Moving and measuring requires going with the flow

Moving liquids, gases, or slurries from one place to another often requires going with a flowmeter. A variety of flowmeter technologies help users with increasing demands for reliability, ease of calibration, and improved accuracy (see graphic), according to research by Control Engineering and Cahners Research (www.

By Mark T. Hoske, Editor in Chief August 1, 2001

Moving liquids, gases, or slurries from one place to another often requires going with a flowmeter. A variety of flowmeter technologies help users with increasing demands for reliability, ease of calibration, and improved accuracy (see graphic), according to research by Control Engineering and Cahners Research ( www.cahners.com ).

Among Control Engineering readers surveyed recently, the most commonly used flowmeters are magnetic, orifice, and/or turbine flowmeter types (see graphic).

For this flowmeter survey, 1,000 Control Engineering readers were sent questionnaires; 16% responded; 113 specify recommend or buy flowmeters for OEM or in-plant requirements. Raw materials processing accounted for 51%; machinery and equipment suppliers for manufacturing and service industries, 19%; and other fabricated metal and miscellaneous manufacturers, 11%. Previous reports can be found at www.controleng.com, November 2000 and March 1999.

In this survey, continuous process accounts for 60% of applications; batch, 32%; and utility services, 6%. Nearly all, 95%, respondents use flowmeters in full-pipe applications; 34% use flowmeters in open channel or partial flow pipe applications.

Among respondents, 11% bought 51-100 flowmeters in the past year; 2% bought 100-1,000 units; average was 20. Over the next 12 months, flowmeter purchases will remain steady, responses suggest.

Market breadth is significant: 42% purchased from 39 manufacturers; 50 were named in all.

Percentages represent respondents rating the feature as an important or extremelyimportant factor. Since 1999, ease of calibration and digital communications eachmoved up a spot, each surpassing the characteristic below in importance.

Who’s talking?

Communication protocols used with flowmeters now installed and with those expected to be purchased in the coming year are 90% 4-20 mA, 49% HART, and 47% 0-10 V. For purchases in the next year, respondents expect 82% 4-20 mA, 46% HART, and 41% 0-10 V. The next three protocols are gaining in use, comparing installed base to purchases expected in the next year: Ethernet 32% to 38%; Profibus-PA 12% to 18%; and FOUNDATION fieldbus 6% to 10%.

Gary Bugher, senior product manager for Flow Products at Endress+Hauser (Greenwood, Ind.), says instrument users should select the right flow measurement technology and instrument size for the application; configure and commission instruments remotely; view process variables to track trends verifying instrument performance; and analyze changes to predict maintenance. ‘The result is lower life-cycle costs due to shorter engineering time, faster commissioning, improved product quality, and less process downtime.’

Proper sizing

Vortex meter size must be selected based on the user’s flow range, and not on the process piping size, warns Don Ginesi, product manager, Flow Products, ABB Inc.’s Instrumentation Business Unit (Warminster, Pa.). ‘Pipeline vibration and hydraulic noise are always present to some degree in any process, especially steam, and are hard to quantify before installing the meter,’ Mr. Ginesi says. ‘Size vortex meters so the upper range value is equal to or greater than 0.5 times the meter’s upper range limit; and the lower range value is at least two times the meter’s lower range limit on noisy applications, like steam.’

Wade Mattar, measurement and instrumentation specialist, Foxboro/Invensys Process Systems (Foxboro, Mass.), says the most common mistake is picking meter size based on the pipe size rather than flow rates. ‘Unless the metering technology can accommodate present and future flow rates, the flowmeters will need to be sized for the rates that will be realized at start up, rather than five years down the road,’ he says.

Making an argument for a particular technology, Pete Arsuaga, ultrasonic and Coriolis flow products specialist with Krohne (Peabody, Mass.), recommends spool piece ultrasonic flowmeters for ‘fit and forget’ use. Transducers are mounted outside the flow tubes, allowing installation and replacement without needing to replace the line. Multi-beam ultrasonic flowmeters allow calculation of temperature, viscosity, and sound velocity, allowing oil types to be identified, Mr. Arsuaga says.

Omega Engineering (Stamford, Conn.) advises asking about range, accuracy, output, enclosure, and piping requirements when specifying flowmeters. These are among areas recommended in a table of questions provided at https://www.omega.com/techref/ flowtable.html .

5 best practices

Greg Livelli and Bill Graber, of Rosemount’s Vortex flowmeter area, (Eden Prairie, Minn.; Emerson Process Management) outlined five best practices to reduce capital and operating expenditures.

These best practices include:

Measuring mass flow (base volumetric) in gas and steam to reduce process variability.

Minimizing pressure loss to lower operating costs to improve capacity.

Eliminating impulse lines where possible to improve reliability, lower installed cost, and minimize maintenance.

Selecting in-line flowmeters for smaller lines and insertion flowmeters for larger lines to minimize installed cost.

Using diagnostics to enable predictive maintenance to lower operating costs.

[For more on Coriolis flowmeters, watch for coverage in November 2001 issue of Control Engineering ]

Flowmeter products

For more information on flowmeter products, circle the following numbers, or visit /freeinfo . For a wider listing of manufacturers, go to Control Engineering Buyer’s Guide at /buyersguide .

ABB vortex, swirl with DSP

Warminster, Pa.- Process vibration and hydraulic noise effects on flow range become one less thing to worry about when using ABB’s new Trio-Wirl vortex flowmeter. Advanced digital signal processing (DSP) technology have state-of-the-art filtering and vibration compensation techniques allow the electronics to find the true flow frequency within an overall sensor signal loaded with vibration/noise frequencies. There are no moving parts. Communications are digital via HART, Profibus, or FOUNDATION fieldbus protocols. www.us.abb.com

ABB Instrumentation Circle 375

Krohne UFM 500, 2-beam ultrasonic

Peabody, Mass. -Ultrasonic flowmeter technology represents a superior alternative to turbine, PD meters, and DP cell solutions, says Krohne, because of obstructionless flow design, no pressure drop, and very low maintenance. Krohne’s UFM 500 time-of-flight ultrasonic flowmeter uses a unique dual-path sensor design, enabling the flow-meter to maintain specified accuracy with highly viscous fluids and at low flow conditions. Accuracy is www.krohne.com

Krohne Circle 376

E+H Coriolis advanced diagnostics

Greenwood, Ind .; Reinach, Switzerland -Endress+Hauser’s new line of Coriolis flowmeters has a platform for advanced diagnostics. Proline Promass 80 Coriolis flowmeter (for general applications) and Promass 83 (for extended functionality) feature FieldTool, an advanced software package for configuration, setup, process visualization, and predictive maintenance. Up to four signal outputs are available to transmit measurements. FOUNDATION fieldbus, Profibus, and HART options simplify digital systems integration. www.us.endress.com

Endress+Hauser Circle 374

FlexMasster ST98 does HART

San Marcos, Calif.- Process and plant engineers who need highly accurate, repeatable flow measurement will find the FlexMasster ST98 Flowmeter Series from FCI combines superior performance with digital communications flexibility, thanks to the recent addition of HART Bus compatible electronics, the company says. Accuracy is said to be www.fluidcomponents.com

FCI Circle 377

Foxboro range

Foxboro, Mass.- Foxboro, an Invensys company, offers a range of flowmeter technologies, to meet a variety of application needs. These include E83 Series Vortex Flowmeters, I/A Series Magnetic Flowmeter with dc excitation, and I/A Series Mass Flowmeter. www.foxboro.com

Foxboro Circle 378

Omega portable doppler ultrasonic

Stamford, Conn.- FD610 Series flowmeter features advanced trans-phase measuring technology, which provides accurate and reliable flow velocity assessments in closed piping systems. FD610 Series uses a noninvasive, transducer clamped on the outside of the pipe. An LCD provides rapid, stable readings in ft/sec or m/sec. The product works with either metal or plastic pipes containing liquids with more than 100 ppm of 100-micron or larger suspended solids or entrained gases. Basic unit price is $650. www.omega.com

Omega Engineering Circle 379

Flow Technology positive displacement

Phoenix, Ariz.- Flow Technology Vector positive displacement flowmeter provides higher flow throughput and lower pressure drop than many conventional PD meters, the company says. Patented, double helical, three-lobe impeller design allows the flowmeter to be used with high- and low-viscosity liquids. With only two moving parts-the impellers-the unit is said to be easy to install and maintain. Line sizes are 1-4 in. Reference accuracy is www.ftimeters.com .

FTI Flow Technology Inc. Circle 381

Sierra Instruments for compressed air

Monterey, Calif.- Sierra Instruments’ Model 640S Compressed Air Flow Meter provides accurate mass flow measurement under varying loads, facilitating compressor audits. No moving parts, with hot-tap mounting, self-diagnostics, field-adjustability, and explosion-proof housing are among other features. It has a 2 x 12 in. LCD and can configure via an RS-232 port. www.sierrainstruments.com

Sierra Instruments Circle 380

ONLINE

Go to Control Engineering Online, back issues, August 2001 for more from several manufacturers cited here and from others.

Research flowmeter products at

See previous flowmeter research at