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Basic Dimensions

The dimensions and reference codes used by NHBB are illustrated and defined here. These dimensions establish bearing size and other parameters that can help you choose the ball bearing best suited to your application.



d inside diameter or bore
D outside diameter (OD)
B overall bearing width
Bi inner ring width
Bo outer ring width
Df flange outer diameter
Bf flange width
Li inner ring land diameter
Lo outer ring land diameter
r maximum shaft or housing fillet radius bearing corners will clear
Z number of balls per row
Db nominal diameter of balls
Nmax maximum speed (rpm)
fn cage and lubricant factor