Understanding Pump Pressure and Discharge Quantity in Centrifugal Pumps

At a pumping station equipped with a centrifugal pump, several factors can cause the discharge pressure to suddenly increase and the discharge quantity to suddenly decrease. These factors include:

1. Increase in pump speed: If the pump speed is suddenly increased, it can lead to a higher discharge pressure and lower discharge quantity due to the pump forcing more water out at a faster rate.
2. Decrease in pump speed: On the contrary, a sudden decrease in pump speed can result in lower discharge pressure and higher discharge quantity as the pump is not pushing water out as forcefully.
3. Increase in pump impeller diameter: A larger impeller diameter can also lead to a sudden increase in discharge pressure and a decrease in discharge quantity as the pump can move more water with each rotation.
4. Decrease in pump impeller diameter: Conversely, a smaller impeller diameter can cause a sudden decrease in discharge pressure and an increase in discharge quantity as the pump moves less water with each rotation.

These variations in pump speed and impeller diameter directly impact the pump's ability to generate pressure and move fluid, resulting in changes in discharge pressure and quantity.