General Data Bearing manufacturing precision Standardization Standard ISO 492 specifies the tolerances applicable to the dimensions and precision of rotation of metric series radial bearings. The dimensional tolerances defined by this standard bear the following symbols:
Internal master External master gauge subassembly gauge subassembly
r
B
B
r
T C
r D d
T2
T1
r D d
D
B
d
Tolerance classes defined by standard ISO 492: â—— The Normal class, which is that of all the standard bearings, and is not usually indicated in the bearing designation â—— The High precision classes which are, in ascending order of precision: ISO 6, ISO 5, ISO 4, ISO 2 These classes are indicated in the suffix added to the bearing reference. Example: C3 P5 Clearance category 3
ISO precision class 5
Standard ISO 199 sets the tolerances on thrust bearing dimensions. Standard ISO 582 sets the tolerances on bearing corner radii. The dimensions applicable to fillets and shoulders are indicated in the table of bearing characteristics. Standard ISO 5753 defines the tolerances on the radial clearance of the bearings.
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