The secrets between compressor oil and compressors

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The secrets between compressor oil and compressors: Users are not very aware of the actual impact that the compressor itself has on the lifespan of the compressor oil, especially in the case of screw air compressors with oil injection. The truth is that even when the same compressor oil is used in compressors of different types, with varying parameters, different compression media, and under different operating conditions, its lifespan can vary significantly. See the analysis below: 1) If the exhaust temperature of a screw air compressor equipped with oil injection is reduced by 8–10°C, the lifespan of the oil will increase by roughly half ； 　　2) The discharge pressure of single-stage oil-injected screw compressors ranges from 0.3 to 1.3 MPa; due to differences in discharge temperature and oxygen partial pressure, the oxidation rate of air compressor oil varies significantly. For a low-pressure air compressor with an exhaust pressure of 0.3 MPa, the actual service life of its lubricating oil is 3 to 5 times longer than that of the oil in an air compressor with an exhaust pressure of 1.3 MPa ； 　　3) The lubricating oil of nitrogen compressors is not affected by oxygen, resulting in a significantly longer actual service life compared to compressors of the same type ； 　　4) The oleic value of screw compressors used for compressing carbon dioxide gas tends to exceed the specified limits, resulting in a short actual service life ； 　　5) The atmospheric-pressure oil-injected screw air compressors with two-stage compression achieve high efficiency due to the low oxygen partial pressure and low exhaust temperature in each stage; moreover, the actual service life of the lubricating oil is about twice that of single-stage compressors of the same type ； 　　6) Single-stage screw air compressors with a high compression ratio have a short oil lifespan ； 　　7) In variable-frequency oil-injected screw air compressors, the exhaust temperature is low during variable frequency operation; as a result, the shear force exerted by the compressor on the lubricating oil is less than that in conventional air compressors, allowing the lubricating oil to have a longer actual service life. The actual service life of the lubricating oil varies depending on the variable frequency duration and depth ； 　　8) Some air compressor manufacturers and users, in order to improve energy efficiency, have enlarged the fans of air-cooled oil-injected screw air compressors, thereby reducing the exhaust temperature of the screw compressors. This not only reduces power consumption but also extends the service life of the compressor oil, achieving two benefits at once ； 　　9) The actual service life of centrifugal compressor oil and piston compressor oil is much longer than that of oil-forced screw air compressor oil.