Which type of pump generally has a greater capacity?

Which type of pump generally has a greater capacity?

• A. Rotary pump
• B. Reciprocating pump
• C. Centrifugal pump
• D. Diaphragm pump

Answer: (C)

Capacity means how much fluid the pump can move per unit time (flow rate). Centrifugal pumps generally provide higher flow because they accelerate fluid with a rotating impeller and then discharge it through a volute, giving a steady, continuous stream. There’s no fixed volume per stroke to limit the flow; increasing the impeller size or the rotational speed raises the flow substantially, up to mechanical limits. In contrast, the other common pump types move a specific amount of fluid with each cycle or revolution (positive-displacement). Rotary pumps have a set displacement per revolution, reciprocating pumps push a fixed volume with each stroke, and diaphragm pumps also displace a defined volume each cycle, which limits their maximum flow compared to a centrifugal pump. For large capacity, centrifugal pumps are typically the better choice.

Capacity means how much fluid the pump can move per unit time (flow rate). Centrifugal pumps generally provide higher flow because they accelerate fluid with a rotating impeller and then discharge it through a volute, giving a steady, continuous stream. There’s no fixed volume per stroke to limit the flow; increasing the impeller size or the rotational speed raises the flow substantially, up to mechanical limits. In contrast, the other common pump types move a specific amount of fluid with each cycle or revolution (positive-displacement). Rotary pumps have a set displacement per revolution, reciprocating pumps push a fixed volume with each stroke, and diaphragm pumps also displace a defined volume each cycle, which limits their maximum flow compared to a centrifugal pump. For large capacity, centrifugal pumps are typically the better choice.