Wear rings on a pump are intended to wear on which part?

• A. an economically replaceable part
• B. the impeller
• C. the casing
• D. the bearings

Answer: (A)

Wear rings are sacrificial, replaceable interfaces that control the clearance between the impeller and the casing and help limit leakage. They’re designed to wear instead of the more expensive, critical parts of the pump, so when wear occurs you can simply replace the rings to restore performance. The rings are made softer than the adjacent components to ensure wear concentrates on them, protecting the impeller and casing from rapid degradation. If wear happened on the impeller, casing, or bearings, the repair would be far costlier and more involved, whereas replacing the rings keeps maintenance economical.