FAG machine tool spindle bearing size and geometric tolerance measurement method

Dimensional and geometrical tolerances Unless specifically stated otherwise, FAG radial bearings have a tolerance in accordance with DIN 620-2 (ISO 492) and thrust rolling bearing tolerances in accordance with DIN 620-3 (ISO 199), Fig. 1. The accuracy level is PN. For higher precision bearings, tolerance values ​​are limited to P6, P5, P4, and P2. Refer to pages 29 to 32 for data sheets for various tolerance levels. FAG high-precision bearings High-precision bearings do not use standard tolerance classes but are produced according to tolerance classes P4S, SP and UP. These tolerances are listed in the product description of the JAF Precision Bearings catalogue, see TPI120, High-Precision Bearings with Combined Loads.
  Measuring methods The testing method for rolling bearings is in accordance with DIN 620-1 and ISO 1132-2. More detailed information on the measurement method is given in TPI138, THK Rolling Bearing tolerances, definitions and measurement criteria. TPI bearing samples can be ordered through the internet.
  FAG machine spindle bearing tolerance symbols and definitions Tolerance symbols Tolerance characteristics according to DIN 1132 and DIN 620
d Nominal bearing diameter

Dmp average hole diameter deviation in a single plane

D1mp Deviation of the average diameter at the large end of a tapered bore
Vdsp single hole diameter variation in a single plane
Vdmp average hole diameter variation
D bearing nominal outside diameter

Dmp average in-plane deviation of a single plane
VDsp single outer diameter variation in a single plane
VDmp average outside diameter variation
B Inner ring nominal width

Bs single inner ring width deviation
VBs inner ring width variation
C Nominal width of outer ring

Cs single outer ring width deviation
VCs outer ring width variation
Kia Ring Bearing Radial Runout
Kea Radial runout of bearing outer ring
Sd inner ring end face inner hole runout
Bus surface of outer surface of SD outer ring beats to the reference end surface
Axial runout of Sia bearing inner ring
Axial runout of the outer ring of Sea Bearings
Thickness variation of Si shaft
Se seat thickness variation
T one-way thrust bearing nominal height
T Tapered Roller Bearing Assembly High