They are considered linear or axial when the moving parts they separate travel along a straight line, such as a drawer opening. Other common applications for ball bearing slides are found in the furniture, electronic and construction sectors.
The rows of ball bearings within linear ball bearings are typically held in place by rods, or shaft assemblies, and the load bearing carriage moves along these rods as the ball bearings rotate or roll. The rolling bearings offer a lower coefficient of friction than if the two flat surfaces were moving across each other, thus allowing for less energy to be used in the moving of a load. Linear ball bearings, or linear rotary bearings, are a popular motion improving choice in many industrial applications as they are typically easy to manufacture and to replace when necessary.
The lifespan of a bearing is based both on the load it carries and its operating speed. The heavier the load and the higher the speed, the more often bearings will need to be replaced in the bearing assembly. Metal fatigue will inevitably occur due to wear and tear and the pressure placed upon the bearings.
Factors that can further affect the lifespan of a bearing include its material properties and any lubrication added to the process. While ball bearing systems tend to be low maintenance options, they may require periodic maintenance to ensure their optimum performance. In applications where debris or particles of elements are produced or present in the environment, these particles can get into the assembly or conveyor and clog the movement of the bearings themselves. Therefore, these precision linear bearings may require frequent cleaning to allow the balls to rotate freely.
Lubrication is also recommended to reduce the wear on the surface of the ball bearings and thus extend their lifespan. Stainless steel is a material commonly used in the construction of ball bearings and linear roller bearings as it is corrosion resistant and highly durable. Aluminum and other metal alloys are also used in the construction of both bearings and the housing unit.
Ball bearing linear slides are most useful in light to moderate load movement and size can be a determining factor in the use of ball bearings as the slide has to fit into the housing or drive system. Linear ball bearings however, can be adapted for use with many custom application requirements.