What type of pump uses a moving piston for fluid movement?

The type of pump that uses a moving piston for fluid movement is the reciprocating pump. This pump operates by utilizing a piston that moves back and forth within a cylinder, creating a change in volume that facilitates the intake and discharge of fluid. As the piston moves forward, it forces the fluid out of the discharge port; conversely, as it moves backward, it draws fluid into the cylinder through an inlet valve.

This mechanism allows for precise control of flow rates and creates high pressures, making reciprocating pumps suitable for applications requiring high pressure and low to moderate flow rates. They are often used for delivering fluids such as water, chemicals, or fuels in various industrial settings.

Other types of pumps listed operate on different principles. Rotary pumps, for example, move fluid by rotating gears or lobes, while centrifugal pumps rely on rotational energy from impellers to impart velocity to the fluid. Diaphragm pumps utilize a flexible diaphragm to displace fluid, rather than a piston moving in a cylinder. Each of these alternative designs has its own specific applications and is chosen based on the requirements of the system being used.