In the kingdom of the blind, the one-eyed man is king. In my opinion, this statement could almost be used to describe the present state of the art of designing and applying gas-oil separator elements to flood lubricated screw compressors used in refrigeration machines. This paper will deal exclusively with this type of compressor as it may largely replace the piston and centrifugal types on all but the very small and very large machines.

Separators may not be required with reciprocating or centrifugal compressors as they add little or no oil to the gas during compression. The flood lubricated screw, however, mixes large quantities of oil in with the gas. This oil must then be separated from the gas to prevent it from accumulating at other locations downstream.