🔍 Key Concepts

• Centrifugal pump wear points: where metal-to-metal clearance is small and flow is high • Purpose of wearing rings in pumps (protecting major components vs. being sacrificial parts) • How design features affect frequency of major component replacement (impeller, casing)

💭 Think About

• Which option describes a feature that is meant to take the wear instead of the main impeller or casing? • Think about whether tight clearances reduce or increase the chance of rubbing and wear over time. • Ask yourself: does a removable part automatically reduce wear, or just make maintenance easier when wear has already occurred?

✅ Before You Answer

• Identify which component is intended to be sacrificial and easily replaced in many centrifugal pump designs. • Decide which choices mainly affect maintenance access versus actual wear of impeller and casing. • Check which feature is specifically designed to protect the impeller and casing surfaces from erosion and clearance increase.