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Smarter Bearing Selection Is Here

The Timken ® Syber ® Bearing System Designer Tool now features Smart Selection, enabling users to find the right bearing faster by filtering options based on target life and key dimensions.

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Analyze Bearing Performance in an Application with Timken ® Syber ® Bearing System Designer

A powerful software tool that combines calculators and configurators to assist you with application design, bearing selection, installation, and troubleshooting. It’s free, easy-to-use, and accessible 24/7.

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Simplified Gear Force Analysis

Alex Waye, Timken Application Engineer, shows you how to instantly compute tangential, radial, and axial forces for better design decisions.

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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 30305M

Cone Part Number

 N/A X30305M

Cup Part Number

 N/A Y30305M

Design Unit

 N/A Metric

Cage Material

 N/A Stamped Steel

Related Assembly Number(s)

 N/A 30305M-90KM1

Dimensions

d - Bore

 N/A 25 mm0.9843 in

D - Cup Outer Diameter

 N/A 62 mm2.4409 in

B - Cone Width

 N/A 17.000 mm0.6693 in

C - Cup Width

 N/A 15.000 mm0.5906 in

T - Bearing Width

 N/A 18.250 mm0.7185 in

Abutment and Fillet Dimensions

R - Cone Backface "To Clear" Radius1 N/A 1.520 mm0.06 in
r - Cup Backface "To Clear" Radius2 N/A 1.52 mm0.06 in

da - Cone Frontface Backing Diameter

 N/A 32.5 mm1.28 in

db - Cone Backface Backing Diameter

 N/A 34.5 mm1.36 in

Da - Cup Frontface Backing Diameter

 N/A 57.66 mm2.27 in

Db - Cup Backface Backing Diameter

 N/A 55.12 mm2.17 in

Ab - Cage-Cone Frontface Clearance

 N/A 3.3 mm0.13 in

Aa - Cage-Cone Backface Clearance

 N/A -0.5 mm-0.02 in
a - Effective Center Location3 N/A -5.1 mm-0.2 in

Basic Load Ratings

C90 - Dynamic Radial Rating (90 million revolutions)4 N/A 13900 N3130 lbf
C1 - Dynamic Radial Rating (1 million revolutions)5 N/A 53800 N12100 lbf

C0 - Static Radial Rating

 N/A 49600 N11200 lbf
Ca90 - Dynamic Thrust Rating (90 million revolutions)6 N/A 7160 N1610 lbf

Factors

K - Factor7 N/A 1.95
e - ISO Factor8 N/A 0.3
Y - ISO Factor9 N/A 2

G1 - Heat Generation Factor (Roller-Raceway)

 N/A 11.8

G2 - Heat Generation Factor (Rib-Roller End)

 N/A 8.5
Cg - Geometry Factor10 N/A 0.0532
  • 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 Negative value indicates effective center inside cone backface.
  • 4 Based on 90 x 106 revolutions L10 life, for The Timken Company life calculation method. C90 and Ca90 are radial and thrust values.
  • 5 Based on 1 x 106 revolutions L10 life, for the ISO life calculation method.
  • 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 Geometry constant for Lubrication Life Adjustment Factor a3l.
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