🔍 Key Concepts

• Centrifugal pump internal parts and their functions (especially the purpose of each 'ring') • How sealing water or seal flushing is supplied from the discharge side of a pump • Difference between a wearing ring and a ring that forms part of the stuffing box/packing area

💭 Think About

• Think about which part of the pump actually needs a small, controlled flow of liquid to cool, lubricate, and seal around the shaft. • Consider where leaks along the shaft are controlled—what component sits in or near the stuffing box or mechanical seal area to distribute sealing water? • Eliminate any rings whose main job is to reduce internal leakage or sling water away, rather than to receive sealing liquid from the discharge.

✅ Before You Answer

• Verify which component is specifically located in the stuffing box / packing area and is designed with holes or passages for sealing water. • Confirm which ring’s primary purpose is to reduce wear and internal recirculation between impeller and casing—this one is not the target of the sealing line. • Make sure the choice you pick is the one whose function is tied to sealing, cooling, and lubricating the shaft/packing, not just mechanical connection or protection.