AbstractWhen gases with different chemical and physical properties are compressed, the type of lubricant to be used in compressing equipment must be given careful consideration. Basically, this equipment can be categorized as reciprocating or rotary. This paper describes the lubrication of reciprocating compressors. The development of lubricants for use in specific applications, such as the compression of air, natural gas, etc., is discussed in detail. This will include a section dealing with the development and use of screening tests to predict the performance of candidate lubricants, the role of current international specifications, compressor rig tests and field applications. The advantages and disadvantages of mineral oils and synthetic fluids in various applications will also be described in detail.