Brookfield KU-2 - Viscosity Units; Cleaning

Brookeld Engineering Labs., Inc. Page 8 Manual No. M04-242-E1213
I.8 Viscosity Units
 TheKrebsUnitisaspecialmeasureofviscositythatisnotbasedontheNewtonianmodelof
ow.TheASTMtestmethodD562wasoriginallydevelopedaroundthespecialconditionsofan
instrumentthatusedgravitytodriveapaddlespindleat200rpm.Theweightrequiredtoachieve
200rpmvarieddependingupontheviscosityoftheuidundertest.TheKrebsunitwasdevel-
opedthroughthecorrelationoftheweightsusedandthetimerequiredfor100revolutionsofthe
paddle.TheASTMstandardalsoprovidedacorrelationfromKrebsUnitstothescienticmeasure
ofviscosityincentipoise.
 TheGramsscalerepresentstheweightrequiredtodrivethepaddlethroughthetestuidatarate
of200rpm.ThegravitydrivesystemspeciedinASTMD562requiredthattheweightbevaried
until100revolutionswereachievedin30seconds(200rpm).TheKU-2drivestheunitat200rpm
automaticallyandprovidesthegramsvaluethatwouldberequiredonthegravitydrivesystem.
Thegramsscaleisnotaviscosityunit.
 TheCentipoisescaleisavailablethroughacorrelationoriginallydenedintheASTMtestmethod.
SincethisvalueisbasedontheKrebsUnit,itisnotequivalenttocentipoisevaluesdeterminedusing
othertypesofviscometers,suchastheBrookeldRVDV-I+.Thecentipoisevaluesdisplayedon
theKU-2areforreferenceonly.Comparisonstomeasuredvaluesfromotherinstrumentsshould
notbemade.
I.9 Cleaning
Makesuretheinstrumentisinadecentworkingenvironment(dust-free,moderate
temperature,lowhumidity,etc.).
Makesuretheinstrumentisonalevelsurface.
Hands/ngersmustbecleanandfreeofresiduesample.Notdoingsomayresultin
depositbuildupontheupperpartoftheshaftandcauseinterferencebetweentheshaft
andthepivotcup.
Besuretoremovethespindlefromtheinstrumentpriortocleaning.Noteleft-handed
thread.Severeinstrumentdamagemayresultifthespindleiscleanedinplace.
InstrumentandKeypad: Cleanwithadry,non-abrasivecloth.Donotusesolvents
or cleaners.
ImmersedComponents(spindles): Spindlesaremadeofstainlesssteel.Cleanwithanon-
abrasiveclothandsolventappropriateforsamplematerial.
Whencleaning,donotapplyexcessiveforce,whichmayresultinbendingspindles.