Compressors (air compressors, various gas compressors), freezers and vacuum pumps (mainly mechanical vacuum pumps) have special requirements for lubricating oils. Compressor oil is mainly used in the reciprocating piston gas compressors, pumps and piston pump displacement piston and piston friction part, into the exhaust valve lubrication, etc., used in the automatic oil lubrication system, there are also lubrication and compression Machine's main bearings, bearings and cross-head cross, skateboarding, etc., low viscosity is also used in various types of rotary compressor. Refrigerant oil is mainly used in compressing refrigerant compressors, vacuum pump oil is used in the vacuum system in the mechanical vacuum pump. The three have different purposes, but they have many things in common. For example, the three parts should not only take the lubrication function of the cylinder, piston, valve, bearing, skateboard and other parts, but also prevent the compressed gas channeling between the piston and the cylinder wall Gas seal, but also have the chemical stability of the gas does not work with the compressed gas. For reciprocating compressors, since the discharge temperature of the compressed gas is higher than that of the sucked gas, better viscosity-temperature performance, suitable viscosity and better oxidation stability are required, and deep-drawn base oils Naphthenic oil), adding anti-oxidation and anti-wear properties of the additive made of (generally not allowed to add pour point depressant and tackifier). For the rotary compressor oil because of its working conditions and lubrication and reciprocating compressors very different, so the quality of lubricants made more stringent requirements, in addition to rotary air compressor oil lubrication, cooling, sealing outside , But also prominently play the role of cooling the compressed gas, in the course of use, due to oil mist after mechanical collision and adsorption media separated from the gas, repeated cycles, the oil can easily be contaminated and aged, and in order to overcome the rotary centrifugal force, the need for oil Products have better adhesion, but the bearings do not need too much viscosity lubricant, so the rotary compressor oil is generally used to refine the narrow distillate base oil, and add composite antioxidant, rust, anti-anti Grinding, demulsification, defoaming additive production. For frozen oil, in addition to meet the above basic requirements, but also need oil has excellent low temperature performance, and the separation of the refrigerant or water is good. Therefore, the general refrigeration oil are used in the production of deep refining of low freezing point naphthenic oil production, it is noteworthy that, in the use of SO2 for refrigeration oil, the use of deep refining of aromatics and sulfur oxide-free lubricants (such as white oil ), Otherwise, will produce glial precipitation affect the freezer work. Chloroethane as a refrigerant, will dissolve the oil, the general use of glycerol and castor oil lubrication; ammonia or carbon dioxide as a refrigerant, the use of non-fat lubricating oil, because the fatty oil is easy to emulsify, is not conducive to water separation But to icing, and the thermal conductivity of the fatty oil is small, so that the freezing efficiency decreases. Vacuum pump oil is a special vacuum pump oil, although the pump has different types, but the oil quality requirements are the same. Vacuum pump in operation, the pump chamber oil plays a sealing role on the one hand, so that the pump to obtain the necessary degree of vacuum, on the other hand pump cavity by the friction, temperature, decompression, vapor pressure components of high evaporation To vacuum space pollution of the vacuum system, limit the increase of vacuum. The role of vacuum pump oil, in addition to the requirements of the appropriate viscosity, high viscosity index, good oil-water separation, excellent thermal oxidation stability, the most important quality requirements are low saturated vapor pressure and extreme limits to ensure high The degree of vacuum. Therefore, in the production of vacuum pump oil in addition to select the appropriate type of base oil, but also should be a single narrow distillate oil or pure chemicals and as far as possible without blending a few distillates.