The compressor has become “generic machinery” as motor technology has advanced, particularly in the coal chemical industry, machinery industry, and other industries.
From a technical standpoint, both incremental and absolute encoders can be used for distance measurement applications. Absolute encoders provide higher precision and performance, whereas incremental encoders appear to be more cost-effective and practical.
The safe operation of the entire air conditioner or refrigerator is determined by a properly functioning compressor. Burnout, oiler failure, low pressure, and gas shortages, for example, could occur during the operation of a piston compressor. When these issues arise, the appliance will not function properly.
The compressor’s operating rate and product production are affected by how soon and precisely these faults are detected and resolved.
This post will look at all of the common problems with AC compressors and offer remedies.
A possible issue from the standpoint of airflow is that the wind pressure or compressed air temperature is too high, which could result in spontaneous combustion of carbon deposits and explosion of the pressure vessel if the protective device fails.
Another issue could be that the air volume is insufficient or too low, which would have an impact on production.
There are four sorts of faults in the compressor structure: lubrication system issues, cooling water circuit issues, compressed air circuit issues, and mechanical failure.
Burnout of the Compressor Shell
The Babbitt layer of the main bearing shell or connecting rod bearing shell may be burned or fall off when a piston compressor is in use. The temperature of the bearing shell rises as a result, resulting in high temperatures and smoke, melting the Babbitt alloy.
Low Oil Temperature -1.1
Previously, we were concerned about the high oil temperature in the crankcase, which could lead to burnout. The manual specifies that the oil temperature must not exceed 60°C or 70°C, however there is no minimum temperature.
Oil temperatures that are lower than the industry standard, on the other hand, may cause the same problem. The oil temperature in the compressor’s crankcase is decreased in the winter after the compressor is turned off. As a result, the oil is excessively viscous, and the shell is burned when the machine is restarted. As a result, in the winter, it is preferable to use low-consistency oil.
-1.2 Crankcase Oil Level Is Low
The lowering oil level cannot be found if the lower hole of the oil level is plugged. The oil pump will also suck in air occasionally if the crankcase oil level is too low.
The drainpipe generates air drag, which damages the bearing shell’s oil film. After then, the compressor shell would become increasingly dry, eventually leading to burnout.
-1.3 Between Bearing Shell and Shaft Clearance
To test the clearance between the bearing shell and the shaft, we used to utilize the method of pressing lead wire.
Because the main bearing is fixed and the upper shell cover is buckled on the main journal, which will not move when the bolt is tightened, this method is suited for measuring the main bearing shell.
The method, however, is ineffective for measuring the connecting rod bearing shell. The lead wire will be pinched as the connecting rod is tightened. The clearance cannot be accurately reflected if the connecting rod is slanted.
As a result, we should utilize a dial indication to determine the clearance based on the shaft size.
Failure of the Oil Injector -2.1 Failure to Fill Oil
The oil injector should be disassembled and inspected if it is not filled with oil.
You should clean, repair, and replace the plunger and pump body if they are extremely worn, causing the gap to widen and the pressure oil to flow back.
-2.2 Oil Sucking Failure
If the oil injector does not suction oil and does not drop oil when observed through the oil cover, this indicates that the oil suction valve is jammed or that the oil cover is not properly placed, allowing air to enter.
The oil suction ball valve in the oil injection pump must be cleaned, and the oil cover’s rubber ring must be replaced.
-2.3 Inadequate Oil Supply
The oil injector’s low oil supply is the result of long-term operation with an unclean system, which eventually led to pipeline blockage. It’s also possible that the nut joint was not properly tightened following the maintenance, resulting in oil leaks. Clean the pipeline and tighten the joints to address the problem.
Insufficient air volume and low pressure
When the compressor pressure is low and the air volume is insufficient, and there is no air leakage in the compressed air pipeline, the compressor unit is typically the problem.
The compressor unit’s exhaust volume is insufficient due to a variety of issues.
-3.1 Consistent Upkeep
First, see if the compressor discharge has decreased following maintenance. How long has the service been going on? Check whether the air filter is blocked after the compressor has ran for 2000 hours if the environment is not optimum.
If the air filter is not severely clogged, a simple dust removal operation will suffice. You should replace the old air filter with a new one if the obstruction is severe.
When the compressor discharge drops, there is usually no significant problem. The issue is that the consumer fails to maintain the compressor, resulting in a clogged air filter. The compressor can resume regular operation after a replacement air filter is installed.
Lubricant and other filter elements, in addition to an air filter, are essential. Check to see if the lubricant falls within the recommended range. If it’s missing, please fill in the blanks.
-3.2 Intake Valve Open
Check the unit if the compressor’s discharge drops.
If your compressor has just undergone maintenance and all three filters and oil products are in good working order, a technician should inspect the compressor’s intake valve.
Remove the intake hose, turn on the compressor, and check to see if the intake valve is opening normally.
In general, the intake valve’s theoretical design service life is 100000 times. The quality may change due to each manufacturer’s varied brands and batches. As a result, if the intake valve fails, the exhaust volume of the unit may be reduced.
If the intake valve cannot fully open when the compressor is loaded, the drop in exhaust volume is likely due to a problem with the intake valve, which should be removed for maintenance or replacement.
-3.3 Failure of the Motor
If the exhaust volume of the unit remains unchanged after troubleshooting the intake valve, you should check whether the engine is working properly.
The motor speed is lower than the rated speed due to a local short circuit in the motor coil, bearing wear, and motor shaft wear, reducing the compressor’s discharge capacity. After the motor coil and bearing have been serviced, the compressor’s discharge capacity should be verified.
The working pressure is set at -3.4.
If the compressor’s working pressure switch is set lower than standard, it should be raised to a higher value.
The working pressure of the compressor is set according to client requirements during factory debugging. It may be set at a differential pressure during the customers’ use period. When the compressor starts pumping air into the air tank and the pressure hits 10kg, for example, the compressor stops or unloads. The compressor restarts when the pressure hits 7kg. There is a difference in pressure between them. This procedure may cause the compressor to take a break in order to safeguard it.
Compressor switches can be adjusted in a variety of ways. One is that the pressure difference is set by the switch, which only controls the automated shutdown and maximum pressures. This switch has two buttons that may be changed using a slotted screwdriver. The two buttons must be set in a similar manner. Otherwise, they will move in lockstep, stopping, starting, and stopping again, eventually burning out the electrical equipment.
The other is to regulate the starting (low) and stopping (high) pressures (high pressure).
Adjusting the Compressor Pressure
To increase the closing and opening pressures at the same time, turn the pressure adjusting screw clockwise. Reduce the closing and opening pressures at the same time by turning the pressure regulating screw anticlockwise.
Compressor Pressure Differential Adjustment
The closing pressure does not change when the differential pressure adjusting screw is moved clockwise, while the opening pressure increases. The closing pressure remains unchanged when the differential pressure adjusting screw is moved anticlockwise, but the opening pressure drops.
If the working pressure error is caused by a pressure switch failure, you should replace the pressure switch if it cannot be rectified.
-3.5 Environmental Change
If a compressor was initially operated in a low altitude area and then moved to a high altitude area with other equipment owing to a manufacturing relocation, the climate became humid, which could result in a reduction in unit discharge.
The thinner the air is at higher altitudes, the less gas is produced per unit time. If there is too much water in the air, compressed air will naturally include a large amount of water. The presence of water vapour in the subsequent processes will result in less exhaust.
-3.6 Compressor Drive Loose Belt
You should adjust the drive belt in this scenario. Replace it with a new one if it is damaged.
The right positioning strategy should be chosen based on the match between the pulley and the shaft.
A compressor motor and a pulley are mounted on the compressor head shaft. To begin, the compressor head pulley is fastened and locked.
You can tighten it if it’s loose.