Page 778 - Rollingbearings

9 Spherical roller bearings
Annular groove and lubrication Grease life for sealed bearings
holes The seals are itted in a recess on the outer
ring and seal against the inner ring (ig. 8) The grease life for sealed bearings is pre-
On larger bearings, the seals are ixed by a sented as L , i e the time period at the end
10
• CC and CA design bearings are available retaining ring (ig. 9) of which 90% of the bearings are still reliably
with an annular groove and three lubri- Bearings sealed on both sides are lubri- lubricated, and depends on the load, operat-
cation holes in the outer ring (designation cated for the life of the bearing and are vir- ing temperature and speed value It can be
sufix W33) or three lubrication holes in tually maintenance-free (Grease life for obtained for bearings with standard SKF
the outer ring (designation sufix W20) sealed bearings) They are illed with one of LGEP 2 grease (designation sufix VT143)
(ig. 7) the following greases (table 1): from:
• E design bearings have an annular groove
and three lubrication holes as standard • SKF LGEP 2 grease (designation sufix • diagram 1, for light load (P ≤ 0,067 C)
(ig. 6, page 775) This feature is not iden- VT143) as standard • diagram 2, page 778, for normal load
tiied in the bearing designation (no desig- • SKF LGHB 2 grease (designation sufix (P ≤ 0,125 C)
nation sufix) GEM9) or LGWM 2 grease (designation
sufix GLE) on request The grease life is valid under the following
operating conditions:
For additional information about greases,
Sealed bearings refer to Selecting a suitable SKF grease, • horizontal shaft
page 116 • inner ring rotation
• have the same features and internal • operating temperature within the green
design as open spherical roller bearings temperature zone of the grease (table 1)
• are available with a cylindrical bore as • stationary machine
standard • low vibration levels
• are supplied grease lubricated and should • load ratio F /F ≤ e (product table,
a
r
not be washed page 792)
• are equipped with an annular groove and • rotational speed below the limiting speed
three lubrication holes in the outer ring, (product table) and below the limits listed
except for those with the designation in table 2, page 778
sufix W
• are itted with a contact seal, on one or For other operating conditions, the grease
both sides, made of one of the following life can be estimated by multiplying the relu-
materials: brication interval for open bearings (Esti-
– sheet steel reinforced NBR (designation mating the relubrication interval for grease,
sufix CS or RS) page 111) by a factor of 2,7
– sheet steel reinforced HNBR (designa-
tion sufix CS5 or RS5)
– sheet steel reinforced FKM (designation
9 sufix CS2)

Fig. 7 Fig. 8 Fig. 9
Annular groove and lubrication holes Seals itted in outer ring recess Seals ixed by a retaining ring

W33

W20

776