🔍 Key Concepts

• Centrifugal pump internal clearances and how they affect efficiency and pressure • Purpose of wearing rings versus packing and glands • Where most of the high‑pressure/low‑pressure leakage path is inside a centrifugal pump

💭 Think About

• Think about which two parts in a centrifugal pump form the main leakage path between the high‑pressure discharge side and the low‑pressure suction side. • Ask yourself: which clearance, if too large, would let water recirculate inside the pump instead of going out to the system, causing loss of discharge pressure? • Consider which listed components are actually in contact with, or very close to, the high‑velocity flow at the impeller eye and periphery.

✅ Before You Answer

• Identify which option includes impeller plus a part specifically designed to be replaced due to wear from internal leakage. • Confirm which components (lantern rings, packing, glands) are mainly related to shaft sealing to the outside, not internal discharge pressure. • Make sure the parts you select are located at the interface between high‑pressure discharge and low‑pressure suction inside the pump casing.