Tolerances for Mounted Ball Bearing Units from ABT Bearings

Mounted bearing units for shaft sizes less than 2" have clearance fit-ups. Units for 2 and greater shaft sizes have light interference fit-ups.

Pillow block tolerance base to shaft is:

Bore Tolerance
1/2 to 1-15/16 in∓ .006 in
2 to 3-1/2 in∓ .008 in

Inner and outer ring tolerances are shown in the tables below.

Inner Ring Tolerance (Metric and Inch)

MM INCHES
Bore Diameter (d) Tolerance Bore Diameter (d) Tolerance
Over Inc. + - Over Inc. + -
10180.01500.3940.7090.00060
18300.01800.7091.1810.00070
30500.02101.1811.9690.00080
50800.02401.9693.1500.00090
801200.02803.1504.7240.00110
1201800.03304.7247.0870.00130

Outer Ring Tolerance (Metric and Inch)

MM INCHES
OD (D) Tolerance OD (D) Tolerance
Over Inc. + - Over Inc. + -
61800.0080.2360.70900.0003
183000.0090.7091.18100.00035
305000.0111.1811.96800.00045
508000.0131.9683.15000.0005
8012000.0153.1504.72400.0006
12015000.0184.7245.90500.0007