NTN - Large Bearings

Cylindrical Roller Bearings
2. Dimensional Accuracy/Rotation Accuracy
Refer to Table 3.3 (Page A-12,13)
3. Recommended Fitting
Refer to Table 4.2 (Page A-24)
4. Bearing Internal Clearance
Refer to Table 5.5 and 5.6 (Page A-31, 32, 33)
5. Permissible slant angle
It varies according to the bearing type and internal
specifications, the values in the table below are widely
used to avoid edge loads under general load conditions.
When the width series is 0 or 1 ⋯⋯0.001 rad (3.5')
When the width series is 2 ⋯⋯⋯⋯0.0005 rad (1.5')
Double row cylindrical roller bearing 1 ⋯0.0005 rad (1.5')
1 This is no applied to high accuracy bearings which are
used as the main shaft of machine tools.
Table 5 Tolerance of inscribed circle diameter Fw of rollers and
circumscribed circle diameter Ew of rollers for
compatible bearings.
Unit m
d mm ∆Fw ∆Ew
over Incl high low
50
120
200
250
315
400
500
630
800
1,000
1,250
120
200
250
315
400
500
630
800
1,000
1,250
1,400
+ 20
+ 25
+ 30
+ 35
+ 40
+ 45
+ 70
+ 80
+ 90
+105
+125
- 20
- 25
- 30
- 35
- 40
- 45
- 70
- 80
- 90
-105
-125
∆FwDimensional difference of inscribed circle diameter of rollers. 2
∆EwDimensional difference of circumscribed circle diameter of rollers. 2
2 Regulation range of JIS is d 500mm for ∆Fw, and d 400mm for ∆Ew.
0
0
0
0
0
0
0
0
0
0
0
low
0
0
0
0
0
0
0
0
0
0
0
high
Table 6 Radial internal clearance of Model SL cylindrical roller bearing.
Unit m
Nominal bore diameter
CN (Normal) C 3 C 4
dmm
over Incl min max min max min max
30 50 20 75 40 95 55 110
50 80 30 90 55 115 75 135
80 120 35 105 80 150 105 175
120 180 60 150 110 200 150 240
180 250 90 190 155 255 205 305
250 315 110 225 195 310 255 370
315 400 140 265 245 370 320 445
400 500 180 320 300 440 395 535
6. Radial internal clearance of the Model
SL cylindrical roller bearings.
Table 6 lists the radial internal clearance values of the
Model SL cylindrical roller bearings.
7. Recommended fit of the Model SL
cylindrical roller bearings, and selection
of the radial internal clearance.
Table 7 lists the recommended fit for outer ring rotation
such as sheaves and wheels, Table 8 lists the relation
between the fitting and the radial internal clearance.
For assembling and disassembling the bearing, it is
necessary to evenly load around the circumference of the
raceway end on the fitting side.
8. General Operating Cautions
Slippage between the rollers and raceways may occur
when bearings are operated under small loads (about Fr
0.04Cor) and may cause smearing. This is most apparent
when using large size cylindrical roller bearings due to the
large cage mass. Please consult NTN Engineering for further
details.
Table 7 Recommended fit
Outer ring
rotating
load
Conditions
Heavy load with a
thin walled housing.
Normal load, heavy
load
Light load,
changing load
3 Be sure to use N7 for sheaves.
Tolerance range
class of shaft
g6 or h6
Tolerance range
class of housing
P7
3
N7
M7
Table 8 Relation between fit and radial internal clearance.
Shaft fit
g 6
h 6
j 5
j 6
k 5
k 6
m 5
m 6
n 5
n 6
p 6
Housing fit
G 7 H 6 J 6 J 7 K 6 K 7 g 6 M 6 M 7 N 6 N 7 P 6 P 7
CN(Normal) C 3
C 3
C 4
C 4
Note: When the shaft fit is g6, housing fit is N7(N6) and used at low
speed (for sheaves), apply CN(normal) clearance.
B-39