Siemens Flender H2NV Series - Leakage; Leaktightness

50 / 62
BA 5060 EN 04/2011
9.2.1 Leakage / leaktightness
In DIN 3761 information is given on the subject of leakage on gear units. Based on this and building on the
extensive experience gained at Siemens and other FVA member companies, brief descriptions, required
measures and notes on this subject are listed in the following overview.
Table 12: Notes on the leaktightness of radial shaftsealing rings (RWDR)
Condition Description Measures Notes
Leaktight, dry No moisture to be seen on
radial shaft-sealing ring.
None
Leaktight, damp Film of moisture formed
functionally in the area of
the sealing edge but not
extending beyond the
bottom side of the radial
shaft-sealing ring.
Clean carefully only, if
dirt adheres; observe.
The radial shaft-sealing
ring often dries by itself in
further operation.
No reason for complaint
Leaktight, wet Moisture film extending
beyond the bottom side of
the radial shaft-sealing
ring but not dripping.
Wipe away with a
clean cloth; observe.
The radial shaft-sealing
ring often dries by itself in
further operation.
No reason for complaint
Measurable leak Small trickle to be seen on
the bottom side of the
radial shaft-sealing ring,
dripping.
If necessary, change
radial shaft-sealing
ring; identify possible
cause of radial shaft-
sealing ring failure and
rectify.
May be a reason for com
plaint.
One drop of oil a day is
acceptable.
Temporary leak Short-term failure of the
sealing system.
Wipe away with a
clean cloth; observe.
E.g. through small
particles on the seal edge,
which can be removed
again in further operation
No reason for complaint
Apparent leak Temporary leak. Wipe away with a
clean cloth.
Due mostly to excessive
grease filling between seal
and dust lip or oil secre
tions from the grease filling
of labyrinth seals.
No reason for complaint
Escaping oil mist from a ventilation valve or a labyrinth seal is functional and therefore
not a reason for complaint.