ASME MFC-7 pdf download Measurement of Gas Flow by Means of Critical Flow Venturis and Critical Flow Nozzles 1 sCOPE AND FIELD OF APPLICATION This Standard applies only to the steady flow of single-phase gases through critical flow venturis (CFV) of shapesspecified herein [also sometimes referred to as critical flow nozzles (CFN), sonic nozzles, or critical flow venturinozzles]. This Standard...