Compressor Oil | Types And Options
Everybody talks of the compressors that are available these days. Be it centrifugal air compressor, reciprocating ones or rotary ones. Almost always in these discussions is the compressor oil used in these systems is mentioned but usually as a secondary thing and not given much attention to.
However, compressor oil deserves equal attention since it plays a major part in the efficient running of these systems. The compressor oil not only provides mechanical transfer of energy but also provides a hydraulic seal so that the compression process is improved. For each type of compression system however, there is different compressor oil. This implies that it is very important for the user of for example the centrifugal compressor to use the compressor oil for the centrifugal compressor and not for any other types of compressors.
The reason to this differentiation of the compressor oil is that for each system, they have a differently manufactured texture, viscosity, density and stickiness. In the market, compressor oil is recognized by its grades. Typically these are 32, 46, 68, 122, 220 and 264 graded and you choose the compressor oil or air compressor oil that best fits your compressor system.
For a screw compressor, grade 32 and 46 of the compressor oil are requires. This system uses the technique of oil flooding which enters the system and then drains away and thus the compressor oil required has to be of an average viscosity. Grade 32 and 46 fulfill the criteria.
Because a rotary compressor requires the compressor oil to stick to the blades and thus provide a seal, it requires the oil to be of a very high viscosity. For this, grade 122 and 264 fit best.
Similarly, a centrifugal compressor requires the compressor oil to stick to the blades to avoid friction and heat up of the system. For this purpose again, grade 220 and 264, those with a high viscosity are required. These grades, because of their high viscosity, can bear high levels of temperatures; even up to 60 degrees centigrade thus making them fit for the centrifugal compressor.
For a reciprocating system, the grades of compressor oils required are 122, 68 and 220. Again, the reason for the centrifugal one applies here. In this case too, the heat produced as a byproduct is high and therefore the oil that lubricated the working of the piston should be of a high viscosity and resistant to higher temperatures.
Even though the higher grades of the compressor oils are very viscous in nature and stick quite firmly to the compressor systems, the maintenance of oil is very important. This compressor oils that lubricate the compressor systems is like the blood in our veins. If it dries up or it made dirty, the body would not be able to fulfill its requirements. Similar is the case with the compressor systems. If the compressor oils dries up or is faulty in the sense that it is not performing its duty well the entire system suffers. Usually, this suffering is in the form of heat up and then seizures of the entire compressor.