Problems with using the Weiba flow meter to measure steam flow
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Today, while checking the DCS program, I noticed that the steam flow rate was calculated using certain conversions shown in the diagram. I contacted the designers and was told that Veritas flow meters are being used on site. Is this calculation method correct?
The instruments used for on-site inspection are differential pressure transmitters that output 4-20mA signals; it’s not certain whether they are VeriFlow meters. For now, we’ll assume they are such meters. Does every VeriFlow meter require this kind of conversion to determine the actual flow rate? What do the numbers resulting from the final CPT calculation represent?
The problem has been resolved; it’s simply a matter of applying the calculation formula for orifice plate flow meters, where Q represents the volume flow rate, in Nm3/h； K---coefficient ； d---Orifice diameter of the throttle element under operating condition, mm ； E---Coefficient of expansion ； a----flow coefficient ； AP---actual differential pressure, Pa ； p---density under medium operating conditions, kg/m3.
If the differential pressure flow meter does not apply squaring to the readings, then squaring is performed at the DCS side; from the configuration perspective, it is the DCS side that carries out this squaring