Cameron NuFlo MC-II, User Manual

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MC-II Flow Analyzer
24
Example: Gas Measurement Using a Calculated Divisor
Calculating the divisor for gases is necessary when registering in units other than actual cubic feet (ACF). The
USEr volume and flow rate functions of the MC-II are used in this case.
Note—Each MC-II is shipped with a label set (Part No.100080190) containing commonly used flow rate and
volume units of measure labels. The appropriate label can be placed on the front panel on the right side of the
LCD viewing window.
Calibration Information
•
A NuFlo 2-in. high-range gas turbine meter will be used to measure gas flow with an average flowing
pressure of 120 PSIG and an average flowing temperature of 50°F.
•
The meter factor is 72.56 pulses per actual cubic foot (PACF).
•
The unit of measure for volume is to be cubic meters.
•
The unit of measure for the flow rate is to be cubic meters per day.
•
The standard conditions to compensate to are 60°F and 14.73 PSIA.
•
The atmospheric pressure is unknown, but the elevation is 1,000 feet above sea level.
Calibration Procedure
1. Calculate the divisor and divisor decimal point position using the following equation:
Divisor
=
FC × Ps × Tf × CON
(Pg + Pa) × Ts × (Fpv)
2
Where:
FC = Meter calibration factor in pulses per actual cubic foot (PACF)
Ps = Standard pressure in PSIA
Tf = Average flowing temperature in degrees Rankine (°R)
CON = Conversion factor for number of standard cubic feet (SCF) per unit volume of desired measure
Pg = Average flowing pressure in PSIG
Pa = Atmospheric pressure in PSIA
Ts = Standard temperature in degrees Rankine (°R)
Fpv = Supercompressibility factor (enter a factor of 1 if the supercompressibility factor is not known)
a. Determine the supercompressibility factor. In this example,
Fpv = 1.0102.
b. Determine the average atmospheric pressure at 1000 feet above sea level (14.21 PSIA). Pa = 14.21
PSIA
c. Determine the factor for converting Fahrenheit to Rankine (°R = °F + 459.67.)
Flowing Temperature (Tf) = 50 F + 459.67 = 509.67°R
Static Temperature (Ts) = 60 F + 459.67 = 519.67°R
d. Determine the factor for converting cubic feet to cubic meters. There are 35.31 cubic feet per cubic
meter; therefore, CON = 35.31.