Metal jacketed gaskets0 pages
Metal jacketed gaskets
Metal jacketed gaskets are proven sealing elements for use
in apparatus construction, which are however increasingly
being replaced at temperatures up to 550 °C by metal/softmaterial gaskets, such as grooved gaskets (see remarks
on the next page).
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At temperatures above 500 °C, such as in hot-blast areas,
metal jacketed gaskets can still hold their own against solid
metal gaskets such as weld ring gaskets.
Jacketed gaskets generally consist of a metal sheet coating
with an insert of RivaTherm Super, graphite or FA1) or some
layers of sheet metal.
The metal sheet coating should be as soft and flexible as
possible, but to prevent corrosion it is often made from a
stainless steel jacket in 1.4541 or 1.4571 steel.
The harder the jacket, the finer the flange roughness needs
to be.
Profile F8
picture 1
Metal jacketed gaskets for heat exchangers are supplied
with partitions in the model shown (picture 1).
Metal jacketed gaskets are also available as frames with
rounded corners.
In flanges with tongue and groove or male and female face
joints the jacketed gaskets should be fitted so that the tongue
and/or the male face is against the smooth side of the gasket (picture 2).
The inlay is selected according to the flange irregularities
that need to be covered. The better the quality and the evenness of the sealing surfaces, the harder the inlay can be.
There is a wide range of possible combinations; the following are extremes at both ends:
very soft:
Coating of aluminium,
inlay of graphite
very hard:
picture 2
Coating of stainless steel,
inlay of mica
Gasket limiting values
Surface pressure
limits for 20 °C
N/mm2
Surface pressure
limits for 300 °C
N/mm2
6,3
12,5
2,5
6,3
6,3
12,5
6,3
12,5
σϑ
30
100
60
150
70
180
100
250
60
180
200
500
σv
σϑ
(40)
(60)
70
120
80
150
115
200
70
150
200
350
Iron
Iron
12,5
25
Iron
Nickel
Graphite
25
50
from
to
σv
Graphite
Iron
Nickel
Graphite
µm
F3L
Copper
Brass
Graphite
Recommended max. roughness
(RZ) of the flange surfaces
Graphite
Aluminium
Materials
FW3
Stainless steel
F2 to F17
Profiles
Kempchen Dichtungstechnik GmbH · Tel. +49 (0)208 8482 0 · Fax. +49 (0)208 8482 285 · info@kempchen.de · www.kempchen.de
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Metal jacketed gaskets
1) Fibre sheets with binder
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