Page 43 - SKF-bearing-housings

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Sealing solutions

The SKF three-barrier solution Fig. 11
For highly contaminated environments, SKF
recommends the three-barrier solution. This
cost-effective sealing solution can have a sig-
nificant impact on bearing service life as con- 1 2 3 3 2 1
taminants have to pass through three barriers
to reach the bearing († fig. 11):
st
• 1 barrier – external housing seal
• 2 barrier – housing grease
nd
• 3 barrier – integral bearing seal
rd
The SKF three-barrier solution consists of a
sealed SKF bearing, a housing with a 70 to 90%
grease fill, and labyrinth housing seals.
Sealed bearings have integral contact seals
that keep the lubricant in and contaminants
out of the bearing cavity during operation. The
seals also protect the bearing from the ingress
of contaminants during installation. Using a
sealed bearing also means that the grease
used to fill the housing and labyrinth seals is
independent of the lubrication requirements
for the bearing. Therefore, environmentally
friendly, biodegradable greases, such as
SKF LGGB 2, can be used to fill the housing
(† skf.com/lubrication).
When the SKF self-aligning bearing system
is used († page 41), the labyrinth seal for the
CARB toroidal roller bearing should be replaced
with a taconite seal.

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