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Alvin Ramos12/333280/TK/39693GasketGasket is a mechanical seal
which fills the space between two or more mating surfaces,
generally to prevent leakage from or into the joined objects while
under compression.
How gasket works
Air gap through rough surfaceAdding GasketPressurePressure
Need GasketPressure for gasket should be limited to 33% of the
elastic limit of the material for temporary seams and 66% for
permanent closures.Gasket are held in place by sidewall friction,
metalized adhesive, and soldering.Gasket pressure may range from
0,8 to 8 kg/cm2, with 1,5 kg/cm2 being a normal value.Gasket
Material Compressed Knitted WireAdvantages :Most resilient
all-metal gasketMost Points of contactAvailable in variety of
thickness and resilienceIn combination with neoprene and
siliconLimitation :Not available in sheetMust be 1 mm or
thicker
Gasket Material (cont)Brass or beryllium copper with punctured
nail holesAdvantages :Best breakthrough of corrosion protection
filmsLimitation :Not truly resilient or generally reusable
Gasket Material (cont)Oriented Wires in rubber or
siliconAdvantages :Combines fluid and RF sealCan be effective
against corrosion films if ends of wire are sharpLimitation :Might
result in large size gasket for given effectiveness
Gasket Material (cont)Aluminum screen impregnated with
neopreneAdvantages :Combines fluid and conductive sealThinnest
gasketCan be cut to intricate shapesLimitation :Very low
resiliency
Gasket Material (cont)Soft MetalsAdvantages :Cheapest in small
sizeLimitation :Cold flowsLow resiliency
Gasket Material (cont)Metal over rubber Advantages :Take
advantage of the resiliency of rubberLimitation :Foil cracks or
shifts positionGenerally low insertion loss, yielding poor RF
properties
Gasket Material (cont)Conductive RubberAdvantages :Combines
fluid and conductive sealLimitation :Practically no insertion
lossGiving very poor RF properties
Gasket Material (cont)Contact FingersAdvantages :Best suited for
sliding contactLimitation :Easily damagedFew points of contact
Common Errors in Gasket Design
Common Errors in Gasket Design (Cont)
Common Errors in Gasket Design (Cont)
