Maintenance of high temperature alarm screw air compressor in summer

 

Generally speaking, the high temperature of air compressor is one of the most common faults in the use of air compressor, especially for the mobile air compressor which works in outdoor construction, the probability of this problem is more serious in the hot summer. The high temperature of screw air compressor is caused by the following reasons:

 

 

1、 The high temperature of screw air compressor caused by high ambient temperature mainly affects the air compressor from two aspects. A: The higher the temperature is, the thinner the air is (as if the efficiency of the air compressor is low in the plateau area), which will reduce the working efficiency of the air compressor, make the air compressor stay in the loading state for more time, carry more load, cause more heat generated by the air compressor, and the air compressor will surely have a higher temperature. B: General air compressor design has a design operating environment temperature (30-40 ℃), under the design operating environment temperature, the general maximum temperature of the air compressor is close to the protection temperature of the air compressor, if the air compressor environment temperature is higher than the design operating environment temperature, the temperature of the air compressor will be increased, so that the air compressor in the end even exceeds the shutdown temperature of the air compressor, resulting in High temperature of air compressor.

 

 

2、 The air compressor system is short of oil. The oil level of oil and gas drum can be checked. After shutdown and pressure relief, when the lubricating oil is in static state, 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 shall not be lower than the low oil level mark L (or mix). If the oil volume is insufficient or the oil level cannot be observed, stop the engine immediately for refueling

 

 

3、 The oil stop valve (oil cut-off valve) is not working properly. The oil stop valve is generally a two position, two normally closed solenoid valve, which is opened when starting and closed when shutting down (Atlas Copco machine is a mechanical open valve) to prevent the oil in the oil and gas barrel from continuing to spray into the head when shutting down and ejecting from the air inlet. If the element is not opened when it is loaded, the main engine will heat up rapidly due to lack of oil, which will cause the screw assembly to burn.

 

 

4、 Oil filter problem a: if the oil filter is blocked and the bypass valve is not opened, the air compressor oil will not reach the head, and the main engine will be heated rapidly due to lack of oil. B: The oil filter is blocked and the flow becomes smaller. One case is that the air compressor is not completely heated due to the heat taken away, and the temperature of the air compressor rises slowly to form a high temperature. The other case is that the air compressor is high temperature after unloading, because the internal oil pressure of the air compressor is high when loading, and the oil of the air compressor can pass through, while the pressure of the air compressor oil is low after unloading, and the oil of the air compressor passes through the air compressor The oil filter is difficult, and the flow is too small, which causes high temperature of the air compressor.

 

 

5、 Thermal control valve (temperature control valve) fails to work. The thermal control valve is installed in front of the oil cooler to maintain the exhaust temperature of the head above the pressure dew point. Its working principle is that when the machine is just started up, because the oil temperature is low, the branch of the thermal control valve is opened, the main circuit is closed, and the lubricating oil is injected directly into the machine head without the cooler; when the temperature rises above 40 ℃, the thermal control valve is gradually closed, and the oil flows through the cooler and the branch at the same time; when the temperature rises above 80 ℃, the valve is completely closed, and the lubricating oil enters the machine head through the cooler to maximize the effect on the lubricating oil Cool down. If the thermal control valve fails, the lubricating oil may enter the machine head directly without cooler, so that the oil temperature cannot be reduced, resulting in over temperature. The main reasons for the failure are as follows: first, the elasticity coefficient of the two thermal springs on the valve core changes after fatigue, and they can not act normally with the change of temperature; second, the valve body is worn, the valve core is stuck or the action is not in place, and they can not be closed normally. It can be repaired or replaced according to the situation.

 

 

6： Check whether the fuel volume regulator is normal (for Fusheng and other units, there is a fuel volume regulating valve), and increase the fuel injection volume appropriately if necessary. The fuel injection quantity has been adjusted when the equipment leaves the factory, which should not be changed in general.

 

 

7、 The oil deteriorates after the service time. The fluidity is poor, and the heat exchange performance is decreased. The heat of the air compressor head can not be completely taken away, resulting in high temperature of the air compressor.

 

 

8、 Check whether the oil cooler works normally. For water-cooled models, the temperature difference between the inlet and outlet water pipes can be checked, which should be 5-8 ℃ under normal conditions. If the temperature is lower than 5 ℃, there may be scaling or blockage, which will affect the heat exchange efficiency of the cooler and cause poor heat dissipation. At this time, the heat exchanger can be removed and cleaned.

 

 

9、 Check whether the temperature of cooling water population is too high, whether the water pressure and flow are normal, and whether the ambient temperature is too high for air-cooled models. Generally, the inlet temperature of cooling water shall not exceed 35 ℃, and the water pressure shall not exceed 35 ℃ Zero point three One 0.5MPA The flow between shall not be less than 90% of the specified flow. The ambient temperature shall not be higher than 40 ℃. If the above requirements are not met, it can be solved by installing cooling tower, improving indoor ventilation, increasing the room space, etc. You can also check the cooling fan for proper operation. If there is any fault, it shall be repaired or replaced.

 

 

10、 The air-cooled unit mainly checks whether the difference between the inlet and outlet oil temperature is about 10 degrees. If it is less than this value, check whether the fins on the radiator surface are dirty. If it is dirty, clean air can be used to dust the surface of the radiator, and check whether the fins of the radiator are corroded. If it is severely corroded, it is necessary to consider replacing the radiator assembly and whether the internal pipes are dirty. If there is such a phenomenon, check whether the fins on the radiator surface are dirty The circulating pump can be used to clean the radiator with a certain amount of acid liquid medicine. Pay attention to the concentration of the liquid medicine and the circulating time, so as to prevent the radiator from penetrating the cavity due to the corrosion of the liquid medicine.

 

 

11、 The problem with the fan of the air cooler is that the fan doesn't turn, the fan is in reverse phase, only one fan is turned on, etc.

 

 

12、 There are problems with the exhaust duct installed by the customers of the air-cooled model. The price of the exhaust duct is too small,