The cold room piston refrigeration compressor relies on the reciprocating motion of the piston to compress the gas in the cylinder. Usually, the rotary motion of the prime mover is converted into the reciprocating motion of the piston through the crank-link mechanism. The work done by the crankshaft every revolution can be divided into the suction process and the compression and exhaust process.
In the daily use of piston refrigeration compressors, 12 common faults and their troubleshooting methods are sorted out as follows:
1) The compressor consumes a lot of oil
Reason: The gap between the bearing, oil ring, cylinder and piston is too large, which increases the fuel consumption.
Remedy: Carry out corresponding maintenance or replace parts.
2) Bearing temperature is too high
Reasons: Dirty oil, blocked oil passage; insufficient oil supply; too small clearance; eccentric wear of the bearing or roughening of the bearing bush.
Elimination: Clean the oil circuit, change the lubricating oil; provide sufficient oil; adjust the clearance; overhaul the bearing bush.
3) The energy regulation mechanism fails
Reason: The oil pressure is not enough; the oil contains refrigerant liquid; the oil outlet valve of the regulating mechanism is dirty and blocked.
Elimination: Find out the reason for the low oil pressure and adjust the oil pressure; warm up the oil in the crankcase for a longer time; clean the oil circuit and oil valve to make the oil circuit unblocked.
4) Exhaust temperature is too high
Reasons: large load; too large clearance volume; damaged exhaust valve and gasket; large suction superheat; poor cylinder cooling.
Elimination: reduce the load; adjust the clearance with the cylinder gasket; replace the threshold plate or gasket after inspection; increase the amount of liquid; increase the amount of cooling water.
5) Exhaust temperature is too low
Reasons: the compressor sucks liquid; the expansion valve supplies too much liquid; the cooling load is insufficient; the evaporator frost is too thick.
Elimination: reduce the opening of the suction valve; adjust the liquid supply to make the superheat of the return air between 5 and 10; adjust the load; regularly sweep or flush the frost.
6) The exhaust pressure is too high
Reason: The main problem is the condenser, such as non-condensable gas in the system; the water valve δ is open or the opening is not large, the water pressure is too low to cause insufficient water or the water temperature is too high; the air-cooled condenser fan δ is open or the air volume Insufficient; Too much refrigerant charge (when there is no liquid receiver); Too much dirt in the condenser; The compressor exhaust valve δ is opened to the maximum} The exhaust pipe is not smooth.
Elimination: deflate at the high-pressure exhaust end; open the water valve to increase the water pressure; turn on the fan to reduce wind resistance; remove excess refrigerant; clean the condenser and pay attention to the water quality; open the exhaust valve; clear the exhaust pipe.
7) Exhaust pressure is too low
Reasons: Insufficient refrigerant or leakage; air leakage from the exhaust valve; excessive cooling water volume, low water temperature, and improper energy regulation.
Elimination: leak detection and elimination of leaks, replenishment of refrigerant; repair or replacement of valve slices; reduction of cooling water; repair of energy regulating devices
8) Wet compression (liquid hammer)
Reasons: The liquid level of the evaporator is too high; the load is too large; the suction valve is opened too fast.
Elimination: adjust the liquid supply valve; adjust the load (adjust the energy adjustment device); the suction valve should be opened slowly, and should be closed if there is liquid hammer.
9) Oil pressure is too high
Reason: Improper adjustment of oil pressure; poor oil pipe; inaccurate oil pressure gauge.
Remedy: readjust the oil pressure valve (relax the spring); check and clean the oil pipe; replace the pressure gauge
10) The oil pressure is too low
Causes: Insufficient oil quantity; improper adjustment; clogged oil filter or clogged oil inlet; worn oil pump; (evaporator) vacuum operation.
Remedy: add oil; adjust the oil pressure regulating valve} remove and clean, remove the blockage; repair the oil pump; adjust the operation to make the crankcase pressure higher than the atmospheric pressure.
11) The oil temperature is too high
Reasons: exhaust temperature is too high; oil cooling is not good; assembly clearance is too small.
Elimination: Solve the cause of high exhaust pressure; increase the amount of cooling water; adjust the clearance.
12) Motor overheating
Reasons: low voltage, resulting in large current; poor lubrication; overload operation; non-condensable gas in the system; damage to the insulation of the electric winding.
Elimination: check the cause of low voltage and eliminate it; check the lubrication system and solve it; reduce load operation; discharge non-condensable gas; check or replace the motor.
Post time: Mar-24-2023