COMPANY HEADER
Print Back
TDI bearings have a one-piece double inner race and two single outer races and are typically supplied complete with an outer race spacer as a pre-set assembly. The bearing can be used at fixed positions on rotation shaft applications. For rotating housing application it can be used to float on the stationary shaft.
Unit of Measure

Specifications

Series

 N/A 78000

Cone Part Number

 N/A 78255D

Cup Part Number

 N/A 78571

Design Unit

 N/A Inch

Cage Material

 N/A Stamped Steel

Dimensions

d - Bore

 N/A 2.5586 in

D - Cup Outer Diameter

 N/A 5.7080 in

B - Double Cone Width

 N/A 2.5980 in

C - Cup Width

 N/A 0.9058 in

T - Bearing Width across Cups

 N/A 2.5616 in

Abutment and Fillet Dimensions

R - Cone Backface "To Clear" Radius1 N/A 0.06 in
r - Cup Backface "To Clear" Radius2 N/A 0.140 in

da - Cone Frontface Backing Diameter

 N/A 3.11 in

Db - Cup Backface Backing Diameter

 N/A 4.65 in

Ab - Cage-Cone Frontface Clearance

 N/A 0.08 in

Basic Load Ratings

C90 - Dynamic Radial Rating (One-Row, 90 million revolutions)3 N/A 9970 lbf44300 N
C1 - Dynamic Radial Rating (Two-Row, 1 million revolutions)4 N/A 66900 lbf298000 N
C90(2) - Dynamic Radial Rating (Two-Row, 90 million revolutions)5 N/A 17400 lbf77200 N
Ca90 - Dynamic Thrust Rating (90 million revolutions)6 N/A 14800 lbf65700 N

Factors

K - Factor7 N/A 0.67
e - ISO Factor8 N/A 0.87
Y1 - ISO Factor9 N/A 0.78
Y2 - ISO Factor10 N/A 1.16
Cg - Geometry Factor11 N/A 0.0884

Spacer

Note

 N/A Spacer shows standard nominal .01 radii, actual bearing may vary
  • 1 These maximum fillet radii will be cleared by the bearing corners.
  • 2 These maximum fillet radii will be cleared by the bearing corners.
  • 3 Based on 90 x 106 revolutions L10 life, for The Timken Company life calculation method. C90 and Ca90 are radial and thrust values.
  • 4 Based on 1 x 106 revolutions L10 life, for the ISO life calculation method.
  • 5 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.
  • 6 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.
  • 7 These factors apply for both inch and metric calculations. Consult your Timken representative for instruction on use.
  • 8 These factors apply for both inch and metric calculations. Consult your Timken representative for instruction on use.
  • 9 These factors apply for both inch and metric calculations. Consult your Timken representative for instruction on use.
  • 10 These factors apply for both inch and metric calculations. Consult your Timken representative for instruction on use.
  • 11 Geometry constant for Lubrication Life Adjustment Factor a3l.