Page 29 - Y-bearing-units

Seals
Fig. 3
The factors that influence the choice of the 1
most appropriate sealing method include:
• the peripheral speed at the sealing
counterface
• the friction in the seal and the resulting
temperature increase
• the operating environment, e.g. moisture,
dust or coarse contaminants
• the requirements regarding efficiency
a
The standard integral seal used in SKF
Y-bearing units provides good protection against
moisture and contaminants and also provides
reliable retention of the lubricant († fig. 3a).
The same applies to RS1 contact seals that are
integral to Y-bearings with a normal inner ring
in the 17262(00)-2RS1 and 17263(00)-2RS1
series († fig. 3b).
For more contaminated conditions, Y-bearing
units fitted with plain steel flingers outside the
integral seal should be used († fig. 3c). The
flingers have an interference fit on the inner ring
b
and considerably enhance the sealing effect
without increasing friction.
Where operating conditions are extremely
contaminated and long service life is required,
Y-bearing units with the highly efficient multiple
seal are recommended. Here, the sealing effi-
ciency of the standard integral seal is reinforced
by a steel flinger with a vulcanized sealing lip
(† fig. 3d).

c

d

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