New patent for flow measurement

By Plant Engineering Staff December 12, 2005

Invensys has received a patent for digital technology that optimizes startup and operations for its Foxboro CFT50 Digital Coriolis mass flowmeter. U.S. patent number 6,950,760 B2 applies to Invensys techniques for selecting optimal mode of operation for accurate flow measurement during changing flow conditions.

The newly patented process keeps the Coriolis meter running stably in single-phase or two-phase flow conditions through precise digital analysis of flow measures at startup and at transitions between operational modes. For example, during startup, the mode of operation could include a random sequence of flow sensing. Once a consistent flow is determined, the digital flow meter analyzes and synthesizes these conditions for accurate flow measurement. If flow conditions change, the flowmeter will revert back to a previous mode to regain flow accuracy. High-speed digital signal processing allows the meter to respond to changing flow conditions many times faster than standard Coriolis flowmeters, making the CFT50 even more suitable for startup and ending process flow conditions in which two-phase flow is prevalent.

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.