Hot Topics

Your Flow and Temperature Industry Monitor

Flow Research, 27 Water Street, Wakefield, Massachusetts 01880                                                            ISSN: 1530-7204

Volume 2, Number 1                                                                                 January-February 2001


What Users Want in Infrared Products

As part of our worldwide infrared study, Flow Research and Ducker Research conducted a detailed survey of 100 users of infrared products.  One question we asked users was “What are the features of the ideal infrared thermometer?” and The purpose of the question was to get an understanding of what features are most important to users, especially when they are thinking about purchasing infrared products.


Table 1 gives the answers we received.  One of the most interesting features of this table is that accuracy and reliability are the two most-mentioned features.  Accuracy and reliability are also the top two criteria mentioned by users of flowmeters as being most important when they are selecting flowmeters.  Apparently the twin criteria of accuracy and reliability are important to users of different types of instrumentation.


Why is accuracy so important?  Obviously, users want to believe that the temperature value being given to them by their infrared thermometers corresponds to the actual temperature.  One reason this is important for infrared thermometers is due to the role of emissivity in measurement.  Emissivity is the ratio of the heat or radiant energy that is emitted by an object at a specific temperature to the heat or radiant energy emitted by a blackbody at the same temperature.  A blackbody is an ideal material that absorbs all radiation or heat energy, and does not reflect any.  Emissivity values are always between 0.0 and 1.0.


We also asked users if they take emissivity into account when making infrared measurements.  In response, 47 percent say yes, while 53 percent say no.  This suggests that some users are unaware of the importance of emissivity, or they assume that their infrared thermometers automatically take emissivity into account when making a reading.  Emissivity is important to accuracy in the reading of an infrared thermometer, and if it is not taken into account, the reading may be inaccurate.


We also asked users about their suggestions to infrared suppliers for improving service.  Training was the most-mentioned suggestion, and knowledgeable representatives was the second-most mentioned suggestion.  What all this data suggests is that there is a substantial need and desire for training of endusers of infrared products.  Suppliers who want to distinguish themselves from their competitors can fill this need in several ways:


·        By offering technical and explanatory material on their websites

·        By providing videos and CDs that explain how to use their products

·        By offering training courses in the use of infrared products

·        By educating their sales and service reps so they can answer questions better


Table 1.  Features of the Ideal Infrared Thermometer





Accuracy of reading


Measuring quantities


Reliability of product


Measuring temperatures


Easy to use


Spot size




Focal length


Cost effective


Wave length




Display units








Downloadable on PC




Self contained




Larger ranges




Better storage


Digital readout


Able to adjust




One button operation


Quality of display


Better readings




Works well


Data input RS232 of reading


No calibration




Ease of maintenance


Manual & electronic set up


Beam for distance






More intelligence and data storage


Heavy duty


Ability to withstand high temperatures


Hold up in any environment




Full scope of service


Broad range




Unlimited local length


Comfortable size




Water resistant


Full range


More distance




Able to see through fog or vapor


Wide range of temperature




Total Respondents


A Paradigm Case Flowmeter Selection Method

By Jesse Yoder


Anyone who buys or specifies a flowmeter has to make a decision about what type of flowmeter to select.  While various attempts have been made to formulate a method for selecting flowmeters, there is no industry-wide consensus on how this should be done.  This article presents an overview of a paradigm case flowmeter selection method.


The paradigm case method depends on the fact that every flowmeter is better suited for some applications than others.  For example, Coriolis meters are best suited to measuring fluids in pipes from six inches in diameter and less.  Thermal meters are most widely used to measure gases.  Magnetic flowmeters require that the liquids they measure be conductive.  Each type of flowmeter has its limits, and also has those applications it is well suited for.


The idea behind the paradigm case method is that each type of flowmeter has a set of applications it is ideally suited for.  This is the paradigm case for that type of flowmeter.  For example, the paradigm case application for ultrasonic flowmeters is clean, swirl-free liquids and gases of known profile.  Table 2 gives paradigm case applications for new technology meters.

Table 3.  Paradigm Case Conditions for New Technology Flowmeters

Type of Flowmeter

Paradigm Case Conditions



Clean liquids and gases flowing fast enough to operate the meter and flowing through pipes of size six inches or less. 

Some provide density measurement; Measure mass flow directly


Conductive liquids flowing through a full pipe that do not contain materials that coat the electrodes or damage the liner

Cannot be used to measure gas or steam

Ultrasonic – Transit Time

Clean, swirl-free gases and liquids of known profile

A multipath meter may be required for high accuracy


Clean, swirl-free, low viscosity, medium to high-speed fluids.

Work for liquids, steam, and gas


The following is an abbreviated statement of the steps involved in the paradigm case method.


1.      Every type of flowmeter is based on a physical principle that correlates flow with some set of conditions.  This principle determines the paradigm case application for this type of flowmeter.  When selecting a flowmeter, begin by selecting the types of flowmeters whose paradigm case applications are close to your own.


2.      Make a list of application criteria (e.g., pipe size, process pressure, Reynold’s number, etc.) that relate to the flow measurement you wish to make.  From those types of flowmeters selected in step 1, select those that meet these application criteria.


3.      Make a list of performance criteria (e.g., accuracy, reliability, etc.) that apply to the flowmeter you wish to select.  From those types of flowmeters selected in step 2, select the ones that meet these performance criteria.


4.      Make a list of cost criteria (cost of ownership, installation cost, etc.) that apply to your flowmeter selection.  From those types of flowmeters selected in step 3, select the ones that meet these cost criteria.


5.      Make a list of supplier criteria (e.g., service, training, etc.) that govern your selection of a flowmeter supplier.  From the types of flowmeters listed in step 4, select the suppliers that meet your criteria.


6.      For the final step, review the meters that are left as a result of step 4 and the suppliers listed as a result of step 5.  Review the application, performance, and cost conditions for the remaining flowmeter types, and select the one that best meets all these conditions.  Now select the best supplier for this flowmeter from those listed as a result of step 5.


NOTE: Some of the above material is taken from an upcoming article in the February 2001 issue of Control Magazine on New Technology Flowmeters and How to Select Them.  We welcome comments on either article.


A Preview of Upcoming Worldwide Flowmeter Studies

Flow Research is currently conducting a study of the worldwide flowmeter market.  This study will be done in two phases.  Phase One includes “new technology” flowmeters:

·        Coriolis

·        Differential pressure

·        Magnetic

·        Ultrasonic

·        Vortex. 


The new technology study is nearly complete, and will be available in March 2001.  It includes market size, market shares, flowmeter technology and product analysis, strategies for success, and company profiles.  Geographic regions include North America, Europe, Japan, Asia without Japan, and Rest of World.  This promises to be a landmark study.


Phase Two includes the traditional technologies


·        Open channel

·        Positive displacement

·        Thermal

·        Turbine

·        Variable area


Phase Two will include the same features and the same geographic breakdown as Phase One.  It has been a long time since a complete market study has been done on these types of flowmeters.


At the same time Flow Research and Ducker Worldwide are conducting a worldwide survey of flowmeter users.  This end-user survey will be available separately from the supplier studies.  For this survey, we are interviewing 100 flowmeter users from each of the world’s major geographic regions: North America, Europe, and Asia.  The interviews from North America are already complete, and analysis is currently underway.  The European interviews are underway, and the Asian calls will be begin shortly.  The European and Asian interviews are being conducted in the native languages.


When this extensive enduser survey is complete, we will have a total of 300 telephone interviews from flowmeter users worldwide.  This will be a comprehensive body of data that is unprecedented in terms of today’s market research.  There will be a separate analysis of data from each geographic region, and a total worldwide analysis.  The projected completion date for the worldwide enduser study is April 2001.  Stay tuned to for updates on the availability of all three worldwide flowmeter studies.  Contact us if you have any questions about these studies.


Join our Flowlist!

Flow Research has established a free bulletin board service to encourage discussion of temperature, flow, pressure, and related topics.  The service is called Flowlist.  To subscribe, go to our website at and click on Flowlist.  Flowlist contains both members of supplier and end-user companies.  Once you join, feel free to submit any topics you’d like to discuss to the Flowlist.  Your email will automatically go to all members.


Just Released: Worldwide Infrared Study

Flow Research has just completed a study of the worldwide infrared market.  This study includes infrared thermometers, linescanners, thermal imagers, and firefighting cameras.  The study contains detailed and extensive market size analysis of the following products:

·        Infrared thermometers: Portable and fixed, general purpose and specialized

·        Linescanners: General purpose and specialized

·        Thermal imagers: Portable and fixed, general purpose and specialized

·        Firefighting cameras: Handheld and helmeted


The following five geographic regions are included: North America, Europe, Japan, Asia without Japan, and Rest of World.  Suppliers worldwide were interviewed for this study, including Raytek, FLIR Systems, Land Instruments, Ircon, ISG, Marconi, Chino, Cairns, Heitronics, and many others.  For more information on this study, which includes an extensive survey of end-users of infrared products, contact Flow Research at 781-245-3200, or


Also Available: Temperature Sensor and Transmitter Study

The Market for Temperature Sensors and Transmitters in the Americas has received wide circulation among temperature sensor and transmitter suppliers.  If you haven’t yet ordered your copy of this landmark study, there is still time to do so.  Visit our website at for complete information on the study, or contact Flow Research at 781-245-3200.  You can also send an email to for complete information.


Hot Topics is published by Flow Research, 27 Water Street, Wakefield, MA  01880.

(781) 245-3200 (phone) (781) 224-7552 (fax)            Copyright © 2001 by Flow Research

Editor: Jesse Yoder, PhD                              Research Assistant: Kelly Deppen                       

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