Compressor oils

Fouling Industrial streams may contain condensable or reactive components which may coat, solvate, fill the free volume, or react with the membrane. Gases compressed by an oil-lubricated compressor may contain oil, or may be at the water dew point. Materials that will coat or harm the membrane must be removed before the gas is treated. Most membranes require removal of compressor oil. The extremely permeable poly(trimethylsilylpropyne) may not become a practical membrane because it loses its permeability rapidly. Part of the problem is pore collapse, but it seems extremely sensitive to contamination even by diffusion pump oil and gaskets [Robeson, op. cit., (1994)]. 

Oils used in process machinery lubrication are generally of low viscosity and are laiovvm as turbine oils or compressor oils. Such oils vv oiild hav e a viscosity of 78 centiStokes at 4(F C (40 Savbolt Seconds... 

Kompressorol, n. compressor oil. komprimierbar, a. compressible. Komprimierbarkeit,/. compressibility, komprimieren, v.t. compress, kompromittieren, v.t. compromise. 

A V-belt-driven, force-fed oil lubrication system is used on water-cooled compressors. Oil goes to both bearings and to several points in the cylinder. Ten times as much oil is recommended to lubricate the rotary cylinder as is required for the cylinder of a corresponding reciprocating compressor. The oil carried over with the gas to the line may be reduced 50 per cent with an oil separator on the discharge. Use of an aftercooler ahead of the separator permits removal of 85 to 90 per cent of the entrained oil. 

For the general performance of compressor oils, there is DIN 51506. This specification defines several levels of performance, of which the most severe - carrying the code letters VD-L - relates to oils for use at air-discharge temperatures of up to 220°C (428°F). 

The oil in a refrigeration system should remain as clean as it is when it enters the compressor (unlike that of the automobile engine which is quickly contaminated by fuel, water, carbon and atmospheric dust). The condition of the compressor oil is therefore a direct indication of the physical and chemical cleanliness of the system. 

At the end of the shake-down period all strainers and filters are cleaned ready for the final test. If compressor oil is seen to be contaminated, this should be changed (see Section 11.10). 

CNG fuel systems can thus be subjected to compressor oil and condensed water vapor that would not occur otherwise if the gas had not been compressed. The compressor oil is probably more of an operating problem than a materials compatibility problem, though new CNG vehicle fuel systems that use multi-point fuel injectors may encounter some problems. 

Others Phosphate esters Silicone oils Halogenated fluids Polyphenyl ethers Fire resistant hydraulic fluids, gas turbine oils High temperature hydraulic fluids, brake fluids, compressor oils Extremely fire-resistant hydraulic oils Radiation-resistant, heat transfer fluids... 

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