Carbolite CAF DIGITAL IMAGING Assembly instructions

MF36-3.05
Installation, Operating &
Maintenance Instructions
CoalAshFusionTestFurnace
CAFDIGITALIMAGING
This manualis fortheguidance ofoperators oftheCAFDigitalfurnace andshould beread
before thefurnace is connected to theelectricityand gas supplies. Itcontains information
required forsafeand trouble-freefurnaceoperation. If, however, anyquestions remain
unanswered pleasecontactourservicedivision attheaddress attheend ofthis manual.

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CONTENTS.
page
1.0 SafetyInformation. 4
1.1 General.4
1.2 Carbon MonoxideWarning.4
1.3 Hydrogen And Carbon DioxideWarning.5
1.4 RefractoryFibrous Insulation Warning.5
1.5 Viton ‘O’ ringSeals Warning 6
2.0 Models CoveredByThis Manual.6
3.0 Installation Instructions. 7
3.1 UnpackingAnd Handling.7
3.2 PackingList.7
3.3 AssemblyOfTheFurnace.7
3.4 PositioningTheFurnace.10
3.5 ElectricalConnections. 10
3.6 VoltageLevel&PowerLimit Settings11
3.7 ExhaustVentConnections. 11
3.8 Gas Connection.12
3.9 Camera Mounting&Connections – StandardLens13
3.10 Camera Mounting&Connections – ZoomLens13
3.11 Computer Connections. 14
4.0 OperatingInstructions. 15
4.1 Furnace Start-Up.15
4.2 EurothermController15
4.3 Computer Start-Up. 15
4.4 LoadingSamplesInto TheWork Tube.16
4.5 RunningACoalAsh Fusion (CAF)Test.17
5.0 Maintenance and Calibration. 22
5.1 GeneralMaintenance.22
5.2 ElementAgeing.22
5.3 CheckingAnd Replacing TheDoor‘O’ RingSeal.22
5.4 CleaningTheViewingWindow.22
5.5 Furnace Calibration.23
6.0 Circuit Diagrams.27
7.0 Fault Analysis.28
8.0 After Sales Service.29
8.1 Recommended Spares And Consumables. 29
9.0 Specifications.30

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10.0 Appendix.31 -end
Fig1.Elementwiringand positions.
Fig2.Work tubeand back plug assembly.
Fig3.Fronttubesealassembly.
Fig4.Doorarmassembly.
Fig5a.Camera mountingbracket.
Fig5b.Standard lens &camera assembly.
Fig5c.Slidingthecameramountingbracketassemblyonto thedoorarm.
Fig5d.Securingthecamera mountingbracketassemblyto thedoorarm.
Fig5e.Mountingthestandard lens &camera assembly.
Fig5f.Standard lens &camera assemblyin position.
Fig5g.Zoomlens assembly&lens clamp.
Fig5h.Fittingthecamerato thezoomlens.
Fig5j.Mountingthelens heatshield.
Fig5k.Mountingthezoomlens &bracketassembly.
Fig5l.Zoomlens in position.
Fig5m.Adjustingtheposition ofthezoomlens &camera assembly.
Fig5n.Releasinglens clamp screwto rotatecamera&lens assembly.
Fig5p.Storingthezoomlens &carrier.
Fig6.Rear viewoffurnace showingbrick boxassembly.
Fig7.Fronttubesealposition.
Fig8.Tubeend sealassemblytighteningsequence.
Fig9.Work tubefrontsupport.
Fig10.Fittingthedoorarmassembly.
Fig10a.Adjustingthedoorarmassembly.
Fig11.Furnace caseand controls.
Fig12.Positioningthefurnace.
Fig13a.Positioningsamples on thesamplecarrier.
Fig13b.Loadingsamples into thework tube.
Fig13c.Loadingsamples into thework tube.
Fig14.Set-up options.
Fig15a.Filenameand sampleidentifier.
Fig16.Filedirectory.
Fig17.Doorarmassemblyexploded view.
Fig18.Reportsheet.
Fig19.Formed wiresample.
Fig20.Samplecarrier, sampletiles and samplepositions.
Fig21.Routeofcameravideo cables.

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1.0 SAFETY INFORMATION.
1.1 General.
Pleaseread all ofthis section first.
Pleaselook through thecompletemanualbefore connectingthefurnace.In
particular read through thesection on installation and observesection 3.6
aboutsupplyvoltage.
This furnacemustbeearthed (grounded).
Do notoperatethefurnaceattemperatures above815°C(1500°F)with thedooropen.
Thefurnace doormustnotbeleftopen longer than is necessaryto loadand unload samples from
thework tube.
Thefurnace doormustbeclosed and secured usingthetwo swingbolts before commencinga
CoalAsh Fusion test.Itis importantthattheswingbolts aretightened evenlyto createagas tight
sealbetween thedoorflanges. When acoalash fusion testis runningtheyellowTestIn Progress
lightilluminates on thecontrolpaneland thegreen StandbyModelightgoes out. Do notopen
thefurnace doorwhen theTestIn Progress lightis illuminated orexposure to carbon monoxide
mayresult. See section 1.2:Carbon MonoxideWarning.
DuringatestonlytheyellowTestIn Progress lightshould beilluminated. Ifanyoftheother
three lightsare illuminated (see fig11)then thereis afault: do notuse thefurnaceuntil thefault
is rectified.
DuringStandbyModeonlythegreen StandbyModelightshould beilluminated. Ifthere are no
lights illuminated, orifanyoftheother threelights are illuminated (seefig11)includingthe
green StandbyModelight, then there is afault: do notuse thefurnaceuntil thefault is rectified.
Do notoperatethefurnacewith thedoororwindow‘O’ ringseals removedorexposure to
carbon monoxidemayresult. See section 1.2:Carbon MonoxideWarning.
Aregular work tubepressure testmustbeconducted to ensure integrityofthework tubeand ‘O’
ringseals. See section 3.3.5:Pressure testingoftheWork TubeAssembly.
To avoid fire, do notexposecombustiblematerials to heatfromtheopen door.
Do notusethefurnace inthepresence ofinflammableorcombustiblechemicals:fire or
explosion mayresult. Do notplace thefurnaceon an inflammablesurface.
When operatingthefurnace wear appropriatesafetyclothing, includingeyeprotection and
gloves.
Isolatethefurnacefromtheelectricaland gas supplyand ensure thatthefurnace iscold before
changingelements, thermocouples orundertakingother routinemaintenance.
1.2 CarbonMonoxideWarning.
Operation oftheCAFDigitalfurnaceinvolves theuseofcarbon monoxide.
When testingin accordance with ASTM:D1857-87 (1994)Carbon
monoxideisintroduced as a‘reducing’atmospheregas and carbon
monoxideis produced as aby-productwhen testingin accordance with
BS1016:Part113:1995 ISO540:1995 and ASTM:D1857-87 (1994).
Carbon monoxide(CO) is acolourless, odourless, tasteless and inflammable
gaswhich is acutelytoxic. COis introduced into theblood streamthroughthelungs and binds
with thehaemoglobin preventingit fromcarrying oxygenaround thebody.This can result in
rapid damageto bodytissues dueto oxygen starvation. Since COis an accumulatingtoxin it can
bedangerous even whenpresentin quitelowconcentrations over longperiods oftime.
Individuals varyconsiderablyin theirreactions to concentrations oftoxicgases;table1 shows
thetypicaleffects ofcumulativeCOexposure.

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To minimisetherisks associated with COit is mostimportantthatthefurnace is installed and
operated in accordancewith this instruction manual.Ifthefurnace operatorexperiences anyof
theeffects listed above, thefurnace mustbeisolated fromthegasand electricitysupplies
immediatelyand expertadvice sought. Forsafetyguidelines seek thegas manufacturersadvice.
Table1. Carbon monoxidein air:
Information extracted fromGuidance NoteEH43 (1996)fromtheHealth and SafetyExecutive.
Partsper
million Effect.
50 Recommended Exposure Limit (8 hours time weighted average concentration).
200 Headache afterabout7 hours ifrestingorafter2 hoursexertion.
400 Headache with discomfortwith possibilityofcollapse after2 hoursatrestor45
minutesexertion.
1200 Palpitationsafter30 minutesatrestor10 minutesexertion.
2000 Unconsciousafter30 minutesatrestorup to 10 minutesexertion.
Forfurther information refer to:
-Guidance NoteEH43 (1996)fromtheHealth and SafetyExecutive. ISBN0 11 883597 1
-EH40/97 OccupationalExposureLimits 1997. ISBN0 7176 1315 1
1.3 Hydrogenand CarbonDioxideWarning.
Applicablefor furnaces constructed to useH2and CO2testgases withCO2
‘Purge’ gas.
H
2
can formexplosivegas mixtures, takeprecautions to avoid leakageof
H2. H2and CO2can reactto formCO. See section 1.2:Carbon Monoxide
Warning.
Carbon dioxide(CO2)isacolourless, odourless and tasteless gas thatis an
asphyxiant. Rapid unconsciousness occursatlevels above11%, levels of20 -30%are
immediatelyhazardous to life.
Information extracted fromCroner Publications Ltd. Substances Hazardous To Health.
To minimisetherisks associated with CO2it is mostimportantthatthefurnace is installed and
operated in accordancewith this instruction manual.Ifthefurnace operatorexperiences anyof
theeffects listed above, thefurnace mustbeisolated fromthegasand electricitysupplies
immediatelyand expertadvice sought. Forsafetyguidelines seek thegas
manufacturers advice.
1.4 RefractoryFibrous InsulationWarning.
This furnacecontains refractoryfibres in its thermalinsulation. These
materials maybein theformoffibre blanketorfelt, vacuumformed board
orshapes, mineralwoolslab orloosefill fibre.
Normaluseofthefurnacedoes notresult in anysignificantlevelof
airbornedustfromthesematerials, butmuch higher levels maybe
encountered duringmaintenance orrepair.
Whilstthere is no evidence ofanylongtermhealth hazards, westronglyrecommend thatsafety
precautions are taken whenever thematerialsare handled:
Exposureto dustfromfibrethathas beenused athightemperatures maycauserespiratory
disease.
Whenhandling fibrealways useanapproved mask, eye protection, gloves and long sleeved
clothing.
Avoid breaking up wastematerial. Disposeofwastefibreinsealed containers.
After handlingrinseexposed skinwith water beforewashing gentlywithsoap (notdetergent).
Washwork clothing separately.

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Before commencinganymajorrepairswerecommend reference to theEuropean CeramicFibre
IndustryAssociation Bulletin No. 11 and theUK Health and SafetyExecutiveGuidance Note
EH46. Wecan providefurther information on request, alternativelyourservice division can
quoteforanyrepairs to becarried outatyourpremises orours.
1.5 Viton‘O’ring Seals -Warning.
The‘O’ ringseals used in theCAFDigitalfurnacework tubeassemblyare
manufactured fromViton. Viton is combustibleand decomposition occurs
atelevated temperatures. Decomposition products includeHydrogen
Fluoride, fluorinated hydrocarbons, Carbon Monoxideand Carbonyl
Fluoride. Hydrogen Fluorideis highlycorrosive.
Although theseseals should notbeexposed to elevated temperatures
duringnormaluse, thefollowingprecautions should betaken:
· Wear neoprenegloves whilehandlingtheseals.
· Disposeaccordingto localregulations. Landfill is recommend. Burningisnotrecommended
exceptbyanapproved orlicensed incineration agent.
2.0 MODELS COVEREDBY THIS MANUAL.
Two basicfurnaceoptions are available, which differ onlyin thegases usedto createthe
‘oxidising’and ‘reducing’atmosphere and thecontrolofthosegases.
Option 1. CO/CO2‘reducing’gas and Air‘oxidising’gas with N2‘Purge’ gas.
Compatiblewith -ASTM D1857-87 Standard TestMethod forFusibilityofCoal
and CokeAsh.
Option 2. H
2
and CO2‘reducing’gases and CO2‘oxidising’gaswith CO2‘Purge’ gas.
Compatiblewith -BS1016 :Part113 :1995 ISO540 :1995 Methods for
Analysis and TestingofCoaland Coke. Part113. Determination ofAsh
Fusibility.

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3.0 INSTALLATION INSTRUCTIONS.
Thefurnace contains electricalparts and should bestored and used in indoorconditions as
follows:
temperature:5°C-40°C
relativehumidity:maximum80%up to 31°Cdecreasinglinearlyto50%at40°C
3.1 Unpacking &Handling.
This furnaceis heavy, takeappropriateprecautions when liftingormovingit and useasufficient
number ofpeople.
When unpackingormovingthefurnace always liftit byits base. Never liftitbyanyattachments
orprotrudingparts. Avoid applyingforce to internalcomponents such as thework tubeor
insulation.
3.2 Packing List.
Thepackagingshouldcontain thefollowingcomponents:
1 off Furnace assembly.
1 offWork tubeand back sealassembly, see fig2.
1 offWork tubefrontinsulatingcollar.
1 offWork tubegasket.
1 offFronttubesealassembly,see fig3.
1 offDoorarmassembly(withoutdoorplug), see fig4.
1 offDoorplug, see fig4.
1 offFlexiblegas pipe.
1 offCamera mountingbracket, see fig5a.
1 offStandard lens and cameraassembly, see fig5b.
1 offZoomlens assemblyand lens clamp, see fig5g. if supplied
1 offZoomlens mountingbracket.if supplied
6 offPanelholeblankingplugs.
5 offCableties.
1 offSampleCarrier.
100 offSampletiles.
1 offSampleloadingtool.
1 off‘Windowretainingring’spanner.
1 offConemould.
1 off 150mm length ofGold wire (1063°Cfusewire).
1 off150mm length ofPalladiumwire (1554°Cfusewire).
1 offCarbon Monoxidemonitor.
1 offRS 232 Interfacecable.
1 offCamera videoextension cable.
1 offComputer.
1 off Monitor.
1 offKeyboard.
1 offMouse.
1 offCarbolitesoftware protection dongle.
2 offComputer power cables.
1 offSet-Troubleshootingdiscs.
1 offSet-Computer operating instructions.
1 offInstallation, Operating&Maintenance Instructions fortheCAFTestFurnace.

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3.3. Assembly OfTheFurnace.
3.3.1. ElementFitting.
Ensure thatthefurnaceis isolated fromthemains supply. Removethebackpanelfromthe
furnaceunit.
Note:Theheatingelements are fitted atthefactoryto testthefurnacebutare removed fortransit.
Theseelements are extremelyfragile, and can bedamaged bycontamination:handlethemwith
care and keep themclean. Avoid touchingtheheatingpart.
Slideoneinsulatingcollarover eachelement, thengentlyslidetheelementinto its holein the
furnaceuntil thetip oftheelementlocates in thefrontinsulation, see fig1. Iftheelementdoes
notslidein freelycheck thatyou are holdingit in linewith thehole;it mayhelp to rotatethe
elementwhilstslidingit in. Onlylightfinger pressure should berequired. When theelementis in
position slidetheinsulatingcollarup againstthefurnace back insulation.
Usethebraids to link theelements and connectthemto theterminalposts as shown in fig1.
Makesure thebraids do nottouch anyother component, oreach other.
3.3.2. InstallingTheWorkTubeAnd RearSealAssembly
Ensure thatthefurnaceis isolated fromthemains supply, removethebackpaneland frontpanel
fromthefurnace unit.
Removethefixingnutand onewasherfromeachofthework tubeback supportfixingpillars on
theback ofthefurnace. See fig6.
Carefullyinserttheworktubeand back sealassemblyinto thefurnace fromtheback and slideit
through thefurnace until thework tubeis protrudingfromthefront. Thework tubeis correctly
positioned when:thework tubeinsulatingcollar isin contactwith thebackface ofthefurnace
heatingchamber, thework tubeback supportis located overthefixingposts and the
thermocouplesheath is atthetop abovetheventtubefitting. Secure thework tubeback support
in position usingthefixings provided. Seefig6.
Note:Takecarenotto stress thework tube. Thework tubeback supportmustbeparallelto the
back ofthefurnace heatingchamber and it should notbenecessaryto bendtheback support
fixingposts to locateit.
Connectthenumbered thermocoupleleads to thethermocoupleconnectingterminals mounted on
thework tubeback support. Ensure correctpolarity, thenegativelegs ofthethermocoupleare
marked blue, compensatingcablecolourcodingis:Negative=white. Positive=orange.
Makesure theelementbraids do nottouch anymetalcomponents oftheback tubesealassembly.
3.3.3. Fitting TheWorkTubeFrontSealAssembly.
Slidethework tubefrontinsulatingcollar over thefrontprotrudingpartofthework tubeuntil it
is in contactwith thefrontface oftheheatingchamber.
Dismantlethefronttubesealassemblybyremovingthesixsocketscrews. See fig3.
Slidethework tuberingover thefrontofthework tubewith theinternalchamfer facingtowards
thefront. See fig7.
Fit thetube‘O’ ringoverthefrontofthework tubeand position it uniformly7.0mm fromthe
frontedgeofthework tube. See fig7.
Fit thework tubegasketto thework tubesealingringasfig7, position thework tubesealingring
on thefrontend ofthework tubeand looselysecure to thework tuberingusingthesixsocket
screws provided.
Rotatethefrontsealassemblyso thattheswingbolts are positioned horizontallyand thegas inlet
fixingis atthelower leftsideofthework tube. Seefig8.

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Tighten thesixsocketscrews evenlyin thesequence as shown bynumbers1 to 6 in fig8. Ensure
thatthework tubesealingringis held firmlyagainsttheend ofthework tubeand is evenly
spaced fromthework tuberingaboutits circumference.
Fit thefurnace frontpanelin position and adjustthework tubefrontsupportbracketto support
theweightofthework tubeassembly. See fig9.
Note: Do notstress thework tube. With thework tubefrontsupportcorrectlyadjusted there
should beaslightgaparound thecircumference ofthetubewithin theaperture ofthefurnace
heatingchamber. This can betested forbyliftingthework tubeupwards fromthesupport
bracket, onlyaslightgapshould beobserved between thework tubeand thesupportbracket
when thework tubeis lifted as far as possible.
3.3.4. Fitting And Adjusting TheDoorArmAssembly.
Note: therefractorydoorplugis fragile:handlewith care.
Thedoorplugis supplied separatefromthedoorarmassemblyto avoid transit damage.Fit the
doorplugto thedoorarmassemblybefore fittingthedoorassemblyto thefurnace. Refer to
section 5.4.
Pull outthedoorslideshaftto its full extension and rotateit fullyanti clockwise(viewfrom
front). Thedoorslideshaftwill onlyrotatewhen it is fullyextended.
Removethefoursocketscrewsfromtheback ofthedoorarmassemblymountingblock only;do
notremovethefrontfixingscrews, which arefactorysetto position thedoorarm. See fig10a.
Slidethedoorarmassemblyonto theend ofthedoorslideshaftand securefirmlyin thedoor
open position shown in fig10. usingthefoursocketscrews. Takecareto tighten thesocket
screwsevenlyto avoid anydistortion in thedoorarmassembly.
Caution: To allowthedoorsideshaftto slidein and out, someclearanceis required in thedoor
mechanism; consequentlythereis asmall radialmovementin thedoorslidearmwhen thedoor
armis pushed in towardsthework tube.Becauseofthis radialmovementit is possibleforthe
doorplugto contactthework tubefrontsealassemblyifthedoorhandleis lifted as thedoorarm
is pushed inwards:takecare to avoid this happening.
Carefullyswingthedoorarmin aclockwisedirection (viewfromfront)to its stop position,
ensuringthatthedoorplugdoes nottouch tubeend guard. Thedoorplugshould beclear ofthe
furnacein its fullywithdrawn position. Itshould notbepossibleto push thedoorarmin towards
thefurnace until thedoorarmis rotated fullyclockwise(viewfromfront)and thedoorplugis in
linewith thework tubefrontaperture.
Attached to thedoorarmassemblyis aconduit carryingthevideo and power cables forthe
camera. Pass thewires through theconduit plateaperture in theleft-hand sideofthefurnacecase
and connectthecamera power cableconnectorsituated justinsidetheconduit plateaperture.
Routethecameravideo cableas shown in fig. 21 and tieinto theexistingwiringatsuitable
points usingthecableties provided.
Note: takecare to routethecableawayfromsharp edges and hotsurfaces.
Fit thecamera videocablephono socketinto theholeadjacentto thecomms socketin thebottom
flangeattherearofthefurnace case. Secureusingthefixings provided.
Fit thefurnace casebackpanel.
Carefullyslidethedoorpluginto thework tubeensuringthatit is clearofthefrontseal
assembly.Ifthedoorplugis misaligned, adjustmentofits position in relation to thework tube
can beachieved byslackeningthefrontand backdoorarmfixingscrews and rotatingthedoor
armaboutthedoorslideshaftaxis. See fig10a.
3.3.5. Pressure Testing oftheWorkTubeAssembly.
Note: To ensure thatthework tubeassemblyhasbeen correctlyinstalled itis necessaryto
pressure testthefurnace priorto use.

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Dueto thehighwork tubetemperatures used duringCAFtestingthetube‘O’ ringseals will
deterioratewith time. Thefurnace work tubealso has afinitelife and mayeventuallycrack due
to normalwear and tear.Itis necessarytoconductapressuretestofthework tubeassemblyat
regular intervals duringnormaluseofthefurnaceto ensure integrityofthework tubeand ‘O’
ringseals. Thefollowing procedureapplies:
Connectoneend oftheflexiblegas inletpipe(normallyconnected betweenthebulkhead
connection on thefrontofthefurnace caseand thework tubefrontsealassembly)to thework
tubefrontsealassembly.See fig11. Connecttheother end to an adjustablecompressed airtest
lineorinertgas supplycapableofdeliveringup to 4 psi. Check all air/gasconnections forleaks,
anyleakagefromtheair/gas supplylinemayaffectthepressure testresults.
Closethedoorassemblyand clamp in position usingtheswingbolts.
Securelyblock theworktubeventattheback ofthefurnace usingabungorblankingplug.
Pressurisethework tubeassemblyviatheflexiblegas inletpipeto 3 psi ±1psiusing
compressed airorinertgas, and check thatthework tubeassemblydoes notleak.
Followingsuccessfulpressure testingoftheworktubeassembly,connecttheflexiblegas inlet
pipeto thebulkhead connection on thefrontofthefurnace case. Check all externalgas
connections and venttubes forleaks priorto using thefurnace.
3.4. Positioning TheFurnace.
Significantamounts ofcarbon monoxidemaybeexhausted fromthework
tubeduringtheuseofthis furnace. Carbon monoxideis toxicand
inflammable(see section1.2:Carbon MonoxideWarning.)and mustbe
ducted outofthebuilding. See also section 3.6:ExhaustVentConnections.
Thefurnace is designed to begas tightduringnormaloperation, butincorrect
installation orcomponentfailures dueto misuseorwear and tearcouldgive
riseto ahigh presence ofcarbon monoxide. To minimiserisk to theuser in
theeventofahigh presence ofcarbon monoxidethefurnace mustbeinstalled under asuitable
forcedairextraction hood. An exampleis shown in fig12. Theextraction hood mustbeducted
outofthebuildingand mustbeoperatingwheneverthefurnace is in use. Theroommustbewell
ventilated and the‘fresh airin’ventilation should exceed thehood extraction to ensure that
fumes do notescapeinto theroom.
As aprecaution thefurnace is supplied with acarbon monoxidedetector.IftheCOdetectoris
correctlyinstalled it will alertthefurnaceoperatorin theeventofaleak ofcarbon monoxidethat
is notremoved byextraction.
Note: TheCOdetectormustbepositioned and installed in accordance with themanufacturer’s
instructions supplied. In theeventofaCOdetectoralarmevacuatetheareaimmediatelyand
seek expertadvice.Isolated thefurnace fromthegas and electricitysupplyonlyifit is safe to do
so.
Ensure thatthefurnaceis installed in such awaythattheelectricalsupplyand thegas supplycan
bequicklyswitched off in theeventofanemergencywithoutanydanger to theoperator.
Ensure thatthereis aminimumfree spaceof100mmaround thefurnace anddo notobstructany
ofthevents in thecaseasthesearerequired to keep internalcomponents cool.
3.5. ElectricalConnections. Connection bya qualified electrician is recommended.
Thevoltageorrangeofvoltages on which thefurnace maybeoperated isgiven on thefurnace
ratinglabel. See fig11. Check thatthesupplyvoltageis compatiblewith thevoltageon thelabel,
and thatthecurrentcapacityis sufficientforthemaximumcurrenton thelabelbeforeconnection
to thesupply.
Thefurnace should bepermanentlyconnected to thecorrectsupplythrough awall mounted
isolatingswitch oraneasilyremovableplug.Theswitch orplugshould bewithin easyreach of