Viscosity Testing: Do I Know Enough?

A little education on viscosity measurement is easy to come by and cangoalongwayinsolvingtheserecurringdilemmasinindustry.Brookfield Engineering, the world’s leading manufacturer of rotational viscometers,haspublishedthemostwidelyusedpamphletonviscos-ityentitled“More Solutions to Sticky Problems”. (See Figure 1) Thispublicationisavailablefreeofchargeandcananswerthequestionsraisedaboveaswellasmanyothers.ManyQCLabskeepacopyofthisdocument on the shelf and use it to train new technicians when they first startwork.

Intoday’sbusinessworld,searchingforanswersontheinternetisanotherpathtakenbymanyQCLabs.It’sasimplematterofsearchingon the word(s) that describe the problem you have, such as “pharma-ceuticalviscosity”or“viscositytesting”.Mostviscometermanufactur-ersmaintainwebsiteswithapplications

informationthatisusefulinsolvingtheeverydayquestionsthatcomeup.OntheBrookfield website (See Figure 2),thereisnotonlyanapplicationssectionwhichdescribeshowtotestvarious materials, but also a “Frequently Asked Questions” or “FAQ” section which describes how to verify that your instru-mentisreadingviscositycorrectly.

Takingaclassonviscositycanprovetobethemosthelpfulofall.Inaclassroomenvironment,youcanquicklycomeuptospeedonwhatviscosityis,howtomeasureit,

howtoknowiftheproblemiswithyourmaterialortheinstrument,etc.Brookfield, for example, provides a one-day program entitled “The Practical Course for Viscometer Operators” (See Figure 3) whichcoversthebasicswithhands-oninstructionandsendseachpersonbacktotheircompanywithhelpfulreferencematerialstosharewithothersintheQCLab.

Theabovesuggestionsarehighlyrecommendedstepswhichwillgiveyouthenecessarytoolstosolvetheeverydayproblemsthatcomeupwithviscositymeasurement.Butwhenindoubt,alwayscalltheviscometermanufacturertogetimmediatehelp.

WereceivephonecallsandemailseverydayfromcustomerswhobelievetheyarenotgettingacorrectviscosityreadingintheQCLabonmaterialthatneedstopassinspection.Insome instances, everything had been working fine until suddenly a batch of material seems to be out of specification. In another situation, the QC Lab in the USA has just received a test method for material produced in another location (perhaps Europe or Asia) and the measured viscosity values don’t agree. And sometimes, a raw material supplier simply reports that the viscosity is a certainvalue,buttheysaynothingabouthowtomakethemeasurement.Wheredoyougoforhelp?IsthereaViscosityHotLinethatcangiveaquickanswer?

Author: Robert G. McGregor, Director Global Marketing & High End Lab Instrument Sales AMETEK Brookfield, Instrumentation & Specialty Controls Division

11 Commerce Boulevard | Middleboro, MA 02346 USATel: 800.628.8139 or 508.946.6200 | Fax: 508.946.6262

www.brookfieldengineering.com

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