Final answer:
To prime a centrifugal pump, you should close the discharge valve, open the suction valve, and open the air vents. This sequence allows the pump to be filled with liquid, avoiding dry running which can damage the pump.
Step-by-step explanation:
The correct sequence to prime a centrifugal pump is to:
- Close the discharge valve
- Open the suction valve
- Open the air vents
This process ensures that air from the suction side and pump casing is removed, allowing the pump to fill with the fluid that it will be moving. It's essential for maintaining the pump's efficiency and preventing damage caused by running the pump dry. Once the pump is fully primed with liquid, the air vents can be closed, and the pump is ready for operation, with the discharge valve being gradually opened to avoid sudden pressure changes that could cause damage or performance issues.