Applying Coriolis Flowmeters

Coriolis Flowmeter
Courtesy Yokogawa

Coriolis mass flow meters are widely used throughout the process measurement and control field. Their basic operating principle, combined with modern sensor and signal processing technology, provide a list of potential application advantages.

• Directly measure mass flow based on the principle of measurement.
• No "moving" parts (except the slightly vibrating sensor tubes).
• Coriolis sensors have the ability to measure flow of non-conductive fluids.
• Measure the mass flow rate with high accuracy.
• Instruments can be applied across a wide usable measurement range.
• Deliver density measurement based on oscillating frequency.
• Not materially impacted by fluid viscosity or density.
• Coriolis flow meters also do not need lengthy straight pipe sections upstream or downstream of the sensing unit.

SELECTION AND INSTALLATION RECOMMENDATIONS

Some considerations for product selection and installation of Coriolis mass flow meters:

• Rapid temperature changes within the measured medium can impact measurement accuracy.
• Wide ranges of connection types are available, specify the best match for your system.
• Select sensor tube construction material to accommodate media characteristics.
• For liquid measurement, the sensor tube will extend downward from a horizontal pipe run. 
• As with most industrial products, there may be restrictions on where the device may be used. For example, not for use in aircraft. Assure that your application conforms with the intended usage of the instrument.
• Install at least one tight shutoff valve adjacent to the instrument for purposes of zeroing. Isolation valves for inlet and outlet are preferred.
• Follow manufacturer recommendations for pipe supports, if required, at inlet and outlet sides of the unit
• Avoid installation at locations with high levels of vibration or strong electrical fields.
• Locate the sensor unit at the lowest practical level in the piping system. This helps avoid collection of gas bubbles in the sensor tubes.
• Sensor tubes need to be completely filled with subject medium to obtain accurate measurement.
• Avoid the use of flexible connections and reducers at the unit connection points, unless in accordance with specific manufacturer guidelines.

The Coriolis flow meters of different manufacturers may have some particular recommendations, all of which should be followed to insure the best available performance, safety, and longevity of the unit.

Share your process instrumentation challenges and requirements with process measurement specialists, combining your process knowledge and expertise with their product application experience to develop effective solutions.

Vortex Flowmeter Delivers High Performance in Harsh Process Conditions

digitalYEWFLO Vortex Flowmeter
Courtesy Yokogawa

In the process measurement and control field, vortex flowmeters are noted for their ruggedness, versatility, comparatively high accuracy, and absence of moving parts. They are compatible with numerous applications requiring measurement of flow in gases, liquids, and steam. The Yokogawa digitalYEWFLO vortex flowmeter is an accurate and stable device, even in harsh process conditions, and has a highly reliable and robust design that can deliver improvements in plant efficiency and reduced operating costs. It is available in several versions, one of which is multivariable, providing a calculated mass flow rate output.

Operating Principle

When a shedder bar is placed in a flow, Karman vortices are generated on the downstream side of the bar. The Karman vortices are detected by two piezoelectric elements installed in the upper part of the shedder bar. The vortex frequency is proportional to the flow velocity in a specific range of Reynolds numbers. Therefore, flow velocity or flow rate can be determined by measuring vortex frequency.

Noise Reduction

Noise caused by strong piping vibration may affect the accuracy of vortex frequency detection. The two piezoelectric elements in the digital YEWFLO are installed in a configuration that is polarized, so they are not affected by vibration in the flow or vertical directions. The noise of vortex (lift)- direction vibration is reduced by adjusting the outputs of the piezoelectric elements. Combining these features with the Spectral Signal Processing (SSP) function provides optimum and stable measurement.

Share your process measurement challenges with a product application specialist. The sharing of ideas and information will produce the best outcome.

Yokogawa digital YEWFLOW Vortex Flowmeters from Miller Energy, Inc.

Coriolis Mass Flow Meter - Operating Principle, Applications, Advantages

Coriolis Flow Meter - Courtesy Yokogawa

Coriolis mass flow meters are widely used throughout the process measurement and control field. Their basic operating principle, combined with modern sensor and signal processing technology, provide a list of positive aspects.

Directly measure mass flow rate based on the principle of measurement.

Measure the mass flow rate with high accuracy of ±0.1%.

Provide a wide usable measurement range.

Deliver density measurement based on oscillating frequency.

Not materially impacted by fluid viscosity or density.

Coriolis flowmeters also do not need straight pipe sections upstream or downstream of the flowmeter. They also have the ability to measure non-conductive fluids. 

I have included an interesting video, produced by Yokogawa, a world class manufacturer of industrial process measurement and control instrumentation. It provides a clear and insightful illustration of the Coriolis principle and how it is used to provide accurate mass flow measurement.

Share your process measurement and control challenges with an instrumentation specialist. Combining your detailed process knowledge and their product application expertise will yield positive solutions.

Thermal Mass Flow Controller - Product Enhancement

Newly Enhanced Thermal Mass Flow Meters
And Electronic Pressure Controllers
Courtesy Brooks Instrument

Brooks Instrument, world recognized leader in thermal mass flow controllers and mass flow meters, has improved upon its premier family of smart digital thermal mass flow controllers and meters. The newly enhanced SLA Series features:

Enhanced temperature stability
Upgraded electronics
Improved accuracy
Zero-drift diagnostics
High turndown ratio

Multiple communication protocol support, and more.

The video included below will show you all the latest improvements on this product line that has thousands of units in its installed base throughout many industries and applications.

Application assistance and detailed information is available from product specialists. Combine their product and application knowledge with your own process expertise to generate a positive outcome.