HNBR Matrix✽ Long-term flexible layer✽ High thermal stability✽ Reduced brittleness

✽ Oxidation and ageing resistant✽ Optimised curing system

NBR Matrix✽ High network density✽ Low creep under load

✽ High strength✽ High permissible load

The layers of the structure arecharacterised by the selection ofelastomers. Since at least one of thelayers contains a different elastomer(compared with the standardelastomers like NBR, SBR, etc.) thedecomposition and ageing processesassociated with conventional fibrematerials i.e. post curing, thermooxidative decomposition, degradationof the polymer chains etc. dependingon application, can be suppressed.

The Multi-Layer structure makesit possible to develop materials withnew property profiles. The layerscontaining the special elastomersremain flexible over longer periodesthan standard materials even at hightemperatures and are therefore able to compensate for dynamic loadfluctuations induced by the flange.This flexibility suppresses thecreation of micro crevices, which areresponsible for gasket leakage.

The layers containing standardelastomers are better able to resistdeformation under load due to theformation of a denser network.

The gasket therefore remainsflexible but still retains its strength.

* Detailed information about the Multi-Layer concept can

be supplied separately on request.

For quite some years the sealingindustry in general has been un-able to offer an adequate substitutefor the KLINGERit gasket. Thisgasket, because of its absence ofembrittlement at high tempera-tures was extremely successful.

We are pleased to advise thatexactly 110 years after the inven-tion of KLINGERit, KLINGER isable to re-confirm its leading posi-tion in the field of fibre reinforcedgaskets with the latest developmentKLINGER®top-sil-ML1.

This new concept in materialtechnology* ties up with theperformance benchmark set byKLINGERit gaskets.

Multi-Layer property profile✽ Extended service life and

less leakage in spite of high temperatures

✽ Higher residual flexibility✽ Delayed ageing✽ Less creep✽ High permissible load

KLINGER top-sil-ML1Unique Multi-Layer

material concept

®

Tightness behaviour in saturatedsteamThis test is an excellent method totest the decomposition of elastomerbounded sealing materials within areasonable time. The appliedtemperature of 320°C coupled withan environment of saturated steamat around 120 bar provides astringent test for the elastomers.The arduous nature of the test con-ditions is designed to promote de-composition of the samples, allowingan assessement of ageing resistanceof the Multi-Layer materials.By these extrem testing conditions adifferentiation of different gaskettypes becomes possible.

A sudden pressure loss withinthe test rig chamber indicates eithersteam escape through crevices withinthe material or destruction of the testspecimen. Both effects result fromembrittlement of the gasket due todegradation of the elastomers.

The time before the pressuredrop occurs can be seen as ameasurement of the ageing resistanceof the gasket. In order to quantify theeffects caused by the formationof micro crevices, the test rig waspressurised with 40 bar nitrogen tomeasure the leakage rate at roomtemperature following the steam test.By this method a direct correlationcan be defined between the ageing ofthe gasket and its leakage rate.

The Multi-Layer materialguarantees the user significantlylower emissions over a longerservice life at elevatedtemperatures.

Tightness behaviour in saturated steam

Elastic propertiesTo evaluate flexibility potentials ofsealing materials the three pointbending test is often used to assessthe flexibility of compressed fibrematerials. Trials with conditionedtest specimens provide an indicationof the level of embrittlement andtherefore the ageing behaviour of theelastomers employed.

Prior to the bending testssamples were conditioned asfollows.

✽ Hot air for 168 h at 160°C and✽ Saturated steam for 168 h

at 185°C

Steam hammer often occurs insteam applications and leads todamage of the sealing materials.A more flexible gasket will thereforecontribute to a safer and morereliable flange connection.

The novel Multi-Layer materialconcept significantly increasesageing resistance at elevatedtemperature when compared withconventional materials.

With this concept, it is possibleto minimise all the undesirableproperty changes associated withtraditional compressed fibre materialssuch as embrittlement, formation ofcrevices and increased leakage.

Incorporation of specialelastomers into separate layers withinthe Multi-Layer structure ensures thata longer service life and increasedtemperature resistance can beexpected.

Tests have shown that such acombination of properties cannot beachieved through homogenuousmixing of two elastomers.

Elastic properties

KLINGER top-sil-ML1A milestone for

fibre reinforced gaskets

®

NBR Multi-Layer

high

er fl

exib

ility

Elongation %

Bend

ing

stren

gth

NBR Multi-Layer

Time d

Inter

nal p

ress

ure

extendedservice life

KLINGER top-sil-ML1Flanged joint integrity

®

Maximum permissible surfacepressure σBO under operatingconditions acc. DIN 28090 – 1The maximum surface pressure underoperating conditions is the maximumallowable surface pressure on theeffective gasket area under serviceconditions that can be applied to thegasket before unacceptable relaxationof the flanged joint occurs and/or thegaskets are destroyed.

The diagram above shows this values for different gasketthicknesses.

Min. surface pressure σVUfor tightness classes L = 1.0, L = 0.1 and L = 0.01 in accordance to DIN 28090The minimum surface pressure is theminimum surface pressure that shouldbe applied to the gasket to achievethe necessary tightness requirements.

The value must be sufficient tocompress the material into the flangeimperfections, reduce the materialsporosity and also counteract therelease of load due to the internalpressure.

The diagrams below show theminimum gasket stress required toachieve the relevant tightness classesas a function of thickness.

0

20

50

40

30

60

90

10011

10 20 30 40 50

1.0 mm

1.5 mm

2.0 mm

3.0 mm00

0

20

50

40

30

60

90

10011

10 20 30 40 50

1.0 mm

1.5 mm

2.0 mm

3.0 mm00

0

20

50

40

30

60

90

10011

10 20 30 50

1.0 mm

1.5 mm

2.0 mm

3.0 mm00

0

100

250

200

150

350

300

450

400

500

50

0

100 200 300 400

3.0 mm

Tightness class L= 0.1 allows a maximum leakage of

0.1 mg nitrogen per second per meterof gasket length (mg/s x m)

Modulus of elasticity ED inaccordance to DIN 28090This diagram outlines the modulus ofelasticity compared to the surfaceload. The curves describe thebehaviour at ambient temperatureand at 150°C.

KLINGER top-sil-ML1Flanged joint integrity

Important points to be observedWith heightened awareness of safetyand environmental issues, reducingleaks from flanged assemblies hasbecome a major priority for industry.It is therefore important for com-panies who use gaskets to choose thecorrect material for the job and installand maintain it correctly to ensureoptimum performance.

A flanged joint will remain tightas long as the surface pressure inservice is higher than the minimumsurface pressure required to achievethe necessary levels of tightness but is lower than the maximumpermissible surface pressure. Butincreasingly high demands on thetightness requirements for flangedjoints (e.g. Tightness class L 0.1 inaccordance with DIN 28090)necessitate the application of highloads on the gasket material in orderto meet these stringent requirements.

If the gasket is to be subjected to non-static loading and stress fluctuations due to temperature and pressure cycling, it is advisableto select a gasket material which is less prone to embrittlement with increasing temperatures (e.g.KLINGERgraphite laminate,KLINGERtop-chem or KLINGERtop-sil). In cyclic loading conditions werecommend a minimum surfacestress of 30 MPa and that the gasketshould be as thin as is practicable.

For safety reasons never re-usegaskets.

Gasket load 10 MPa

Gasket load 20 MPa

Gasket load 30 MPa

1.0

0.1

5020

100

4060

80

100 150 200 250 300

00

Temperature °C Gas pressure bar

Leak

mg/

(sm

)

Leak

mg/

(sm

)1.0

0.1

1.0

0.1

5020

100

4060

80

100 150 200 250 300

00

Temperature °C Gas pressure bar

Leak

mg/

(sm

)

Leak

mg/

(sm

)

1.0

0.1

1.0

0.1

5020

100

4060

80

100 150 200 250 300

00

Temperature °C Gas pressure bar

Leak

mg/

(sm

)

Leak

mg/

(sm

)

1.0

0.1

High temperature tightnessHigh temperature tightness ismeasured by means of the KlingerHot Compression test under definedconstant gasket load and temperaturewith increasing internal pressuresusing nitrogen as test fluid.

Stabilisation time for eachreading is two hours and a new testspecimen is used for every gasketload and temperature.

The tightness is analysed with amassflow meter. The pressure iscontrolled by pressure controller.

®

The following guidelines aredesigned to ensure the optimumperformance of our gasket materials:

1. Choosing the gasketThere are many factors which must be taken into account when choosinga gasket material for a given appli-cation including temperature,pressure and chemical compatibility. Please refer to the information givenin our brochure or, for advice to oursoftware program KLINGER ®expert. If you have any questions regardingthe suitability of material for a givenapplication please contact KlingerTechnical Department.

2. Gasket thicknessThe gasket should be as thin astechnically practical. To ensureoptimum performance a minimumthickness/width ratio of 1/5 is re-quired (ideally 1/10).

3. Flange condition Ensure all remains of old gasketmaterials are removed and the flangesare clean, in good condition andparallel.

4. Gasket compoundsEnsure all gaskets are installed in a dry state, the use of gasket compounds is not recommended asthis has a detrimental effect on thestability and load bearing charac-teristics of the material. In itsuncompressed form the gasket canabsorb liquid, and this may lead tofailure of the gasket in service. To aidgasket removal Klinger materials arefurnished with a non sticking finish.

In difficult installationconditions, separating agents such as dry sprays based on molybdenumsulphide or PTFE e.g. KLINGERflonspray, may be used, but only inminimal quantities. Make sure thatthe solvents and propellants arecompletely evaporated.

KLINGER top-sil-ML1Installation instructions

5. Gasket DimensionsEnsure gasket dimensions are correct.The gasket should not intrude into thebore of the pipework and should beinstalled centrally.

6. BoltingWire brush stud/bolts and nuts (if necessary) to remove any dirt onthe threads. Ensure that the nuts canrun freely down the thread before use.

Apply lubricant to the bolt andto the nut threads as well as to theface of the nut to reduce friction whentightening. We recommend the use of a bolt lubricant which ensures afriction coefficient of between 0.10 to 0.14.

7. Joint AssemblyIt is recommended that the bolts aretightened using a controlled methodsuch as torque or tension, this willlead to greater accuracy andconsistency than using conventionalmethods of tightening. If using atorque wrench, ensure that it isaccurately calibrated.

For torque settings please referto the KLINGER ®expert or contact ourTechnical Department which will behappy to assist you.

Carefully fit the gasket intoposition taking care not to damagethe gasket surface.

When torquing, tighten bolts inthree stages to the required torque asfollows:

Finger tighten nuts. Carry outtightening, making at least threecomplete diagonal tighteningsequences i.e. 30%, 60% and 100%of final torque value. Continue withone final pass – torquing thebolts/studs in a clockwise sequence.

8. RetighteningProvided that the above guidelinesare followed retightening of thegasket after joint assembly shouldnot be necessary.

If retightening is considerednecessary, then this should only beperformed at ambient temperaturebefore or during the first start-upphase of the pipeline or plant.Retightening of compressed fibregaskets at higher operating tem-peratures and longer operating timesmay lead to a failure of the gasketconnection and possible blow out.

9. Re-useFor safety reasons never re-use agasket.

Powerful sealing calculation with online help on CD-ROM

®

KLINGER top-sil-ML1Technical data

min50 MPa, 16h/ 175°C50 MPa, 16h/ 300°C40 MPa, 16h/ 300°Cthickness decrease at 23°Cthickness decrease at 300°C

DIN 28090-1VDI 2440DIN 28091-2DIN 28091-2DIN 28091-2DIN 28091-2DIN 28091-2 oil JRM 903: 5 h/150°Cfuel B: 5 h/23°C

Typical valuesCompressibility ASTM F 36 JRecovery ASTM F 36 J Stress relaxation DIN 52913

Stress relaxation BS 7531Klinger cold/hot compression50 MPa Tightness according DIN 3535/6Tightness class LSpecific leakrate λCold compression Cold recoveryHot compression Hot recoverySpring back RThickness increase after fluid immersion ASTM F 146 Density

9> 50

3428–8

15< 0.1

0.1–

6 - 93 - 5 < 15

1.30.026

48

1.7

%%

MPaMPaMPa

%%

mg/s x m

mbar x l/s x m% % %%

mm%%

g/cm3

■ UsesMulti-Layer sealing material withextended service life and improvedflexibility at higher temperatures.Suitable for use with oils, water,steam, gases, salt solutions, fuels,alcohols, moderate organic andinorganic acids, hydrocarbons,lubricants and refrigerants, foodindustry. Outstanding performance inmany applications.

■ Dimensions of the standard sheetsSizes:1000 x 1500 mm, 2000 x 1500 mm.Thicknesses:0.8 mm, 1.0 mm, 1.5 mm,2.0 mm, 3.0 mm;other thicknesses and sizes on request.Tolerances:thickness ±10%, length ± 50 mm,width ± 50 mm.

■ SurfacesKLINGERSIL® gasket materials aregenerally furnished with surfaces oflow adhesion. On request, graphitefacings and other surface finishes onone or both sides are also available.

■ Function and durabilityThe performance and service life ofKLINGER gaskets depend in largemeasure on proper storage andfitting, factors beyond the manu-factor’s control. We can, however,vouch for the excellent quality of ourproducts.

With this in mind, please alsoobserve our installation instructions.

■ Tests and approvalsBAM, DIN-DVGW, KTW, WRC and TA-Luft (Clean air)approvals in preparation.

®

KLINGER®top-sil-ML1 meets the requirements of BS 7531: Grade X

Rich. Klinger Dichtungstechnik GmbH & Co KGAm Kanal 8-10A-2352 Gumpoldskirchen, AustriaTel ++43 (0) 2252/62599-137Fax ++43 (0) 2252/62599-296e-mail: mueller@klinger.co.athttp://www.klinger.co.at

Subject to technical alterations. Issue: July 2004

Certified according to DIN EN ISO 9001:2000

Powerful sealing calculation with online help on CD-ROM