Micro Motion/Emerson

June 29, 2006
Technology breakthroughs soup up Coriolis flowmeter

Emerson Process Management has announced next-generation MVD (multivariable digital) technology and sensor design innovations that significantly enhance the accuracy, stability, and versatility of the company’s Micro Motion Coriolis flowmeter offering. The new technology yields breakthroughs in entrained gas measurement performance and patented self-verification technology that allow in-situ assessment of meter calibration of Micro Motion Elite Coriolis flowmeters.

The next-generation MVD technology from Emerson boosts Micro Motion Coriolis flowmeter performance to the industry’s highest-ever levels of mass flow and volume flow, and is a two-fold improvement in density performance. In addition, overall meter stability is boosted to a level that eliminates the need for field zeroing. Customers benefit directly, since flow measurement accuracy is key to operations efficiency, quality control and safety.

Previously, with +/- 0.10% accuracy, the Micro Motion Elite meter provided the most accurate Coriolis measurement available, according to the company. Now, the patented MVD technology delivers +/- 0.05% mass and volume flow accuracy, and up to +/- 0.0002 g/cc density accuracy – an improvement of two times over other Coriolis meters, Emerson asserts.

Entrained gas, also known as transient or two-phase flow, describes the flow of fluids in a pipe that shifts – by design or unintentionally – between liquid and gas, or contains both fluid states. It is a potentially problematic phenomenon for nearly any flow measurement technology, and was ranked as the key challenge for flow measurement by the NAMUR group, a German chemical industry working party of users of process automation equipment, in a recent report.

Identifying and measuring two-phase (gas and liquid) flow is difficult for flow measurement devices, often producing large metering errors or requiring an additional investment in air eliminators or flow conditioning devices. As part of next-generation Micro Motion technology, increased processing speeds and unique Coriolis sensor design are combined to solve this process dilemma, enabling accurate measurement of flows with entrained gas that include bubble flow, slug flow, and empty-full-empty batch applications.

New Micro Motion Elite flowmeters significantly improve custody transfer metering and flow measurement applications in the manufacture of such products as film emulsions, beer (wort), glucose, liquid fertilizers, soaps and lotions, hair care products, phenols, dairy products, polyethylene, well heads, and ethylene oxide.

Self-verifies its calibration and meter health

Utilizing next-generation MVD technology, the new Micro Motion Elite Coriolis flowmeters enable in-situ assessment of meter calibration and health, dramatically reducing flowmetering validation efforts and expense and enabling predictive maintenance that addresses meter health issues before they interrupt operation.

There are often application-specific reasons or industry standards that require periodic verification to ensure that flowmeters are operating properly. In quality assurance, meter verification is often a regulatory requirement; in hazardous processes, safety procedures and regulations may dictate periodic verification of otherwise perfectly functioning flow meters; in troublesome processes, meter verification can eliminate a flowmeter from the list of potentially malfunctioning devices. Micro Motion meter verification capability assesses and tracks flow tube integrity over time, enabling users to predict and plan for meter replacement when it is most convenient.

Traditionally, device diagnostics have been limited to identifying failed electronics or monitoring process conditions until off-spec product or unacceptable process variations start to erode product quality or process efficiency. Business practices required stopping the process or removing the flowmeter to verify that its performance met quality, safety or regulatory requirements. Emerson’s patented self-verification technology modernizes practices with real-time, on-demand and in-place assessment of the performance of Micro Motion Elite Coriolis meters. Further cost savings, increased plant availability, and enhanced safety and environmental compliance are achieved when the flowmeters are integrated into Emerson's PlantWeb architecture.