What component collects the water and confines it in order to convert the velocity to pressure?

The pump casing is the component that plays a critical role in the operation of a pump by collecting the water and confining it, which allows for the conversion of velocity into pressure. When water is drawn into the pump via the inlet, the casing surrounds the impeller. As the impeller spins, it accelerates the water, increasing its velocity. The design of the pump casing is such that it narrows down in certain areas, which results in the conversion of that velocity to pressure. This increased pressure is what enables the water to be pushed effectively through the discharge line.

In contrast, the impeller is essential for increasing the velocity of the water but does not confine the water in the same way the casing does. The throttle valve is used to control the flow rate and pressure in the system but does not play a role in the initial collection or confinement of water. The discharge hose is responsible for channeling the water away from the pump but does not contribute to the conversion of velocity to pressure within the pump itself. Therefore, the pump casing is crucial for performing this transformation of velocity into pressure effectively.