Theoretical and experimental studies on oil injected twin-screw air compressor when compressing different light and heavy gases

Oil injected twin-screw compressors are widely used for medium pressure applications in many industries. Low cost air compressors can be adopted for compression of helium and other gases, leading to significant cost saving. The efficiency, delivery rate and the heat of compression of the compressors (medium and small size) has been analyzed and presented in the study. To generate machine independent experimental data, two similar compressors with different capacities have been setup to test the performance of air compressors when applied to compress nitrogen, argon and helium gases apart from air. Also this paper addresses the gas delivery rate and heat of compression (temperature) on volumetric and power efficiency.