1 working principle
The working principle of TSA-230A screw air compressor consists of four processes: suction, sealing and conveying, compression and fuel injection and exhaust. When the rotor rotates, the groove of the main and auxiliary rotors is turned to the opening of the intake end wall. At this time, the space is the largest, and the groove space of the rotor is open to the air inlet. When the rotor is turned to the intake port, the outside air is sucked into the main and auxiliary rotors in the axial direction. When the air fills the entire tooth groove, the intake side end face is turned away from the casing air inlet, and the air between the tooth grooves is closed.
As the primary and secondary rotors rotate, air in the gullies is delivered to the exhaust end. During the conveying process, the engaging surface gradually moves toward the exhaust end, the gas is gradually compressed, and the pressure is also increased, and the lubricating oil is injected into the compression chamber to mix with the air under the pressure difference. When the rotor is turned to the exhaust port, the compressed gas is exhausted, and as the rotor continues to rotate, it enters the next gettering process.
2 common fault analysis and processing methods
The Fuzhou Locomotive Depot began loading TSA-230A screw air compressors in 2002. According to the application in recent years, there are two main types of screw air compressor failures: abnormal sound and leakage.
2.1 compressor abnormal sound
There are many reasons for the abnormal sound of the screw air compressor during operation. We have summarized and analyzed some common faults and treatment methods.
2.1.1 Screw group wear
Fault analysis: When the compressor screw rotates, the lubricating oil and the compressed air rub against the screw, so that the working surface of the screw gradually wears out, and the diameter of the hole in the machine gradually increases, causing the flow of gas and lubricating oil from the diameter gap to the intake direction to increase. The amount of gas discharged is reduced.
Treatment method: The screw group wears a lot, and if the locomotive section cannot handle it, it will be sent to the factory for repair.
2.1.2 Bearing defect or wear
Failure analysis:
(1) When the bearing is used for a period of time, the inner ring of the bearing, the rolling element, the cage, the outer ring, the raceway, etc. produce certain defects and scars, resulting in excessive bearing wear, causing turbulence and abnormal sound during operation. In addition, the lack of oil and excessive oiling of the bearings are also prone to failure. If the oil is added less, the bearing lubrication will be poor and the heat will be generated. If it is added, it will easily cause the stirring to overheat.
(2) The bearing is used for too long, which exceeds the service life of the bearing and is prone to fatigue of the material. The strong impact of the material causes the material to deform, causing the roller and the raceway surface to peel off and crush, resulting in poor lubrication. And the vibration is increased.
Treatment method: (1) It is necessary to supply oil in maintenance and ensure the cleanness of grease. The proper amount of oil for the bearing can ensure the bearing has good lubrication and establish normal clearance and necessary oil film. (2) Fix the non-bearing end of the screw set to enhance the stability of the bearing operation. (3) Send the factory to repair or replace the bearing.
2.1.3 oil-water ratio water content is large
Fault analysis: The compressor continuously meets the condensed water in the air during operation and is stirred vigorously, which is easy to produce emulsification, resulting in unclear oil and gas separation and increased fuel consumption. As the oil is emulsified, the oil film is destroyed, causing abrasion and abnormal sound.
Treatment methods: (1) Strengthen maintenance and regularly drain the oil cylinders. (2) Install a thermostatic sleeve on the oil cylinder to reduce the formation of moisture.
2.1.4 Damage to the cushion
Fault analysis: The cushion is aging and damaged, causing the screw to be agitated and producing abnormal sound.
Treatment: Strengthen daily maintenance, replace cushions in time, and use a stable cushion.
2.1.5 Centrifugal fan off
Fault analysis: the screw of the air compressor base and other parts are loose or the parts are off, which also makes the air compressor run very noisy. The more common is that the centrifugal fan is easily damaged due to the soft material or the defects of the manufacturing process. Falling off, causing abnormal sound when the air compressor is running.
Treatment method: replace the centrifugal fan, change the aluminum to an iron centrifugal fan, and use the open type on the edge.
2.2 compressor oil leakage
After using the compressor for a period of time, it is often found that there are oil stains on the body or around it, indicating oil leakage.
2.2.1 oil filter crack
Fault analysis: (1) The inside of the oil filter is too dirty, which will cause the oil filter to be clogged, the passing ability is reduced, the outlet pressure is low, the energy consumption is increased, and even the oil filter leaks. (2) Long-term accumulation of water at the bottom of the oil filter will also crack the oil filter. Because the moisture in the air enters the circulation system with the compressor, because the specific gravity of the water is heavier than the oil, the water is deposited at the bottom of the oil filter, and the oil filter is rusted, causing the oil filter to leak oil.
Treatment method: (1) Modify the layout of the oil filter, and change the bottom of the oil filter to face upward to avoid water rust. (2) Strengthen daily inspection and maintenance, and regularly change the oil filter.
2.2.2 Radiator crack
Fault analysis: If the radiator is not welded firmly or the body has shrinkage holes, the oil and air oil mixture will also leak from the radiator.
Treatment method: replace the new product. It is recommended to increase the test pressure when the radiator is shipped from the factory to ensure operational reliability.
2.2.3 Air filter leakage
Fault analysis: The air filter is not cleaned in time, the filtration efficiency is reduced, the air circulation resistance is increased, the intake air amount is reduced, causing serious wear of the cylinder, piston and other parts, and leakage or sticking of the intake check valve. The pressure pipe enters the intake area and the like, causing the air filter to leak oil.
Treatment method: Check the air compressor filter. If there is any damage, defective or dirty air filter, replace it in time; check the intake valve and replace if damaged.
2.2.4 Oil and gas cylinder head oil leakage (screw shaft seal)
Fault analysis: The oil seal of the oil and gas cylinder head is poor or the support of the screw group is worn, causing oil leakage in the cylinder head of the oil and gas cylinder.
Treatment method: Because the station section is not filled with oil seals into the equipment, it is sent to the factory for repair.
2.2.5 Pressure switch oil leakage
Fault analysis: (1) Poor seal of the oil switch under the oil switch of the pressure switch also causes the pressure switch to leak oil. (2) Poor connector.
Treatment method: (1) Replace the pressure switch. (2) Repair the pipe joint (horn).
3 Conclusion
In the years after the use of the screw air compressor in the Fuzhou Locomotive Depot, the air compressor replaced 23 compressors due to compressor noise, and 14 radiators were replaced by oil leakage. The centrifugal fan was removed and replaced. There were 16 units in the oil filter that were leaking oil, and 50 cushions were replaced by the cushion. Therefore, the above methods of analyzing and handling faults were awarded to the in-service adult college students, and they emphasized daily maintenance and maintenance, timely found and handled compressor failures, and ensured the safe operation of the locomotive.
Double head embroidery machine
Double Head Computer Embroidery Machine,Computer Embroidery Machine Double Head,Industrial Sewing And Embroidery Machine,Industrial Digital Embroidery Machine
Ningbo World Wide Electric techonology CO.,Ltd , https://www.ningbomachine.com