The type of air compressor oil is selected according to the design type, environmental conditions and operating load of compressor oil. Generally, L-DAB oil is selected under long-term high temperature environment (%; 26gt; 30 ℃), and low viscosity compressor oil is selected for high-speed water-cooled or low-pressure compressor with small compression ratio.
The base oil of compressor oil can be divided into mineral oil type and synthetic oil type. The production of mineral oil type compressor oil is generally made by solvent refining, solvent dewaxing, hydrogenation or clay supplementary refining, and then mixed with a variety of additives.
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 product oil, and the quality of base oil is directly related to its refining depth. The base oil with deep refining has less heavy aromatics and gum. Low carbon residue, good sensitivity of antioxidant, high quality of base oil, low carbon deposition tendency in compressor system, good oil-water separation, and relatively long service life.
The working condition of compressor oil is studied. It is considered that improving the composition of base oil is the key factor to improve the quality of compressor oil. After the compressor oil mixed by light and heavy components is injected into the compressor cylinder, the light components leave the working part ahead of time due to strong volatility, which affects the lubrication effect, while the heavy components cannot leave the working part quickly after completing the task due to poor volatility, which is easy to form carbon deposit under the action of heat and oxygen for a long time. Therefore, under such working conditions, the lubricating oil should choose the component oil with narrow fraction instead of the component oil mixed with multiple fractions.
Under the condition of dynamic lubrication, the film thickness increases with the increase of oil viscosity, but the friction also increases with the increase of oil viscosity. Low viscosity lubricating oil is not easy to form strong enough oil film, which will accelerate wear and shorten the service life of parts. On the contrary, if the viscosity of the lubricating oil is too high, the internal friction will be increased, the specific power of the compressor will be increased, so that the power consumption and oil consumption will be increased, and deposits will be formed in the piston ring groove, the air valve and the exhaust passage.