How to find the root cause of lubricant deterioration?
author: Leila
2024-07-23
There are many reasons for lubricant deterioration, the most common ones are lubricant oxidation, high temperature deterioration, pressure, additive depletion and lubricant contamination.
Lubricant oxidation (oxidation)
Lubricant oxidation is the reaction between oil molecules and oxygen molecules. Oxidation will cause the viscosity of lubricants to increase, and form varnish, sludge and precipitation. Oxidation will also accelerate the depletion of additives and cause base oil decomposition. Once the lubricant begins to oxidize, the acid value will begin to increase. In addition, oxidation will cause equipment to rust and corrode.
Lubricant oxidation (oxidation)
Lubricant oxidation is the reaction between oil molecules and oxygen molecules. Oxidation will cause the viscosity of lubricants to increase, and form varnish, sludge and precipitation. Oxidation will also accelerate the depletion of additives and cause base oil decomposition. Once the lubricant begins to oxidize, the acid value will begin to increase. In addition, oxidation will cause equipment to rust and corrode.
High temperature
When using lubricants, pay special attention to avoid high temperatures. High temperatures are one of the main causes of lubricant deterioration. In addition to playing the role of lubricating and protecting equipment, lubricants also cool equipment components. High temperature operation will accelerate the loss of additives and base oils. Generally, the working temperature of lubricants is 30-80℃. The life of lubricants is closely related to their working temperature. Experience tells us that when the working oil temperature exceeds 60℃, the service life of the oil will be halved for every 18 degrees Fahrenheit (7.8 degrees Celsius) increase. Therefore, in the process of using lubricating oil, controlling the temperature of lubricating oil as much as possible helps prevent lubricating oil from deteriorating, such as using a heat exchanger to control the oil temperature.
When using lubricants, pay special attention to avoid high temperatures. High temperatures are one of the main causes of lubricant deterioration. In addition to playing the role of lubricating and protecting equipment, lubricants also cool equipment components. High temperature operation will accelerate the loss of additives and base oils. Generally, the working temperature of lubricants is 30-80℃. The life of lubricants is closely related to their working temperature. Experience tells us that when the working oil temperature exceeds 60℃, the service life of the oil will be halved for every 18 degrees Fahrenheit (7.8 degrees Celsius) increase. Therefore, in the process of using lubricating oil, controlling the temperature of lubricating oil as much as possible helps prevent lubricating oil from deteriorating, such as using a heat exchanger to control the oil temperature.
Bubbles + pressure (micro-dieseling)
Oil problems caused by bubbles are very common in hydraulic systems. When bubbles in lubricating oil reach high-pressure areas from low-pressure areas, the bubbles in the oil are compressed, which will cause the oil temperature around the bubbles to rise and cause oil oxidation. Therefore, high-quality lubricating oil should have good anti-foaming properties. In addition, air inhalation should be avoided during use.
Oil problems caused by bubbles are very common in hydraulic systems. When bubbles in lubricating oil reach high-pressure areas from low-pressure areas, the bubbles in the oil are compressed, which will cause the oil temperature around the bubbles to rise and cause oil oxidation. Therefore, high-quality lubricating oil should have good anti-foaming properties. In addition, air inhalation should be avoided during use.
Additive depletion
Most additives are consumed during use. It is of great significance to monitor the status of additives through oil testing. By monitoring additives, we can know whether the oil is "healthy". At the same time, oil testing can also tell us the reason for the depletion of additives.
Most additives are consumed during use. It is of great significance to monitor the status of additives through oil testing. By monitoring additives, we can know whether the oil is "healthy". At the same time, oil testing can also tell us the reason for the depletion of additives.
Lubricating oil is contaminated
Lubricating oil should be avoided from contamination during use, including water, dust, air, various impurities, other lubricating oils, etc. Various metal materials in certain metal equipment, such as copper and iron, will catalyze and accelerate the oxidation and deterioration of oil products, increase the viscosity of lubricating oil, and generate acidic substances to corrode mechanical parts. In particular, copper and lead have a greater impact, while the impact of metal salts depends on the ion type and concentration of the metal salts. Air and water will also aggravate the oxidation of lubricating oil.
Lubricating oil should be avoided from contamination during use, including water, dust, air, various impurities, other lubricating oils, etc. Various metal materials in certain metal equipment, such as copper and iron, will catalyze and accelerate the oxidation and deterioration of oil products, increase the viscosity of lubricating oil, and generate acidic substances to corrode mechanical parts. In particular, copper and lead have a greater impact, while the impact of metal salts depends on the ion type and concentration of the metal salts. Air and water will also aggravate the oxidation of lubricating oil.
Through oil testing, the degree of oxidation of oil products can be monitored to guide equipment maintenance.
Conclusion: As the "blood" of industrial equipment, lubricating oil failure = equipment failure. Therefore, the maintenance of equipment should pay special attention to the role of lubricating oil, select high-quality oil products, do a good job in the acceptance of new lubricating oil, do a good job in sealing and pollution control, and avoid mixing lubricating oil. When changing oil, pay attention to cleaning the old oil to avoid contamination of the new oil by the original deteriorated oil. Pay attention to oil testing, control the quality of new oil through oil testing, and guide the maintenance and fault diagnosis of equipment in use.
Conclusion: As the "blood" of industrial equipment, lubricating oil failure = equipment failure. Therefore, the maintenance of equipment should pay special attention to the role of lubricating oil, select high-quality oil products, do a good job in the acceptance of new lubricating oil, do a good job in sealing and pollution control, and avoid mixing lubricating oil. When changing oil, pay attention to cleaning the old oil to avoid contamination of the new oil by the original deteriorated oil. Pay attention to oil testing, control the quality of new oil through oil testing, and guide the maintenance and fault diagnosis of equipment in use.
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