Menu
Batch CAD Cart (0) ▾
  • Cart is empty
  1. Click Here for Batch Download
Request Information Add to CAD Cart
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.
Unit of Measure

Specifications

Series

 N/A 745

Cone Part Number

 N/A 749-S

Design Units

 N/A Imperial

Cage Type

 N/A Stamped Steel
C1 - Dynamic Radial Rating (Two-Row, 1 million revolutions)1 N/A 147000 lbf656000 N
C90(2) - Dynamic Radial Rating (Two-Row, 90 million revolutions)2 N/A 38200 lbf170000 N

Dimensions

d - Cone Bore

 N/A 3.3475 in85.027 mm

B - Cone Width

 N/A 1.8375 in46.673 mm

Abutment and Fillet Dimensions

R - Cone Backface "To Clear" Radius3 N/A 0.2 in5.1 mm

da - Cone Frontface Backing Diameter

 N/A 3.74 in95 mm

db - Cone Backface Backing Diameter

 N/A 4.09 in104 mm

Ab - Cage-Cone Frontface Clearance

 N/A 0.08 in2 mm

Aa - Cage-Cone Backface Clearance

 N/A 0.05 in1.3 mm
a - Effective Center Location4 N/A -0.47 in-11.9 mm

Basic Load Ratings

C90 - Dynamic Radial Rating (90 million revolutions)5 N/A 21900 lbf97600 N
C1 - Dynamic Radial Rating (1 million revolutions)6 N/A 84700 lbf377000 N

C0 - Static Radial Rating

 N/A 93800 lbf417000 N
Ca90 - Dynamic Thrust Rating (90 million revolutions)7 N/A 12200 lbf54400 N

Factors

K - Factor8 N/A 1.8

G1 - Heat Generation Factor (Roller-Raceway)

 N/A 159.6

G2 - Heat Generation Factor (Rib-Roller End)

 N/A 26.3
Cg - Geometry Factor9 N/A 0.0898
  • 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.
By clicking Submit, you consent to the personal information you provide being used in the manner as described in our Privacy Notice, including access to that information by Timken personnel who may be located outside your home country. In addition, you agree that the CAD drawings are for your personal, one-time use only, and that you will not modify or create any compilation or derivative work using the CAD drawings or distribute or display the CAD drawings on any website or other media.