Which type of pump features a volute type casing?

A centrifugal pump features a volute type casing, making it the correct answer to this question. In a centrifugal pump, the volute casing is designed to convert the kinetic energy generated by the rotating impeller into pressure energy. The volute shape gradually expands in cross-section to direct the flow of fluid from the impeller out into the discharge pipe, efficiently guiding the fluid while minimizing turbulence and losses.

This design is crucial for the efficient operation of centrifugal pumps, as it helps manage the flow of fluids, allowing for high flow rates and the capability to handle liquids under varying pressures effectively. The volute casing design is particularly beneficial in applications where there is a need to move large volumes of liquid, making centrifugal pumps widely used in sewage treatment and various industrial applications.

Other pump types, such as gear pumps, plunger pumps, and ejector pumps, utilize different principles and constructions. Gear pumps operate using interlocking gears to move fluid, plunger pumps use a reciprocating motion to create pressure, and ejector pumps rely on a jet of fluid to create suction. None of these utilize the volute casing design that characterizes centrifugal pumps.