Plain vs. Rolling Element Bearings: Choosing the Right Bearing for Your Application

Plain bearings, also known as sleeve, plane, journal or babbitt bearings, are engineered for a wide array of sliding or oscillating applications—including door hinges, automotive ball joints, and tractor‑trailers’ fifth wheels. When full rotation is required, a plain bearing transforms into a sleeve that surrounds the shaft, offering smooth motion without the need for a sealed housing.

• High startup torque typically disqualifies plain bearings for equipment that frequently starts and stops.
• Maintaining a full fluid film demands up to three times the energy of a comparable rolling element bearing, even after startup losses are excluded.
• Grease‑lubricated journal bearings often struggle to sustain a thick oil film without constant replenishment.
• Vertical or thrust‑loaded configurations require specialized Kingsbury or Mitchell designs, which can drive up cost. Most rolling element bearings come in standard sizes, so switching to a rolling bearing may be all that’s needed to handle thrust.
• Plain bearings are usually optimized for a single speed, whereas rolling element bearings tolerate a broader speed range—ideal for variable‑speed drives.

In power‑generation or heavy‑load scenarios where high power density can permanently deform a rolling element raceway, plain bearings may be the safer choice. The API 610 Standard provides detailed guidance on selecting plain versus rolling element bearings for industrial machinery.