Invensys receives patents for flowmeter technology

Feb 22, 2005

Invensys has received two additional patents for the core technology of the company's award-winning Foxboro CFT50 Digital Coriolis mass flowmeter. U.S. patent numbers 6,754,594 and 6,758,102 apply to the Digital Coriolis flowmeter and its ability to correct for two-phase flow.  These techniques relate to the CFT50's ability to accurately measure traditionally difficult-to-handle materials and gas/liquid (two-phase) flow. Two-phase flow is a major contributor to process interruptions, measurement inaccuracies, and deviations in product quality.
The new patents relate to new signal processing techniques used to provide useful measurements of both mass flow and density and the operational aspects of keeping the Coriolis meter running stably in single-phase or two-phase flow conditions (and dynamic transitions between these flow conditions).  The first patent includes an advanced control and measurement system with high-speed digital signal processing that responds to changing flow conditions many times faster than standard Coriolis flowmeters.  The second patent relates to detecting and compensating for two-phase flow conditions and generating a validated mass flow measurement.  (Traditional Coriolis flowmeters either stall or provide inaccurate measurements in two-phase flow situations.)
The Digital Coriolis flowmeter technologies were developed through a collaborative program between the Foxboro Measurements and Instruments Division of Invensys Process Systems and Oxford University in the UK. These technologies are incorporated into the Foxboro CFT50 digital Coriolis mass flow transmitter.  Introduced in 2002, the CFT50 has won numerous awards, including Best of Show in the ISA 2002 New Product Showcase.
For more information on the CFT50 mass flow transmitter or other advanced Foxboro measurement and instrument devices, readers can contact their local Invensys/Foxboro representative, visit the Foxboro Measurements and Instruments Web Site at or call 866-746-6477 (508-549-2424 outside the U.S. and Canada). The CFT50 mass flow transmitter can also be purchased on-line at