This is the most basic and most widely used type of tapered roller bearing. It consists of two main separable parts: the cone (inner ring) assembly and the cup (outer ring). It is typically mounted in opposing pairs on a shaft.
C1 - Dynamic Radial Rating (Two-Row, 1 million revolutions)1
N/A4230 lbf18800 N
C90(2) - Dynamic Radial Rating (Two-Row, 90 million revolutions)2
N/A1100 lbf4880 N
Dimensions
d - Cone Bore
N/A0.3125 in7.938 mm
B - Cone Width
N/A0.4246 in10.785 mm
Abutment and Fillet Dimensions
R - Cone Backface "To Clear" Radius3
N/A0.02 in0.50 mm
da - Cone Frontface Backing Diameter
N/A0.49 in12.5 mm
db - Cone Backface Backing Diameter
N/A0.51 in13 mm
Ab - Cage-Cone Frontface Clearance
N/A0.09 in2.3 mm
Aa - Cage-Cone Backface Clearance
N/A-0.03 in-0.8 mm
a - Effective Center Location4
N/A-0.12 in-3 mm
Basic Load Ratings
C90 - Dynamic Radial Rating (90 million revolutions)5
N/A630 lbf2800 N
C1 - Dynamic Radial Rating (1 million revolutions)6
N/A2430 lbf10800 N
C0 - Static Radial Rating
N/A2070 lbf9230 N
Ca90 - Dynamic Thrust Rating (90 million revolutions)7
N/A437 lbf1940 N
Factors
K - Factor8
N/A1.44
G1 - Heat Generation Factor (Roller-Raceway)
N/A1.7
G2 - Heat Generation Factor (Rib-Roller End)
N/A3.2
Cg - Geometry Factor9
N/A0.0308
1 Based on 1 x 106 revolutions L10 life, for the ISO life calculation method.
2 Based on 90 x 106 revolutions L10 life, for The Timken Company life calculation method. C90 and Ca90 are radial and thrust values for a single-row, C90(2) is the two-row radial value.
3 These maximum fillet radii will be cleared by the bearing corners.
4 Negative value indicates effective center inside cone backface.
5 Based on 90 x 106 revolutions L10 life, for The Timken Company life calculation method. C90 and Ca90 are radial and thrust values.
6 Based on 1 x 106 revolutions L10 life, for the ISO life calculation method.
7 Based on 90 x 106 revolutions L10 life, for The Timken Company life calculation method. C90 and Ca90 are radial and thrust values for a single-row, C90(2) is the two-row radial value.
8 These factors apply for both inch and metric calculations. Consult your Timken representative for instruction on use.
9 Geometry constant for Lubrication Life Adjustment Factor a3l.