At present, air compressors are basically designed with ultra-high temperature protection function. Once the exhaust temperature exceeds 100 °C, the temperature switch is instructed by the temperature sensor to act, an alarm is issued and an automatic shutdown is issued, and the exhaust temperature can be read on the instrument panel. The cooling measure of the machine itself is to spray lubricating oil into the compression chamber from the lower end and the left and right ends of the body, and after participating in the compression with the inhaled air, it is discharged from the bottom of the main engine to the oil and gas barrel. In addition to lubricating the screws, bearings, gears and other parts, it also produces a large amount of heat. However, when the heat has not been transferred, it needs to be cooled by the oil cooler before the next fuel injection action to completely cool down. Therefore, the occurrence of over-temperature faults is mostly related to the abnormality of the lubrication and cooling system.
For example: a certain type of air compressor has a high machine temperature. When the ambient temperature is 26°C, the exhaust temperature of the body is 88°C, and the soundproof cover is closed at 90°C, which obviously does not meet the full design input requirements of SA: the ambient temperature is below 35°C, the body outlet The temperature is 72-85°C. The ambient temperature is above 35°C, and the outlet temperature of the body is ambient temperature +50°C.
Consider and resolve the following points:
1. Whether the oil filter is blocked (observe whether the oil pressure gauge is normal)
2. The thermal control valve is blocked and does not work (use an infrared temperature sensor to measure the temperature of the pipeline before and after the thermal control valve)
3. Use an infrared temperature sensor to measure the temperature difference before and after the cooler (abnormalities are considered from both the fan and the cooler)
3.1. Use a multimeter to measure the fan current, use an anemometer to measure the speed of intake and exhaust, and use a tachometer to measure the fan speed;
3.2. Check whether the cooler is blocked; check whether there is a large gap between the cooler and its bracket;
4. Whether the air intake of the soundproof cover design meets the design input requirements
5. The above aspects are normal, and the fan with larger exhaust air volume can be replaced.
Attachment: How to exclude the fan not turning:
1. Check whether the wire ends are falling off;
2. Check whether the fan contactor is working normally;
3. Use a multimeter to check whether there is voltage, current, and resistance;
4. Switch between two phases at will
5. Replace the fan