Which factor primarily influences the selection between plain bearings and rolling-element bearings?

Which factor primarily influences the selection between plain bearings and rolling-element bearings?

• A. Load type and speed
• B. Color code
• C. Ambient lighting
• D. Manufacturer country

Answer: (A)

Choosing bearings is driven by how the load is applied and how fast the shaft turns. Plain bearings work well when the load is heavy and the speed is relatively low: they can carry large forces, tolerate some misalignment, and are often simpler and cheaper, relying on a lubricant film to support the load. Rolling-element bearings, on the other hand, are designed to minimize friction and provide high stiffness and precision at higher speeds, making them ideal for fast-running shafts and more demanding accuracy or response requirements. These conditions—load type and speed—control friction, heat, lubrication needs, and bearing life, which is why they primarily determine whether a plain bearing or a rolling-element bearing is chosen. Other factors like color, lighting, or country of manufacture don’t affect the bearing’s mechanical suitability.

Choosing bearings is driven by how the load is applied and how fast the shaft turns. Plain bearings work well when the load is heavy and the speed is relatively low: they can carry large forces, tolerate some misalignment, and are often simpler and cheaper, relying on a lubricant film to support the load. Rolling-element bearings, on the other hand, are designed to minimize friction and provide high stiffness and precision at higher speeds, making them ideal for fast-running shafts and more demanding accuracy or response requirements. These conditions—load type and speed—control friction, heat, lubrication needs, and bearing life, which is why they primarily determine whether a plain bearing or a rolling-element bearing is chosen. Other factors like color, lighting, or country of manufacture don’t affect the bearing’s mechanical suitability.