This module includes detailed information on compression ratio and volumetric efficiency. Practical examples and solutions are included to help the reader understand why some systems are more efficient than others. The discharge and suction strokes of reciprocating compressors and how they relate to compression ratio and volumetric efficiency are explained. Also covered in this module are;System floodingMigrationSluggingAutomatic pump-down systems—with electrical circuit analysisCrankcase heatersSuction line accumulatorsOil separators Compressor performance curves and graphs, compressor specifications, parallel compressors and their oil systems are also explained in detail. Voltage variation is explained as it applies to compressors. A solid understanding of the compression system is necessary to successfully perform field service.