What is the purpose of an anti-friction bearing?

What is the purpose of an anti-friction bearing?

• A. To increase friction between rotating parts.
• B. To reduce friction between rotating parts.
• C. To seal lubrication.
• D. To transmit torque as a coupling.

Answer: (B)

Reducing friction between rotating parts is the main job of an anti-friction bearing. It does this by using rolling elements—balls or rollers—so contact between moving surfaces becomes rolling rather than sliding. Rolling contact lowers resistance, which cuts heat, wear, and energy loss, and allows shafts to turn smoothly at higher speeds and with greater life. Proper lubrication and precise clearances further minimize friction and wear. It’s not meant to increase friction, which would just wear components faster. Sealing lubrication is a helpful feature in many bearings to keep lubricant in and contaminants out, but it isn’t the primary purpose. And transmitting torque as a coupling isn’t the bearing’s main function either; while bearings can support torque transmission to a degree, couplings and similar devices are designed specifically to transfer torque between shafts.

Reducing friction between rotating parts is the main job of an anti-friction bearing. It does this by using rolling elements—balls or rollers—so contact between moving surfaces becomes rolling rather than sliding. Rolling contact lowers resistance, which cuts heat, wear, and energy loss, and allows shafts to turn smoothly at higher speeds and with greater life. Proper lubrication and precise clearances further minimize friction and wear.

It’s not meant to increase friction, which would just wear components faster. Sealing lubrication is a helpful feature in many bearings to keep lubricant in and contaminants out, but it isn’t the primary purpose. And transmitting torque as a coupling isn’t the bearing’s main function either; while bearings can support torque transmission to a degree, couplings and similar devices are designed specifically to transfer torque between shafts.