[Mechanical Equipment Technology Edition] Daily Question 201801030: Common Faults in Refrigeration Systems (8.6)
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This post was last edited by YORK Industrial Refrigeration on 2018-2-1 at 09:28. Starting from now, in order to enhance communication among users, a \"Question of the Day\" activity has been launched on the Mechanical Equipment Technology forum. We hope everyone will participate actively to progress and improve together! ! ! Rewards: 3 wealth points for active participation, 10-15 wealth points for correct answers. This question is valid for two days; no score will be assigned after that period. What are the reasons for excessively high oil temperature in a refrigeration compressor? 1. How is the oil heated? 1.1 is because the oil carries away the heat from the compressor ； 1.2 There is a problem with the cooling effect of oil cooling. 2. Why is the compressor running at high temperature? 2.1 Insufficient refrigerant being drawn in (cause of low suction pressure) 2.2 Wear and tear on the compressor 2.3 External pressure ratio is higher than the internal pressure ratio 2.4 Fault in liquid injection cooling 2.5 Oil quality issues 3. Why is the oil cooling effect poor? . . . . . What is discussed here is mainly a approach to maintenance analysis ============================== High-quality promotions: Mobile equipment——York screw compressors: Maintenance procedures https://bbs.hcbbs.com/thread-1806833-1-1.html Mobile equipment——Upgrading York Quinton control centers https://bbs.hcbbs.com/thread-1804837-1-1.html Mobile equipment——Overhaul of GEA Grasso screw compressors https://bbs.hcbbs.com/thread-1800467-1-1.html Mobile equipment——Disassembly and maintenance of British HOWDEN screw compressors https://bbs.hcbbs.com/thread-1832529-1-1.html Mobile equipment——Disassembly and maintenance of Japanese Maekawa MYCOM screw compressors https://bbs.hcbbs.com/forum.php?mod=viewthread&tid=
1. Insufficient amount of refrigerant in the cooling system causes the compressor’s exhaust temperature to rise, as well as the return gas temperature; this reduces the cooling effect of the return gas, resulting in excessively high oil temperature. 2. An excess of refrigerant in the cooling system causes the compressor’s exhaust pressure to rise, as well as the exhaust temperature and oil temperature. 3. Poor insulation of the refrigeration system pipes. 4. The cooling efficiency of the refrigeration system’s cooler deteriorates. 5. The evaporation load on the evaporator of the refrigeration system increases.
The following reasons may lead to excessively high oil temperature: 1. Insufficient amount of refrigerant in the compression system of the low-pressure chamber, which results in an increase in the compressor’s exhaust temperature and return gas temperature; this reduces the cooling effect on the return gas, thereby causing the oil temperature to rise. 2. An excess of refrigerant in the high-pressure chamber compression mechanism refrigeration system leads to an increase in the compressor’s exhaust pressure, as well as an increase in the exhaust temperature and oil temperature. 3. Poor insulation of the refrigeration system pipes. 4. The cooling efficiency of the refrigeration system’s cooler has decreased. 5. The evaporation load on the evaporator of the refrigeration system increases.
1. In a low-pressure chamber compression refrigeration system, an insufficient amount of refrigerant leads to an increase in the compressor’s exhaust temperature as well as the return gas temperature; this reduces the cooling effect of the return gas, resulting in excessively high oil temperatures. 2. An excess of refrigerant in the high-pressure chamber compression mechanism refrigeration system leads to an increase in the compressor’s exhaust pressure, as well as an increase in the exhaust temperature and oil temperature. 3. Poor insulation of the refrigeration system pipes. 4. The cooling efficiency of the refrigeration system’s cooler has decreased. 5. The evaporation load on the evaporator of the refrigeration system increases.
1. In a low-pressure chamber compression refrigeration system, an insufficient amount of refrigerant leads to an increase in the compressor’s exhaust temperature as well as the return gas temperature; this reduces the cooling effect of the return gas, resulting in excessively high oil temperatures. 2. An excess of refrigerant in the high-pressure chamber compression mechanism refrigeration system leads to an increase in the compressor’s exhaust pressure, as well as an increase in the exhaust temperature and oil temperature. 3. Poor insulation of the refrigeration system pipes. 4. The cooling efficiency of the refrigeration system’s cooler has decreased. 5. The evaporation load on the evaporator of the refrigeration system increases.
1. In a low-pressure chamber compression refrigeration system, an insufficient amount of refrigerant leads to an increase in the compressor’s exhaust temperature as well as the return gas temperature; this reduces the cooling effect of the return gas, resulting in excessively high oil temperatures. 2. An excess of refrigerant in the high-pressure chamber compression mechanism refrigeration system leads to an increase in the compressor’s exhaust pressure, as well as an increase in the exhaust temperature and oil temperature. 3. Poor insulation of the refrigeration system pipes. 4. The cooling efficiency of the refrigeration system’s cooler has decreased. 5. The evaporation load on the evaporator of the refrigeration system increases.
Excessive compression ratio; poor heat transfer in the oil cooler; intake of overheated gas; insufficient fuel injection.
1. Insufficient amount of refrigerant in the cooling system causes the compressor’s exhaust temperature to rise, as well as the return gas temperature; this reduces the cooling effect of the return gas, resulting in excessively high oil temperature. 2. An excess of refrigerant in the cooling system causes the compressor’s exhaust pressure to rise, as well as the exhaust temperature and oil temperature. 3. Poor insulation of the refrigeration system pipes. 4. The cooling efficiency of the refrigeration system’s cooler deteriorates. 5. The evaporation load on the evaporator of the refrigeration system increases.
What are the reasons for excessively high oil temperature in a refrigeration compressor? Answer: 1. In a low-pressure chamber compression refrigeration system, an insufficient amount of refrigerant leads to an increase in the compressor’s exhaust temperature as well as the return gas temperature; this reduces the cooling effect of the return gas, resulting in excessively high oil temperatures. 2. An excess of refrigerant in the high-pressure chamber compression mechanism refrigeration system leads to an increase in the compressor’s exhaust pressure, as well as an increase in the exhaust temperature and oil temperature. 3. Poor insulation of the refrigeration system pipes. 4. The cooling efficiency of the refrigeration system’s cooler has decreased. 5. The evaporation load on the evaporator of the refrigeration system increases.
The oil circulation volume in a refrigeration unit should be high; therefore, a high oil temperature is likely to be caused by a fault in the rotating components. During operation, wear of these components can lead to an increase in temperature. Normally, the oil mixes with the refrigerant, so it’s also possible that a high discharge pressure is the cause, in which case it might be related to problems with the circulating water or the condenser, among other things