What could cause low discharge pressure in a centrifugal pump?

Low discharge pressure in a centrifugal pump can be caused by a clogged or worn impeller. The impeller is a critical component in a centrifugal pump that is responsible for converting mechanical energy into hydraulic energy to move the fluid. When the impeller becomes clogged, the flow of the fluid is restricted, which can lead to a significant drop in discharge pressure. If the impeller is worn, it may not impart sufficient energy to the fluid, again resulting in lower pressure at the discharge.

Both clogging and wear can impede the efficient operation of the pump, reducing its ability to effectively move fluid from the suction side to the discharge side. This can manifest as an overall decrease in discharge pressure, affecting the pump's performance and the system's hydraulic balance.

Other factors, such as high viscosity fluids, insufficient power supply, or excessive suction lift, can influence pump performance as well, but they do not directly impact the discharge pressure in the same manner as issues with the impeller do. High viscosity can lead to increased friction losses, insufficient power may cause the pump to operate below its design capacity, and excessive suction lift can reduce the net positive suction head available, but these conditions do not inherently cause low discharge pressure in the same way that impeller issues do.