TABLE OF CONTENTS Special compressors are available that need no lubrication, and refrigeration systems using this type of compressor can be free of oil. The cost to buy and operate an oil-free compressor is much greater than that of the lubricated type, so practically all industrial refrigeration plants use lubricated compressors. The need for oil is only to provide lubrication between moving parts and to seal certain openings in the compressor. No situation can be imagined where oil is beneficial elsewhere in the refrigeration system.
This chapter emphasizes the knowledge that is useful and even necessary in many cases for the designer, manager, or operator of a refrigeration system. This knowledge includes the types of oils encountered in industrial refrigeration, the terminology describing some physical properties of oils and the significance of these properties, how to prevent oil from passing into the system beyond the compressor, and how to remove from the system the oil that does escape the compressor package.
The manufacturer of the lubricating oil is an obvious resource for specific information on the oil sold by that firm. The relative quantity of oil sold for lubricating refrigeration systems is small in comparison to other uses of oil, so there is only a limited number of suppliers selling oil for refrigeration purposes. The manufacturer of the compressor is one of the best sources of advice on which oil to choose, because the compressor builder accumulates the experience of many users. A plant manager who...
