Abstract: There were some prombles in the the products quality inspection process of the displacement air compressor,for instance the lack of volume flow measurement,uncertainty analysis and test method integrallty and systematically.Thus researched flow testing method for displacement air compressor based on the ASME nozzle flow measurement method,which can be used to caculate volume flow when the performace parameters such as the atmospheric pressure,the first grade suction temperature,the nozzle upstream gas temperature and the nozzle pressure difference et al,were gotten by performance tests.At the same time,the uncertainty of flow measurment results also can be obtained.Three types displacement air compressor of one compressor manufacturing company,ie DG22HA type,JG22HA type and LG22A type were taken as an example for application of the ASME nozzle flow measurement method.Their volume flows were 3.37,3.33 and 3.43 m³/min,and their uncertainties were 0.016,0.016 and 0.017 respectively.Results show that the method can accurately obtain the volume flow of compressor simply and effectively.It is useful for air compressor production department for product performance test and design.

Key words: displacement air compressor, ASME nozzle, volume flow, uncertainty, measurement test