Can a cheap flowmeter be good?

April 5, 2005
Editor in Chief Walt Boyes finds that it isn’t the cost of the device but the durability that engineers are looking for. And it doesn’t have to be accurate, either, as long as it is very repeatable.
 By Walt Boyes, Editor in Chief

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 couple of months ago, I was in the company of Erik Rosaen of Flowmeters.com, I visited Fermilab (Batavia, Ill.). This Department of Energy research facility in the western suburbs of Chicago is one of the largest high-energy physics labs in the world. It is also the largest manufacturer of the world&rsquos single most expensive product.

In a hybrid continuous and batch process, Fermilab produces and stores antimatter particles called anti-protons. Its real-time process control system displays current values on the web site, as well as in its control room. As I write, Fermilab has a relatively small number (51.59 E10) of anti-protons in inventory, and the main beam is down.

Because of the highly specialized nature of the manufacturing process, Fermilab&rsquos instrumentation engineers originally built their own controllers. As you walk through the corridors, however, you can see their nearly &ldquogeological&rdquo progression from custom hardware and custom software to customized Allen-Bradley PLCs and PanelView displays, and finally to COTS (commercial, off-the-shelf) equipment from AutomationDirect.com.

The two critical control parameters are electric feed into the system, and water flow to cool the enormous set of magnets that cause the anti-protons to go where they are supposed to go. The reason Rosaen was there was that Fermilab is in the process of installing a large number of his inexpensive Coolpoint vortex-shedding cooling water flowmeters to measure this critical parameter, and he wanted to show them off to me.

The reason I was there was to ask the Fermilab engineers why they would use a &ldquocheap flowmeter&rdquo to measure a parameter so absolutely critical to their cutting-edge, and very expensive, manufacturing process. Senior engineer David Peterson said, &ldquoIt isn&rsquot the cost of the device but the durability that we&rsquore looking for. It doesn&rsquot have to be accurate, either, as long as it is very repeatable. If we lose cooling water, the process is shot, we have to dump the particles and start all over again. These flowmeters, because they have no moving parts, are very attractive from a durability point of view.&rdquo In an effort to puncture Rosaen&rsquos bubble, Peterson added, &ldquoWe&rsquove been through a lot of expensive flowmeters here, so ask us in a year how well these worked.&rdquo Click here to read my full article on Fermilab and their flow measurement application.

Traditionally, one of those &ldquoexpensive&rdquo flowmeter types has been the Coriolis mass flowmeter. Now several companies, including the biggest Coriolis vendor, Emerson Micro Motion itself, have begun offering lower cost, and even very low-cost versions, in an effort to widen the application base for the instrument. AW Company, for instance, has launched a Coriolis &ldquoprice war&rdquo by dropping the price of select sizes of mass flowmeters to below the typical pricing of magnetic and other volumetric flowmeters.

Racine Federated vice president, Tom Nelson, told me, &ldquoThe movement is toward lower cost and improved performance, all at the same time.&rdquo

I believe that Nelson is right, and these examples seem to reinforce my belief. Every time a vendor reduces the price of a process instrument, or introduces a lower overhead cost control system, it increases, sometimes tremendously, the number of processes that are now &ldquoworth measuring.&rdquo As this happens, new opportunities are created for cost avoidance, increased productivity, and even profit. This level of increased competition benefits the end user and the integrator greatly. And the vendors can make it up in volume.