Interpretation of failure causes and discrimination methods of lubricating oil by manufacturers of lubricating oil composite additives
1. Causes of lubricating oil failure
(1) High temperature effect
① If the lubricating oil is in high temperature environment for a long time, it will oxidize and become black and thick.
② The corrosion inside the lubricating oil increases, such as acid substances formed during engine operation.
③ Increase of carbon deposit, oil sludge, paint film and other substances.
It mainly comes from dust in the air, metal abrasive particles, leakage (fuel oil, water, etc.), lubricating oil oxides and substances produced by fuel combustion.
(3) Additive failure
The performance of some lubricating oils is degraded due to the failure or depletion of additives. For example, if the antiwear agent in the lubricating oil is used up, the antiwear property will be reduced.
(4) Viscosity index enhancer failure
Because of the long chain break of its organic molecules, it no longer has the effect of viscosity increasing.
(5) Base oil failure
Base oil is the carrier of additives. If the base oil fails, the additives will not play a role.
2. Judgment method of oil failure
Although there are national standards to determine whether to replace the engine lubricating oil, most car owners or maintenance personnel change the oil mainly according to the vehicle mileage / time (specified by the manufacturer) and the color and viscosity of the lubricating oil. In fact, the above methods are unreasonable. For example, judging by the color, some brand new lubricating oils appear black. Some lubricating oils may turn black if they add too much detergent dispersant. At this time, the lubricating oil does not fail, which may lead to misjudgment for inexperienced people. A simple and effective way is to judge whether the lubricating oil fails with the help of filter paper or electronic instruments.