HALDENWANGER Ceramics for KilnsComponents having higher thermal shock resistance allowing increased...
Transcript of HALDENWANGER Ceramics for KilnsComponents having higher thermal shock resistance allowing increased...
Ceramics for KilnsHALDENWANGER
HALDENWANGER
CONTENTS
2
SIGNIFICANCE of ceramics for kiln construction and furniture
SUMMARY of our ceramic materials
INSULATION COMPOUNDS
REFRACTORY CEMENTS
Physical PROPERTIES
CERAMIC TUBES Selection from our production programme
TOLERANCES according to DIN 40680
EXAMPLES OF APPLICATIONS for ceramic materials
CERAMIC ROLLERS
EXAMPLES OF APPLICATIONS for ceramic components
SIZES of muffles, open both ends
TECHNICAL CERAMICS
Optimised utilisation of energy: The short thermal cycle of the roller hearth kiln.
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4-5
6-7
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9
10
11
12-13
14-15
16-17
18
19
Tem
per
atur
e °C
roller hearth kiln chamber kiln
I N T R O D U C T I O N
M A T E R I A L S
D E S I G N I N G
A P P L I C A T I O N
S O L U T I O N S
Heat treatment is an important processstep in research and industry. Heattreatment is also linked to energyconsumption. Energy is an essentialand valuable commodity and willalways continue to appreciate in value.For this reason, and also to support theneed for reducing energy consump-tion, furnace design and constructionhas undergone fundamental changesin recent years and these changes willcontinue. Success in achieving thesechanges has been mainly attributedto the use of structural ceramiccomponents and optimised ceramicmaterials which have replacedtraditional metal parts.
HALDENWANGER is the producer of high temperature, fine ceramics.
HALDENWANGER fine ceramics offer:Components with reduced wallthickness and therefore lower heatabsorptionComponents having higher thermalshock resistance allowing increased heating ratesLight, but mechanically strong and thermally stable kiln furniture,which is suitable for fast firingThin, self-supporting designs
HALDENWANGER
SIGNIFICANCE of ceramics for kiln construction and furniture
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I N T R O D U C T I O N
Intermittent Kiln
firing time/h
tunnel kiln
M A T E R I A L S
HALDENWANGER
SUMMARY of our ceramic materials
4
IMPERVIOUS MATERIALS
Alsint 99,7
Best, high temperature, ceramicmaterial for kiln construction with99,7% Al2O3 (the difference is mainlyMgO and SiO2).
Type C 799 according to DIN VDE 0335Refractoriness up to 1700 °CGood thermal shock resistance dueto high thermal conductivityHigh mechanical strengthHigh electrical resistivity
Recommended applications:
High working temperature, chemical attack, e.g. hydrogenand other reducing gasesClean kiln atmosphere Thin-walled designs having highthermal shock resistance
Pythagoras 1800 Z
Impervious, mullite high performancematerial
Refractoriness up to 1600 °CVery high thermal shock resistanceHigh mechanical strengthHigh electrical insulation even athigh temperaturesEvaporation extremely low, therefore no contamination of kiln atmosphere; no reactionwith heating elementMost suitable material for radiant heating tubesKiln tubes made ofPythagoras 1800 Z can be very thin-walled
Pythagoras
Most economical, mullite material forkiln components
Type 610 according to DIN VDE 0335Application temperatures up to1400 °CVery good chemical resistanceagainst gases free of fluorineFor kiln working under normalconditions Pythagoras has a goodthermal shock resistance and goodmechanical strength.Pythagoras is a very economicalmaterial being used as imperviousprotection sheaths and insulatorsfor temperature measurement.
Halsic-I
Silicon infiltrated reaction bondedsilicon carbide (SiSiC)
Reaction bonded SiC matrix, free ofpores, with residual metallic siliconHigh temperature ceramics forhighest mechanical loadsExtremely good oxidation resistanceLarge sized components possibleApplication temperatures up to1350 °CCorrosion resistant against strongacids and alkaline solutionsHigh thermal conductivity
Halsic-S
Pressureless sintered silicon carbide(SSiC)
Dense sintered SiC matrix with verylow percentage of closed poresHigh temperature ceramics forextreme mechanical loadsExtremely good oxidation resistanceApplication temperatures up to1600 °CCorrosion resistant against strongacids and alkaline solutions
POROUS MATERIALS
Alsint porous
High purity, porous 99,5% Al2O3
Better thermal shock resistancethan Alsint 99,7Refractoriness is similar toAlsint 99,7Similar chemical resistanceto Alsint 99,7Reducing gases, even pure hydrogen, do not attackAlsint porous.Alsint porous is mainly used for themanufacture of ignition dishes andcrucibles, but also for porous outerprotection tubes for thermocouples.Isostatic pressing is possible, sothat large tubes can also bemanufactured. Muffle tubes
SKA 100 NG
High purity, porous 99,5% Al2O3
Refractoriness up to 1700 °CHigh thermal shock resistanceGood chemical resistanceSKA 100 NG can be used inprotection furnaces with reducingor even hydrogen atmospheres.
SKA 100 NG as well as Alsint:
Does not react with the heatingelements, no contamination ofthe kiln atmosphere due toevaporation.Is most suitable for the porous,outer protection tube forthermocouples that mustwithstand very strong chemicalattacks.
M A T E R I A L S
HALDENWANGER 5
Sillimantin 60 NG
A specially developed material for usein kiln manufacture having an Al2O3
content between 73 – 75%.
Low porosityGood thermal shock resistanceNo reactions with the heating elementsWorking temperatures of up to1650 °CSpecial shapes possible forbridging long distancesbetween supportsExcellent chemical resistance.No contamination of the kilnatmosphere through evaporation.Suitable for kilns with a hightemperature gradientSillimantin 60 NG can be usedunder severe conditions as the outer protective tube intemperature monitoring devices.Rollers for roller kilns
Sillimantin 60
Most frequently used ceramic material in kiln designs
Type C530 according to DIN VDE 0335Application temperatures up to 1400 °CRefractoriness up to 1300 °C(subject to loading for rollerapplications)No reactions with heating elementsThis material can be formed usingmost moulding methods.Numerous special designs arepossible as well as a wide rangeof standard tubesThis material is used successfullyin laboratory and industrial kilns.
Sillimantin 65
A specially developed material for useas rollers having an Al2O3 contentbetween 78 – 80%
Refractoriness up to 1350 °C(subject to operational loading)Negligible reaction with glazesbecause of fine porosityRoller materials are detailedon page 14
Sillimantin KS
Most economical for support tubes
Refractoriness up to 1300 °CGood mechanical strengthLarge scale production with emphasis on the most commonlyused diameters permitting economical manufacture.A stock list of standard sizesis given on page 10.
SiC
Conventional, clay-bonded siliconcarbide
Excellent thermal conductivity allows the manufacture of thick-walled components having highmechanical strength.Furnace tubes with high thermalshock resistanceCan be used in oxidisingatmospheres up to 1400 °CHigh mechanical strength becauseof a large wall thicknessSighting tubes for opticaltemperature measurementOuter protection tubes fortemperature measurement up to 1200 °C in light and heavy metal smelts
Fused Silica
99,8% SiO2
Very low thermal expansionExcellent thermal shock resistanceCan be used continuously attemperatures up to 1000 °C
This material is used for:
Rollers in glass tempering furnacesCrucibles in high-frequency meltingRiser tubes for continuous castingCrucibles withstanding highthermal shock
Halsic-R
Recrystallised silicon carbide (RSiC)
Compact SiC matrix with open porosityClassic ceramic for hightemperature applicationsLarge sized components possibleReliable bonding of coatingsApplication temperatures: 1600 °C(oxidising) and approx. 2000 °C(under protective atmosphere)Resistant against strong acidsand alkaline solutions
Halsic-RX
Chemically doped recrystallisedsilicon carbide (RSiCdoped).
Compact SiC matrix with open porosityVery good oxidation resistanceMultiple increased life timecompared to Halsic-RIdeal material for porcelain fast firingLarge sized components possibleReliable bonding of coatingsApplication temperatures up to1650 °C (oxidising)
Insulation compounds are used forembedding or fixing electric heatingelements on ceramic parts. Anexception is the compound SKA 90(see right column).
Insulation compounds are used forfilling gaps and cracks as well as forkiln repair. Firing supports can also bemanufactured from these compounds.The compounds are prepared byadding water to the powder and set by heating. Final strength is achievedby heating to the required temperatureindicated in the table on page 7.
Shrinkage is minimal using thisprocess. HALDENWANGER insulationcompounds are free from electrolytesto ensure good electrical insulationeven at extremely high temperatures.
Preparation instructions anduse of insulation compounds
The powder is mixed thoroughly withwater which is free from electrolytes.For good processability the pasteshould not stick to the back of one’shand. After embedding, the insulationmaterial should be left for about 24 hours to dry at approx. 50 °C. Thematerial can then be shaped, filed or drilled.
Final strength of the insulation materialis achieved by heating it to the requiredtemperature. It is recommended tosurround the kiln tube with a layer ofinsulation during this heat treatment.
Heating for the first time should bedone with care. Initial blackening of the compounds 1000 and 1000 Fduring heating is due to carbonisationof the organic binder and will disappearafter soaking temperature is reached.
If too much powder is mixed, the remainder can be dried and usedagain. Contamination may, however,render the insulation compounds unusable.
Information about kiln design
The electric heating coils must beevenly spaced and checked by meansof a gauge prior to embedding.
For kilns heated with nickel-chrome elements, i.e. for temperaturesexceeding 1000 °C, grid voltage is notrecommended.
The heating coils will last longer if the voltage is 110 V or less. If possible,the insulation compound should be prepared using water free ofelectrolytes.
Because of its ion content, normal tapwater reduces the electrical resistivityof the insulation substances. Thisshould be taken into consideration iffurnaces for high temperatures areinvolved.
If the powders are mixed frequently,water totally free of electrolytes mustbe used.
Insulation Compound 150
Our compound 150 is used forembedding heating wires havingdiameters of approximately 1 – 3 mm.
Due to its composition the compoundcan be used up to a temperature of approx. 1350 °C. The settingtemperature is 1000 °C. Please refer to “Insulation Compounds” for morepreparation details.
Insulation Compounds 60 – 1000 F
For fixing heating wires having adiameter of 1 mm or more, werecommend the use of compound 60at temperatures not exceeding 1350 °Cand compound 1000 for temperaturesup to 1800 °C. Heating wires with adiameter of less than 1 mm should beembedded with compound 250 attemperatures up to 1350 °C and withcompound 1000 F for temperatures up to 1800 °C.
Insulation Compound SKA 90
This substance was tailored to withstand slag attack. It is used for crucible linings in which precious metals are melted. Without such liningscontamination of molten metals mayoccur. Besides excellent corrosion resistance this compound also has an extremely good thermal shock resistance.
HALDENWANGER
INSULATION COMPOUNDS
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M A T E R I A L S
1
2
M A T E R I A L S
HALDENWANGER 7
Isolationsmix no.
60coarse
grain structure
150medium
grain structure
250fine
grain structure
1000coarse
grain structure
1000 Ffine
grain structure
SKA 90
Refractoriness
SK 38 = 1825 °C
SK 38 = 1825 °C
SK 38 = 1825 °C
SK 42 = 2000 °C
SK 42 = 2000 °C
SK 38 = 1825 °C
Settingtemperature
1000 °C
1000 °C
1000 °C
1300 °C
1300 °C
Guide analysis
Al2O3 90,50 %SiO2 9,00 %
Al2O3 90,50 %SiO2 9,00 %
Al2O3 90,50 %SiO2 9,00 %
Al2O3 99,70 %SiO2 0,01 %
Al2O3 99,70 %SiO2 0,01 %
Al2O3 95,00 %SiO2 4,75 %
Grain size distr.
µm %
> 355 4,80> 200 78,60> 100 92,70> 90 94,10< 90 5,90
> 355 7,30> 200 11,80> 100 49,40> 90 63,50< 90 36,50
> 355 6,50> 200 10,00> 100 15,00> 90 23,20< 90 76,80
> 355 37,50> 200 71,00> 100 87,60> 90 92,70< 90 7,30
> 355 0,25> 200 2,25> 100 36,55> 90 54,15< 90 45,85
> 355 40,10> 200 81,20> 100 93,40> 90 94,50< 90 5,50
Max. temperature
1350 °C
1350 °C
1350 °C
1800 °C
1800 °C
1750 °C
Seeger cone small
at 150 °C/h
heatingrate
Available Insulation Compounds
M A T E R I A L S
WH Refractory Cement 1500
Directions for useWH refractory cement is an inorganicadhesive which is resistant totemperatures of more than 1500 °C.The surfaces to be joined togethermust be carefully cleaned of dirt, grease and oil. Remove all traces of thechemicals used for cleaning (petrol,acetone, soap powder) before applyingthe WH refractory cement. The facesmust be completely dry.Depending on the consistency re-quired, the cement should be mixedhomogeneously using 2 – 4 parts powder to one part liquid.
Apply a layer on each of the surfaces to be stuck together. The cement setsby chemical reaction and should be used within approx. 1 hour. Goodmechanical strength of the refractorycement is obtained after about 24 to36 hours at room temperature. Dryingat higher temperatures will acceleratethe hardening process and improve the mechanical strength.The mechanical strength of the WHrefractory cement as a function ofdrying temperature was verified intests. Square-sectioned rods of Sillimantin60 were cemented together at definedfaces and heated to a temperature of approx. 1500 °C. The cementedareas of the two pieces were thenstressed at room temperature until fracture occurred. The relationbetween mechanical strength and firing temperature proved to be linear.
WH Refractory Cement 1800
This cement is mainly used for joiningpieces operating at high temperaturesof at least 1700 °C.It is supplied as a single-componentsystem ready to use and after dryingfor approx. 24 hours at 100 °C thecement has a certain strength. Thestrength is reduced as the temperatureincreases up to approx. 800 °C. Above 800 °C the strength increasescontinuously and reaches its highestvalue at 1800 °C.Refractory cement 1800 should bekept closed at all times. A thin film ofhardened cement may have to beremoved before use.
WH Refractory Cement 1300/1800
This cement is also supplied ready foruse. It can be applied in the same fieldsas refractory cement 1800. However,its strength increases continuouslywith rising temperature. There is no reduction in strength up to 800 °C asdescribed for refractory cement 1800.It must be pointed out that this cementis hygroscopic. Furthermore, it canhave a corrosive effect on metals.Therefore, it is not suitable forembedding metal parts or heatingelements.
WH Refractory Cement 98
This cement is supplied as a single-component system. It must beprepared to a pulpy consistency by adding water and is then ready for application. The cement should be used within approx. 1 hour beforesetting starts. Compared to refractorycement 1500, this cement has the advantage of being suitable fortemperatures up to 1700 °C. Shrinkageduring firing is very low (approx. 2%).
Under certain conditions refractorycement 98 can be used as an electricalinsulator.
WH refractory compound WH 98.
HALDENWANGER
REFRACTORY CEMENTS
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Important:Cements are not insulatingcompoundsCements are not suitable for fixing any kind of heating wireCements are not to be used in furnace construction.
M A T E R I A L S
HALDENWANGER
Physical
PROPERTIES
9
Unit
Alsi
nt 9
9,7
Pyth
agor
as 1
800
Z
Pyth
agor
as
Hals
ic-I
Hals
ic-S
Alsi
nt p
orou
s
Silli
man
tin 6
0 NG
Silli
man
tin 6
0
Silli
man
tin 6
5
Silli
man
tin K
S
SiC
(cla
y bo
nded
) 1)
Quar
zgut
Hals
ic-R
Hals
ic-R
X
Impervious Materials Porous Materials
Al2O3 content
Alkali content
SiC content
Si content (free)
Type acc. to DIN VDE 0335
Water absorption
Leakage rate at 20 °C
Density
Flexural strength 20 °C (3-point)
Flexural strength 1300 °C (3-point)
Young’s modulus
Hardness (Mohs scale)
Thermal expansion 20 - 700 °C
Thermal expansion 20 - 1000 °C
Thermal conductivity 20 - 100 °C
Max. working temperature 4)
Permissible continuous temperature for protection sheaths acc. to DIN 43724Permissible continuous temperature for insulating rodssheaths acc. to DIN 43724
Dielectric strength acc. to IEC 672-2
Volume resistivity at D.C. 20°C
Thermal shock resistance
Pore size (average)
Specific heat capacity 20 - 100 °C
%
%
%
%
–
%
hPa · dm3 · s-1
g · cm-3
MPa
MPa
GPa
–
10-6 · K-1
10-6 · K-1
W · m-1
· K-1
°C
°C
°C
kV · mm-1
Ω · cm
–
µm
J kg-1
· K-1
99,7
–
–
–
799
≤ 0,2
10-10
3,75-3,94
300
–
300-380
9
7,8
8,6
25
1700
1600
1800
26
1014
good
–
900
76
0,5
–
–
–
≤ 0,2
–
3,0
150
–
150
8
5,6
6,0
6
1600
–
–
26
1013
good
–
900
60
3,0
–
–
610
≤ 0,2
10-10
2,6
120
–
100
8
5,4
6,0
2
1400
1500
1500
26
1013
good
–
900
–
–
88-92
8-12
–
≤ 0,1
–
3,1
240-280 2)
250-300
370
–
3,7
4,3
100
1350 5)
–
–
–
–
very good
–
900
–
–
≥ 99
≤ 0,1
–
≤ 0,1
–
3,1
350-400 2)
370-420 2)
420
–
4,5
5,0
124
1600 5)
–
–
–
–
verygood
–
1000
99,5
–
–
–
–
2-7
–
< 3,6
70-110 2)
–
–
–
7,8
8,6
–
1700
–
–
–
–
good
1-3
–
72-74
≤ 1
–
–
–
6
–
2,65
60
–
85
–
5,2
5,7
–
1650
–
–
–
–
good
8,5
900
72-74
≤ 1
–
–
530
9
–
2,35
45
–
60
–
5,3
5,7
1,4
1350
1600
–
–
–
very good
2
800
78-80
≤ 1
–
–
–
11
–
2,45
55
–
75
–
5,3
6,3
1,4
1400
–
–
–
–
very good
1,5
900
70
≤ 1
–
–
–
9
–
2,35
45
–
60
–
5,3
5,7
1,4
1350
–
–
–
–
very good
2
–
–
–
70-90
–
–
8-13
–
2,2-2,5
30
–
–
–
5
5
–
1300
–
–
–
–
very good
3
–
–
–
–
–
4-6
–
1,92-2,00
30-40
45-60 3)
30-40
–
–
0,5-0,9
–
1000
–
–
–
–
very good
≤ 0,2
–
–
–
> 99
≤ 0,1
–
5
–
2,7
80-100 2)
90-110
280
–
3,9
4,5
35
1600 5)
2000 6)
–
–
–
–
very good
24
–
–
–
> 99
≤ 0,1
–
5
–
2,7
80-100 2)
90-110
280
–
3,9
4,5
35
1650 5)
2000 6)
–
–
–
–
very good
24
–
The physical properties stated above result from test pieces. These values can only be used as a reference to other forms and dimensions depending on manufacturing process, geometry, surface finish and machining. In practice, e.g. Alsint 99,7 components have a flexural strength of between 160 and 340 MPa. 1) properties for general information only due to different qualities,2) 4-point bending strength, 3) at 700°C, 4) depending on load, 5) in oxidising atmosphere, 6) in inert atmosphere.
D E S I G N I N G
HALDENWANGER10
Po
rous
Mat
eria
ls
Alsint 99,7
Type C799 (DIN VDE 0335)Al2O3 content 99,7%
Pythagoras
Type C610 (DIN VDE 0335)Al2O3 content approx. 60%
Alkali content 3%
Pythagoras 1800 Z
Al2O3 content approx. 76%
Alkali content 0,33%
CERAMIC TUBESSelection of our production programme
0,8 x 0,31,3 x 0,71,6 x 1,01,8 x 1,22,0 x 1,02,7 x 1,73,0 x 2,04,0 x 2,05,0 x 3,06,0 x 4,08,0 x 5,09,0 x 6,09,6 x 6,4
10,0 x 6,012,0 x 8,012,7 x 8,914,0 x 10,015,0 x 10,017,0 x 12,017,5 x 11,120,0 x 15,024,0 x 18,0
26 x 2028 x 2230 x 2335 x 2738 x 3042 x 3446 x 3850 x 4055 x 4560 x 5065 x 5670 x 6072 x 6275 x 6580 x 7085 x 7590 x 8095 x 85
100 x 85105 x 90110 x 95115 x 100
120 x 100120 x 105130 x 110140 x 120140 x 125150 x 130155 x 135160 x 140170 x 150175 x 155180 x 160185 x 165190 x 170200 x 175220 x 200240 x 220260 x 240270 x 250300 x 280320 x 300420 x 380450 x 430
Outer x inner Ø mm
0,8 x 0,31,3 x 0,71,6 x 1,01,8 x 1,22,0 x 1,02,7 x 1,73,0 x 2,04,0 x 2,05,0 x 3,06,0 x 4,08,0 x 5,09,0 x 6,09,6 x 6,4
10,0 x 6,012,0 x 8,012,7 x 8,914,0 x 10,015,0 x 10,015,0 x 11,017,0 x 12,017,0 x 13,017,5 x 11,1
20 x 1522 x 1724 x 1824 x 1926 x 1826 x 2028 x 2230 x 2331 x 2535 x 2738 x 3040 x 3245 x 3848 x 4050 x 4052 x 4255 x 4658 x 5060 x 5065 x 5570 x 6075 x 65
80 x 7085 x 7590 x 7590 x 8095 x 85
100 x 85105 x 90110 x 95115 x 100120 x 100125 x 105130 x 110140 x 120140 x 125150 x 130160 x 140170 x 150180 x 160190 x 170200 x 180240 x 220300 x 280
Outer x inner Ø mm
48 x 4053 x 4360 x 5263 x 5370 x 6073 x 6375 x 6580 x 7082 x 7285 x 7486 x 7687 x 7788 x 7893 x 8395 x 85
100 x 90105 x 90115 x 105120 x 110
Outer x inner Ø mm
Sillimantin 60 NG
medium fine structureAl2O3 content
approx. 73–75%
20 x 1522 x 1724 x 1926 x 1828 x 2230 x 2335 x 2740 x 3250 x 4060 x 5070 x 6080 x 7090 x 75
100 x 85110 x 95120 x 100130 x 110140 x 120160 x 140200 x 175250 x 230330 x 310
20 x 1522 x 1724 x 1926 x 1828 x 2230 x 2335 x 2740 x 3250 x 4060 x 5070 x 6080 x 7090 x 75
100 x 85110 x 95120 x 100130 x 110140 x 120160 x 140200 x 175250 x 230330 x 310
15 x 720 x 1220 x 1525 x 1525 x 1830 x 2035 x 2540 x 3045 x 3550 x 4055 x 4560 x 48
26 x 1828 x 2230 x 2335 x 2640 x 3250 x 4055 x 4560 x 4965 x 5470 x 5875 x 6280 x 6685 x 7190 x 7495 x 79
100 x 84105 x 89110 x 94115 x 99120 x 104125 x 109130 x 114
17 x 1220 x 1522 x 1724 x 1926 x 1826 x 2028 x 2230 x 2331 x 2533 x 2835 x 2740 x 3245 x 3550 x 4055 x 4560 x 5065 x 5570 x 6075 x 6580 x 7085 x 7590 x 75
20253035404550556065707580859095100
We can grindintermediate sizes asper your requirement.
Outer x inner Ø mm
Sillimantin 60
Type 530 (DIN VDE 0335)medium fine structure
Al2O3 content approx. 73–75%
Outer x inner Ø mm
Sillimantin KS
medium fine structureAl2O3 content approx. 70%
Outer x inner Ø mm
SKA 100 NG
medium fine structureAl2O3 content approx. 99,5%
Outer x inner Ø mm
Siliciumcarbid
fine and coarse structureSiC content
70%
Outer x inner Ø mm
Quarzgut
especially for flatglass tempering
Ø mm
max. length on inquiry, max. diameter on inquiry
Imp
ervi
ous
Mat
eria
ls
fa
l
fa
l
D E S I G N I N G
HALDENWANGER 11
TOLERANCESaccording to DIN 40680
Accuracy
DIN VDE 0335, Type
Manufacturing method:
Cast
Turned
Non metered pressed
Metered semi wet pressed
Metered dry pressed
Machined in the green state
Extruded:Ø 30 mm and above
Extruded:up to Ø 30 mm
± 0,15± 0,20± 0,25± 0,30± 0,35± 0,40± 0,45± 0,50± 0,55± 0,60± 0,65± 0,70± 0,80± 0,90± 1,00± 1,20± 1,40± 1,60± 1,80± 2,00± 2,20± 2,50± 2,80± 3,00± 3,40± 3,80± 4,20± 4,60± 5,00± 5,50± 6,10± 6,80± 7,60± 8,30± 9,00± 9,50± 10,00± 0,01 · d
± 0,4± 0,6± 0,7± 0,8± 1,0± 1,2± 1,2± 1,5± 1,5± 2,0± 2,0± 2,0± 2,5± 2,5± 2,5± 3,0± 3,5± 4,0± 4,5± 5,0± 5,5± 6,0± 6,5± 7,0± 7,5± 8,0± 9,0± 10,0± 11,0± 12,0± 13,0± 14,0± 15,0± 16,0± 17,5± 19,0± 20,0± 0,02 · d
468
101316202530354045505560708090
100110125140155170185200250300350400450500600700800900
1000
above above above above above above above above above above above above above above above above above above above above above above above above above above
30405060708090
100110125140155170185200250300350400450500600700800900
1000
medium530/610 799
0,150,200,250,300,350,400,450,500,550,650,700,800,850,901,001,251,501,752,002,252,503,003,504,004,505,000,5% · I
1,71,81,92,02,12,12,22,32,42,52,62,72,93,03,13,53,94,34,75,15,56,37,17,98,79,51,5
We request your inquiry for closer tolerances.
Manufacturing method
Cast, turned, extruded for parts Ø 30 mm and above
Extruded for parts up to Ø 30 mm, non metered pressed, metered semi wet pressed metered dry pressed, machined in the green state
Degree of accuracycoarse medium
Deflection of a cylindrical body
applicationcustomary
applicationcustomary
coarse
• ••
The values determined for the degree of accuracy "coarse" do not apply forfirst manufacture. Special agreements apply here.• Customary manufacturing method
above above above above above above above above above above above above above above above above above above above above above above above above above above above above above above above above above above above above above
up to4 up to6 up to8 up to
10 up to13 up to16 up to20 up to25 up to30 up to35 up to40 up to45 up to50 up to55 up to60 up to70 up to80 up to90 up to
100 up to110 up to125 up to140 up to155 up to170 up to185 up to200 up to250 up to300 up to350 up to400 up to450 up to500 up to600 up to700 up to800 up to900 up to
1000
up to30 up to40 up to50 up to60 up to70 up to80 up to90 up to
100 up to110 up to125 up to140 up to155 up to170 up to185 up to200 up to250 up to300 up to350 up to400 up to450 up to500 up to600 up to700 up to800 up to900 up to
1000
mediumPermissible
deviation in mm
coarsePermissible
deviation in mm
mediumPermissible
deviation in mm
Degree ofaccuracy
Degree ofaccuracyNominal dimensional
range for length
coarsePermissible
deviation in mm
530/610 799
•
•
••
•
•• •
+ 0,8% · I
Deflection of a noncylindrical body
Nominal dimensionalrange for diameter
or length in mm
Diameter tolerances – deflectional tolerances without grinding to DIN 40680, issue 1983
A P P L I C A T I O N
HALDENWANGER
EXAMPLES OF APPLICATIONfor ceramic materials
12
A P P L I C A T I O N
HALDENWANGER 13
Roller hearth kilns for fast firing of walland floor tiles have been used fornearly 25 years. In this type of kiln theproducts to be fired are transportedthrough the kiln by means of rotatingceramic rollers. Since the beginningHALDENWANGER has supplied thevarious manufacturers and users ofkilns with oxide and non-oxide ceramicrollers. In the past, the diameter ofrollers was up to 55 mm with a lengthof approx. 2000 mm. Because ofincreased capacity demands, the walland floor tile industry asked for moreefficient kilns. That is the reason whykilns became wider and therefore therollers became longer. Today there areroller diameters of 30, 33.7, 40, 42, 45and 50 mm for maximum roller lengthof approx. 3700 mm. This correspondsto a useable kiln width of approx.2500 mm.
Roller tolerances have also becomemuch tighter. Today, diameter tole-rances of +/- 0,2 to +/- 0,3 mm are typical and roller bending is as small as 1,0 to 1,5 mm which corresponds to a TIR of 2-3 mm. Additionally, theoverall length taper specification of no more than 1mm is today a standardrequirement.
Production capacity allows us to pro-duce nearly all standard dimensions.The rollers must have good refractoryproperties to guarantee a perfectoperation for a given temperature andload. Furthermore, there is the need to
HALDENWANGER
CERAMIC ROLLERS
14
A P P L I C A T I O N
Worldwide, HALDENWANGER isthe only manufacturer of rollers forkilns and furnaces able to supplythe complete programme of rollermaterials. With our know-how ofproducing different mullite and SiC-based materials we offer custom-made solutions.
change rollers during kiln operation. Insuch cases, the high thermal gradientswhich rollers have to withstand meansthat a material must be selected havingsufficient thermal shock resistance.
Oxide ceramic rollers, these are ourmaterials Sillimantin 60, Sillimantin 65,Sillimantin 60 NG, are used in rollerhearth kilns for firing wall and floortiles. Non-oxide ceramic rollers,these are our materials Halsic-R(RSiC) and Halsic-I (SiSiC), areused in roller hearth kilns for firing sanitary ware andporcelain. These materialsare used because of thebetter creep resistancecompared to the oxideceramic rollers.
Before installing the rollers in the kiln they must be completely dry. This is very important if the rollers arechanged during operation. Drying isusually done by storing the rollers on or above the furnaces (utilisation of waste heat).
Heat losses in the kiln arise from theopen ends of the roller. By usingceramic fibre plugs the rollers aresealed at both ends. The plugs usuallyhave a maximum length of 100 mm to 200 mm.
The oxide ceramic rollers mustcontinue to rotate whilst they areheated up or cooled down. This is veryimportant, for example, if a roller hearthkiln is to be shut down for maintenanceor technical reasons.
Stationary oxide ceramic rollers, even for a short time, results in rollerbending. The drive to the rollers shouldnever be switched off even at kilntemperatures of 500 °C to 600 °C, asfrequently occurs. Stationary rollerssubjected to the above-mentionedtemperature will be damaged! When
the kiln is re-started, considerablebreakage is to be expected. The rollersmust also be kept rotating even overshort breakdown periods.
HALDENWANGER ceramic rollers areused for the firing of:
wall and floor tiles up to 1300 °C
tableware porcelain up to 1420 °C
sanitary porcelain up to 1300 °C
ferrites up to 1300 °C on supporting setters
heat treatments of metals up to 1200 °C.
Ceramic Supporting Rollers forGlass Tempering Furnaces
In glass tempering furnaces the glass is transported on rollers through thefurnace. Product is run directly on therollers, i.e. without supports.
The tempering time can be regulatedvia the rotational speed of the rollers
as well as by applying different heatingsystems.
All large sized glass plates are subjectto this secondary thermal treatmentbecause of new regulations. (singlepane safety glass)
The aim of this process is to cause pre-stressing the glass through heat,so that there are no sharp splinters ifthe glass breaks. Like safety glass, the pane must break into many harmlessparticles.
Because of the sensitivity of the glasssurface, the ceramic rollers used mustbe very smooth and free of the smallestundulation. The bending and theconcentricity are very importantfactors, too.
Furthermore, the ceramic materialmust have good thermal shockresistance properties in order towithstand changes of temperatureoccurring in the process.
The material used for these rollers isour Fused Silica. In use today are solidas well as hollow fused silica rollerswhich can be supplied with mountedmetal end caps.
HALDENWANGER 15
A P P L I C A T I O N
A P P L I C A T I O N
HALDENWANGER
EXAMPLES OF APPLICATIONSfor ceramic components
16
By means of selected examples youwill recognize how we are handling and solving problems. It is shown, how we co-operate with our customers to achieve optimal results. The follow-ing pages explain the practical applic-ations of our ceramics in furnace construction.
Annealing Boxes + Melting Crucibles
Annealing boxes and melting cruciblesmade from ceramic material arerequired in almost every industrialsector. The type of HALDENWANGERmaterial used depends on the chemicalor thermal stress the material has to withstand. The various sizes andgeometries are determined by ourcustomers. We are able to providehelpful advice influencing productquality and costs through our widerange of design possibilities. Suchwork requires a joint effort in selectingthe materials and determining theproduct geometry.
Fused Silica
Working temperatures are possible up to 1000 °C. The low linear thermalexpansion and therefore good thermalshock resistance permits short heat-up times.
Alsint Porous
Alsint porous is the right material fortemperatures exceeding 1300 °C, evenin a reducing atmosphere. The maincharacteristic of this material is itschemical resistance. Heat-up ratesmust be adapted to this material. It isalso possible to influence the requiredthermal shock resistance by geometryand wall thickness.
Support Tubes
Support tubes are required for theconstruction of furnaces with exposedheating coils. Our material SillimantinKS has proved itself over the years andis used by many renowned companiesbuilding kilns. All commonly used sizesof support tubes can be deliveredex stock. Special dimensions of Sillimantin 60 are manufactured (seetable on page 10).If the usual material, Sillimantin KS,does not meet the requirements of your special application, there are thefollowing additional possibilities:
Alsint 99,7 with its higher supporting capacity, greater supporting distance (without bending), gastightness and chemical inertness.
Pythagoras as an imperviousmaterial has a better refractorinessthan Sillimantin KS.
Sillimantin 60 NG combines thegood refractory properties of Alsint with good resistance to thermal shock.
Firing Supports
In the ceramic and electrical industryfiring supports or kiln furniture arerequired for kiln car structures.Normally in the ceramic industry tube sections, for example of the size 55 x 45 x 200 up to 300 mm, areused in order to keep the firing settersat the right distance. In the productionof ferrites rectangular solid shapes ofdifferent sizes are used for the samepurpose. These supports also carry the setter plates with the ferrites onthem. The high mechanical strength of ceramics enables you to use small firing supports. The result is animprovement of the relation betweenkiln furniture and products to be fired.
Kiln Furniture Structures
Please refer to our leaflets “Halsic-R/Halsic-RX, Halsic-I/Halsic-S” for ouradditional manufacturing programme.
HALDENWANGER 17
A P P L I C A T I O N
A P P L I C A T I O N
8r 2r
4656
46 56
100110
80 90
WS: 6.5
95105
95 105
WS: 6.8
160170
43 53WS: 5.5
155170
65 81
WS: 9.5
135150
185
200
WS: 10.0
10r 5r
7483
63 74
101122
84 103
WS: 11.0
180195
89 105
WS: 8.5
175195
127
145
20r 10r
164
86 102
175
180
265280
130
145
WS: 9.5
95105
5412
0
75
50
118133
82 97
17r9r
5967
140160
110
1358778
145170
115
140
WS: 13.8
227255
177
200
5r
HALDENWANGER
SIZESof muffles, open both ends
18
Dimensions stated here for a wide range of muffles are for Sillimantin 60 only. For Sillimantin 60 NG muffles, please use a correction factor of –5%.
The objective of this brochure is todemonstrate how we are helpingour customers to solve problemsencountered in kiln design. However,HALDENWANGER’s capabilities donot stop here. Numerous design pro-grammes involving technical ceramicsvery often mean ‘difficult problems’for the manufacturers and in suchcircumstances HALDENWANGER isthe company to provide the solutions.
Technical ceramics have been used for many years in various productionprocesses. Many new fields are beingadded to the already existing broadrange of applications ranging from space exploration and mechanical engineering to chemistry and most sophisticated electronics.
Additional application areas forHALDENWANGER technical ceramics are:
Mechanical applications, from shafts to cylinder liners
Refractory applications, from saggers to heat-exchangers
Chemical applications, from evaporating dishes to combustion boats
Electronic and high current appli-cations, from insulation bushes tocomponents for electron tubes
Whatever the requirement, we believeHALDENWANGER is your competentpartner right at the planning stage.
When you are next confronted with an engineering challenge for which the solution could be ceramics thenremember, HALDENWANGER is the specialist.
HALDENWANGER
TECHNICAL CERAMICS
19
S O L U T I O N S
Alsint 99,7 insulating ring (Ø 320 mm, 4 mm wallthickness) for the satellite “COS-B”
Special parts designed for customer applications