What type of bearing is typically more prone to failure due to poor lubrication?

• A. Journal bearing
• B. Friction bearing
• C. Magnetic bearing
• D. Active bearing

Answer: (B)

Friction bearings are especially susceptible to failure due to inadequate lubrication because they rely on a direct contact between the bearing surfaces for load support. This type of bearing typically operates on a sliding mechanism, where two surfaces move against each other. When lubrication is insufficient, the sliding surfaces experience increased friction and heat, which can lead to wear and eventually catastrophic failure.

Without proper lubrication, friction bearings can generate excessive heat, leading to thermal expansion and further degradation of the bearing material. Over time, this can cause scoring or galling of the surfaces, ultimately resulting in operational failure.

In contrast, journal bearings, magnetic bearings, and active bearings function under different principles or with additional design features that mitigate the risks associated with inadequate lubrication. For example, journal bearings generally operate with a lubricant film separating the surfaces, which helps reduce wear. Magnetic and active bearings often utilize advanced technologies that reduce metal-to-metal contact, thus decreasing the risk of failure from lubrication issues.