A positive-displacement pump that uses pistons to move fluid is called which?

A positive-displacement pump that uses pistons to move fluid is called which?

• A. Air-lift pumps
• B. Centrifugal pumps
• C. Piston pumps
• D. Pneumatic ejector

Answer: (C)

A piston pump is a positive-displacement pump that uses a piston moving inside a cylinder to trap and push a fixed amount of fluid with each stroke. On the suction stroke, fluid is drawn into the chamber; on the discharge stroke, that exact volume is forced out, giving a predictable flow and the ability to generate higher pressures. This contrasts with other pump types: air-lift pumps rely on compressed air to lift liquid, centrifugal pumps use an impeller to add velocity and depend on head for flow, and pneumatic ejectors use a jet of compressed air to entrain liquid rather than displacing a fixed volume with a piston.

A piston pump is a positive-displacement pump that uses a piston moving inside a cylinder to trap and push a fixed amount of fluid with each stroke. On the suction stroke, fluid is drawn into the chamber; on the discharge stroke, that exact volume is forced out, giving a predictable flow and the ability to generate higher pressures. This contrasts with other pump types: air-lift pumps rely on compressed air to lift liquid, centrifugal pumps use an impeller to add velocity and depend on head for flow, and pneumatic ejectors use a jet of compressed air to entrain liquid rather than displacing a fixed volume with a piston.