A sliding bearing’s lifetime is a complex story, which results from the sum of the many parameters’effect. In our section: Parameters for bearing selection, we discuss the most important.

These are:

Load
Temperature
Operation
Movement
Bearing housing
Bearing play
Friction
Chemicals
Operating environment
Lubrication
Opposing rotational partner

There are many more factors that affect a slide bearing’s lifetime, however, with the help ofthose mentioned above, it is possible to determine approximately how long a slide bearing willfunction as it ought. The reason for using the phrase “as it ought” is that the slide bearing’slifetime is wholly dependent on how much wear or abrasion the design can allow. The slidebearing and its opposing rotational partner function quite simple as a closed tribological system.When the sliding surface of the bearing has worn down to the level that can be allowed, before the clearence is adventured, the bearing is worn out. Below, the wear factor k is shownas a function of some normal lubrication conditions.
The wear factor is dependent on the lubricant condition and the materialcombination. It is normally determined by laboratory testing and is based on Archard’s wear equation.

VS^-1 = K(FH)^-1

Where V is the volume of material worn away, S the total sliding length.F the normal force i.e. the load, and H is the hardness of the worn material.
Below is presented a summary of the factors influencing the rate of wear and in consequence to be considered during design.