what is mastite non-asbestos ?

http://www.kmgasket.co.krhttp://www.kmgasket.co.kr

한국매스타이트㈜한국매스타이트㈜



WHAT ISMASTITE

NON-ASBESTOS ?



WHAT ISMASTITE

NON-ASBESTOS ?

MASTITE NON-ASBESTOSARE MATERIALSTHAT HAVE BEEN

SPECIALLY DEVELOPEDTO COMBAT THE

DANGERS OFASBESTOSIS



PLEASE LET ME INTRODUCE MYSELFMY NAME IS

MR. MASTITEI WILL BE TALKING TO

YOU ABOUT:HEALTH & SAFETY

ASBESTOS ‘V’ NON-ASBESTOSMATERIAL PROPERTIES



DID YOUKNOW



ALSO



AND



WHAT ARE THEDIFFERENCESBETWEEN ASBESTOSAND NON-ASBESTOS



WHAT ARE THEDIFFERENCESBETWEEN ASBESTOSAND NON-ASBESTOS

GOOD QUESTION



ASBESTOS NON- ASBESTOS

TEMPERATURE: approx.500 apprx.300

FIBRE CONTENT up to 70% up to 40%

COMPRESSION approx.10% approx. 15%

SAFETY DANGEROUS safer alternative

COST appox. X 2



Non-AsbestosThere is no one fibre that can replacethe asbestos fibre at present. Mostmanufacturers use a combination of:Aramid, Glass, Mineral and Carbon.

It is also know that there are manymore compositions used when producing Non-asbestos sheeting thanwhen producing asbestos.



WHAT PROPERTIESMAKE

AGOOD SEAL ?


한국매스타이트㈜한국매스타이트㈜TYPICAL FLANGE JOINT

Sealing Properties required :

Good compressionLow creep Temperature resistanceChemical resistanceLow permeabilityRecovery


한국매스타이트㈜한국매스타이트㈜FLANGE JOINT SECTION

External Pressure (Bolt Torque )

Internal Pressure.Resistance to Fluidor Gas being handled.

Resilience to Flange Movement

IDEAL GASKET:

High Compressibility with alow creep factorgiving good resistanceto temperature& chemicals/gases. It is always better to have the thinnest gasket possiblehowever consideration offlange smoothness& distortion should be made when calculatingthe Gasket thickness.

K.M.G. 한국매스타이트㈜


한국매스타이트㈜한국매스타이트㈜POSSIBLE LEAK PATHS

Permeability throughthe Material

Irregularities of theFlange surface & flangedistortion.

Giving rise to possible leakage


한국매스타이트㈜한국매스타이트㈜GUIDE TO CALCULATING GASKET THICKNESS

Measure surface finish& flange distortion.Take the greater of

the two = xASBESTOSTypical compressionvalue of Asbestos9%=y

NON-ASBESTOSTypical compressionvalue of Non-Asbestos13%=y

X Times 2 x 100 y

GasketThickness

Eg.Asbestos0.135 x 2 x100 y(9)

3mm

Eg.Non-Asbestos0.135 x 2 x100 y(13)

2mm


한국매스타이트㈜한국매스타이트㈜GASKET CREEP

Gasket creep occurs whenexternal stress(pressure)and temperature is appliedto the gasket.

The effect of gasket creepis a thickness decrease in the gasket material coupledwith the gasket spreadinginto the inner flange & the outer.

In extreme cases gasketcreep can result in a completebreakdown of the material.








External Pressure& temperature cause gasket

thickness decrease& creep









This then reducesthe external

downward pressurecreating potential

leak paths




Generally the higher thecompressibility of a materialthe better the initial sealingproperties.However high compressibilitycan sometimes give high levelsof GASKET CREEP which willcause the gasket to leak orin some cases fail completely.

So far we can conclude that material with good compressibility and low creepis desirable.

GOOD COMPRESSIBILITY& LOW CREEP

= GOOD SEALABILITY


한국매스타이트㈜한국매스타이트㈜GASKET RECOVERY

Gasket Recovery is veryimportant when the materialis under cyclic loading.For example when a flangeis heated expansion occurscausing increased pressureon the gasket resulting in thegasket reducing in thickness.When the loading (pressure)is reduced the gasket shouldrecover its thicknesssufficiently enough as to not impair its sealing abilities.

External Pressure

External Pressure




The flange expandscausing increasedpressure on the

gasket

IncreasedExternal Pressure

IncreasedExternal Pressure




External Pressure

External Pressure

Gasketrecovery



TOTAL TIME 5 HOURS ( SEGMENTS 30 MINUTES )

HOT CREEP TEST

MATERIAL : MASTITE NASB 9 2.0mm NON-ASBESTOS

TEST : 5 HOUR HOT CREEP @ 50MPa 300 CRESULT : 8.5% CREEP 22% COLD COMPRESSION

TH

ICK

NE

SS

DE

CR

EA

SE

mm

TE

MP

ER

AT

UR

E °

C

30 60 90 120 150 180 210 240 270 300

STANDARD: DIN 28090-1 (Modified)



TH

ICK

NE

SS

DE

CR

EA

SE

mm

TE

MP

ER

AT

UR

E °

C

30 mins

COLD COMPRESSION

MATERIAL : MASTITE NASB 9 2.0mm NON-ASBESTOS

TEST : 30 MINUTES COLD COMPRESSION @ 50MP

RESULT : 8.5% CREEP 22% COLD COMPRESSION

Decrease inMaterialThicknessequals 0.44mmequals 22%

STANDARD: DIN 28090-1 (Modified)



1) What temperature is required ?

2) What internal/external pressure ?

3) Flange irregularities ? Decide on compressibility & thickness of material

4) Does the material have a low creep value ?

5) Is the material resistant to the medium being sealed?

6) Will the gasket be under cyclic loading ? Check stress relaxation & recovery

CHECK LIST

Remember !!Reduce thicknesswhen usingnon - asbestos



FINALLY

Mr

Mastite

what is mastite non-asbestos ?

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