Which term is a type of pump bearing?

• A. Thrust ball bearing
• B. Single-row stiff ball bearing
• C. Spherical roller bearing
• D. Journal bearing

Answer: (B)

Pump bearings must provide rigid, precise support for the rotor while minimizing friction so the shaft stays aligned during operation. A single-row stiff ball bearing fits this need well: it’s a radial ball bearing designed for high stiffness and smooth rotation, which helps maintain shaft alignment and reduce vibration in pumps. That combination of properties makes it a common choice as a pump bearing.

The other options aren’t as representative of a standard pump bearing in typical designs. A thrust ball bearing handles axial loads more than radial, and many pumps rely on radial support for the main bearing. A journal bearing is a plain bearing that relies on a lubricant film, which is a different category of bearing. A spherical roller bearing can carry heavy radial loads and misalignment but is less commonly used as the typical pump bearing due to size and mounting considerations.