature of the air compressor. If the air compressor environment If the temperature is higher than the designed operating ambient temperature, the temperature of the air compressor will increase, so that the air compressor will even exceed the shutdown temperature of the air compressor, resulting in high temperature of the air compressor.
2. The air compressor system is short of oil.
The oil level of the oil and gas barrel can be checked. After the pressure is stopped and the lubricating oil is static, the oil level should be slightly higher than the high oil level mark H (or MAX). During the operation of the equipment, the oil level cannot be lower than the low oil level mark L (or MIX). If it is found that the amount of oil is insufficient or the oil level is not observed, stop and refuel immediately.
3. The oil stop valve (oil stop valve) is not working properly.
The oil stop valve is usually a two-position two-position normally closed solenoid valve, which is opened at start and closed at stop to prevent the oil in the oil and gas barrel from continuing to be sprayed into the machine head during the stop and sprayed from the air inlet. If the component does not turn on when it is loaded, the main unit will quickly heat up due to lack of oil, and in severe cases, the screw assembly will burn.
4. The oil filter problem.
A: Blocking the bypass valve without opening the oil filter will cause the air compressor oil to fail to reach the head, and the main unit will quickly heat up due to lack of oil.
B: The flow rate of the oil filter becomes smaller. In one case, the temperature of the air compressor is not very complete because the heat is not taken away. The temperature of the air compressor gradually rises to form a high temperature. The other situation is that the air compressor is high after unloading. , Because the internal oil pressure is high when the air compressor is loaded, the air compressor oil can pass through, and the air compressor oil pressure is low after the air compressor is unloaded. It is difficult for the air compressor oil to pass through the air compressor oil filter, and the flow rate is too small to cause air Press high temperature.
5. The thermal control valve (temperature control valve) fails to work.
The thermal control valve is installed in front of the oil cooler, and its function is to maintain the temperature of the head exhaust gas above the pressure dew point. The working principle is that when the oil temperature is low at the start-up, the thermal control valve branch is opened, the main circuit is closed, and the lubricating oil is directly injected into the machine head without the cooler; when the temperature rises above 40 ℃, the thermal control valve is gradually closed The oil flows through the cooler and the branch at the same time; when it rises above 80 ° C, the valve is completely closed, and the lubricating oil enters the machine head through the cooler to cool the lubricating oil to the greatest extent.
If the thermal control valve fails, the lubricating oil may directly enter the machine head without the cooler, so that the oil temperature cannot be lowered, resulting in over-temperature. The main reason for its failure is that, first, the size of the spool and the two thermal springs change their elastic coefficients after fatigue, and cannot operate normally with temperature changes; second, the valve body is worn, the spool is stuck or the action is not in place, and it cannot be closed . Can be repaired or replaced according to the situation.
6. Check whether the oil quantity regulator is normal, and increase the fuel injection quantity if necessary.
The fuel injection quantity has been adjusted when the equipment leaves the factory and should not be changed under normal circumstances.
7. If the oil exceeds the usage time, the oil will deteriorate.
The fluidity of the engine oil deteriorates, and the heat exchange performance decreases. The heat of the air compressor head cannot be completely taken away, resulting in high temperature of the air compressor.
8. Check whether the oil cooler is working properly.
For water-cooled models, the temperature difference between the inlet and outlet pipes can be checked. Normally, it should be 5-8 ° C. Below 5 ° C, there may be scaling or blockage, which will affect the heat exchange efficiency of the cooler and cause heat dissipation. Bad, at this time, the heat exchanger can be removed and cleaned.
9. Check whether the temperature of the cooling water inlet is too high, and whether the water pressure and flow rate are normal. For air-cooled models, check whether the ambient temperature is too high.
The inlet temperature of the cooling water should generally not exceed 35 ° C, and the flow rate of the water pressure between 0.3 and 0.5 MPA should not be less than 90% of the specified flow rate. The ambient temperature should not be higher than 40 ℃. If the above requirements are not met, it can be solved by installing cooling towers, improving indoor ventilation, and increasing the space of the equipment room. You can also check whether the cooling fan is working properly. If there is a malfunction, it should be repaired or replaced.
10. The air-cooled unit mainly checks whether the temperature difference between the incoming and outgoing oils is about 10 degrees. If it is less than this value, it should be checked whether the fins on the surface of the radiator are dirty or clogged. Whether the sheet is corroded, if it is severely corroded, it is necessary to consider replacing the radiator assembly, whether there is a dirty blockage in the internal pipeline, if there is this phenomenon, it can be cleaned by a circulating pump with a certain acidic liquid, and the concentration of the liquid and the cycle time Avoid the radiator from passing through the cavity due to the corrosion of the medicine.
11. The fan problem of the air-cooled machine is that the fan does not rotate, the fan is reversed, and only two fans are turned on.
12. Problems with the exhaust duct installed by customers of air-cooled models.
Exhaust ducts have too small airflow surface, too long exhaust ducts, too many middle ducts of exhaust ducts, too many middle ducts of exhaust ducts, whether there is an exhaust fan installed, the exhaust fan flow is less than the original cooling fan of the air compressor .
13. The temperature sensor reading is inaccurate.
14. The computer reading is not accurate.
15. Head problems.
This general air compressor head bearing needs to be replaced in 20000-24000 hours, because the gap and balance of the air compressor are located by the bearing. If the wear of the bearing increases, it will cause the air compressor head to generate more heat , Causing high temperature of the air compressor.
16. Incorrect lubricating oil specifications or poor quality.
The lubricating oil of the screw machine generally has strict requirements and cannot be substituted at will. The requirements in the instruction manual of the equipment shall prevail.
17. Check if the air filter is blocked.
A clogged air filter will cause the load of the air compressor to be too large, and it will cause high temperature if it is under loading for a long time. It can be checked or replaced according to the alarm signal of the differential pressure switch. Generally, the first problem caused by air filter clogging is the reduction of gas production, and the high temperature of the air compressor is a secondary performance.
18. Check if the pressure is too high.
The system pressure is generally adjusted at the factory. If it is necessary to adjust, the rated gas pressure marked on the equipment nameplate shall prevail. If the adjustment is too high, overheating will occur due to the increased load of the machine. This is also the same as the previous reason. The high temperature of the air compressor is a secondary performance. The main performance is that the motor current of the air compressor rises and the air compressor protection stops.
19. The oil and gas separator is clogged.
The blockage of the oil and gas separator will cause the internal pressure to be too high, which will cause many problems. High temperature is one of them. This is also the same as the first two reasons. The clogging of the oil and gas separator is mainly manifested by high internal pressure.
