Page 404 - SKF-bearing-housings

Split pillow blocks SAF and SAW series

Labyrinth seals is mounted for best contaminant exclusion,
Labyrinth seals are the standard sealing solu- the sealing effect can be enhanced by filling
tion for SAF and SAW housings. They are the seal cavity with grease. The designation
available in two variants depending on housing for the contact element is B 10724 followed
size: by a size code, for example B 10724-122.
• Labyrinth seals with the designation LER,
also called triple ring seals, are supplied Taconite heavy-duty seals
standard with small SAF housings (shaft Taconite seals consist of an inboard felt seal,
diameter ≤ 2 5 /8 inch). The rings form a a grease cavity and an outboard seal that is
multistage labyrinth seal with the housing available in two designs:
seal grooves. If operating conditions war-
rant it, the sealing effect can be enhanced • Seals in the TER series have a split contact
by filling the cavity between the housing and seal.
seal ring with grease. • Seals in the TER-V series have a V-ring seal.
• PosiTrac labyrinth seals, designation LOR,
are supplied standard with larger SAF (shaft To further protect against the ingress of con-
diameter ≥ 2 1 /8 inch) and all SAW housings. taminants, SKF taconite seals have a grease
These seals have an additional O-ring made fitting to purge grease and any trapped con-
of acrylonitrile-butadiene rubber (NBR) to taminants from the seal cavity, through the
make the labyrinth ring rotate with the outboard seal.
shaft.
Contact seals
Labyrinth rings with an internal Contact seals are solid seals that fit into the
contact element seal groove. Contact seals are available for
PosiTrac Plus seals consist of a PosiTrac laby- smaller housing sizes (SAF 513 and smaller)
rinth ring (designation LOR) and a contact ele- where PosiTrac Plus seals are not available.
ment made of acrylonitrile-butadiene rubber The designation for contact seals is B 9784
(NBR). The labyrinth ring is located on the followed by a size code, e.g. B 9784-15.
shaft and held in place by an O-ring. The con-
tact element is located in the seal groove in
the housing. It can be mounted either for best End plugs
contaminant exclusion or for best lubricant Housings at the end of a shaft should have
retention († fig. 6). When the contact element an end plug (end cover) that fits into the seal
Fig. 6

contaminant exclusion lubricant retention

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