Page 147 - Rollingbearings

Tolerances for bearing seats and abutments
Example Fig. 4
A deep groove ball bearing 6030 is to be Dimensional and total run-out tolerances zones
used in an electric motor The bearing
accommodates normal to heavy loads
(0,05 C < P ≤ 0,1 C), and requirements for
speed and precision are moderate An inter-
ference it on the shaft is required For this
it, the shaft diameter should be 150 m6�
The total radial run-out should be within 150,040 150,015
IT5/2 (from table 3: 18/2 = 9 µm), and the
total axial run-out of the abutment should
be within IT5 (from table 3: 18 µm) 0,009
The dimensional tolerance zone in grey
and the tolerance zone for the total radial Dimensional tolerance: 150 m6�
run-out in blue are shown in ig. 4 The blue Total radial run-out 9 µm
Actual dimensions of the shaft seat
zone can be located at any place within the
grey zone, but must not be wider than 9 µm

Table 3
Values of ISO tolerance grades
Nominal Tolerance grades
dimension IT3 IT4 IT5 IT6 IT7 IT8 IT9
> ≤ max
mm µm

1 3 2 3 4 6 10 14 25 Bearing interfaces
3 6 3 4 5 8 12 18 30
6 10 3 4 6 9 15 22 36
10 18 3 5 8 11 18 27 43
18 30 4 6 9 13 21 33 52 B.6
30 50 4 7 11 16 25 39 62
50 80 5 8 13 19 30 46 74
80 120 6 10 15 22 35 54 87
120 180 8 12 18 25 40 63 100
180 250 10 14 20 29 46 72 115
250 315 12 16 23 32 52 81 130
315 400 13 18 25 36 57 89 140
400 500 15 20 27 40 63 97 155
500 630 - - 32 44 70 110 175
630 800 - - 36 50 80 125 200
800 1 000 - - 40 56 90 140 230
1 000 1 250 - - 47 66 105 165 260
1 250 1 600 - - 55 78 125 195 310
1 600 2 000 - - 65 92 150 230 370
2 000 2 500 - - 78 110 175 280 440

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