Linear bearings undergo reciprocating rather than rotary motion so that accelerations are much higher than typically experienced by rotary bearings. Since linear bearings have become important primarily as a result of robotic automation, one must often refer to manufacturer's literature for load/life formulas.
What follows is one way to calculate the life of a linear slide bearing. The symbol L is used to represent the rated life. It is defined as the length of travel endured by the slide under a specified condition. In reality, slide life varies from one slide to another, so that a rating referred to as L10 is typically used in industry. The L10 rating is defined as the length of travel that 90% of all slides (of the same model) will complete before the first sign of failure.
The following factors are used in the calculation of load/life predictions:
1. Factor for Speed


where 
V = 
the speed of the relative carriage/base movement in inches/minute (use the peak speed value). 

m = 
3 for ball slides, 3.3 for roller slides. 
NOTE: When the speed is less than 30 inches/minute, fs = 1. 
