Needle Roller Bearings - Ntn-snr.com

Appendix
NTN
Ordinary tolerance for straightness
Unit : mm
Classification by plate thickness 1.6 and less Over 1.6 3 incl. Over 3 6 incl.
Tolerance class
Cutting width division
Class-A Class-B Class-A Class-B Class-A Class-B
120 and less
Over 120 - 315 incl.
Over 315 - 1000 incl.
Over 1000 - 2000 incl.
Over 2000 - 3150 incl.
0.2
0.3
0.4
0.6
0.9
0.3
0.5
0.9
1.2
1.6
0.2
0.3
0.5
0.8
1.0
0.3
0.6
1.0
1.6
2.2
0.5
1.0
1.4
2.5
2.8
0.8
1.6
2.0
3.0
4.5
Remarks: Non-applicable to cutting width of less than 20 times as much as
plate thickness or cutting width of less than 30mm.
Ordinary tolerance for straightness
Unit : mm
Classification by plate thickness
3 and less Over 3 6 incl. Over 6 12 incl.
Tolerance class
Cutting width division
Class-A Class-B Class-A Class-B Class-A Class-B
120 and less
Over 120 - 315 incl.
Over 315 - 1000 incl.
Over 1000 - 2000 incl.
Over 2000 - 3150 incl.
0.3
0.6
1.6
3.0
4.5
0.5
1.2
3.0
6.0
9.0
0.5
0.8
2.0
4.0
5.5
1.0
1.6
3.0
6.0
9.0
1.6
2.0
3.0
6.0
9.0
Ordinary tolerance for sintered metal parts
JIS B 0411
This Standard specifies the ordinary tolerance which is
applied to the machining dimensions of sintered
mechanical parts and sintered oil-contained bearing, of
sintered metal parts, but excluding machining methods
other (e.g. cutting, etc.) than the machining method
specific for sintered metal parts.
Ordinary tolerance is applied to the dimensions for
which special accuracy is not required functionally and,
therefore, applicable tolerances are indicated in batch,
without individual indication of them, in relevant
specification, drawings, etc.
Ordinary tolerance shall be indicated by either one of
the following methods (1) and (2).
(1) Numerical value table for each dimensional division
(2) Applicable Standard No. and tolerance class
Ex. JIS B0411, Fine Class
Definition of terms: The terms used in this Standard are
as defined below.
(1) Width: Perpendicular dimension against
compressing direction in compressive molding of
powders, as illustrated in Fig. a.
(2) Height: Dimension parallel to compressing direction
in molding of powders, as illustrated in Fig. b.
Ordinary tolerance for width
class
Fine class
Dimensional division
6 and less
0.05
Over 6 - 30 incl. 0.1
Over 30 - 120 incl. 0.15
Over 120 - 315 incl. 0.2
Ordinary tolerance for height
class
Fine class
Dimensional division
6 and less
0.1
Over 6 - 30 incl.
0.2
Over 30 - 120 incl. 0.3
Unit : mm
Medium class Coarse class
0.1 0.2
0.2 0.5
0.3 0.8
0.5 1.2
Unit : mm
Medium class Coarse class
0.2 0.6
0.5 1
0.8 1.8
Compressing
direction
Compressing
direction
b
a1
a2
a1
a2
b1
b2
a3
a3
Class: The ordinary tolerance class shall be three classes of “Fine
Class”, “Medium Class” and “Coarse class”.
Reference: The numerical values every each class of “Fine Class”,
“Medium Class” and “Coarse class” match “Fine Series,
Medium Series and Coarse Series specified in ISO 2768
(Permissible machining variations in dimensions without
tolerance indication)
C-13