The equations PIPE-FLO uses for flow meters are from ASME Standard, Measurement of Fluid Flow in Pipes Using Orifice, Nozzle, and Venturi (ASME MFC-3M-1989) and ASME Standard, Measurement of Fluid Flow Using Small Bore Precision Orifice Meters (ASME MFC-14M-1995).

Orifices
          Limits:
               2” ≤ D ≤ 36”
               0.20 ≤ β ≤ 0.75
               2000 ≤ Re ≤ 108
               p₂/p₁ ≥ 0.75
Small Bore Orifices
          Limits, Corner Taps:
               0.5” ≤ D < 2.0”
               0.10 ≤ β ≤ 0.80
               Re > 1000
          Limits, Flange Taps:
               1” ≤ D ≤ 2.0”
               0.15 ≤ β ≤ 0.70
               Re > 1000
Nozzle
          Limits:
                4” ≤ D ≤ 30”
                0.20 ≤ β ≤ 0.80
               10⁴ ≤ Re ≤ 6 x 10⁶
               p₂/p₁ ≥ 0.75
Venturi Tubes
           Limits, Rough-cast and Rough-welded Convergent
               4” ≤ D ≤ 48”
               0.30 ≤ β ≤ 0.75
               2 x 10⁵ ≤ Re ≤ 6 x 10⁶
               p₂/p₁ ≥ 0.75
          Limits, Machined Convergent
               2” ≤ D ≤ 10”
               0.30 ≤ β ≤ 0.75
               2 x 10⁵ ≤ Re ≤ 2 x 10⁶
               p₂/p₁ ≥ 0.75

 

Reynolds Number Out of Range: This warning means that the Reynolds number is outside the Reynolds number range specified by the standard.

Pressure Ratio Out of Range: This warning means that the pressure ratio is outside the pressure ratio range specified by the standard.

Beta Ratio Out of Range: This warning means the beta ratio is outside the beta ratio range specified by the standard.