Broad Base. Best Solutions.

Specialty Graphites for the Automotive Industry

GrAphITe MATerIALS AnD SySTeMS

22

Specialty Graphite and Process Solutions – made by SGL Group.

ʈ Advanced material, equipment, and process solutions

ʈ Engineered for customers from more than 35 industries

ʈ Tailor-made from the most comprehensive product portfolio

ʈ In-depth production and material knowledge

ʈ Consistent high quality, performance, and service

ʈ Attractive total cost of ownership

Broad Base. Best Solutions.

3BuSIneSS unIT GrAphITe MATerIALS AnD SySTeMS

r Axial seal rings in PTS technology

Advanced solutions enable our customers to get ahead.SGL Group offers advanced solutions – even for challenging applications. We understand the specific requirements of our customers and combine in-depth production, material, and engineering knowledge with the most comprehensive specialty graphite portfolio. This makes us the partner of choice to leading companies in many different industries.

Exceptional resistance to heat and corrosion, high purity and mechanical strength are just a few of the outstanding properties which our materials offer. Specialty graphite products from SGL Group achieve optimal results where other materials fail. No matter what your specific requirements might be, we will identify the best solution from the most comprehensive range of specialty graphites.

ʈ Fine grain graphite: isostatic, vibration- molded, die-molded, extruded

ʈ Expanded natural graphite ʈ Carbon fiber-reinforced carbon (C/C) ʈ Soft and rigid graphite felts ʈ Silicon carbide-coated graphite materials

Additionally we use other materials like PTFE, silicon carbide, and specialty metals.

With our portfolio and technical know-how spanning more than 35 different industries, we engineer tailor-made solutions in close partnership with our customers.

SGL Group covers the entire value chain of specialty graphite production, including raw material processing, semi-finished product manufacture, precision machining, purification, and coating. When it comes to engineering of equipment and process solutions our service range makes the difference: We offer mechanical and process design, production, assembly, commis-sioning, and service – all from a one-stop shop.

This is how we control and ensure the consistent high quality, reliability, and performance of our products – and enable our customers to become more competitive. Challenge us. We are there for you worldwide.

Specialty graphite solutions for the automotive industry Specialty graphites are becoming increasingly important in automobile production. Carbon and graphite materials come into play wherever energy efficiency, environmental compatibility and safety are called for. Our innovative products and special solutions make us a sought-after partner of leading companies.

4

Specialty graphites – made by SGL Group.Solutions for the automotive industry.

Emission control Fuel/water pumps

Typical applications Exhaust gas recirculation valves Electric fuel pumps Exhaust gas recirculation coolers Electric water pumps

Materials made of SIGRAFINE® SIGRAFINE® carbon and graphite die-molded carbon and graphite die-molded carbon and graphite SIGRAFLEX® flexible graphite

Products Bearings Seal ringsof the SGL Group Graphite foils Bearings Commutator discs

SIGRAFINE® is the new brand name for our fine-grain graphites, previously known

under the names RINGSDORFF®, SIGRAFORM®, SIGRAMENT® and CRYSTA-SIL®.

5

Our multifaceted materials distinguish themselves with their exceptional properties and meet stringent requirements for reliability, robustness and lifetime. From thermal management to brake assist pumps, from emission control management to electric pumps: our products increase the performance of systems and processes in countless applications.

For our automotive customers, everything is about future-oriented, environmentally friendly mobility. As demands for CO2 reduction, energy efficiency and driving safety increase, the requirements for components and systems increase right along with them. SGL Group is proud to be able to accompany the ground-breaking developments in the automotive industry with its innovative, high-performance materials and products.

Gaskets Electric brake assist pumps

Mechanical seals for cooling water pumps Electric vacuum pumpsCylinder head gaskets Turbocharger gasketsDiesel particulate filtersVarious elastomer/polymer gaskets

SIGRAFINE® SIGRAFINE®die-molded, isostatic carbon and graphite die-molded, isostatic carbon and graphiteSIGRAFLEX® flexible graphite

Seal rings RotorsGraphite foils Vanes Powder

SpeCIALTy GrAphITe SoLuTIonS For The AuToMoTIVe InDuSTry

6

Specialty graphites for the automotive industry Especially in high-temperature applications, our specialty graphite products can show one of their particular strengths: high oxidation resistance. And the advantages don’t stop there:

Q Good self-lubricating properties for reduced friction and greater energy efficiency

Q Exceptional resistance to chemical media

Q High mechanical strength

7

Sustainability in the automotive industry is directly tied to emission reduction. Intelligent exhaust gas recirculation systems make an important contribution towards protecting our environment. They reduce the formation of nitrogen oxides, help keep fuel consumption down and are built into almost every single vehicle today.

SGL Group supplies high-performance bearings made of carbon, carbon graphite1⁾ and expanded graphite for exhaust gas recirculation systems. These materials are extremely resistant to high temperatures and aggressive gases. They also possess excellent sliding properties for low-wear, and low-noise running.

c Graphite bearings made of flexible graphite and synthetic graphite for EGR applications

SpeCIALTy GrAphITeS For The AuToMoTIVe InDuSTry

Specialty graphites for exhaust applications

b Cooling water pump with carbon seal ring

Application-specific products for exhaust gas recirculation systems (EGR)

Applications ProductsSIGRAFINE SIGRAFLEX

V2142 V2064 EK23 APX2 APEGR valves Bearings ○ ○ ○ ○EGR gaskets Seal rings ○ ○Exhaust manifold Seal rings ○ ○

1) a pitch-bonded, carbonized material with high graphite filler content

8

Water and fuel supply within the vehicle must function reliably, safely and only if required. Extended resistance to media is of utmost impor-tance especially with regards to modern fuels.

Our carbon and graphite products have exhibited exceptional process reliability in applications for water and fuel pumps. Our quality certifications (such as ISO TS16949) have documented this for years. Another beneficial factor is the pressed to size technology (PTS), which is of considerable advantage to our customers in terms of time and costs. We are able to press parts with an outer diameter of max. 80 mm (3.15" ) nearly 100 % to match their final form, which minimizes – or completely eliminates – follow-up machining work. Near-net-shape pressing pays off with production runs starting at just 2500.

c Bearings made of carbon graphite

Specialty graphites for fueland water pumps

Material suitability for specific applications

Applications ProductsSIGRAFINE

EK23 1) EK25 1) EK33 1) EK79

Fuel pumpsBearings ○ ○

Seal rings ○ ○ ○Commutator discs ○ ○

Water pumpsBearings ○ ○

Seal rings ○ ○

1) Information refers to the base material only. Different impregnations are available.

9

Gaskets and seals are a major factor when it comes to safety, good driving performance and low emissions values. We have been known as a dependable partner in this field for many years.

Our customers value our products’ excellent low-friction properties and outstanding resistance to wear and extreme temperatures.In particular, our SIGRAFLEX APX2 expanded graphite foil is the first choice in high-temperature applications. No other industrial graphite foil on the market exhibits a comparable level of oxidation resistance.

SpeCIALTy GrAphITeS For The AuToMoTIVe InDuSTry

c Cooling water pump with carbon seal ring and mechanical seal

c SIGRAFLEX foil

Specialty graphites for gaskets

Material suitability for specific applications

Applications ProductsSIGRAFINE SIGRAFLEX

EK23 1) EK33 1) EG31 EG32 V1032 KG19 A APX2Mechanical seals Seal rings ○ ○Turbocharger gaskets Seal rings ○Head gaskets Graphite foils ○Diesel particulate filters Graphite foils ○Plastic compounds Powder ○ ○ ○ ○

1) Information refers to the base material only. Versions with different impregnations are available.

10

Due to their specific design, modern diesel and gasoline engines do not generate sufficient vacuum for brake assist and other technical systems. This is why they are equipped with an additional electric vacuum pump for brake assistance. Electric vacuum pumps are part of the standard equipment for hybrid and electric vehicles as well.

We support our customers with our first-class products and cutting-edge material know-how.Our vanes and rotors made of specialty graphites or synthetic resin-bonded materials feature high strength and very good sliding properties. This is another case in which our customers benefit from pressed to size (PTS) technology due to the minimal amount of required machining.

c Rotor and vanes for brake assist pumpsc Vacuum pumps comfort seat function

Specialty graphites for vacuum pumps

Application-specific products for vacuum pumps

Applications ProductsSIGRAFINE

EK23 EK25 EK64 V1626

Brake assist pumpsRotors ○ ○Vanes ○ ○

Pumps for comfort applicationsRotors ○ ○Vanes ○ ○

11

Material development partner for EGR valve bearingsThe high temperatures in exhaust gas recirculation systems demand high-grade oxidation materials. This led us to develop a specialty graphite for bearings in EGR valves: SIGRAFINE V2064.

This material’s strength lies in its long- term stability at temperatures of up to 600 °C (1112 °F). We use PTS technology to provide our customers with near-net-shape parts, thus minimizing the need for follow-up machining work – a significant advantage in terms of time and costs.

This is just one example of an application-specific optimized solution from the SGL Group.

12

Fine-grain graphites for automotive applicationsQ Excellent dry-running properties in

tribological systems, resulting in high energy efficiency

Q Resistant to oxidizing atmospheres up to 500 °C (932 °F) with oxidation inhibitors up to 600 °C (1112 °F)

Q High corrosion-resistance

Q High mechanical material strength

We use our extensive experience of materials and applications to support our customers with individual consultation and supply them with products in high quality – even in large lot sizes.

13

Refined by a variety of impregnations Metal, phosphate and synthetic resin impregnations can be used to influence material’s properties and systematically optimize them for specific applications, such as increasing resistance to oxidation, wear or thermal conductivity.ʈ Metals and metal alloys such as bronze or antimonyʈ Synthetic resins ʈ Salts and saline solutionsʈ Hydrocarbons such as oils, paraffins, waxes or greases

Another option is the wide range of all-carbon gradesin our portfolio made of synthetic resin-impregnated,carbonized carbon which boast the following advantages:ʈ High strength and hardnessʈ Useable in oxidizing atmospheresʈ High resistance to chemical media

b Semi-finished product die-molded carbon and graphite

Excellent media resistance, low-wear, long-term stability.

Outstanding mechanical and chemical properties make fine-grain graphite the first choice for many applications in the automotive industry.

Material data for our various forms of SIGRAFINE® fine-grain graphite

Typical properties Units Die-molded carbon and graphite Isostatic

graphiteEK23 EK25 EK33 EK64 V2142 V2064 V1626

Density g/cm3 1.75 1.69 1.6 1.72 1.85 1.83 1.85Hardness Rockwell B 105 100 110 90 103 56 90Flexural strength MPa 40 45 73 70 80 54 58Young's modulus GPa 14 16 16 16 15 16 13

Thermal expansion 20 – 200 °C (68 – 392 °F) 10-⁶K-1 5 4.5 5.1 4 4.7 6.3 4.0

Thermal resistance in oxidizing atmosphere °C (°F) 350 (662) 350 (662) 350 (662) 220 (428) 550 (1022) 600 (1112) 600 (1112)

FIne-GrAIn GrAphITe

Materials made of SIGRAFINE® fine-grain graphite.

14

The various different SIGRAFINE materials have very good properties when it comes to wear. There are many different factors which generally influence wear behavior, such as the following:

ʈ Combination of materialsʈ Sliding speedʈ Stressʈ Surface finish of the contact surfacesʈ Solid impurities in the medium to be sealedʈ Operating conditions This means that we have to search the entire system in order to find the best material solution.

We provide professional technical and individual advice based on long standing experience.

tx Wear behavior of machined plain bearings of various SIGRAFINE grades of carbon at a constant sliding speed of 1 m/s(3.3 ft/s) and with increasing specific load in wet and dry running.

EK2240 = EK24 synthetic resin-impregnatedEK3245 = EK24 antimony-impregnated EK2200 = EK20 synthetic resin-impregnated EK3205 = EK20 antimony-impregnated

Wea

r [µm

/h]

Wea

r [µm

/h]

Specific load [N/mm2]

10

1

0.01

0.1

Silic

on c

arbi

deTu

ngst

en c

arbi

de

EK220010

1

0.01

0.1

0 2 4 6 8 10 12

0 2 4 6 8 10 12

Wear behavior depending on counterfaces

EK3205

EK3205EK2200

Wea

r [µm

/h]

Load [N/mm2], bearing ø 30/20 x 20 mm (ø 1.18/0.79 x 0.79 in)

1

0.1

0.0154321

Wear behavior wet running

EK20EK24

EK2240

EK3245

EK2200EK3205

Wea

r [µm

/h]

Load [N/mm2], bearing Ø 30/20 x 20 mm (Ø 1.18/0.79 x 0.79 in)

10

1

0.10 2.52 3.531.51.00.5

Wear behavior dry running

EK200

EK24EK305EK2240EK3245

s Wear behavior’s dependence on sliding speed against materials such as EK2200 and EK3205 at a constant sliding speed of 9 m/s (29.5 ft/s) and increasing stress. Medium: demineralized water.

Characteristic properties

15

c PTS seal rings made of die-molded carbon

tx The coefficients of friction were determined in a pin-on-disc test at 11 m/s (36.1 ft/s), a relative relative air humidity between 36 % and 43 % and a heated disc.

FIne-GrAIn GrAphITe

Silicon carbide disc (Ra ≈ 0.2)

0.7

0.6

0.8

0.9

0.5

0.4

0.3

0.2

0.1

60 80 100 120

EK20

EK3205

EK24

EK3245

0

Disc temperature [°C]

0Coe

ffici

ent o

f fric

tion

[µ]

Gray cast iron 20 disc (Ra ≈ 0.3)

EK2200

EK3205

EK24EK2240

EK3245

EK20

60 80 100 1200

Disc temperature [°C]

Coe

ffici

ent o

f fric

tion

[µ]

0.7

0.6

0.8

0.9

0.5

0.4

0.3

0.2

0.1

0

0

400

300

200

100

Ther

m. c

ondu

ctiv

ity [W

m-1K-1

]

Thermal conductivity of various materials

Cop

per

Gra

phite

Silic

on c

arbi

de

Plat

inum

Alu

min

um o

xide

Car

bon

grap

hite

Ther

mop

last

Ther

mos

et

Materials made of SIGRAFINE show impressive thermal conductivity.In fact, SIGRAFINE fine-grain graphite is many times more heat conductive than its surrounding components and prevents the system from overheating or components from being changed by increased wear.

16

Materials made of SIGRAFINE make a major contributionto process reliability thanks to their great resistanceto temperature and thermal shock.

What’s more, the coefficient of thermal expansion can be systematically controlled during material production in order to optimally modify SIGRAFINE components to match the counterface material. We help our customers accomplish this with extensive experience in materials.

Thermo-plast

Aluminum alloys

Stainless steel

Thermo-set

Chromium cast

Aluminum oxide

Tungsten carbide

Silicon carbide

Graphite

Coefficient of thermal expansion of various materials

30

40

50

20

0

10

Ther

mal

exp

ansi

on [1

0⁶K

¹]

Graphite Carbongraphite

Boron carbide

Silicon carbide

Aluminum oxide

Aluminum Steel Thermo-set

Thermo-plast

Thermal shock resistance of various materials

60

80

100

40

0

20

Ther

mal

sho

ck re

sist

ance

[%]

c PTS bearings

Graphite features the highest thermal shock resistance of all materials in existence. The most significant change in thermal shock resistance can be achieved by changing the material’s thermal conductivity. Thermal shock resistance is defined as:

δ = Strength x thermal conductivity

Coeff. of thermal expansion x Young's modulus

Combining materials with the same or similar thermal expansion coefficient provides good physical compatibility. The coefficient of thermal expansion can be adjusted by selecting the ingredients in the recipe.

17

Our special SIGRAFINE materials are well suited for wet and dry running as well as mixed friction.

We provide our customers with applicationspecific advice to find perfectly matching counterface materials to increase system performance.

In dry running conditions, the surface finish should generally be of a higher standard than when a liquid film is present. In the latter case, even hydrodynami-cally poor media such as water or gasoline will achieve some compensating effect and reduce friction.

Hard substances make good counterface materials for SIGRAFINE. Examples include:ʈ Gray cast ironʈ Steel – alloy, non-alloy and nitrided (hard)ʈ Hard metalʈ Aluminum oxideʈ Silicon carbideʈ Glassʈ DLC 1⁾ coated materials

The following materials are suitable under certain conditions:ʈ Steel – alloy and non-alloy (soft)ʈ Light metal alloysʈ Chromium-plated materialsʈ Nonferrous metalsʈ Carbon materials

c Various bearings made of die-molded carbon

Surface finish of metallic counterfaces

Stress v < 0.5 m/s v < 1 m/s v < 3 m/s p < 0.1 N/mm3 p < 0.2 N/mm3 p < 0.3 N/mm3

Rz μm ≈1 0.5 … 0.8 < 0.5

1) “Diamond-like carbon,” amorphous carbon resembling a diamond

FIne-GrAIn GrAphITe

Suitable counterface materials made of SIGRAFINE®

l

d₁ d₂d₁

b

r

15°15°

f x 45°

f f

f x 45°

d₂ d₃d₁ d₂

l

l

18

We recommend observing the following guidelines for design and calculation, depending on the specific application. Our calculation and design recommenda- tions are based on many years of project and application experience.We use this experience to help auto- motive companies get the best results when using our specialty graphites.

Design recommendations

Cylindrical and flanged bearings – design guidelines and calculation

Dry running and mixed running

Bearing dimensionsv (m/s) ≤ 1 projected bearing area I x d1 ≥

F l ≤ 2 d1

0.3 (N/mm2)

v (m/s) ≤ 0.1 projected bearing area I x d1 ≥ F l ≤ 2 d1

1.5 (N/mm2)

Bearing clearance0.3 ... 0.5 % of shaft diameter at operating temperature (warm clearance)

0.3 ... 0.5 % of shaft diameter at operating temperature (cold clearance)if shrunk into a metal housing

Coefficient of friction0.10 … 0.15 for mixed running0.15 … 0.25 for dry running

Wet running

Bearing dimensions1)

v (m/s) ≤ 20 projected bearing area I x d1 ≥ F l ≤ 2 d1

0.3 (N/mm2)

v (m/s) ≤ 15 projected bearing area I x d1 ≥ F l ≤ 2 d1

0.5 (N/mm2)

Bearing clearance1)

0.1 ... 0.3 % of shaft diameter at operating temperature (warm clearance)

0.1 ... 0.3 % of shaft diameter at operating temperature (cold clearance)if shrunk into a metal housing

Coefficient of friction 0.01 ... 0.05

1) Observe the laws of hydrodynamics.

Information for wet and dry running

TolerancesOutside diameter IT 6 / IT 7 Bore IT 7 / IT 8

Surface finishOutside diameter Ra = 6.3 μm … 3.2 μmBore Ra = 3.2 μm … 0.8 μm

Bearing design Do not subject bearing to tension, shear or bending stressFitting Cold fitting, shrink fitting, bondingCounterface materials (surface finish) Generally hard materials, e. g. HRC > 50, Rz = 0.5 … 0.8 μm

l

d₁ d₂d₁

b

r

15°15°

f x 45°

f f

f x 45°

d₂ d₃d₁ d₂

l

l

19DeSIGn reCoMMenDATIonS

Axial bearingsThe following information also applies to calculatingthe face surfaces of cylindrical and flanged bearingswhen loaded axially.

c Axial bearings in various designs

d1 = bearing bore (mm)d2 = bearing outside diameter (mm)d3 = flange diameter (mm)s = bearing wall thickness (mm)l = bearing length, respectively height (mm)F = radial or axial load (N)p = spec. Radial or axial load (N/mm2)b = flange thickness (mm)v = sliding speed (m/s)f = chamfer (mm)

Axial bearings – calculation guidelines and supplementary information

Dry Running / Mixed Running Wet Running

Bearing area A (mm2)

v (m/s) ≤ 1

A ≥ F0.3 (N/mm2)

v (m/s) ≤ 20

A ≥ F1.0 (N/mm2)

Coefficient of friction 0.1 ... 0.25 0.01 ... 0.05Surface finish Bearing surfaces fine-ground to lapped Bearing surface lappedBearing design Solid or split Solid or split, lubricating grooves

Fitting Cold press fitting, shrink fitting,screws, nuts and form closure

Cold press fitting, shrink fitting,screws, nuts and form closure

Counterface materials(surface finish)

Generally hard materials, e. g.z. B. HRC > 50

Rz = 0.5 ... 0.8 μm

Generally hard materials, e. g.z. B. HRC > 50

Rz = 0.5 ... 0.8 μm

Fitting

Method of fittingRecommended ISO tolerances Max. Operating Temperature °Cd₁ d₂ Housing diameter

Cold press fitting before F7after H7 ... H8 s6 H7 about 150 1)

Shrink fitting before D8after E8 ... E9 2) x8 … z8 H7 about 300 3)

1) For housing materials having a thermal expansion of α > 12 x 10−6/K the maximum operating temperature is correspondingly reduced. Press fitting is conducted with a stepped fitting pin with a tolerance of h5.²) We recommend that the bearing bore be finished to size after shrink fitting.³) For higher temperatures and for housing materials having a thermal expansion of α > 12 x 10−6/K the special tolerances and/or a locking arrangement may be employed – please inquire about this.

20

The following examples illustrate the aforementioned calculation and design guidelines.

b Cylindrical bearing made of die-molded carbon

Example: Cylindrical bearing calculation

Dry running

Given valuesSliding speed v = 0.5 m/sLoad F = 150 NTemperature 60 °C

Bearing dimensions

Projected bearing area l x d1 > = = 500 mm2

Bearing bore d1 >

chosen as d1 = ld1 = = 22.36 mm

rounded up d1 = 23 mm

Bearing length I = = 21.7 mm

rounded up l = 22 mm

Bearing outside ød2 = d1 + 2ssmin = 0.15 x d1 = 3.45 mm23 + 2 x 3.45 = 29.9 mm

rounded up d2 = 30 mmBearing dimensions ø 30/23 x 22 mmBearing playDry running 0.3 ... 0.5 % vom Wellen-ø dShaft ø 20 mm d = 23 h6

Bearing clearance (min.) 0.3 % x 23 = 0.069 mm(added to nominal bore)

Bearing tolerancesBearing outside ø chosen s6 (cold press fitting)Bearing bore chosen F7This results in: Ø 30 s6 / 23.069 F7 x 22 mm

Example: Axial bearing calculation

Wet running

Given values

Shaft ø 20 mmSliding speed v = 3 m/sLoad F = 500 NMedium Water Temperature 30 °C

Bearing dimensionsBearing bore d1 = 20 mm (given)

Bearing outside ø d2

By going back and calculatingfrom the required area A = = = 500 mm2

this results in

A = d2 =

d2 =

d2 = 32 mm

Bearing outside øchosen as d2 = 35 mm

Bearing height l > 0.1 d3

chosen as l = 5 mm

π (d2² – d1²)4

500 x 4π

+ 20²

A x 4π

+ d1²

l

b

l

d₂

s

s

d₁

l

b

l

d₂

s

s

d₁

l

b

l

d₂

s

s

d₁

l

b

l

d₂

s

s

d₁

l

b

l

d₂

s

s

d₁

l

b

l

d₂

s

s

d₁

21

Over the years, our design recommendations have proven themselves time and again and help attain the greatest possible process reliability – by minimizing the risk that the bearings will break, for instance.

b Various bearings made of die-molded carbon

DeSIGn reCoMMenDATIonS

Any arrangement such as a check plate or plainpin to prevent rotation should be provided inan unloaded area, not in the bore. Any keywayshould be axial and milled out carefully to avoidbreakage.

Bearing Design

Bearings for dry running should have a smooth bore. If bearings are running wet, bores should have spiral grooves or axial grooves according to the application.

Height I ≥ 0,1 d2;Not under 3 mm (0.12"), if possible

Avoid sharp steps in the bore and on the outside. Break sharp edges!

Cylindrical bearings should not be fitted to be self-supporting. They should be fully supported by the housing or by a special metal bushing.

Cylinder thicknessI ≤ 2d1; s = 0,15 ... 0,2 x d1;smin = 3 mm (0.12")

Flange thickness should be at least equal to wall thickness; A transitional angle should be radiused; machine the housing thrust face for the flange. b ≥ s

22

SIGRAFLEX® for static engine sealing applicationsSIGRAFLEX flexible graphite grades are specifically designed for sealing applications in automotive and diesel engine and exhaust areas.

One of the key strengths of our product line is in temperature resistance.

Our wide range of products allows design engineers to chose the best product for their application design needs.

23FLeXIBLe GrAphITe

Comparision of SIGRAFLEX APX2 to Mica

1 h / 100 °C (212 °F) 5 h / 500 °C (932 °F)100

10

1

0,1

0,01

0,001SIGRAFLEX APX2 Mica

x 1800

x 16n

Loss

of l

eak-

tight

ness

of n

itrog

en [m

l/min

]

Government regulations are increasingly requiring automotive and diesel manufacturers to reduce vehicle CO2, NOx and diesel particulate emissions in higher and higher temperatures. This is where sealing materials used in these applications play a critical role.

Our flexible expanded graphite sealing materials have been used in the most demanding engine sealing applications for decades.

SIGRAFLEX flexible graphite grades are used in sealing applications which demand great durability, reliability and safety and impermeability and call for resistance to extreme temperatures and enhanced sealing characteristics.SIGRAFLEX flexible graphite is resistant to most chemicals and sets itself apart from other sealing materials with its long-term sealing characteristics up to temperatures of more than 500 °C (932 °F).

SIGRAFLEX® foils made of flexible graphite.Sealing demanding engine applications – even under the toughest conditions.

Material data for SIGRAFLEX® flexible graphite

Typical properties UnitsSIGRAFLEX

APX2 APX AP AThickness mm (in) 0.2 - 1.52 (0.008 - 0.06) 0.35 - 2.0 (0.01 - 0.08) 0.25 - 1.52 (0.01 - 0.06) 0.25 - 2.0 (0.01 - 0.08) Width m (in) 1.0/1.5 (40/60) 0.5/1.0/1.5 (19.7/39.4/59.1) 1.0/1.5 (40/60) 1.0/1.5 (40/60)Purity % ≥ 98 ≥ 98 ≥ 95 ≥ 95Ash content % ≤ 2 ≤ 2 ≤ 5 ≤ 5Density (graphite) g/m3 (lb/ft3) 1.12 (70) 0.7 - 1.3 (44 - 81) 1.0 - 1.12 (62.4 - 70) 1.0 - 1.44 (62.4 - 90)Sulfur content ppm < 300 < 500 < 1000 < 1500Chloride content ppm ≤ 25 ≤ 25 ≤ 50 ≤ 50

24

Weight loss of SIGRAFLEX

100

10

1

0.1

0.01

0.0001

0.001

400/752 500/932 600/1112 700/1292

Wei

ght l

oss

[%/h

]

Temperature [°C/°F]

AP

A

APX2

c SIGRAFLEX APX2 products for a wide range of automotive applications

Our SIGRAFLEX APX2 flexible graphite was developed for the rigorous demands of automotive and diesel exhaust systems. It is currently being used in a wide range of sealing applications including exhaust gasket rings, exhaust gas recirculation (EGR) gaskets, exhaust manifolds, exhaust pipe gaskets, and diesel particulate traps.

Thanks to its enhanced properties, SIGRAFLEX APX2 flexible graphite is used to meet the increasing temperatures and strict environmental requirements on exhaust systems. It has very little weight loss due to oxidations, even under high temperatures. Our proprietary oxidation inhibitor and production process allows the inhibitor to be incorporated into the structure of the graphite foil, fully optimizing the oxidation resistance behavior.

25

Lifetime expectations and influence of design and assembly

The lifetime of flexible graphite foil gaskets depends highly on gasket design, medium and assembly. The density of graphite in the application ranges from 1.6 to 2.0 g/cm³. The weight loss expectation needs to be considered accordingly. The exposure of graphite also depends on the gasket design. Flat gaskets (like exhaust manifold and EGR gaskets) have approximately 5 % exposed material faced to the oxidizing medium. Exhaust ring gaskets are almost fully covered and are only 1-2 % exposed. The thermal stability of SIGRAFLEX APX2 flexible graphite is superior to that of all other standard and inhibited felxible graphite grades in the markeplace today. This can be observed in the graphs below, which show weight loss as a function of temperature.

FLeXIBLe GrAphITe

Headline

Wei

ght l

oss

[%]

100

80

60

40

0

20

0 20 40 60 80 100

Air exposure [%]

Headline

1 1.2 1.4 1.6 1.8 2

Wei

ght l

oss

[%]

Compressed density [g/cm³]

100

80

60

40

0

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dh These images illustrate the general properties of SIGRAFLEX in terms of weight loss at temperatures of 500 - 650 °C (932 - 1202 °F)

c SIGRAFLEX APX2 tang reinforced ring gasket (left) and standard flexible graphite tang reinforced ring gasket (right) after exposure to 600 °C (1112 °F) for 4 hours

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We will find the best solution – in partnership with you.The fascinating potential of carbon as a material excites us and inspires us to develop optimum solutions in partnership with our customers.

With our comprehensive material portfolio and valuable specialist know-how, we can manufacture tailored products – even for the most challenging applications.

Consistently high quality, a global presence, innovative strength, and the extensive experience of our employees make us a reliable partner to our customers.

Whatever challenges you face, together we will find the best solution.

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b Lathe turning work on rotors

SGL Group – The Carbon Company.A leading global manufacturer of carbon-based products.Q Unique product portfolioQ Innovative technologies and solutionsQ Production sites close to sales marketsQ Technology & Innovation Center in Germany with international networks

We have wide-ranging expertise in raw materials, advanced manufacturing processes, and long-standing application and engineering know-how.We have a comprehensive portfolio of carbon, graphite, and carbon fiber products and our integrated value chain covers everything from carbon fiber to composites. With a global sales and distribution network and modern production sites in Europe, North America, and Asia, we are close to our customers throughout the world.

We use this broad base to offer our customers the best solutions possible. That’s how we live up to our claim: Broad Base. Best Solutions. This claim is also upheld by our corporate SGL Excellence philosophy of continuous improvement.

More information can be found by visiting: www.sglgroup.com C sglgroup sglgroup

SGL Group – The CArBon CoMpAny

Graphite Materials & SystemsSGL CARBON GmbH Soehnleinstrasse 8 | 65201 Wiesbaden/Germanywww.sglgroup.com/gms

europe/MIDDLe eAST/AFrICASGL CARBON GmbHDrachenburgstrasse 153170 Bonn/Germanymechanical-europe@sglgroup.com

ASIA/pACIFICSGL CARBON Japan Ltd.13-5 Midoridaira, Sosa-shi289-2131 Chiba/Japanmechanical-asia@sglgroup.com

AMerICASSGL TECHNIC Inc.Polycarbon Division28176 No. Avenue StanfordCA 91855 Valencia/USAmechanical-americas@sglgroup.com

® registered trademarks of SGL CARBON SE 05 2015/0 1NÄ Printed in GermanyThis 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 prod-ucts described or their suitability for a particular application. Any existing industrial property rights must be observed. The quality of our products is guaranteed under our “General Conditions of Sale”.

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