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Products Manufactured from Flexible Graphite Foil
Expanded Graphite
SIGRAFLEX®
Broad Base. Best Solutions.
S I G R A F L E X ®
S I G R A F L E X ®
SGL Group – The Carbon CompanyOne of the word�s leading manufacturers of carbon-based products Page 4
Sealing Products Made fromExpanded Natural Graphite Page 5
Production and CharacteristicProperties Page 6
Product Designations Page 7
Product Overview Page 8
Mechanical and PhysicalProperties of
� SIGRAFLEX Foils Page 9
� SIGRAFLEX Sheets, Unreinforced Page 11
� SIGRAFLEX Sheets, Reinforced Page 14
Approvals and Certificates Page 17
Chemical Resistance of SIGRAFLEX Page 18
Market Approach and Customer Service Page 20
Our Expertise is Your Advantage Page 21
Processing of
� SIGRAFLEX Foils Page 22
� SIGRAFLEX Sheets Page 23
Advice on Application for Stuffing Box Packings Page 24
Advice on Application for Gaskets Page 25
High-Quality SIGRAFLEX Gasket Systemsand Fields of Application Page 26
Recommended SIGRAFLEX Products forVarious Applications Page 27
Commonly UsedConversion Factors Page 28
Definitions of Gasket Factors Page 31
Contents
3
S G L G r o u p – T h e C a r b o n C o m p a n y
4
SGL Group – The CarbonCompany – is one of theworld's leading manu-facturers of carbon-based products. Ourcomprehensive portfolioranges from carbon and graphite products to carbon fibers andcomposites.
Due to their unique properties,carbon and graphite areindispensable materials for manyindustries, such as the steel,aluminum, semiconductor,energy, automotive, aerospace,sporting goods, chemical andenvironmental protectionindustries.
We constantly aim to improveour products and services to meet our customers’ specificrequirements. Our company-wide SGL Excellence Initiativeand Six Sigma, which we apply as core methods, are state-of-the-art tools for bringingcontinuous improvement to allareas, including our processes,engineering know-how, productdevelopment and innovation, as well as the expertise of ourworkforce. We keep in closecontact with our customers,suppliers and logistic partners to help achieve this.
Many decades of experience in handling carbon materials of all kinds and also intensivedevelopment work haveenabled us to optimize ourmanufacturing processes at ourglobal production sites inEurope, North America andAsia.
E x p a n d e d G r a p h i t e
5
SIGRAFLEX®
Sealing Products for aClean Environment
Our Business Line ExpandedGraphite manufactures flexiblegraphite foils and graphitesealing sheets from expandedgraphite. They are marketedunder the SIGRAFLEX®
trademark to the automotiveand industrial sealing industryworldwide. SIGRAFLEX isavailable in all majorindustrialized countries. All standard SIGRAFLEX prod -ucts are available from stock.
We carry out constant productmonitoring using non-destructivemethods during manufacturingoperations and also conductrandom checks involving speci -fied analytical processes.Needless to say that our qualitymanagement system is certifiedunder the relevant standards.
Thanks to their high quality, our products can be used even in the most demandingapplications. By offeringproducts of guaranteed quality,we can enter into long-termcooperation agreements in a spirit of mutual trust.
Our technical and marketingstaff maintain close contactswith the company’s customers,such as plant constructors and operators of complexplants in the chemical andpetrochemi cal industries,power stations and foundries.Besides choosing the rightproducts for particularapplications, they are alsoavailable to carry out the design calculations for seals.
SEALING PRODUCTS MADE FROM EXPANDED NATURAL GRAPHITE
SIGRAFLEX® sealing sheets and gaskets
Sabic Polyolefine GmbH productionplant at the Gelsenkirchen site
S I G R A F L E X ®
6
PRODUCTION ANDCHARACTERISTICPROPERTIES
The raw material used in theproduction of SIGRAFLEX isnatural graphite flake with well-ordered crystalline struc -tures. We select the highest-quality raw materials from the various grades availablearound the world. Graphiteintercalation compounds areproduced from the naturalgraphite flakes. The thermaldecomposition (expansion) of these compounds leads to the formation of loose “worms“ of pure graphite, which arecompressed into foils withoutbinder or filler. The resultingalignment of the graphiteparticles and their planarstructures produces a highdegree of directional depen -dence (anisotropy) in theproperties. The high purity ofSIGRAFLEX derives from theraw materials used, as well as from the quality of themechanical, chemical andthermal purification processes.
Graphite sheets are manu fac -tured in various forms, namelyunreinforced, impregnated orreinforced. A distinction ismade between sheets rein -forced with perforated sheetsteel and those using smoothstainless steel foil reinforcement.The special impregnation ofour sheets ensures scratchresistance, antistick behavior,greater strength and lower gas permeability.
Characteristic Properties
� Low permeability to gases and liquids
� Flexibility, soft texture
� Resistance to most media
� Absence of health hazard;asbestos-free
� Environmental compatibility
� Suitability for use attemperatures ranging from -250°C up to approx. 3000°C depending oninstallation and serviceconditions:– in an inert atmosphere
up to approx. 800°C (limits imposed by metalreinforcement to beobserved)
– for applications in air at more than approx.400°C, users shouldrequest our advice
� Absence of binders meansno ageing or embrittlement
� Long-term stability ofcompressibility andrecovery over a widetemperature range
� No cold or warm flow up to maximum permissiblegasket pressure
� High residual stress
� Properties highlyanisotropic, particularly inrespect of electrical andthermal conductivity
� Resistance to radiation
� Very good resistance tothermal shock
� Ease of cutting or punching
250 µm
250 µm
Natural graphite flake
Expanded graphite “worm“
Flexible graphite foil
S I G R A F L E X ®
7
PRODUCTDESIGNATIONS
Type
Thicknessin hundredths of a mm
Bulk densityof graphite in tenths ofg/cm3
Ash content
Reinforcements(in V types only)
Upgrading
Typical product designation
S I G RA F L E X V 200 10 C 2 I
F FoilL SheetV Reinforced sheet
Z <_ 0.15 %E <_ 1.00 % C <_ 2.00 %D <_ 4.00 %APX <_ 2.00 % advanced
antioxidation technology
1 0.2 mm perforated steel sheet,DIN material no.1.0330
2 0.1 mm perforated stainlesssteel sheet, ASTM material no. 316 (L)
3 0.05 mm stainless steel foil, ASTM material no. 316 (L), unbonded
4 0.05 mm stainless steel foil,ASTM material no. 316 (L), bondedFor other reinforced materials, users should request our advice
E Sheet type EMAILI ImpregnationS Self-adhesive finishX Corrosion inhibitorI-P TA Luft (German Clean
Air Act) grades
S I G R A F L E X ®
8
Product Overview Table 1
Product Type Thickness Width Length Graphite[mm] [m] [m] bulk density
[g/cm3]
Rolls*)
F.....C 0.35 to 1.0 0.5/1.0 50/100 0.7 to 1.3 F.....D 0.35 to 1.0 0.5/1.0 50/100 0.7 to 1.3F.....E 0.35 to 1.0 0.5/1.0 50/100 0.7 to 1.3
SIGRAFLEX F.....APX 0.1 to 1.0 0.5/1.0 50/100 0.7 to 1.3FOIL F.....Z 0.1 to 1.0 0.5/1.0 50/100 0.7 to 1.3
F.....ZX 0.5 0.5 50 0.7F.....CS/ZS 0.5/1.0 0.5 25/50 1.0
Sheet L.....Z 1.0/1.5/2.0 1.0 1.0 1.0
SIGRAFLEX L.....C 1.0/1.5/2.0 1.0 1.0 1.0 BASIS
Homogeneous, free of adhesives and binders
Impregnated sheetL.....CI impregnated 1.0/1.5/2.0 1.0 1.0 1.0
SIGRAFLEXSTANDARD
Homogeneous, free of adhesives and binders
Reinforced sheets
SIGRAFLEX V.....C4 0.5 to 3.0 1.0 1.0 1.0 ECONOMY
Stainless steel foil reinforcement, 316 (L), 0.05 mm, bonded
SIGRAFLEX V.....C2I impregnated 1.5/2.0/3.0 1.0/1.5 1.0/1.5 1.0UNIVERSAL
Perforated stainless steel sheet reinforcement, 316 (L), 0.1 mm, unbonded
SIGRAFLEX V.....Z3I impregnated 1.0 to 4.0 1.0/1.5 1.0/1.5 1.1HOCHDRUCK
Multiple stainless steel foil reinforcement, 316 (L), 0.05 mm, unbonded
SIGRAFLEX V.....Z3E 2.0/3.0 1.0 1.0 1.1EMAIL
Two stainless steel foil reinforcements, 316 (L), 0.05 mm, unbonded
SIGRAFLEX V.....C2I-P impregnated 1.6/2.0/3.0 1.0/1.5 1.0/1.5 1.0UNIVERSALPRO Perforated stainless steel sheet reinforcement, 316 (L), 0.1 mm, unbonded
SIGRAFLEX V16010C3I 1.6 Gaskets with inner eyelet 1.1SELECT
Two stainless steel foil reinforcements, 316 (L), 0.05 mm, unbonded
SIGRAFLEX V.....Z3I-P impregnated 1.5 to 4.0 1.0/1.5 1.0/1.5 1.1HOCHDRUCKPRO Multiple stainless steel foil reinforcement, 316 (L), 0.05 mm, unbonded
SIGRAFLEX V.....Z2MF 1.6/2.0/3.0 1.0 1.0 1.1MF
Perforated stainless steel sheet reinforcement, 316 (L), 0.1 mm, unbonded
Other dimensions, densities and reinforcements on request *) Foil tapes are available at >_ 4.0 mm width
TALuft
TALuft
TALuft
TALuft
S I G R A F L E X ®
9
MECHANICAL ANDPHYSICAL PROPERTIESOF SIGRAFLEX FOILS
SIGRAFLEX products areavailable with standard bulkdensities of 0.7 to 1.3 g/cm3.The change in bulk density asa function of the pressureapplied in the compressionprocess is shown in Figure 1.Deformation consists of twodistinct components, namely:
• irreversible or plasticdeformation and
• reversible or elasticdeformation.
The curve marked “pressurereduced“ in Figure 1 describesthe irreversible deformation ofSIGRAFLEX FOIL. The differencein density between the linesmarked “pressure applied“ and“pressure reduced“ is due tothe elastic deformation compo -nent. This component is ofoverriding importance in thesealing action of the graphitefoil, for example. As the de -gree of compression rises, theindividual graphite crystals areincreasingly oriented within theplane of the sheet. As a result,the anisotropy of the propertiesbecomes more pronounced:see Figures 2 to 5.
In Table 2, the properties of the high-purity foil F.....10Z areillustrated by way of examplefrom the large number of foiltypes available. A more detaileddescription is given in the datasheet SIGRAFLEX® FOIL.
The thermal stability of graphitefoil has a great impact on thereliability and service life ofseals made of it. Figure 10shows the im proved oxidationresistance of SIGRAFLEX APXfoil compared with commer -cially available graphite grades.
SIGRAFLEX FOIL Characteristic data for a graphite bulk density of 1.0 g/cm3
Table 2
Product type F.....10Z
Permeability coefficient for airthrough plane (DIN 51925) cm2/s < 5 · 10-5
Thermal stability Can be used from -250°Cup to approx. 3000°C(in protective gas)
Sublimation temperature °C > 3000
Ash content (DIN 51903) % <_ 0.15
Chloride content (DIN 28090-2) ppm <_ 10
Tensile strength N/mm2 >_ 4
Elongation at break % >_ 1
Residual stress (DIN 52913) N/mm2 >_ 48
Specific heat (20°C) k J/(kg · K) 0.7
Coefficient of thermal expansion (20 to 1000°C)
in plane 10–6/K approx. 1
through plane 10–6/K approx. 30
Shore hardness (D) approx. 30
Coefficient of friction at 20°C in airagainst steel, peak-to-valley height <_10 µm 0.1
Gasket pressure (N/mm )1
02 5 10 20 50 1000
1.0
1.5
2.0
2.5
Bulk
den
sity
(g/c
m )3
“pressure applied“
1002
500200
“pressure reduced“
Fig. 1:
Bulk density ofSIGRAFLEX with aninitial bulk density of 1.0 g/cm3 as afunction of the gasketpressure applied at a specific time(“pressure applied“)and that appliedpreviously (“pressurereduced“)
S I G R A F L E X ®
10
Temperature (°C) 1000 20000
100
1000
in plane10
Resis
tivity
(Ωμm
)
through plane
Temperature (°C) 1000 20000
100
150
Ther
mal
con
duct
ivity
(W/K
·m)
in plane
50
through plane
Fig. 2:
Resistivity as a function oftemperature, bulk density 1.0 g/cm3
Fig. 3:
Thermalconductivity asa function oftemperature, bulk density 1.0 g/cm3
OTHER PHYSICALPROPERTIES
Bulk density (g/cm ) 3
0.50 1.00 1.500
200
400
600
800
Resis
tivity
(Ωμm
)
through plane
in plane
Bulk density (g/cm3)0.50 1.00 1.500
100
200
300
400
Ther
mal
con
duct
ivity
(W/K
·m)
through plane
in plane
Fig. 4:
Resistivity as a function of bulk density
Fig. 5:
Thermalconductivity as a function of bulk density
S I G R A F L E X ®
11
MECHANICAL ANDPHYSICAL PROPERTIESOF UNREINFORCEDSIGRAFLEX SHEETS
The SIGRAFLEX BASIS sheetscontaining no additives or rein forcements and bearing the designations L.....C andL.....Z have the same propertiesas foils F.....C and F.....Z.Guideline material data onSIGRAFLEX BASIS andSIGRAFLEX STANDARD(impregnated) are contained in Table 3. Impregnated sheetsdiffer from unimpregnatedsheets in having better imper -mea bility, better handlingproperties and antistick surfaces.
Figure 6 shows the compressionbehavior of SIGRAFLEX BASISwith a bulk density of 1.0 g/cm3
and a material thickness of 2.0 mm. A distinction has to be drawn between the curvebranches “under pressure“ (line k) and “after reduction inpressure“ (linies r). Dependingon the pressure applied before -hand, the material recoversalong one of the “r“ lines afterthe pressure is reduced.
Typical levels of recovery are10 % of the residual thicknessafter previous compressivestress (for bulk density of 1.0 g/cm3). If the bulk densityis higher, the percentage re co very decreases.
The “recovery“ is synonymouswith the “elastic deformation“ of the material. The differencebetween the initial thickness ofthe material and its thicknessafter reduction in pressure is its “plastic deformation“. Bothvalues are plotted in Figure 7under conditions of increasinggasket pressure for a materialhaving a bulk density of 1.0 g/cm3 and containing noadditives.
Compared with other sealingmaterials, SIGRAFLEX is soft andrelatively easy to compress. Thisenables the material to adaptwell to the sealing surface, forinstance. Over long serviceperiods SIGRAFLEX displays nonotable changes in its propertiescompared with other sealingmaterials. Figure 8 shows thedecline in gasket pressure invarious sealing materials duringtheir service life. Figure 9 showstypical leakage rate curves ofvarious materials.
Disparities in compression have an effect on the material’simpermeability. The leakagerate declines at high gasketpressure when the installedSIGRAFLEX gaskets have a highbulk density in their compressedstate. One major advantage ofthis material is that the sealingeffect is retained even when thegasket pressure is reduced.
S I G R A F L E X ®
12
Gasket pressure (N/mm )2
2000
10
Com
pres
sibili
ty a
nd re
cove
ry (%
)
1
20
30
40
50
2 5 10 20 50 100
Compressibility
Recovery
Field ofplasticdeformation
Gasket pressure (N/mm )2 1000
k
1.0
Gas
ket t
hick
ness
(mm
) 2.0
10
r1.2
1.4
1.6
1.8
20 30 40 50 60 70 80 90
50
100
60
70
80
90
Thic
knes
s re
lativ
e to
the
initi
al th
ickn
ess
(%) Fig. 6:
Compressioncurve k andrecovery curves r as determined on gaskets*)
Fig. 7:
Recovery as apercentage of theinitial thickness of SIGRAFLEXgaskets*) plottedagainst precedinggasket pressure(plastic defor ma -tion = compres -sibility - recovery)
*) SIGRAFLEX BASIS L20010Z
Unreinforced SIGRAFLEX sheets. Characteristic data for 2.0 mm thick sheets Table 3
Product type
Graphite, bulk density g/cm3
Graphite, ash content (DIN 51903) %Chloride content (DIN 28090-2) ppm
Compression factors (1), (2) (DIN 28090-2)
• Compressibility at 20°C �KSW %• Recovery at 20°C �KRW %• Hot creep during operation �WSW %• Recovery at 300°C �WRW %
Compressibility (ASTM F36A-66) %Recovery (ASTM F36A-66) %
STANDARDL20010CI
1.0<_ 2.0<_ 50
40 to 503 to 5< 4
3 to 4
40 to 5010 to 15
BASISL20010Z
1.0<_ 0.15<_ 20
40 to 503 to 4< 3
3 to 4
40 to 5010 to 15
(1) �KSW Gasket compression set under a pressure of 35 N/mm2
�KRW Gasket recovery after reduction in pressure from 35 N/mm2 to 1 N/mm2
�WSW Gasket creep compression under a pressure of 50 N/mm2 at 300°C after 16 h�WRW Recovery after reduction in pressure from 50 N/mm2 to 1 N/mm2
The percentage changes in thickness of �KSW, �KRW, �WSW and �WRW are relative to the initial thickness of the gasket
(2) Gasket factors in accordance with DIN E 2505, DIN 28090, DIN 52913 and DIN EN 13555 for the various sheet materials can be found in our separate product data sheets
S I G R A F L E X ®
13
Duration of test (h)
Leak
age
rate
l
10
Flexible graphite (200°C)
1 100 1000 10 000
Elastomer-bondedfiber gasket (200°C)
Standard PTFE (150°C)
Fig. 9:
Change in the leakage rate of varioussealing materials in long-term testing,measured in accordance with DIN 28090-1 and -2 in flange PN 40DN 40. The testing temperature for thismaterial was set at only 150°C owingto the hot flow of PTFE
Fig. 10:
Comparison between the thermalstability of a commercially availablegraphite foil and that of SIGRAFLEXAPX foil with advanced oxidationresistance
Duration of test (h)
0
Gas
ket p
ress
ure
(%)
10
Flexible graphite (200°C)
20
40
60
80
100
1 100 1000 10 000
Elastomer-bonded fiber gasket (200°C)
Standard PTFE (150°C)
Fig. 8:
Change in the gasket pressure ofvarious sealing materials during long-term testing, measured in accordancewith DIN 28090-1 in flange PN 40DN 40. The testing temperature for this material was set at only 150°C. The flexible graphite retains its highresidual stress even after exposure toload for approximately 1 year
Temperature in °C
Mas
s lo
ss in
air
(%/h
)
Commercially available grade
APX grade
Type: F05010Ash content: ≤ 2 %
~150°C
400 500 600 700 8000.001
0.01
0.1
1
10
100
S I G R A F L E X ®
14
MECHANICAL ANDPHYSICAL PROPERTIESOF REINFORCEDSIGRAFLEX SHEETS
Reinforced sheets of variousversions are illustrated in Figure14. Typical data on these sheetsare compared in Table 4. Theminimum requirements specifiedin DIN 28091-4 are surpassedby sheets with metal reinforce -ment. Detailed particulars aregiven in the relevant data sheets.The maximum permissible gasketpressures on reinforced sheetsare illustrated in Figure 13.With gaskets it is important tonote the width-to-thickness ratio;as it increases, so too does themaximum permitted pressure.The curves shown by way ofexample are for materials 2 mmthick.
Figure 11 shows the typicalcom pressibility and recovery of SIGRAFLEX HOCHDRUCK for reinforced sheet types in comparison with those ofunreinforced sheets.
SIGRAFLEX has an extra -ordinary stability in vibratingmachinery. This is illustrated by the following example:A gasket pressure of 50 N/mm2
reduces the initial thickness ofSIGRAFLEX UNIVERSAL byabout 60 %. After this pre limi -nary stress the material issubjected to vibrating stressesranging from 10 to 50 N/mm2.Its power of recovery is retainedeven after 107 stress alternationcycles, when no more than very slight creep compression is observed (see Figure 12).
Gasket pressure (N/mm )2100 2000
k
1.1
Gas
ket t
hick
ness
(mm
)
1.2
1.3
1.4
1.5
1.6
1.7
1.8
1.9
2.0
1.050 150
r
r
j
Fig. 11:
Compression curve k and variousrecovery curves r as determined ongaskets fabricated from SIGRAFLEX HOCHDRUCK V20011Z3I.For purposes of comparison, thecompression line j for SIGRAFLEX BASISis included from Figure 6
Fig. 13:
Max. permissible gasket pressure forgaskets made from reinforcedSIGRAFLEX sheets of 2 mm thickness,as determined at 300°C in accordancewith DIN 28090-1
Max
. per
miss
ible
gas
ket p
ress
ure
@N/m
m2 #
Width-thickness ratio
50
100
150
200
250
300
0 2 4 6 8 10 12 14
SIGRAFLEXSELECT
SIGRAFLEX MF
SIGRAFLEX UNIVERSALSIGRAFLEX UNIVERSAL PRO
SIGRAFLEX HOCHDRUCKSIGRAFLEX HOCHDRUCK PRO
Graphite gasket with high adhesive and /or binder content
Number of stress cycles 100
Recovery
0
60
65
70
Resid
ual t
hick
ness
as
a pe
rcen
tage
of i
nitia
l thi
ckne
ss
102 104 106 108
stress reduced to 10 N/mm2
stress increased to 50 N/mm2
Stress cycles
f = 50 Hzs max = 50 N/mm2
s min = 10 N/mm2
Fig. 12:
Behavior ofSIGRAFLEXUNIVERSAL undervibrating stress
S I G R A F L E X ®
15
Fig. 14:
Sketches showingthe construction ofsheets reinforcedwith metal foils
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SIGRAFLEX HOCHDRUCKHigh-integrity multilayer laminate,impregnated graphite, s/s foilsSIGRAFLEX HOCHDRUCK PROalso for applications subject to TA Luft
SIGRAFLEX MFHigh-integrity laminate made ofgraphite, stainless steel and PTFE; max. requirements for sealability (TA Luft), safety, chemical resistance and process hygiene
SIGRAFLEX ECONOMYReinforced with bonded s/s foil
SIGRAFLEX SELECTHigh-integrity s/s foil reinforcement,impregnated gasket with inner eyeletfor applications subject to the German TA Luft (Clean Air Act)
SIGRAFLEX UNIVERSALPerforated s/s sheet reinforcement,impregnatedSIGRAFLEX UNIVERSAL PROalso for applications subject to the German TA Luft (Clean Air Act)
The flexible graphite is shown in white color.The metal foilsare shown ashatched surfaces.The PTFE foils areshown as dottedsurfaces.
S I G R A F L E X ®
16
Reinforced SIGRAFLEX sheets. Characteristic data for 2.0 mm thick sheets*)
Product type
Graphite, bulk density g/cm3
Graphite, ash content (DIN 51903) %Chloride content (DIN 28090-2) ppm
Reinforcing sheet, numberReinforcing sheet, thickness mmReinforcing sheet, type
Reinforcing sheet, ASTM material no.
Compression factors (1), (2) (DIN 28090-2)
• Compressibilty at 20°C �KSW %• Recovery at 20°C �KRW %• Hot dreep during operation �WSW %• Recovery at 300°C �WRW %
Compressibility (ASTM F36A-66) %Recovery (ASTM F36A-66) %
ECONOMYV20010C4
1.0<_ 2.0<_ 50
10.05
smooth
316(L)
35 to 453.5 to 4.5
< 53 to 4
40 to 5010 to 15
UNIVERSALV20010C2IUNIVERSAL
PROV20010C2I-P
1.0<_ 2.0<_ 50
10.1
perforated
316(L)
35 to 454 to 6< 5
3 to 6
30 to 4515 to 25
SELECTV16010C3I
1.0<_ 2.0<_ 50
20.05
smooth
316(L)
30 to 403 to 5< 2
2 to 4
30 to 4010 to 15
HOCHDRUCKV20011Z3I
HOCHDRUCKPRO
V20011Z3I-P
1.1<_ 0.15<_ 20
30.05
smooth
316(L)
30 to 404 to 5< 4
3 to 4
30 to 4015 to 20
MFV20011Z2MF
1.1<_ 0.15<_ 20
10.1
perforated
316(L)
25 to 353 to 5< 4
3 to 5
25 to 3515 to 20
(1) �KSW Gasket compression set under a pressure of 35 N/mm2
�KRW Gasket recovery after reduction in pressure from 35 N/mm2 to 1 N/mm2
�WSW Gasket creep compression under a pressure of 50 N/mm2 at 300°C after 16 h�WRW Recovery after reduction in pressure from 50 N/mm2 to 1 N/mm2
The percentage changes in thickness of �KSW, �KRW, �WSW and �WRW are relative to the initial thickness of the gasket(2) Gasket factors in accordance with DIN E 2505, DIN 28090, DIN 52913 and DIN EN13555 for the various sheet materials
can be found in our separate product data sheets*) SIGRAFLEX SELECT in 1.6 mm thickness
Table 4
S I G R A F L E X ®
17
The technical world we live in isgrowing increasingly complex.To minimize risks, standards arebeing agreed on both nationaland international levels andstatutory regulations issued.
For many years our materialshave been subjected to wide-ranging tests as specified in the current regulations. Therespective product reports,approvals and certificates arelisted below. SIGRAFLEXmaterials comply with manydifferent standards and statutory regulations. Thisrepresents a safeguard for our customers.
• BAM1) reports on testsconducted to determinereactivity with gaseous and liquid oxygen. SIGRAFLEX FOILSIGRAFLEX STANDARD SIGRAFLEX ECONOMYSIGRAFLEX UNIVERSALSIGRAFLEX UNIVERSALPROSIGRAFLEX SELECTSIGRAFLEX HOCHDRUCKSIGRAFLEX HOCHDRUCKPROSIGRAFLEX MF
• BAM reportson tests conducted todetermine the chemicalstability of ethylene oxide and propylene oxide.SIGRAFLEX UNIVERSALSIGRAFLEX HOCHDRUCK
• Blow-out resistance (TÜV)SIGRAFLEX UNIVERSALSIGRAFLEX UNIVERSALPROSIGRAFLEX SELECTSIGRAFLEX HOCHDRUCKSIGRAFLEX HOCHDRUCKPROSIGRAFLEX MF
• DVGW2) registration reports for gas supplySIGRAFLEX FOILSIGRAFLEX STANDARDSIGRAFLEX ECONOMYSIGRAFLEX UNIVERSALSIGRAFLEX UNIVERSALPROSIGRAFLEX SELECTSIGRAFLEX HOCHDRUCKSIGRAFLEX HOCHDRUCKPROSIGRAFLEX MF
• DVGW test certificates fordrinking waterin accordance with KTW3)
SIGRAFLEX FOILSIGRAFLEX STANDARD
• Fire safety (API 607 and/or BS 6755-2)SIGRAFLEX UNIVERSALSIGRAFLEX UNIVERSALPROSIGRAFLEX SELECTSIGRAFLEX HOCHDRUCKSIGRAFLEX HOCHDRUCKPROSIGRAFLEX MF
• Germanischer LloydSIGRAFLEX UNIVERSALSIGRAFLEX HOCHDRUCK
• TA Luft (VDI 2440)(German Clean Air Act)SIGRAFLEX UNIVERSALPROSIGRAFLEX SELECTSIGRAFLEX HOCHDRUCK*)
SIGRAFLEX HOCHDRUCKPROSIGRAFLEX MF
• Test report of the Baden-Württemberg Department of IndustryOffice for Chemical andTechnical Testing: Contact ofSIGRAFLEX graphite foil withfoodstuffs
• TRD 401 (manhole gaskets)SIGRAFLEX HOCHDRUCK
• United States Coast GuardSIGRAFLEX UNIVERSALSIGRAFLEX HOCHDRUCK
1) BAM = Bundesanstalt für Ma terial prüfung (Federal Institute for Materials Testing), Berlin
2) DVGW = Deutscher Verein der Gas- und Wasserfachmänner(German Association of Gas andWater Operatives)
3) KTW = Kunststoff-Trinkwasser -empfehlung des Bundesgesundheits -ministeriums (Federal GermanMinistry of Health recommendationfor max. levels of plastics in drinkingwater)
*) For raised-face flanges with inner eyelet, for tonque-and-groove flanges without inner eyelet
APPROVALS ANDCERTIFICATES
S I G R A F L E X ®
18
CHEMICAL RESISTANCE OFSIGRAFLEX
Based on natural graphite,SIGRAFLEX products areresistant to most media up tohigh temperatures.
Unreinforced SIGRAFLEX isresistant to inorganic andorganic acids and bases,solvents, waxes and oils, butnot to agents with a powerfuloxidizing action, such as highly concentrated nitric acid,highly concentrated sulfuricacid (oleum), nitrating acid and chloric acid, or molten saltswith a powerful oxidizingaction. Where no details ofconcentration and temperaturesare given for the media listed, it can be assumed that theconcentration is 100 % andthat the temperature is boilingpoint or melting point.
The data given in Table 5should always be checked bythe user since the limits to theuse of SIGRAFLEX seals alsodepend on the design features,internal pressure, temperatureand the gasket pressure.Resistance to highly aggressivesubstances not listed needs tobe ascertained. SIGRAFLEXusers should request advicefrom us in such circumstances.
The resistance of reinforcedSIGRAFLEX gaskets is usuallygoverned by the reinforcingmetal sheets or foils used.Table 5 makes no reference tothe stability values for steel orPTFE. The stainless steel withASTM material no. 316 (L)used in unbonded SIGRAFLEXsheets (UNIVERSAL, UNIVERSALPRO, SELECT, HOCHDRUCK, HOCHDRUCKPRO and EMAIL)has proved very successful inthe chemical industry becauseof its good stability. Uponrequest we also provide a listof chemical media showing the resistance of graphite foil,stainless steel and PTFE. Onbonded sheets (ECONOMY)particular attention must bepaid to the stability of the ad -hesive, especially at elevatedtem peratures.
As is the case with other gas ket materials, it is essentialfor chemical stability tests onSIGRAFLEX to be carried outwith the material in a com press - ed state (see DIN 28090-3).
S I G R A F L E X ®
19
Table 5Chemical resistance of SIGRAFLEX FOIL (pure graphite)***)
Alcohols
e.g. � Ethyl alcohol� Glycol� Isopropyl alcohol� Methyl alcohol
Aldehydes
e.g. � Acetaldehyde� Benzaldehyde� Formaldehyde
Ethers
e.g. � Diethyl ether� Dioxane� Diphenyl ether� Methyl ethyl ether
Esters
e.g. � Acetic acid amyl ester� Acrylic acid ethyl ester� Ethyl butyl ester
Amines
e.g. � Aniline� Diethylamine� Triethylaminoethanol
Oxidizing molten salts
� Potassium chlorate� Potassium nitrate� Sodium peroxide
Ketones
e.g. � Acetone� Ethyl methyl ketone� Methyl isobutyl ketone
Hydrocarbons
e.g. � Benzene� Ethylene� Iso-octane� Propane� Propylene� Styrene� Xylene
Alkalis
e.g. � Ammonia solution� Caustic potash solution� Caustic soda solution� Potassium hydroxide up to
400°C� Sodium hydroxide up to
400°C
Other inorganic media
� Bleach liquor� Hydrazine� Sulfur
Technical mixtures
e.g. � Heat transfer oils� Hydraulic oils� Motor oils� Paint thinner� Paraffin oil (kerosene)� Petrol (gasoline)� Transformer oil
Other organic media
e.g. � Acrylonitrile� Carbon disulfide� Dimethyl sulfoxide� Epichlorohydrine� Mercaptans� Nitrobenzene� Phenol� Silicones� Siloxanes� Thionyl chloride
� Potassium up to 350°C� Silver� Tin� Wood’s alloy� Zinc
Organic acids
e.g. � Acetic acid� Acrylic acid� Formic acid� Hexachlorphenyl acetic
acid� Maleic acid� Monochloroacetic acid� Phenylacetic acid� Phthalic acid� Stearic acid� Sulfonic acid� Tartaric acid� Trichloroacetic acid
Acids
e.g. � Aqua regia� Boric acid� Bromic acid� Chromosulfuric acid
up to 20 %� Hydrochloric acid � Hydrofluoric acid� Nitrating acid� Nitric acid
up to 65 %� Nitric acid
> 65 %� Oleum� Perchloric acid
up to 20 % � Phosphoric acid� Sulfuric acid
up to 70 %� Sulfuric acid
70-100 %up to 100°C
� Sulfurous acid
Gases/vapors
e.g. � Air, at more than 400°Csubject to prior consultation
� Ammonia� Bromine� Carbon dioxide up to
approx. 600°C� Carbon monoxide� Chlorine dioxide� Chlorine, dry� Chlorine, moist at > 30°C� Fluorine� Hydrogen bromide� Hydrogen chloride� Hydrogen fluoride� Hydrogen sulfide� Nitrogen� Nitrogen dioxide up to
approx. 600°C**)
� Nitrous oxide**)
� Oxygen up to approx.350°C
� Phosgene� Sulfur dioxide� Sulfur hexafluoride� Sulfur trioxide
Aqueous salt solutions
e.g. � Borates� Bromides� Carbonates� Chlorides� Chromates,
20 % conc.� Fluorides� Iodides� Nitrates� Nitrites� Phosphates� Sulfates
Metal melts
e.g. � Aluminum� Copper� Gold� Iron� Lead� Magnesium� Mercury
Halogenated hydrocarbons
e.g. � Carbon tetrachloride� Chlorobenzene� Chloroform� Frigen products
Non-oxidizing molten salts
� Borate, soda, potash � Calcium chloride� Potassium hydrogen sulfate
� resistant� not resistant� reservedly resistant
*) without oxygen ingress**) dry gases only***) The resistance of
reinforced SIGRAFLEXgaskets can be check edin our TechnicalInformation “SIGRAFLEXGaskets – Resistance toChemical Media”
S I G R A F L E X ®
20
Seals and Sheetsmade fromSIGRAFLEX®
Technical Trader
SIGRAFLEX®
FoilsSheetsSealings
Seals and Sheets made fromSIGRAFLEX®
LegislationStandardization
Regulation
SealManufacturer
WholesaleTrader
MARKET APPROACH AND CUSTOMER SERVICE
R & DTest Facilities
Product Quality
Product Availability
Customer Service
Technical Support & Advice
Training
END USERS AND PLANT CONTRACTORS IN THE PROCESS INDUSTRIES:
Chemical and Petrochemical Industries,Power Stations, Pulp & Paper, Gas, Machine Construction
Expanded Graphite
S I G R A F L E X ®
21
OUR EXPERTISE IS YOUR ADVANTAGE
High Performance and Safety in Sealing Systems
Our Expertise
Analytical Lab• R & D in sealing systems• Comprehensive seal testing• Continuous product
improvement
Excellent Product Quality• Selected raw materials • Low leakage rates• High blow-out resistance• Superior oxidation resistance• Fire safety
Worldwide Product Availability• Available from stock
in various dimensions • For universal use over a
wide range of applications
Service• Technical support in sealing
selection and installation• Training on fluid sealing-
related issues • Worldwide sales offices• Advice on seal design
and calculation
Your Advantage
• Outstanding productreliability
• Long service life
• Skilled maintenance staff
• Less downtimes
• Saving of resources
• Reduced total costs of ownership
� EnvironmentalProtection
� Safety and PlantAvailability
� Cost Savings
Enhances
S I G R A F L E X ®
22
PROCESSING OFSIGRAFLEX FOILS
Our semi-finished SIGRAFLEXproducts are processed invarious branches of industryinto a wide variety of seals and other components by the
techniques summarized below.The soft material is easy topunch and cut with standardtools.
Packing rings
Crinkle tapes
Spiral-wound graphite gaskets
Gaskets
Graphite outer layers forKammprofile gaskets
ElectrodesHeating elementsLinings
Self-adhesive gaskets
Universalsealing tapes,self-adhesive
Foil tapes
Cutting
Cutting andcorrugating
Windingandpressing
Crinkling
Winding
Punching
Punching andbonding
Cutting andpunching
Punching
SIGRAFLEX foils
SIGRAFLEX self-adhesive foil withrelease paper
Coating
Semi-finished product Processing technique End product
S I G R A F L E X ®
23
PROCESSING OFSIGRAFLEX SHEETS
Simple gaskets
Smooth stainless steel ring gas -kets with graphite outer layers
Corrugated stainless steel ringgaskets with graphite outerlayers
Gaskets for pumps and fittings
Gaskets for pipeworkUNIVERSAL PRO: Forapplications subject to theGerman TA Luft (Clean Air Act)
Gaskets with s/s inner eyeletsfor raised-face flanges, inapplications subject to theGerman TA Luft (Clean Air Act)
High-quality gasketswith metal eyelets for universal applicationsHOCHDRUCK PRO: Forapplications subject to theGerman TA Luft (Clean Air Act)
Superior-quality gaskets with s/s inner eyelets for maximum sealability and safety
Unr
einf
orce
d sh
eets
Rein
forc
ed s
heet
s
Typi
cal
gask
et s
ectio
ns
SIGRAFLEX product Processing technique End product
Typi
cal
gask
et s
ectio
n
SIGRAFLEX BASIS +SIGRAFLEX STANDARD
SIGRAFLEX SELECT
SIGRAFLEX ECONOMY
SIGRAFLEX UNIVERSALSIGRAFLEX UNIVERSAL PRO
SIGRAFLEX HOCHDRUCKSIGRAFLEX HOCHDRUCK PRO
The flexible graphite is shown in white color. The metal foils are shown as hatched surfaces. The PTFE foils are shown as dotted surfaces
PunchingCuttingScarf cuttingBonding
PunchingCutting
PunchingCuttingScarf cuttingBonding
PunchingCuttingScarf cuttingBonding
PunchingCuttingScarf cuttingBonding
SIGRAFLEX MF
PunchingCutting
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S I G R A F L E X ®
24
ADVICE ONAPPLICATION FORSTUFFING BOXPACKINGS
Key words
Maintenance
Shaft wear
Friction coefficients
Packing height
Packing structure
Leakage rate
Heat dissipation
Fire safety test
Results of using SIGRAFLEX in practical situations
Low maintenance expenditure due to longservice life and hence short downtimes.
Low; SIGRAFLEX is soft and self-lubricating.
Between 0.08 and 0.25 against steel withsliding speeds of up to 30 m/sec and in thepresence of small quantities of moisture.
Low, owing to high density. Individual rings canbe subsequently added to a packing if the glandcannot be tightened further.
Marked improvement in service behaviorobtained with braided carbon fiber packingrings.
Low, even with short packings and high pressuredifferentials.
Very good owing to high thermal conductivityup to 400 W/(K·m).
Fittings with packings manufactured by ourcustomers from SIGRAFLEX material have provedsatisfactory in this test.
S I G R A F L E X ®
25
ADVICE ONAPPLICATION FORGASKETS
Key words
Gasket pressure
Maximum gasket pressure
Bolt forces
Service pressure
Cold and warm flow
Service lives
Microsealing andmacrosealing
Leaking flange joint
Fire safety test
Gaskets of large andcomplicated design
Release agents
Wet or moisture
Dismantling
Disposal
Results of using SIGRAFLEX in practical situations
Owing to their high compressibility, SIGRAFLEXgaskets are useful for sensitive and/or unevenflanges, e.g. those made of glass, enamel orgraphite. The homogeneous distribution of thegasket pressures ensures an optimum sealing effect.
High gasket pressures are permissible even at hightemperatures. The selected SIGRAFLEX type shouldbe suitable for the specified width-thickness ratio.
As a rule, the bolt forces should be used to the full.
Very high service pressures can be accommodatedreliably by using a properly selected SIGRAFLEXtype (e.g. HOCHDRUCK).
None detected up to maximum permissible gasket pressure; hence no need for retightening the bolts while plant or equipment is in use.
Very high in comparison with conventional material(e.g. longer lives due to very good oxidationresistance).
SIGRAFLEX adapts very well to ultrafine or coarsesurface irregularities. Hence, no special demandsneed be imposed on the flange surfaces.
In the case of liquids, never retighten flange bolts – always replace the gasket.
BS 6755-2 and API 607 certificates have been issued for a number of high-qualitySIGRAFLEX materials.
Can be assembled from segments.
Never pretreat gaskets with oil or grease.
Moist gaskets must not be fitted (drying allowed).
SIGRAFLEX gaskets are easy to remove and involve no health risk.
Uncontaminated material can be disposed ofwithout any problems.
S I G R A F L E X ®
26
SIGRAFLEX type
STANDARD
ECONOMY
UNIVERSALUNIVERSAL PRO
HOCHDRUCKHOCHDRUCK PRO
Unreinforced,impregnated
Reinforced withperforated s/s sheet,impregnated
High-integritymultilayerlaminate,impregnated,reinforced with s/s foil
PTFE-envelopegasket withSIGRAFLEX EMAILcore
Reinforced withbonded stainlesssteel foil
Cross-section Characteristics
High-quality SIGRAFLEX gasket systems and fields of application
Field of application
Glass/enamelled flanges,complicated designs, highlycorrosive media (e.g. HCI)
Gas technology; pumps and fittings; offshore
For pipework and vessels in thechemical and petro chemicalindustries and in power stations;UNIVERSAL PRO: For appli -cations subject to the GermanTA Luft (Clean Air Act)
Universal problem-solvinggasket material for the processindustries to meet demandingrequirements for sealability andsafety (e.g. tongue-and-grooveflanges); ease of pro cessingand assem bly. HOCHDRUCKPRO: For applications subjectto the German TA Luft (CleanAir Act)
MF High-integritylaminate made of graphite,stainless steel and PTFE
Maximum requirements forsealability, safety, chemicalresistance and process hygiene; sealed joints in thechemical, petro chemical,pharmaceutical and foodindustries
SELECT High-integrity s/s foilreinforcement,impregnated
For applications subject to theGerman TA Luft (Clean AirAct); raised-face flanges;pipework in the chemical andpetrochemical industries
For enamelled flanges,exacting demands for seal -ability and process hygiene in the pharmaceuticalindustry, aggressive media
Table 6
S I G R A F L E X ®
27
Exhaust systemsCylinder-head gasketsStandard flangesTongue-and-groove flangesVessel/equipment flangesGaskets up to 1500 mm diam.Glass/plastic/enamel surfacesHighly corrosive media*)
High gasket pressuresMechanical shear movements
Fittings Vessels/equipmentPipeworkInspection glassesWaste gas purification
recommendedsuitable**)
*) to which the metal reinforcements (ASTM material no. 316 (L)) are not resistant**) each individual case needs to be considered separately
Table 7 Recommended SIGRAFLEX products for various applications
TA LuftAutomotiveindustryChemical industry
Gas technologyPower stationtechnology
Engine buildingFood industryWater supply
ProductsComponentsIndustries
SIG
RAFL
EX S
TAN
DA
RD
SIG
RAFL
EX E
CO
NO
MY
SIG
RAFL
EX U
NIV
ERSA
LSI
GRA
FLEX
UN
IVER
SALPRO
SIG
RAFL
EX S
ELEC
T
SIG
RAFL
EX H
OC
HD
RUC
KSI
GRA
FLEX
HO
CH
DRU
CKPRO
SIG
RAFL
EX M
F
SIG
RAFL
EX E
MA
ILin
PTF
E en
velo
pes
S I G R A F L E X ®
28
Weight Units
1kg = 2.2046 lb = 35.274 oz1lb = 16 oz = 0.45359 kg
COMMONLY USEDCONVERSION FACTORS
mmcmminchfootyard
mm
110100025.4304.8914.4
cm
0.111002.5430.4891.44
m
1·10–3
0.0110.02540.30480.914
inch
0.03940.393739.3711236
foot
3.281·10–3
0.032813.2810.083313
yard
1.094·10–3
1.094·10–2
1.0942778·10–2
0.331
Units of Length
mm2
cm2
m2
inch2
foot2
yard2
mm2
1102
106
645.29.29·10–4
8.36·105
cm2
10–2
1104
6.4529298.36·103
m2
10–6
10–4
16.452·10–4
9.29·10–2
0.836
inch2
1.55·10–3
0.155155011441296
foot2
1.076·10–5
1.076·10–3
10.7646.94·10–3
19.009
yard2
1.196·10–6
1.196·10–4
1.1967.716·10–4
0.1111
Units of Area
Units of Volume
cm3
literm3
inch3
foot3
gallon
cm3
11000105
16.392.83·104
3785
liter
10–3
110000.0163928.323.785
m3
10–6
0.00111.64·10–5
0.028323.785·10–3
inch3
0.0610261.026.1·104
11728231
foot3
3.53·10–5
0.0353235.325.79·10–4
10.1337
gallon
2.64·10–4
0.2642264.24.33·10–3
7.4811
S I G R A F L E X ®
29
l/sgal/minft3/sft3/min
l/s
10.063128.320.4719
gal/min
15.851448.87.481
ft3/s
0.035320.0022310.01667
ft3/min
2.1190.1337601
Units of Force
Units of Pressure and Stress
Units of Density
1 kg/l = 1g/cm3 = 62.42 lb/ft3 = 9271.1 lb/in3
1 lb/ft3 = 5.787·10-4 lb/in3 = 0.01602 g/cm3
1 lb/in3 = 1728 lb/ft3 = 107.86 g/cm3
1 N/m2 = 1 Pa = 10-6 N/mm2 = 1.45037·10-4 lbf/in2 (psi)1 MPa = 1 N/mm2 = 10.2 bar = 145.037 lbf/in2 (psi)
1 bar = 760 mm Hg = 29.92 inch Hg = 14.5 psi
1 psi = 144 lbf/ft2 = 6.895 kPa = 6.895·10-3 N/mm2
= 6.895·103 N/m2 = 6.895·10-2 bar1 mm Hg = 0.03937 inch Hg = 0.01934 psi = 0.001315 bar1 inch Hg = 0.4912 psi = 1.133 ft water
1 N = 0.2248 lbf1 lbf = 4.448 N
Units of Energy, Moment
Units of Flow Rate
1 Ws = Nm = 1 Joule = 0.948 BTU = 0.738 lbf · ft1 lbf · ft = 1.356 Nm = 1.3558 Joule = 1.285 BTU
COMMONLY USEDCONVERSION FACTORS
S I G R A F L E X ®
30
Units of Temperature
Units of Thermal Conductivity
tC = 5/9(tF - 32) °C tF = (1.8·tC) + 32 °F
1 BTU/(hr °F) · ft2/ft = 1.731 W/(K·m) 1 W/(K·m) = 0.578 BTU/(hr °F) · ft2/ft
Unit of Resistivity
1 Ohm in = 25.4 · 103 Ohm µm 1 Ohm µm = 39.4·10–6 Ohm in
Units of Gas Permeability
Gas permeability (DIN 3535-4): ___ in ___
Gas permeability (DIN 28090-1): �= ___ _____ in ___
Conversion DIN 3535 into DIN 28090: 1= ___ = 0.094 ____
� in mg/cm3 Density of test gas under normal conditionsdD in m Mean efficient gasket diameter (0.07 m)
Conversion of leakage rates for nitrogen:1 mbar·l/s = 1.19 mg/s = 0.952 cm3/s = 57.12 cm3/min
tV
tV
s·mmg
s·mmg
mincm3
mincm3
�·dD
�
°C
-100- 90- 80- 70- 60- 50- 40- 30- 20- 10
°F
-148-130-112- 94- 76- 58- 40- 22- 4
14
°C
010203040506070809
°F
32506886
104122140158176194
°C
100110120130140150160170180190
°F
212230248266284302320338356374
°C
200250300350400450500550600
1000
°F
392482572662752842932
102211121832
·
COMMONLY USEDCONVERSION FACTORS
S I G R A F L E X ®
31
DEFINITIONS OF GASKET FACTORS
Definitions of gasket factors used in old and new regulations
bD
bD bD�
DIN EN 13555 DIN 28090 Explanation
QMIN(L) �VU/L Minimum level of surface pressure required for leakage rate class L on assembly [MPa]
�BU Minimum gasket pressure under serviceconditions, where �BU is the product of internalpressure p and gasket factor m for test and service conditions [�BU = p · m]
QS MIN(L) �BU/L Minimum level of surface pressure rate class Lafter off-loading [MPa]
QS MAX �BO Maximum surface pressure that can be safely imposed upon the gasket at service temperature without damage [MPa]
�VO Maximum permissible gasket pressure at RT [MPa]EG Secant unloading modulus of the gasket [MPa] PQR Ratio of gasket surface pressure before and
after relaxationLN LN Leakage rate class – subscript N indicates the
max. specific leakage rate for that leakage rate class [mg s-1 m-1]
The definitions of the older gasket factors (DIN V 2505 of 1964, AD Merkblatt B7of 1977) are as follows:
k0 in mm Factor for gasket assembly pressurek1 in mm Factor for gasket pressure under
service conditions k2 in mm Factor for max. stress-bearing capacity under
service conditionsKD in N/mm2 Max. gasket stress-bearing capacity under
assembly conditionsKD� in N/mm2 Creep strength under compressive stress at
service temperaturebD in mm Gasket width
The following conversion formulas are used:
�VU = Qmin = k0 ·KD
m = k1 / bD
�VO = Qmax = V k0 ·KD
�BO = Qmax = V k2 ·KD�
Graphite Specialties
SGL CARBON GmbH
Werner-von-Siemens-Straße 1886405 Meitingen/GermanyPhone +49 8271 83-2276Fax +49 8271 83-2419expandedgraphite@sglcarbon.dewww.sigraflex.eu
www.sglgroup.com
® registered trademark of SGL Group companies 01 2011/0 8NÄ Printed in Germany
This information is based on our present state of knowledge and is intended to provide general notes on our products and their uses. It should therefore not be construed as guaranteeing specific properties of the products described or their suitability for a particular application. Any exis tingindustrial property rights must be observed. The quality of our products is guaranteed under our “General Conditions of Sale“.
Recommended