Knowledge

Air compressor common fault (two)



Six, what factors will affect the actual displacement of the screw compressor

The theoretical displacement of a screw compressor depends on the interdental volume, the number of teeth and the speed of rotation. The interdental volume is determined by the geometry of the rotor. For compressors, the actual exhaust volume is less than the theoretical exhaust volume possible for:

1) leakage; between rotors and between the rotor and the shell is not in operation during operation, to maintain a certain gap, it will have a gas leak, the gas after the pressure rise through the gap to the suction tube and is inhaling Of the gullet leakage, will make the exhaust volume reduced. In order to reduce the amount of leakage, there is a sealing tooth on the tooth top of the driven rotor, and the sealing ring groove is formed on the tooth root of the active rotor, and annular or strip-shaped sealing teeth are also processed on the end surface. If these seals wear, will increase the amount of leakage, displacement will be reduced.

2) breathing state; screw compressor is a positive displacement compressor, suction volume unchanged, when the suction temperature increases, or the intake pipe resistance is too large to reduce the suction pressure, the gas density decreases, The corresponding will reduce the quality of the gas displacement.

3) cooling effect; the temperature of the gas in the compression process will increase, the rotor and the temperature can be increased accordingly, so the process of inhalation, the gas will be heated by the rotor and can be expanded, so the corresponding reduction in suction Gas volume. Some of the screw-type air compressor rotors use oil cooling, the case water cooling, one of the purposes is to reduce its temperature. When the cooling effect is not good, the temperature is increased, the displacement will be reduced.

4) Speed; Screw compressor displacement and speed is proportional to, and speed will often with the grid voltage and frequency changes, when the voltage decreases or the frequency decreases, the speed will decrease, so that gas reduction.

Seven, the main reason for the screw compressor temperature is too high

1) bearing clearance is small

2) bearing pad is damaged

3) Lube oil supply pressure is too low

4) poor compressor oil return

5) the compressor is in abnormal working condition, axial thrust is too large (thrust bearing)

6) Lube oil heat exchanger efficiency is reduced, into the oil temperature is high

7) If the above reasons do not exist, the temperature measurement platinum resistance is connected to determine the normal temperature will be displayed on the bearing.

Eight, air compressors do not load the reasons and solutions

1) Reason: gas pipeline, the pressure exceeds the rated load pressure, the pressure regulator disconnected

Solution: No measures to be taken, pressure on the gas line When the regulator regulates the air pressure, the air compressor will automatically load

2) Cause: The solenoid valve has failed

Solution: remove the inspection, if necessary, replace

3) Cause: there is leakage on the control line between the oil-gas separator and the unloading valve

Solution: check the pipeline and connections, if leaks need to be repaired

Nine, air compressor noise suddenly increased

1) Inlet end bearing damaged

2) The exhaust end bearing is damaged

3) motor bearing damage

During operation, no condensate is discharged

1) Exhaust pipe is clogged

2) automatic trap

After the relief valve is released immediately, the safety valve failure,

Ten, air compressor is operating normally, stop after starting difficult

1) the use of oil grades wrong, or the use of a mixture of oil 2) sticky oil, coking 3) seal leak serious 4) unloading valve flap the original position changes