The ASME Flow Nozzles are the most commonly used. The standard published by the American Society of Mechanical Engineers (ASME), ASME MFC-3M-1984, “Measurement of Fluid Flow in Pipes Using Orifice, Nozzle, and Venturi,” covers
the following three types of ASME Flow Nozzles.
• ASME high beta ratio nozzle: for beta between 0.50 and 0.80
• ASME low beta ratio nozzle: for beta between 0.20 and 0.50
• ASME throat tap flow nozzle: for beta between 0.25 and 0.50
These flow nozzles, shown in Figure 500-6, are elliptical-inlet, long-radius, wall-tap style nozzles.
Another standard flow nozzle is the ISA 1932 type, which is widely used in Europe but uncommon in the U.S. This type of flow nozzle is described in the ISO Standard 5167. It is not covered in the ASME standard or in this manual.