Page 227 - needle bearings

Roller followers: Yoke-type track rollers
NTN

Lubrication
The roller followers with synthetic rubber seal (with tail
code : LL) and the full complement roller type followers
are filled up with lithium soap base grease so that they
can be used in the temperature range of -25 to +100˚C.
Lubricant feeding and replenishing into the bearing are
done through an oil hole provided on the inner ring. In this
case, the inner ring must be fitted so the oil hole locates
within non-load area. For the full complement roller type
roller followers NATV, NACV, NUTR and NUTW with no
cage, it is necessary to shorten the grease replenishing
interval.
Further, a roller follower with cage and without seal is
not filled up with lubrication grease. When needing a
follower with grease-filled cage, feel free to contact NTN.

The outer ring outer surface of bearing and
the track surface must both be lubricated.
Failure to lubricate could result earlier in
damage of the bearing.

Track load capacity
Statically allowable maximum radial load on the contact
surface of track to track roller is referred to as "track load
capacity", which differs depending on the track hardness.
The track load capacity described in applicable
Dimensions Table is subject to track hardness HRC40. If
the hardness value is other than HRC40, multiply the
track load capacity in the Dimensions Table by the
adjustment factor G in Table 2, for determining the track
load capacity. However, the track load capacity shall be
C0r if the calculated track load capacity exceeds the basic
static load rating C0r of bearing.
Refer to page A-55 for the detail.

Table 2 Adjustment factor G
Hardness Adjustment factor G
HRC Cylindrical surface Spherical surface
20 0.37 0.22
25 0.46 0.31
30 0.58 0.45
35 0.75 0.65
40 1.00 1.00
45 1.40 1.70
50 2.00 2.80
55 2.80 4.70

B-165