The Changing Face of Precision
Flow Measurement
Flowmeter Selection Process
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Tendency to stay with what’s worked in past
Gathering information often difficult
Not an Exact Science
•
Usually more than one answer
Potential LARGE gains
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Reduced CAPEX
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Reduced OPEX
Flow Technology Selection Process
Application/Purpose of Measurement
Actions: Review purpose of measurement, key
performance criteria, environmental
considerations, approvals
Purpose of Measurement
Performance
Actions: Complete Spec Sheet, Size Flowmeters
for application, complete Installed Performance
analysis
Installed vs Reference Performance
Cost/Economics
Actions: Consider schedule, price, cost to Install,
operating costs (Reliability, Maintenance, Energy, etc.)
Price/Installed Cost/Life-Cycle Cost
Select Flowmeter
$3.7 Billion
Market
Precision Flow Market
FY07 Precision Flow Market $Millions
Average CAGR: 6.3%
dP
Coriolis
Mag
Turbine
PD
Ultrasonic
Thermal Mass
Vortex
Technology CAGRs (’07-’12)
Why Coriolis – Direct Mass
Measurement
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Coriolis meters have been the fastest growing flow measurement
technologies over the past decade.
Growth has been driven by a unique ability to measure mass directly
– Better control of Chemical reactions (based on molecular ratios)
– Better Mass balance
– Reduced Process Variability especially in compressible fluids (Gas)
40.9 gal.
42.0 gal.
20° F
342 lbs.
60° F
342 lbs.
The same amount of fluid (342 lb)
looks like 2.7% difference with
volumetric measurement (42.0
vs. 40.9 gallons)
Slide 5
Theory of Operation
• The Coriolis effect is an inertia force.
• In 1835, Gustave-Gaspard de Coriolis showed that this inertia force must be
taken into consideration if the simple Newton’s Law of Motion of bodies are
to be used in a rotating frame of reference.
Gasparde de Coriolis
Coriolis Effect: The original path is deflected
westward by the rotation of the planet
Slide 6
Theory of Operation – Mass Flow
• In a Coriolis meter, the inertial force is provided by vibrating the flow tubes.
The tube twist or angle of deflection from the vibration plane is measured
and converted into a mass flow measurement.
• Most implementations use a pair of counter-vibrating tubes to cancel the
effect of external vibrations, but many geometries exist.
Flow
Axis
Flow Tubes
Flow
Vibration
Vibration
Twist
Micro Motion Confidential
Page 7
Slide 7
Theory of Operations – Mass Flow
• Process fluid enters the sensor and flow is split with half the flow through
each tube. The sensor flow tubes are vibrated in opposition to each other
by energizing a drive coil. Tubes are oscillated at their natural frequency.
• Magnet and coil assemblies, called pick-offs, are mounted on the flow
tubes. As each coil moves through the uniform magnetic field of the
adjacent magnet it creates a voltage in the form of a sine wave.
Slide 8
Theory of Operations – Mass Flow
• During a no flow condition, there is no Coriolis effect and the sine waves
are in phase with each other.
• When fluid is moving through the sensor's tubes, Coriolis forces are
induced causing the flow tubes to twist in opposition to each other. The
time difference between the sine waves is measured and is called Delta-T
which is directly proportional to the mass flow rate.
Slide 9
Theory of Operations – Mass Flow
– We also measure temperature – why?
– Compensates for the effect of temperature on tube rigidity (% change in
rigidity per 100°C).

Three wire platinum RTD measures
process temperature

Accurate to +/- 1.0oC

Available as additional process variable
RTD
Micro Motion Confidential
Page 10
Slide 10
Theory of Operation - Density
• Density measurement is based on the natural frequency of the system
including the flow tubes and the process fluid.
– As the mass increases, the natural frequency of the system decreases.
– As the mass decreases, the natural frequency of the system increases.
Slide 11
Theory of Operation - Density
• The density of the process fluid can be derived from the frequency of
oscillation of the sensor. This frequency signal is taken from one or both
pickoff coils.
• The volume of the fluid contained in the flow tubes remains constant, so
the only way mass can change is if density also changes. Because of this
relationship between mass and density, the natural frequency of the flow
tubes indicates not only the mass of the fluid contained, but also the
density.
Slide 12
Theory of Operation - Density
• Density calibration is performed at the factory on air and water.
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Tube period of air (K1) 10484
Tube period of water (K2) 10966
Density of air (D1) 0.0010
Density of water (D2) 0.9982
Temperature coefficient 4.39
Tube Period = 10817
Density = 0.6871 g/cm3
• The transmitter automatically performs
a calculation based upon the data points
stored in its memory during calibration.
• Field calibrations can also be performed
using air, water, or alternate fluids
depending on the density span desired.
Slide 13
Why Coriolis – Summary
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Multivariable Measurements
– Mass Flow, Volume Flow, Density, Temperature, % Solids, Concentration
– Measures liquids, Gases, and Slurries
Insensitive to fluid properties
– Pressure, Temperature, Density, or Viscosity
– Calibration on water transfers to all other fluids including gases
Easy to Install and Maintain
– Measures independent of flow profile, no Straight run required
– No Moving Parts
– Bi-directional
High Accuracy
– +/- 0.05% of rate Liquid Mass Flow
– +/- 0.10% of rate Liquid Volume Flow
– +/- 0.35% of rate Gas Flow
– +/- 0.0002 g/cc Liquid Density
– High turndown, >100:1 possible
– Batch accuracies to 0.10%
Slide 14
In-Situ Meter Verification
• Calibration
– Micro Motion Super Service Centers only reliable facility for calibrating
(or re-calibrating) meters!
– Typically, customers will request factory cal for master meters or cal
carts
• Validation
– Primary flow standards such as provers, flow labs, and master meters
– Required for regulatory, agency, or contractual agreements (AGA, API,
OLNL, Country Specific Custody Transfer requirements )
• Verification
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Most customers need to verify – not validate or calibrate
Secondary comparison such as cal carts, catch & weigh, etc.
Driven by Standard Operating Procedures and Quality Assurance
Troubleshooting
Easily Verify Meter Performance and Health
• “Can I tell if my Coriolis meter has changed?”
• “Can I detect when the meter is being coated?”
• “How often do I need to recalibrate my meter?”
Characteristics that alter meter performance
Erosion
Cracking
Pitting
Coating
“We calibrate manually by taking meters out of the
process, and it is a pain. It is an all-day deal and we pay
$2k to 3k per meter per year for this.” --- Oil & Gas
Customer
Using Verification in the Field
Meter Verification Process
Okay
Not Okay
Structural Integrity Measure
Trigger limits are tunable
0.06
Damage
Begins
0.04
P
Factory
Calibration
0.02
Erosion
P
P
0
Cracking
-0.02
Customer advised
“Not Okay” due to
measurement change
-0.04
-0.06
0
20
40
60
Measurement Number
Pitting
80
100
Coating
Sample of Verification Report
Micro Motion
Coriolis Flow and Density Leaders
• Unparalleled Value
– 31 years of flow and density measurement experience
– Over 600,000 installations
– 1700 dedicated flow and density specialists
• Product Breadth
– Widest range of flow and density measurement solutions
• Technology Leadership
– Continuous innovation driven by customer needs
– Committed to providing the highest performing measurement
devices available
Questions ???
Slide 20