Page 597 - Rollingbearings

Designs and variants
Sealed needle roller bearings with Relubrication
machined rings the grease in the bearing The assortment
includes:
features
• are available in the (R)NA 49 series with a • needle roller / full complement thrust ball
contact seal made of NBR (effective at bearings (ig. 28, page 591) SKF supplies needle roller bearings with
keeping the lubricant in and contaminants • needle roller / thrust ball bearings (ig. 30, different features to facilitate effective lubri-
out of the bearing) on one (designation page 591) cation and relubrication
sufix RS) or both sides (designation suf- • needle roller / cylindrical roller thrust
ix 2RS) (ig. 39) bearings (ig. 34, page 592) Drawn cup needle roller bearings
• have an inner ring that is 1 mm wider than
the outer ring, which maintains the effec- All double row drawn cup needle roller bear-
tiveness of the seals and simpliies the Greases for capped bearings ings have one lubrication hole in the outer
bearing arrangements even when small ring (ig. 11, page 585), as standard
axial displacements occur Needle roller bearings with one or two seals On request, SKF can supply any single row
are supplied greased The thrust part of drawn cup needle roller bearing for inside
Capped combined needle roller combined needle roller bearings with the diameters under the rollers F ≥ 7 mm with
w
bearings designation sufix Z is also supplied greased a lubrication hole in the outer ring (ig. 40)
They are illed with high-quality grease
SKF supplies certain combined needle roller (table 3) under clean conditions
bearings capped with a stamped steel cover The relatively large quantity of grease in
over the thrust part of the bearing (designa- the bearings means they can be operated for
tion sufix Z) The cover, which has no lubri- long periods before relubrication is required
cation holes, forms a gap-type seal to retain SKF recommends SKF LGWA 2 grease
(table 3), if relubrication is required

Fig. 39 Fig. 40
Sealed needle roller bearing with machined rings Single row drawn cup needle roller bear-
ing with a lubrication hole in the outer
ring 7

NA 49‥ RS NA 49…2RS

Table 3
Technical speciications of greases for capped needle roller bearings
Grease Temperature range 1) Thickener Base oil NLGI grade Base oil viscosity
type [mm 2 /s]
at 40 °C at 100 °C
–50 0 50 100 150 200 250 °C (105 °F) (210 °F)

Initial grease ill Lithium complex soap Mineral 2 160 15,5
LGWA 2 Lithium complex soap Mineral 2 185 15

–60 30 120 210 300 390 480 °F

1) Refer to the SKF trafic light concept (page 117)

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