The correct selection of lubricating oil is an important measure to ensure the safe and stable operation of the air compressor. Therefore, when selecting the special lubricating oil for the air compressor, we should not only consider the working load, movement speed, working temperature, lubrication mode and operating environment, but also start from the quality of the lubricating oil for the air compressor.

         1. The base oil of compressor oil generally accounts for more than 95% of the product oil, so the quality of base oil is directly related to the quality level of compressor oil, and the quality of base oil is directly related to its refining depth. The content of heavy aromatics and gum in the deep refined base oil is low, the carbon residue is low, the antioxidant sensitivity is good, the tendency of carbon deposition in the compressor system is small, and the oil-water separation is good. Base oil has a great influence on the performance of rotary compressor oil, so high quality hydrogenated mineral oil or synthetic oil is generally selected as base oil for screw air compressor oil.

          2. In the process of recycling, oil products are easily oxidized and deteriorated by contacting with high-temperature and high-pressure oxygen in compressed air to form various acids, resins, asphaltenes and other substances, which make the color of oil products darker, acid value higher, viscosity higher and sediment appear, so as to reduce the amount of oil injected, increase the temperature of oil products and machines, and cause excessive wear. Therefore, screw air compressor oil must have excellent oxidation stability to ensure long-term safe use of oil.

          3. The anti coking tendency of compressor oil is very important for the reliable operation of compressor oil. The main carbon residues in oil products are asphaltenes, resins and polycyclic aromatic hydrocarbons. Most of the above substances can be removed after deep refining. Generally, the carbon residue value of low viscosity and deeply refined lubricating oil is low, so it is not easy to deposit carbon in use. The coking tendency of oil products is the comprehensive performance of various indicators, which is influenced by many factors, and ashless additives should be selected as far as possible.

          4. During the operation of the compressor, the condensed water in the air is constantly met and stirred violently, which is easy to produce emulsification, resulting in unclear separation of oil and gas, and increase of oil consumption. Because the oil is emulsified, the oil film is destroyed, resulting in wear. Emulsified oil will promote the dispersion of dust, gravel and sludge, affect the function of the valve, increase friction, wear and oxidation. Therefore, high quality compressor oil has good anti emulsification performance and oil-water separation performance.