Micromotion Gmbh

Rosemount Inc.

Other

James R Ruesch

Roger L Frick

Donald Reed Cage

Timothy J Cunningham

Charles Edwin Goetzinger

Earl A Grindheim

Stability coriolis mass flow meter

Apparatus and accompanying methods for implementing both an accurate densimeter and a net oil computer utilizing a common Coriolis meter assembly is described. This apparatus measures density of an unknown fluid by first determining the period at which both flow tubes contained within a dual tube Coriolis meter oscillate while the unknown fluid passes therethrough. The apparatus then squares the result. Thereafter, the density of the unknown fluid is determined as a linear function that relates the squared tube period measurement for the unknown fluid, and squared tube period measurements and known density values for two known fluids, such as air and water, that have previously and successively passed through the meter during calibration.

Apparatus and methods for measuring the density of an unknown fluid

Apparatus and accompanying methods for implementing both an accurate densimeter and a net oil computer utilizing a common Coriolis meter assembly is described. In essence, this apparatus measures density of an unknown fluid by first determining the period at which both flow tubes contained within a dual tube Coriolis meter oscillate while the unknown fluid passes therethrough. This apparatus then squares the result. Thereafter, the density of the unknown fluid is determined as a linear function that relates the squared tube period measurement for the unknown fluid, and squared tube period measurements and known density values for two known fluids, such as air and water, that have previously and successively passed through the meter during calibration. When used as a net oil computer, the inventive system obtains mass flow and temperature measurements from the same flow tubes. By using measured density and mass flow values of an oil-water emulsion that flows through the same Coriolis meter, the inventive system can advantageously provide both volumetric and mass based measurements of the flow rate and totalized flow of the entire emulsion and of the individual water and oil components present therein.

Net oil computer

A method and electronic circuit for measuring the density of substances flowing through an oscillating container densimeter that measures the temperature of the oscillating container to determine the temperature coefficient of the spring constant about the axis of oscillation.

Electronic circuit for vibrating tube densimeter

A circuit for measuring the reactance of an AC reactance sensor which varies responsive to a condition to be sensed, such as pressure, is disclosed. The circuit comprises an oscillator coupled to the sensor for providing a time varying oscillator signal having a variable frequency and a substantially constant peak to peak voltage to the sensor, and a plurality of rectifiers coupled to the oscillator and to the sensor for providing the oscillator signal as a charging signal to the sensor and for providing discharging signals from the sensor, the discharging signals being a function of the reactance of the sensor, and an amplifier coupled to the rectifiers and to the oscillator for providing an input control signal to the oscillator to control the frequency of the oscillator signal as a function of the reactance of the sensor.

Reactance measurement circuit

A circuit is coupled to an external power supply and is coupled to a non-live zero, two wire DC current transmitter (e.g. 4-20 MA output) for converting such current to a live-zero DC output current signal (e.g. 0-20 MA output) and for powering such transmitter. The circuit has a first current to voltage converter for converting the transmitter current signal to a voltage signal, and a second current to voltage converter coupled to receive the circuit output current signal and an offset current from an offset current source for converting the sum of the circuit output and offset currents to a second voltage signal. A comparator is used for comparing the first and second voltage signals to provide the live-zero output current signal representative of the non-live zero transmitter signal. The circuitry can also provide isolated power to the transmitter and feedback (closed loop) control of such power.

Growing community of inventors

Boulder, CO, United States of America

James R Ruesch