We are using Micro Motion F-Series Flow Meters to measure the Flow of Oil and Water at Test Separator outlet. F200H (Note:-01) with Transmitter 1700 is used to measure Water Flow (Range 0 to 1800 USB/day) & F300H (Note:-02) with transmitter 1700 is used to measure Oil Flow (Range 0 to 5000 USB/Day). Please answer the following;

1. What is the minimum flow that can be accurately measured by each meter?

2. How to compensate the flow so that we can get Standard USB/day flow? (I understand that mass flow meter is measuring Actual USB/Day Flow; i.e. mass-flow divide by actual density )
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Note: 1 F200H 999 C C A Z E Z Z Z X 17017 NTMC with Transmitter 1700 | 11DEFEZZX _13079

Note: 2 F300H 999 C C A Z E Z Z Z X 1642 HTMC with Transmitter 1700 | 11DEFEZZX _13079</pre>

 

The advantage of Coriolis Mass Flow Meter is that it gives flow rates directly in mass without a need for temperature/pressure compensation. The read that is being displayed by your flow meter is nothing but mass flow reading. Though volume flow is a possibility even in mass flow but generally Coriolis is preferred to read in mass. You don't need further compensation to be done.

 

1.look at the user manual dude, check the TURNDOWN RATIO. Divide the maximum flow to the turndown ratio then you will get the minimum flow that your flow meter can handle. but in special cases the flow range can be affected by certain factors like temp, press and density. its best to contact Emerson sales rep.

2.if you need to measure volumetric flow rate you don't need to compensate it, but if you measure mass flow rate you have to compensate for density changes.

3.its really best to contact your sales rep dude!

 

There is always some confusion about flow measurement (and especially gas flows).

The historical method for measuring flow was to use volumetric meters giving the volume at flow conditions. This measurement has first to be compensated for the temperature and pressure effects on the sensor (not the fluid). There is then usually temperature and pressure measurement and correction back to standard conditions i.e. derive the volume flow at 1bar and 15C or whatever constitutes the base conditions where you are.

You may have an analyser bypass measuring the density at the temperature and pressure in the bypass. This measurement is usually first compensated for the temperature and pressure effects on the sensor to derive the corrected density for the measurement conditions. In some cases Velocity of sound corrections may also be required.

The density is then converted to the density at base conditions.
You now have density and volume at base conditions (the reason for this is that the density, measured in a by-pass may be at different conditions to the fluid in the flow meter. Density must always be corrected to base conditions from observed (correcting for both temperature and pressure) so then you would have to calculate the density at the alternative (flowmeter) conditions to obtain mass. Hence the volume and density are both converted to base conditions).

Barrels are volume measurements.

So if you use mass flow you need to get from mass to volume.
The mass meter delivers the mass flow rate and it delivers the density at the flowing conditions. You can use this measurement (first corrected for the effects of temperature and pressure on the sensor, these can be significant for coriolis meters operated away from calibration conditions) and then you need to density at base conditions to derive the standard volume.

This whole mass Vs Volume thing causes all sorts of confusion from using volume meters and basing payment and tax on mass. Like I said, it gets even more confused with gas flows for some reason.

 

Of all people, I should have remembered that many volumetric meters also can have viscosity compensation.

Turbine flomwters, for example, suffer a loss of linearity and a shift in the meter factor with viscosity.

Companies like FTI use temperature as an index to the fluid viscosity and having calibrated the sensor on a range of viscosities then select the appropriate calibration curve for the meter. Other companies such as Smith meters use online viscosity measurement to select the correct calibration curve.

PD meters can also suffer from the effects of viscosity though the effect is much less. This is due to the working tolerances of the meter allowing a certain amount of "slip flow". The thinner the fluid, the more of the fluid which can flow through the working tolerance without being registered. Most usually PD meters are calibrated (and provided the appropriate clearances for) certain viscosities. However there is a very simple relationship between viscosity and meter correction.

Note that in some case meters can become "over positive". This is most common with rotary piston type meters or other meters with free floating moving elements. The high viscosity fluids, instead of flowing through the working tolerances, form a static boundary layer which effectively reduces the swept volume causing the meter to over register fluid flow.