What component of a centrifugal pump is installed to hold the priming?

The foot valve is crucial in maintaining priming for a centrifugal pump. It is specially designed to prevent the backflow of fluid, ensuring that the pump retains its prime after the initial start-up. The foot valve is typically placed at the inlet of the pump, submerged in the water source and maintains a column of fluid within the suction line. This design allows for efficient operation as it prevents air from entering the pump, which is essential for centrifugal pumps to function properly, as they rely on fluid movement to create suction.

Other components, while important in different capacities, do not serve the same function as the foot valve in this context. For instance, a user valve typically regulates flow or pressure within a system, but it does not prevent backflow in the same manner. A pressure valve controls the pressure within the system but is not used specifically to maintain priming. A check valve prevents reverse flow in a pipe system but is not usually employed at the pump intake to maintain a prime like the foot valve does. Hence, the foot valve is the component that directly contributes to holding the priming in a centrifugal pump system.