Unrivalled
Sealing
Our specialty graphites
for sealing technology
SIGRAFLEX®

Graphite Solutions

250
SIGRAFLEX® HOCHDRUCK
Leak tight –even under high pressure
The SIGRAFLEX HOCHDRUCK gasket is rated to 250 bar¹⁾. It thereby meetshigh demands for sealability, making gaskets extremely safe and reliable.
Our unique technology makes this possible, creating a high-strength,
adhesive-free laminate. The gasket is also available in a PRO version(TA Luft compliant) or made with SIGRAFLEX APX2® foil for high-temperatureprocesses. Intelligent solutions from SGL Carbon – unrivalled sealing.

¹⁾ 250 bar = 3625 psi

bar

4

Our specialty graphites
for sealing technology
Enjoy the benefits of our outstanding material
properties and of our quality products for awide range of sealing applications.

Your benefits
Greater process reliability, significantly longer service life ofequipment, minimization of emissions and downtimes with theensuing lower operating costs.

Typical applications

Take advantage of our expertise in application technology.
We would be pleased to support you in optimizing your processes and developing specific solutions to meet your needs.
TA Luft (Technical Guidelines on Air Quality Control)
We also provide support in complying with the latest clean air
regulations and emission regulations such as TA Luft.

Products of SGL Carbon

Materials used by SGL Carbon

Unrivalled sealing | Overview

Flanges, joints, connectors

Rotating equipment

Static equipment• EN / ANSI flanges• Flanges and joints• Pipelines• Mixers and vessels• Heat exchangers• Flat gaskets• Non-metallic flat gaskets• Kammprofile, corrugated andspiral wound gaskets• Process pumps• Stuffing boxes• Braided packings• Flat gaskets• Packing rings (die-forming rings)• Valves• Fittings• Valve/pump bodies• Stuffing boxes• Flat gaskets• Braided packings• Packing rings (die-forming rings)• Graphite foils• Unreinforced and reinforcedgraphite laminated sheets• Graphite foils• Textile carbon and graphite
packing yarns• Foil yarns• Unreinforced and reinforcedgraphite laminated sheets• Textile carbon and graphite
packing yarns• Foil yarns• Graphite foils• Unreinforced and reinforcedgraphite laminated sheets• SIGRAFLEX® flexible graphite• SIGRAFLEX® flexible graphite• SIGRAFLEX® yarns• SIGRAFLEX® flexible graphite• SIGRAFLEX® yarns

Other solutions, products and materials from SGL Carbon for related fields:• Solutions for highly corrosive applications: Systems, HCl syntheses, plate heat, block heat andshell and tube heat exchangers, columns, column internals, vessels, reactors, quenchers,
pumps, bellows, piping, rupture disks made of the materials DIABON®, POLYFLURON®, SICABON®
and SIGRABOND®.
• Specialty graphites for mechanical engineering: for axial face seals, seal rings and bearings of
SIGRAFINE® die-molded and isostatic carbons and graphites.
More information: www.sglcarbon.com

5

6

SIGRAFLEX®

The solutions described in our SIGRAFLEX
portfolio are as wide ranging as ourcustomers’ demands on sealing materials.

SIGRAFLEX ECONOMY sheet, graphite rayon yarn and Z foil

Unrivalled sealing | Portfolio

Safety provided by quality
SIGRAFLEX flexible graphite and yarn products are characterized by their high standard of quality. The proven quality of ourmaterials considerably enhances process reliability.
Resistance and long-term stability
Products made of SIGRAFLEX are chemically resistant against
the vast majority of media, and largely against radiation too.
Furthermore, our graphite foils and sheets boast sealing properties with long-term stability of temperatures up to approx.
550 °C (1022 °F) which, depending on type of installation, is far
above other materials. These aspects are also advantageouswhen sealing highly volatile gases such as hydrogen, even atvery low temperatures of e.g. -253 °C (-423 °F).
Compliance with legal requirements
The high material quality assures that gaskets made fromSIGRAFLEX products easily comply with legally establishedvalues for emissions. We also provide many products
which meet the stringent demands of such regulations as
the Technical Instructions on Air Quality Control (TA Luft)(see table page 17).
Reduced maintenance costs
The long service life of our material leads to a significant
reduction in maintenance costs, thereby increasing thecost effectiveness of equipment.

7

Quality features
When manufacturing SIGRAFLEX foil, we use only
high quality natural graphite, which is expanded ina thermal process and is without binders or fillers.
The result:

Outstanding sealing properties• Low permeability to gases and liquids• No cold or warm flow up to maximum permissible
gasket pressure• Smooth temperature change behavior

Stability• High resistance to chemical media and radiation• Absence of binders means no ageing or embrittlement• High residual stress• Long-term stability of compressibility and recovery
over a wide temperature range

Range of use from – 269 °C (– 452 °F)
to approx. 3000 °C (5432 °F)• Depending on installation and operating conditions• To approx. 800 °C (1472 °F) in an inert atmosphere(limits imposed by metal reinforcement to beobserved)• In air to approx. 400 °C (752 °F) to 600 °C (1112 °F)*

Anisotropic properties• Properties highly anisotropic particulariy in respectof electrical and thermal conductivity

User benefits• Flexibility, softness• No health risks and environmentally friendly

You will find certificates, licenses and test reports forour products in the Download Center of our website:www.sigraflex.com/downloads* We are pleased to make specific recommendations.

8

Processing of SIGRAFLEX®
foils, sheets, and yarns
Using various methods, our SIGRAFLEX semi-finished products
can be processed into a wide range of seals and other products.

Semi-finished product

Processing techniqueEnd product

Foil tapes
Winding and pressing

Packing rings

Corrugating

Corrugated tapeWindingSpiral wound graphite gaskets

Punching

Gaskets

Punching and bonding

Graphite outer layers for
Kammprofile gaskets

Cutting and punching

Electrodes
Heating elements
Linings

Punching

Self-adhesive gaskets

Cutting and corrugating

Sealing tapes,
self-adhesive

Braiding

Braided packing

Cutting / cutting-off
SIGRAFLEX foils

Coating
SIGRAFLEX self-adhesive
foil with release paper(example, other coatings
also available)

Packing yarns

Unrivalled sealing | Portfolio

Material type
Unreinforced sheets
SIGRAFLEX BASISSIGRAFLEX STANDARD
SIGRAFLEX B

Processing techniqueEnd productSimple gaskets

Punching

Smooth stainless steel ringgaskets with graphite outerlayersCutting
Scarf cutting

Corrugated stainless-steel ringgaskets with graphite outerlayersBonding

Reinforced sheets
SIGRAFLEX iNXTSIGRAFLEX ECONOMYSIGRAFLEX BSSC
SIGRAFLEX with otherreinforcements(e.g. nickel, Hastelloy,
wire mesh, polyester foil)

SIGRAFLEX UNIVERSALSIGRAFLEX UNIVERSAL PRO
SIGRAFLEX BTCSSSIGRASEAL

iNXT: Pipework gaskets for
TA Luft applications

Punching
Cutting
Scarf cutting

Gaskets forpumps and fittings

Punching

Pipework gaskets

Cutting

UNIVERSAL PRO:for TA Luft applications

Scarf cutting

SIGRAFLEX HOCHDRUCKSIGRAFLEX HOCHDRUCK PRO
SIGRAFLEX APX2 HOCHDRUCK

High-quality gaskets
e.g. with metal eyelets forvarious applications
Punching
HOCHDRUCK PRO:for TA Luft applications

Cutting
Scarf cutting
Typical seal cross-sections

APX2 HOCHDRUCK:
for high-temperatureapplications

SIGRAFLEX MF®
Punching
Cutting

Superior-quality gaskets
with s/s inner eyelets for
maximum safety, outstandinganti-stick behavior in flange,and sealability

9

10

SIGRAFLEX
graphite foils®

We manufacture a broad range of SIGRAFLEX foil types fordifferent applications. They feature high reliability,
even under extreme operating conditions.

SIGRAFLEX foil

Unrivalled sealing | Graphite foils

Increasing challenges
Industrial manufacturing processes are becoming more andmore complex, and more demanding on the materials used.
In particular higher process temperatures, reductions inequipment downtimes, and increased product quality demand
optimum material solutions. SIGRAFLEX foils made of expanded
natural graphite support endusers around the world in producing
high quality products for safe processes.

11

Largest variety in the market
With our support, select exactly the product which mostclosely meets your requirements from the largest portfolioof flexible graphite foils in the world: For example oxidation
resistant, high-purity or industrial quality foils, and grades thatexhibit low friction characteristics etc.
Long-term stable mechanical behavior
All of our foils are distinguished by their long-term stability.
This is a crucial benefit and stands in contrast to othermaterials exhibiting high flow characteristics which is
detrimental to the long-term integrity of a joint seal. Even
when surface stress reduces during operation, the sealing
effect of SIGRAFLEX is largely maintained.

Custom-designed features of our SIGRAFLEX® graphite foils
Foil type
Application

Chemical and petrochemical
Spiral wound gaskets
Kammprofile
Corrugated gaskets
Packing rings
Power generation
Spiral wound gaskets
Kammprofile
Corrugated gaskets
Packing rings
Refining
Spiral wound gaskets
Kammprofile
Corrugated gaskets
Packing rings
Automotive
Gaskets in exhaust system
Cylinder head gaskets

APX2

BP

AP

APX

E

SHL

C

B

A

N

Z

ZX

AQ

TF

S

12

SIGRAFLEX®
graphite foils withoxidation resistance
SIGRAFLEX foils made of expanded natural graphite are
distinguished by their high-temperature resistance. They
are the first choice in sealing applications for long-term
use at high-temperatures.

↑ Die-formed packing ring made of SIGRAFLEX tapes for use in stuffing boxes.

Extremely low weight loss
Compared to other industrial graphite foils, our types
SIGRAFLEX APX2, BP, AP, APX and E exhibit remarkable
oxidation resistance. Their typical weight loss (in TGA testin air at 670 °C (1238 °F) for four hours) is at 2% per hour andless, while conventional industry foils lose up to 40%.
The lower the weight loss, the better and more extensiveis the performance of the material – making our SIGRAFLEXAPX2 foil, which, in the same test parameters, typically only
loses 0.6% of its weight per hour, the unrivalled “Best in Class”.
Fulfilling specifications
When it comes to corrosion protection, SGL Carbon offers thewidest-ranging portfolio on the market. With their low sulfur
and halogen content, our foils fulfill user specifications and are
genuine high performers in system protection.

Relative weight loss of SIGRAFLEX foils:
APX2 is “Best in Class”
Typical relative weight loss of SIGRAFLEX foils in air at 670 °C/1238 °F
Weight loss [% / h]
2.0 —
1.5 —
1.0 —
0.5 —

E

APX

AP

BP

APX2

Material data of our SIGRAFLEX® oxidation resistant graphite foils
Typical properties

Unit

APX2

BP

AP

APX

E

Thickness
PurityAsh content
DensitySulfur content
Chloride content

mm
in
%
%
g/cm³
ppm
ppm

0.25 – 1.52
0.01 – 0.06
≥ 98
≤2
1.0 – 1.12
< 300
≤ 25

0.25 – 3.05
0.01 – 0.12
≥ 98
≤2
0.7 – 1.43
< 300
≤ 50

0.25 – 2.0
0.01 – 0.08
≥ 98
≤2
1.0 – 1.12
< 300
≤ 50

0.35 – 1.0
0.014 – 0.04
≥ 98
≤2
0.7 – 1.3
< 300
≤ 25

0.35 – 1.0
0.014 – 0.04
≥ 99
≤1
0.7 – 1.3
< 300
≤ 10

%/h

≤1

≤2

≤2

≤3

<4

Weight loss in air
at 670 °C/1238 °F (TGA)¹¹ Values for material thickness ≥ 0.5 mm and density ≥ 1.0 g/cm³						Unrivalled sealing | Graphite foils

13

SIGRAFLEX®
industrial quality foils
Our SIGRAFLEX industrial quality foils boast outstanding
sealing properties.
Elastic, malleable, and reliable
SIGRAFLEX foil is compressible and easy to shape. It fits wellagainst the surface to be sealed, even on uneven surfaces, aclear advantage over other sealing materials.
↑ SIGRAFLEX foil can be cut into tapes.

Easy to process
In addition to its outstanding workability, SIGRAFLEX foils are
particularly easy to cut, to press and to punch, for example intapes, corrugated tapes and packing rings.

Material data of our SIGRAFLEX® graphite foils inindustrial quality
Typical properties

Unit

C

B

Thickness
PurityAsh content
DensitySulfur content
Chloride content

mm
in
%
%
g/cm³
ppm
ppm

0.35 – 3.0
0.014 – 0.12
≥ 98
≤2
0.7 – 1.3
< 300
≤ 25

0.25 – 3.0
0.01 – 0.12
≥ 98
≤2
0.7 – 1.4
< 500
≤ 50

↑ SIGRAFLEX foil tapes can be made into corrugated tapes.

↑ As a highly effective gasket material, SIGRAFLEX foil can also be pressed into
packing rings.

14

SIGRAFLEX® high-purity
graphite foils
High-purity natural graphite
SIGRAFLEX flexible foils are manufactured without the use ofadhesives and binders. We use high-purity natural graphite
flakes as our base material. This minimizes contamination
which significantly reduces the leakage rate, as well as thethermal and corrosion resistance of graphite gaskets on steel
flanges.

Protection from corrosion
Thanks to its very high-purity – for a part of the products ash
content of maximum 0.15 %, chloride and fluoride of maximum
10 ppm and sulfur content below 300 ppm – SIGRAFLEX foils makea significant contribution to protecting adjoining components
from corrosion.
This increases the operating reliability and the entire service
life of equipment. Our products contribute significantly to
cutting costs in static and dynamic sealing connections, piping,pumps, fittings, and vessels.
Our high-purity foils are especially suited to extreme requirements, such as sensitive processes in power plants.

↓ Kammprofile gaskets with soft facing material of SIGRAFLEX graphite foil.

Unrivalled sealing | Graphite foils

15

Material data of our high-purity SIGRAFLEX® graphite foils
Typical properties

Unit

N

Z

ZX

S

Thickness
PurityAsh content
DensitySulfur content
Chloride content

mm
in
%
%
g/cm³
ppm
ppm

0.25 – 1.52
0.01 – 0.06
≥ 99.5≤ 0.5
0.7 – 1.12
< 300
≤ 50

0.15 – 3.0
0.006 – 0.12
≥ 99.85≤ 0.15
0.7 – 1.3
< 300
≤ 10

0.37
0.015
approx. 98
approx. 2
0.95
< 300
≤ 20

0.25 – 1.52
0.01 – 0.06
> 99
<1
1.12
< 300
≤ 10

The thermal conductivity of SIGRAFLEX foils is strongly direction dependent (anisotropy) and can thus be regulated.
Thermal conductivity of SIGRAFLEX foils as a function of density (at room temperature),
left: parallel to surface, right: perpendicular to surface
Thermal conductivity [Wm –1 K –1 ]Thermal conductivity [Wm –1 K –1 ]

500 —

7—
6—

400 —

5—
300 —

4—

200 —

3—
2—

100 —

0.0

1—

0.2

Density [g/cm 3 ]

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

0.0

0.2

Density [g/cm 3 ]

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

16

SIGRAFLEX
graphite sheets®

The various types of SIGRAFLEX graphite sheets
provide an effective sealing solution for ourcustomer´s demands.

SIGRAFLEX UNIVERSAL PRO

Unrivalled sealing | Graphite sheets

The wealth of possibilities
Unreinforced or reinforced, with or without impregnation:
The portfolio of SIGRAFLEX graphite sheets provides a variety
of solutions to all needs.

We provide support with all TA Luft issues
If your equipment has to meet the requirements of the“Technical Instructions on Air Quality Control” (TA Luft),our wide variety of reinforced and impregnated SIGRAFLEX
graphite sheets provide the optimum sealing material.

Adhesive-free, high performing sheets for extreme sealing andsafety requirements, adhesive-bonded grades for standard
gasket stress and many specific variants – whichever thesituation, we have the SIGRAFLEX graphite sheet for yourindividual application.

Flange design

One-piece gaskets up to 1500 mm (59.1")
diameterFlanges with sealing strips
Flanges with tongue and groove design/sealed joints under high stress
Unstable flanges with low gasket stress
Vessel and equipment flanges

Operations underpressure

Operatingtemperatures
Leak tightness

Emergency repairs and complex
dimensions
Low internal pressure up to 40 bar
Internal pressures from vacuum
up to 100 bar
Internal pressures from vacuum
up to 250 bar− 269 °C to 300 °C (-452 °F to 572 °F)− 269 °C to ~ 550 °C (-452 °F to ~ 1022 °F)1)
Maximum requirements according to theemission protection regulation “Technical
Guidelines on Air Quality Control” (TA Luft)¹⁾ In consideration of chemical resistance. We will be glad to provide specific recommendations for operational temperatures of over 450 °C (842 °F).
Suitable

Recommended

C

SS
BTC

AL

Kammprofile and corrugated gaskets
PTFE envelope gaskets
Gaskets for pumps and valve bodies

BSS

A SE

IL
EM A

SIGR

RUC
C HD
MF

2 HO
A PX

PRO
HDR
HOC

UCK

HDR

EC T
S EL

HOC

UCK

PRO
T
iN X

SAL
V ER
UNI

Y

SAL
V ER
UNI

RD

NOM
EC O

ND A
S TA

Scope of applicationK

And that’s not all: we would be pleased to support you on site,
and together develop a sustainable solution tailored to yourneeds. Please just ask us.

Application-specific suitability of our
SIGRAFLEX® graphite sheets

Gaskets17

18

In the interest of your safety
Our reinforced SIGRAFLEX graphite sheets are highly corrosion
resistant. This considerably reduces the maintenance costsof equipment and extends its service life. Above all, the useof premium SIGRAFLEX materials significantly enhances sealsafety for employees and the environment – a high priority
when operating equipment.
Comprehensive knowledge of applications
Our broad portfolio of reinforced graphite sheets makes it
possible to find suitable materials for the specific requirementsof all types of equipment. It allows to select variants withespecially low halogen and sulfur content, as well as materials
with a compressibilty of 30 to 50 % to adapt to the irregularitiesof the sealing faces which in turn prevents crevice corrosion.
Our products have been developed with an in-depth understanding of how they will be used.
Let us advise you – together we will work out the best solution
for your specific requirements.
↑ SIGRAFLEX BTCSS and BSSC sheets. BSSC grade sheets are bonded sheets
reinforced with stainless steel. BTCSS is an adhesive-free sheet consisting of
two layers of graphite foil and a perforated-steel insert.

Over 10000 hours and beyond
stable leakage rate

Superior load capacity:
adhesive-free reinforced graphite sheets

Change in leakage rates of various sealing materials in long-term trials,
measured on a DN 40 PN 40 flange in accordance with DIN 28090-1 and -2

Max. permissible contact pressure for gaskets made of reinforced SIGRAFLEX
graphite sheets with a thickness of 2 mm (0.08'') at 300 °C/572 °F(acc. to DIN 28090-1)

Leakage rate [mgs-1m-1]

Permissible maximal contact pressure [N/mm2 ]

1.0 —

300 —

0.1 —
0.01 —
0.001 —

Flexible graphite (200 °C/392 °F)

200 —Elastomer-boundfiber gasket (200 °C/392 °F)

100 —Standard PTFE (150 °C/302 °F)

0.0001 —2
4
Width to thickness ratio
1

10

100

1000

10000

Test duration [h]Due to the warm flow characteristics of PTFE, the test temperature for thismaterial was set at only 150 °C (302 °F)

6

8

SIGRAFLEX HOCHDRUCK /HOCHDRUCK PRO
SIGRAFLEX UNIVERSAL /UNIVERSAL PRO
SIGRAFLEX MF
SIGRAFLEX SELECT
Graphite sealing with high adhesive/binder content

1012Unrivalled sealing | Graphite sheets

19

Material data of our SIGRAFLEX® reinforced adhesive- and binder-free graphite sheet

Typical properties

Unit

HOCHDRUCK PRO
2–9 inserts

APX2 HOCHDRUCK
1-5 insertsMF
3–7 inserts

Metal reinforcement:
Stainless steel sheet 316L

mm
in

0.05
0.002

0.05
0.002

0.05
0.002

Metal reinforcement:
Perforated stainless steel sheet
316L

mm
in

Thicknessmmin

1.0 – 4.0
0.04 – 0.16

Width

mm
in

LengthPurityAsh content
Chloride content

mm
in
%
%
ppm

UNIVERSAL PRO
1–2 inserts

SELECT¹
2 inserts

0.05
0.002

0.1
0.004

0.1
0.004

1.0 – 3.0
0.04 – 0.12

2.0 / 3.0
0.08 / 0.12

1.6 / 2.0 / 3.0
0.06 / 0.08 / 0.121000 / 1500
39.4 / 59.1

1500
59.1

1000
39.4

1000 / 1500
39.4 / 59.1

1000 / 1500
39.4 / 59.1
≥ 99.85≤ 0.15
≤ 10

1500
59.1
≥ 98
≤ 2.0
≤ 25

1000
39.4
≥ 99.85≤ 0.15≤ 101000 / 1500
39.4 / 59.1
≥ 98
≤ 2.0
≤ 25

≥ 98
≤ 2.0
≤ 25

BTCSS
1 insert

BSC
1 insert

1.6
0.06¹⁾ Sold in gasket form.

Material data of our SIGRAFLEX® reinforced bonded graphite sheets

Typical properties

Unit

iNXT
1 insert

ECONOMY ¹⁾
1–2 inserts

BSSC
1 insert

Metal reinforcement:
Stainless steel sheet 316L

mm
in

0.05
0.002

0.05
0.002

0.05
0.002

Metal reinforcement:
Perforated stainless steel sheet
316L

mm
in

Wire mesh reinforcement:
Stainless steel 316,
wire diameter
Bonded/adhesive-free

0.1
0.004

mm
in
adhesive-freebondedbondedadhesive-free

0.19
0.0075bondedThickness

mm
in

2.0
0.08

0.55 – 3.0
0.022 – 0.118

0.76 – 3.05
0.03 – 0.12

0.76 – 3.05
0.03 – 0.12

0.76 – 3.05
0.03 – 0.12

Width

mm
in

1000
39.4

1000
39.4

1000 / 1500
39.4 / 59.1

1000 / 1500
39.4 / 59.1

1000 / 1500
39.4 / 59.1

LengthPurityAsh content
Chloride content

mm
in
%
%
ppm

1000
39.4
≥ 98
≤2
≤ 50

1000
39.4
≥ 98
≤2
≤ 25

1000/ 1500
39.4 / 59.1
≥ 98
≤2
≤ 50

1000 / 1500
39.4 / 59.1
≥ 98
≤2
≤ 50

1000 / 1500
39.4 / 59.1
≥ 98
≤2
≤ 50

¹⁾ Also available in rolls up to 1 mm (0.04") thick.

20

Successful
together
We do not just manufacture products,
but also provide intelligent solutions
with sustainable benefits for ourcustomers.
Close collaboration and an understanding of specific requirements allow us
to develop forward-looking solutions
and respond to specific needs.
This has given rise to most of ourinnovation – such as the SIGRAFLEX
MF, APX2 HOCHDRUCK and iNXT
gasket sheets.

Unrivalled sealing | Successful together

21

Nothing sticks
Downtime is an extreme cost factor in the management of any piece of equipment, so incidental
maintenance needs to be kept to a minimum.
After years of use, flat gaskets often stick toflanges, so when it is the time to replace themit requires additional time and effort to do so.
There is also the risk of damaging the flange inthe removal process.
With ever increasing maintenance and downtime
costs, we offer material solutions with excellent
anti-stick properties for both standard and highend sealing applications saving the user valuable
time and money: Our impregnated SIGRAFLEX
graphite sheets have been used for years by manywell-known chemical companies because of theirsuperior antistick properties.
Our three component sheet offering the ultimate
in anti-stick properties is:

SIGRAFLEX® MF
SIGRAFLEX MF gaskets do not stick, whether atroom temperature or at 300 °C (572 °F).
The gasket is easily removed from the flanges
without leaving any residue, consequently there
is no need to clean the flange faces thus avoiding
damaging the flange during disassembly.
Users save time and money whenever a gasket
is replaced.

22

SIGRAFLEX
carbon and graphiteyarns®

Due to the variety of pre-cursor materials, carbon andcoating content, our SIGRAFLEX packings yarns provide
specific solutions for many different applications.

SIGRAFLEX carbon and graphite yarns

Unrivalled sealing | Carbon and graphite yarns

Broad spectrum for different requirements
We offer a wide variety of options in the manufacture of our
SIGRAFLEX packing yarns, and can optimally design final yarn
properties based on pre-cursor material, carbon content,
number of plies and filaments, twisting, coating, and weight.
This results in a comprehensive portfolio fulfilling needs anddemands of our customers.
Advantages of SIGRAFLEX yarns
Our customers benefit from the use of packings made of highquality and high-purity yarns from SGL Carbon. They offer aunique combination of tightness and heat dissipation, excellent high-temperature and chemical resistance, as well as
reduced contamination of processes due to the high purity of
the yarns.

23

High-performing graphite yarns for braided packing
We offer yarns made of different base materials, depending on
your requirements:• Rayon: Soft, compliant yarn that is stable at high temperatures.
• Graphite foil: Over knitted flexible graphite yarn suitable forhigh temperatures, oxidation and corrosive environments.
• PAN: Our graphitized PAN yarns stand out due to their excellent oxidation resistance. When specially coated, they also
meet the latest Shell specification MESC SPE 85/204.
We support you
The quality and state of the yarn used is crucial to the properties of braided packing. We are looking forward to helping you
select the ideal variant for your specific application. Pleasejust ask.

Application-specific suitability and product characteristics
of our SIGRAFLEX® carbon and graphite yarns
Pre-cursor material

Application

PAN
CarbonPAN
stretch broken
CarbonPAN
Graphite

PAN
stretch-broken
Graphite

Rayon
Graphite

Flexiblegraphite¹⁾

Carbon≥ 94

Carbon≥ 94

Graphite≥ 99

Graphite≥ 99

Graphite≥ 99.9Graphite≥ 98 - 99.85

< 400
< 752
2 – 12very highS, Z, ribbon

< 400
< 752
2 – 12
high
S, Z

< 500
< 932
0 – 14very high
S, Z

< 500
< 932
1 – 14
high
S, Z

< 450
< 842
1 – 14moderate
S, Z

< 580
< 10760 – 14low

Military applications
Power plants
Nuclear power plants
Refineries
Petrochemical installations
Chemical plants
Paper and cellulose industry
High-speed pumps
Steam applications
Valve packing
Piston-pump packing
Temperature > 2000 °C (non-ox)
Product characteristics

Type
Carbon content²⁾
Temperature³⁾
pH range⁴⁾
Tensile strength
Twisting

Unit

%
°C
°F

¹⁾ Data of wire-reinforced foil yarn unless otherwise indicated. ²⁾ Base yarn without coating /reinforcement.
³⁾ Approximate peak values for yarns without coating for operating temperatures near the indicated peak values, service life can be limited by chemical resistance,
equipment temperature, operating conditions and design. Please refer to our technical information on temperature resistance. Please consult us for use attemperature ranges near the limit values. ⁴⁾ Operating conditions, depending on medium.

24

SIGRAFLEX®
reinforced foil yarns

Material data of our SIGRAFLEX® APX2® foil yarn reinforced
with Inconel®¹⁾ 601 with a diameter of 100 µm²⁾
Typical properties

Test methods

Base material
Carbon content³⁾
Ash content³⁾
Sulfur content³⁾
Chloride content³⁾
Fluoride content³⁾
Halogen content³⁾
WeightTensile strength

ASTM D5373
ASTM C561
ASTM D4239
ASTM D4327
ASTM D4327
ASTM D4327
ASTM D1907
ASTM D2256

Weight loss from air(at 670 °C/ 1238 °F)³⁾

ASTM D7582
LECO TGAUnit

SIGRAFLEXAPX2 yarn

SIGRAFLEXAPX2 foil
%
≥ 98
%
≤2
ppm
< 300
ppm
≤ 25
ppm
≤ 10
ppm
≤ 70
g/m
3 or 5kg (lb)8 (18)%/hOver knitted wire reinforcement
The over knitted wire reinforcement is Inconel 601 which
provides the added tensile suitable for braiding. The wire also
possesses excellent high-temperature behavior and is suitably
lubricated with no detriment to the high-temperature performance and purity of the yarn. The yarn is also compliant withthe latest Shell MESC SPE 85/204 standard.
Broad portfolio of foil yarns
SGL Carbon has other foil based yarns with the same typeof reinforcement including SIGRAFLEX Z foil yarn with an ash
content of less than 0.15% for applications where a higher
degree of purity is required.

≤1

Other yarn types on request. Please contact us.
1)
Inconel® is a registered trademark of Special Metals Corporation.
2)
All values are measured in accordance with referenced test methods, typical,
non-binding and nominal. They may be subject to change and do not constitutean actual specification value.
3)
Graphite only

New developments in demand
We have responded to customer requests for high-temperature
resistant and high-purity braided packing yarns with outstanding mechanical properties by developing a new yarn based on
the SIGRAFLEX foil already established in the sealing market.
Maximum protection from oxidation
This has resulted in the best foil yarn on the market with regard
to oxidation resistance. The flexible expanded natural graphite
yarn SIGRAFLEX APX2, made of SIGRAFLEX APX2 foil with
Inconel®1 wire reinforcement.
The foil is made of premium expanded natural graphite andprovides maximum protection from oxidation (see page 12).
A higher bar
Our SIGRAFLEX APX2 yarn combines a number of unique properties including low friction, high flexibility, and excellent chemical resistance. Also the yarn is produced without an internal
carrier fiber and is without binders or adhesives, it does not
become brittle over time. Just like SIGRAFLEX APX2 foil theyarn exhibits high thermal conductivity so frictional generated
heat can be easily dissipated.

↑ SIGRAFLEX APX2 yarn provides maximum protection against oxidation.

Lowest weight loss with APX2 foil yarn
Behavior of different packings/yarns in TGA-dimensions at 482 °C (900 °F)
Weight loss [%]Temperature [° C]

25 —

— 500
Braided packing A

20 —Temperature
— 400

15 —

— 300
Braided packing B

10 —

— 200

5—

— 100
SIGRAFLEX APX2 yarn

0Time [h]

2

4

6

8

10

12

14

Unrivalled sealing | Carbon and graphite yarns

25

SIGRAFLEX®
oxidation-resistant yarn

Unrivalled combination of properties
Our new SIGRAFLEX OXR yarn is unique in many respects.
It has been specifically developed for high-temperatureapplications, and combines the advantages of graphitizedtextile yarns based on polyacrylonitrile with those of a
proprietary coating to enhance its temperature resistance.

High-purity – meets Shell specification
It is a high purity yarn with a carbon content of ≥ 99.5 %. The yarn
also has a low sulfur, fluorine and chlorine content.
This is a particular advantage for our customers, since SIGRAFLEXOXR yarn is the only yarn product on the market that meets therequirement of Shell specification 85/204 for graphite.

For high-temperature applications
The yarn is manufactured with a coating based on proven
SIGRAFLEX APX2 technology. Thanks to the considerably
improved oxidation resistance, it can be used in high-temperature applications. It furthermore fulfills the requirementsof packing manufacturers for low friction and high thermal
conductivity.

Yarns for unmet needs
The new yarn products from SGL Carbon close the existing gap
in the market for packing yarns that are high in purity as well
as resistant to high-temperatures.
Are you interested in trying out our yarn products?
Please contact us.

↓ SIGRAFLEX OXR yarn, our textile-graphite packing yarn with special
coating, developed for use in high-temperature applications.

Material data of our SIGRAFLEX® OXR yarn1⁾

Typical properties

Test methods

Units

Base material

Graphitized twisted
stretch-broken yarn

PAN

Coating
Carbon content²⁾
Ash content²⁾
Sulfur content²⁾
Chloride content²⁾
Fluoride content²⁾
Halogen content²⁾
Moisture content
Density
WeightTensile strength
Coating content
Twisting
Available twistings

ASTM D5373
ASTM C561
ASTM D4239
ASTM D4327
ASTM D4327
ASTM D4327
ASTM C562
ASTM D3800
ASTM D1907
ASTM D2256
ASTM D537
ASTM D1423

%
%
ppm
ppm
ppm
ppm
%
g/cm³
g/m
kg (lb)%
TPI (TPM)

Weight loss from air(at 670 °C/ 1238 °F)²⁾

ASTM D7582
LECO TGA%

oxidation resistantgraphite
99.5
0.15
≤ 100
≤ 25
≤ 10
≤ 100
0.1
1.6
1.6
45 (100)
15
1.75 (69)S, Z<2¹⁾ All values are measured in accordance with referenced test methods, typical,
non-binding and nominal. They may be subject to change and do not constitutean actual specification value.
²⁾	Equipment that fulfills Shell specification MESC SPE85/204(current version)

26

Smart
Solutions
Be it materials, components or production
processes, we focus our thinking and actions on
the customer and keep an eye on the big picture.
Our solutions already anticipate the future today.
The following examples show a selection of ourunique product range.

Mobility• Lightweight components and structural parts
based on fiber-reinforced composites for automotive and aerospace manufacture• Graphite anode material for lithium-ion batteries
in electric vehicles• Carbon-ceramic brake disks for sports cars andluxury sedans

Energy• High-temperature solutions based on specialty
graphites and fiber materials for the photovoltaic
industry• Carbon fiber materials for rotor blades• Gas diffusion layers for fuel cells• Systems for more efficient heat exchange andheat recovery• Carbon fibers for pressurized gas containers

Digitization• Carbon, graphite, and CFC components forpolysilicon and monocrystal pulling in thesemiconductor industry• High precision, coated graphite carriers for the
production of LEDs

→ State-of-the-art green production withthe world’s largest isostatic press

SGL Carbon

27

SGL Carbon
We are leaders in the development and manufacture of products based on carbon, graphite,
carbon fibers, and fiber-reinforced composites.
In partnership with our customers, we develop
intelligent, trendsetting, and sustainable
solutions that deliver a clear benefit.
With our in-depth material, engineering, andapplication know-how, we make a substantial
contribution to the major future topics mobility,
energy, and digitization.

Contact
Europe / Middle East / Africa
SGL CARBON GmbH
Werner-von-Siemens-Strasse 18
86405 Meitingen/Germany
sigraflex-europe@sglcarbon.com
Americas
SGL Technic LLC
28176 No. Avenue Stanford
CA 91355 Valencia/USA
sigraflex-americas@sglcarbon.com
Asia / Pacific
SGL CARBON Far East Ltd.
151, East Huan Cheng Road, Fengxian
Shanghai Industrial Development Zone
201401 Shanghai/PR China
sigraflex-asia@sglcarbon.com®

registered trademarks of SGL Carbon SE

This information is based on our present stateof knowledge and is intended to provide generalnotes on our products and their uses. It should
therefore not be construed as guaranteeing
specific properties of the products describedor 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“.
08 2022/0 3NÄ Printed in Germany

Graphite Solutions
SGL CARBON GmbH
Soehnleinstrasse 865201 Wiesbaden/Germany
www.sglcarbon.com/gs