Page 226 - needle bearings

Roller followers: Yoke-type track rollers
NTN

(2) Where the roller follower is mounted, locate the inner
Bearing Tolerances ring oil hole within the non-load area (load free side).
The respective dimensional accuracy, profile accuracy (Fig. 2)
and running accuracy of the bearing bore diameter (d), If the oil hole locates within the load area, it would
cylindrical roller outer diameter (D), and outer ring width cause shorter life.
(C) are as shown in Table 4.3 of Section 4. "Bearing
Accuracy" (page A-26). (Conforming to JIS Accuracy
Oil hole
Class-0)
On the other hand, the dimensional tolerances for
spherical roller outer diameter (D) and the roller inscribed
circle diameter (FW) of Type RNA22 are as shown in
applicable Dimensions Table.

Bearing fits and radial clearance
The tolerance range class of shaft against bearing with Load
inner ring shall be g6 (h6) and, where a shaft is used as
the direct raceway surface (Type RNA22), the tolerance Fig.2
range class of the shaft shall be k5 (k6). In general, the
outer ring is not fitted in a housing. Mounting relations
(3) Type NAŋŋŋŋ22LL and RNA22 are of separable type
and, hence, the outer ring is guided by flange or thrust
Table 1 Radial clearances
Unit: Жm washer mounted on shaft (pin). Therefore, the guide
Nominal roller Clearance
inscribed circle dia. surface must be finished more precisely than by lathe-
Fw (mm) C2 Ordinary C3 C4 turning and deburred completely for surface
smoothing. In addition, when the guide surface is not
over Incl. min max min max min max min max
hardened the outer ring must be guided at A-
3 6 0 10 3 17 15 30 20 40 dimension shown in Fig.3. When it is hardened, even
6 10 0 12 5 20 15 30 25 45
10 18 0 15 5 25 15 35 30 55 a little smaller guide surface can be used.
18 30 0 20 10 30 20 40 40 65
1
30 50 0 25 10 40 25 55 50 80 AʾʕʕʢDʴeʣ
2
50 80 0 30 15 50 30 65 60 100
80 100 0 35 20 55 35 75 70 115 For D and e dimensions refer to applicable Dimensions Table.

(1) The side face height in the roller follower mount must
be made larger than “e” dimension described in
applicable Dimensions Table. (Fig.1) In mounting,
chamfer the mounting surface at R as small as
possible (around 0.5ʷ45˚) and bring the inner ring
and the end face of side plate in precise contact with
one another.

Fig.3

In assembling this bearing, it must be handled with
good care to protect the seal lip from bending and flaw.

Side face
height
Where any of NTN roller followers was stub-
mounted, non-uniform load (bias load) could act
Fig.1 on the bearing, inversely affected by fitting
loose arising from further continued running.
Good care must be exercised of such fitting
loose, for stable running of the equipment.

B-164