Which component is described as the hollow inner of the pump housing?

• A. Volute
• B. Impeller
• C. Suction port assembly
• D. Vent valve

Answer: (A)

The hollow inner of the pump housing is the volute. The volute is the stationary chamber that surrounds the impeller and collects the fluid after it's accelerated by the blades, guiding it toward the discharge while gradually increasing the cross-sectional area to convert velocity energy into pressure. This distinguishes it from the impeller, which is the rotating part with blades that increases the fluid’s velocity, and from the suction port assembly (entry path for fluid) and the vent valve (air removal). In short, the volute’s role is to house the fluid within the pump housing and direct it to the discharge while helping convert dynamic energy into pressure.