Method and apparatus for correcting for performance degrading factors in coriolistype mass flowmeter

摘要

Drivers 46 and sensors 48 in Coriolis-type mass flowmeters 10 are used to monitor and predict flowmeter failure modes due to mechanical deterioration during meter operation. The relative values of two different signals, e.g, resonant frequencies, associated with Coriolis flow conduit motion are monitored as an indicator of excessive mechanical deterioration and also used to compensate for shifts in meter factor. The noise spectrum of the sensor output is also monitored to indicate mechanical fatigue of the tubes. Energy loss in the vibrating tubes 20, 26 is monitored as an indication of fatigue to determine tube failure by determining the drive power needed to maintain constant velocity oscillation or measuring the decay rate of the drive signal when driver power is interrupted.