Page 38 - Rollingbearings

A.2 Tolerances

Tolerances Tolerance values Thrust bearings:

values for certain tolerance characteristics
A.2 Tolerance classes and the corresponding • Normal, P6 and P5 class tolerances
(table 10, page 46)
are speciied in ISO 492 (for radial bearings)
and ISO 199 (for thrust bearings). In 2014 Actual tolerance values are listed in the
these standards were aligned with general following tables. Tapered bore, taper 1:12:
ISO GPS (Geometrical Product Speciication) • Normal, P6 and P5 class tolerances
standards such as ISO 1101 and ISO 5459. Metric radial bearings, except tapered (table 11, page 47)
For additional information on ISO 492 and roller bearings:
ISO 199, and the changes that have been • Normal tolerances (table 2, page 38) Tapered bore, taper 1:30:
made to their previous editions, refer to • P6 class tolerances (table 3, page 39) • Normal tolerances (table 12, page 48)
the SKF e-learning platform • P5 class tolerances (table 4, page 40)
(skf.com/go/17000-learnGPS). Where standardized, the values are in
There are three common tolerance Metric tapered roller bearings: accordance with ISO 492, ISO 199 and
classes for SKF ball and roller bearings • Normal and CL7C class tolerances ANSI/ABMA Std. 19.2.
(table 1). (table 5, page 41)
The product sections for the various bear- • CLN class tolerances (table 6, page 42)
ing types provide information on compliance • P5 class tolerances (table 7, page 43)
with applicable tolerance classes. The toler- Inch radial bearings, except tapered roller Tolerance symbols
ance class of a bearing cannot always be
determined from its designation sufixes. bearings:
Where the tolerance class is standard for the • Normal tolerances (table 8, page 44) The tolerance symbols that we use are in
bearing, it is not speciied in the designation line with ISO 492 and ISO 199 and are
sufixes. Inch tapered roller bearings: explained in table 13, page 49. The symbols
For information about SKF bearings that • Normal, CL2, CL3 and CL0 class tolerances normally refer to dimensional tolerances,
have a tolerance class better than class 5, (table 9, page 45) only Kia, Kea, Sd, SD, Sia and Sea refer to
refer to the SKF catalogue Super-precision geometrical tolerances.
bearings or skf.com/super-precision.

Table 1
Common tolerance classes for SKF ball and roller bearings
ISO tolerance class SKF designation Description
sufix

Normal – Minimum standard for all SKF
ball and roller bearings.
Class 6 P6 Tighter tolerances than
Normal.
Class 5 P5 Tighter tolerances than
class 6.

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