What is the main function of a bearing?

The primary function of a bearing is to reduce friction, which allows rotating components to move smoothly relative to each other. Bearings achieve this by creating a separation between moving surfaces, thus minimizing the direct contact that would otherwise lead to wear and heat generation. This reduction in friction improves efficiency, prolongs the lifespan of moving parts, and ensures smoother operation.

While keeping the position of the shaft center is a secondary benefit of bearings, as they help to align and stabilize rotating shafts, the fundamental purpose is primarily focused on reducing friction. This is pivotal in many applications, especially in machinery such as forklifts, where smooth operation is critical for performance and safety. Other options like providing insulation or enhancing torque capacity are not primary functions of bearings but rather associated with specific scenarios or components in mechanical systems.