Two Stage Air Compressor Test Rig consists of a double stage reciprocating type air compressor driven by 2 HP Motor through a belt. The outlet of the air compressor is connected to reservoir (Tank) and suction is connected to another air tank with a calibrated orifice plate and a water manometer. Bellow is fitted on one side of the air tank to regulate the flow. Temperature of inlet air, after single compression, inlet and outlet of second compression and pressure in reservoir and at intermediate stage can be measured by Temp. Sensors and gauges.