The coking of air compressor oil is actually caused by a series of changes in the oil product. We all know that air compressor lubricants are organic compounds, and oxidation reactions are bound to occur. Oxidation may break the molecular chain or cross-link the molecules. When the deep oxidation occurs, the viscosity of the oil will increase significantly, and when it exceeds a certain range, coking of the oil will occur.

Therefore, the main reasons for the coking of air compressor oil are as follows:

1. Metal ions: Debris inside the compressor will not only block the oil system, but also a catalyst for oil oxidation. The presence of iron and other metal ions acts as an initiator for the polymerization of certain hydrocarbons. The higher the water content in the oil, the higher the temperature, and the greater the tendency of metal to catalyze. Therefore, the metal wear debris in the oil should be removed in time.

2. Oxidation: Air compressor oil reacts with oxygen, sulfur and other substances in the air under high temperature and metal catalysis to produce alcohols, aldehydes, ketones, acids and oxides. Under the long-term action of oxygen and high temperature, some hydrocarbons will polymerize to form insoluble matter. The higher the pressure of the air compressor, the greater the oxygen concentration, the more intense the degree of oxidation of the oil, and the shorter the life of the oil.

3. Moisture influence: As the air compressor oil often comes into contact with the compression medium, the moisture in the air will condense and enter the oil after compression. In addition, the violent agitation during the operation of the unit makes the "oil" and When the two liquids of "water" are mixed together and used for a long time without changing the oil, one phase of the liquid is dispersed into many particles and molecules dispersed in the other phase of the liquid to become an emulsion. The emulsified oil will not only reduce the lubrication effect, but also cause the additives or base oil to undergo hydrolysis and other reactions, causing the equipment to rust. The rust is gradually deposited, seriously forming part of the sludge or coking material.

4. Influence of old oil: Most of the current air compressors use mineral oil or semi-synthetic oil based on mineral oil, and the life span is generally between 2000-4000 hours. This kind of oil usually has coking after two years of operation. This phenomenon occurs even during a normal oil change. Because it is impossible for the oil to drain 100% of the sunken oil every time, the remaining old oil is deposited at the low point of the oil circuit, and then participates in a new round of oil circuit circulation together with the new oil. After a certain period of operation, the oil quality will deteriorate and occur coking.