🔍 Key Concepts

• centrifugal pump operating characteristics when discharge flow is blocked • difference between pump overheating vs. motor overheating • what happens to energy added by the impeller when liquid cannot flow out

💭 Think About

• Think about where the liquid goes inside a centrifugal pump when the discharge valve is fully closed. Is there any flow path out of the casing? • Consider what happens to the energy the impeller is putting into the liquid if the liquid cannot move away. How does this affect temperature and mechanical parts? • Ask yourself which component is directly acting on the liquid (pump or motor) and which one would first feel the effect of zero-flow, high-friction circulation inside the casing.

✅ Before You Answer

• Verify what the term dead‑heading a centrifugal pump means in terms of flow and heat build‑up. • Check whether a centrifugal pump at zero flow produces high pressure with little motor load or high flow with high motor load. • Consider whether a relief valve automatically cycles in this situation on all centrifugal pumps, or whether overheating of a specific part is the more predictable outcome.