Ametek Land Cyclops L Series - Emissivity for 055 L, 390 L, and Reformer Tubes

11 - 3
Cyclops LPortable Thermometers
User Guide
11.3 Emissivity values for Cyclops 055L thermometers
Inordertogetatruerepresentationofthemetaltemperature,itisnecessary
tosettheemissivityvalue.Forliquidsteels,thisistypicallyintherange0.50
to0.55,butisknowntovaryslightlywithalloytypeandwillcertainlydierfor
othermetals.
Theemissivityvaluemaybesetrelativetoadipthermocoupleorother
referencemeasurementbyviewingthefreshlycleanedsurfacewhilstinthe
meltingfurnace.Theprocedureforobtainingtheemissivityvalueisveryquick
andsimpletoperform,asdescribedbelow:
1) Fromasneartotheverticalasfeasible,sighttheCyclops 055L onto the
cleansurfaceofthemoltenmetalandpressthetriggertoread.
2) Whentheinstrumentisshowingastabletemperaturevalue,obtainadip
thermocouple,orotherreferencereading.
3) Whenthetriggerisreleased,thereadingsarefrozenonthesidedisplay.
Pressthe‘select’key
togointo‘menu’mode,thenpressthe arrow
keytohighlightthe‘
e ’icon.Pressthe keytoselectthisoption.
4) Thescreenwilldisplaythecurrentemissivityvalue,togetherwiththe
mostrecentlyrecordedtemperature.Changingtheemissivityvaluewill
showthecalculatedtemperaturethatwouldhavebeendisplayedatthe
newemissivityvalue.
5) Adjusttheemissivityvalueupordownuntilthecalculatedtemperature
correspondsascloselyaspossiblewiththereferencereading.
6) Pressthe
keytoenterthenewemissivityvalue,thenpressthe key
togototheexiticonandpress toreturnto‘measure’mode.
Allsubsequentreadingswillnowusethenewlysetemissivityvalue.
11.4 Emissivity values for Cyclops 390L thermometers
Inordertoobtainaccuratetemperaturemeasurements,theemissivityvalueof
thetargetsurfacemustbeknown.
ForaCyclops 390Lsightingontocarbonsteelslabs,thetargetemissivityis
typicallybetween0.8to0.9,dependingontheexactcompositionofthesteel
andlevelofoxidation.
ContactAMETEKLandforfurtherinformation.
11.4.1 Emissivity values of Reformer Tubes
Whenmeasuringthetemperatureofreformertubes,westronglyrecommend
thatyouuseaLandGoldCupProbetoobtainaninitialaccuratetemperature
measurement,fromwhichyoucandeterminetheemissivityofyourtubes.
Atypicalemissivityvalueis0.85.AMETEKLandalsoprovideaserviceinwhich
wecananalyseasampleofyourmaterialtodeterminethepreciseemissivity.