Net Pump Discharge Pressure is defined as what?

• A. The Discharge Pressure
• B. The Intake Pressure
• C. The Sum Of Discharge And Intake Pressures
• D. The Actual Pressure Produced By The Pump; Difference Between The Intake Pressure And The Discharge Pressure

Answer: (D)

Net Pump Discharge Pressure is the pressure increase the pump provides as water moves from the suction side to the discharge side. It’s the actual pressure the pump adds to the water, equal to the difference between the discharge pressure and the intake (suction) pressure. In practice you measure the discharge pressure and the suction pressure and subtract suction from discharge to get this value. This reflects the pump’s head development and is what drives water through the hose, overcoming friction and elevation changes. For example, if the discharge gauge reads 100 psi and the intake gauge reads 60 psi, the net pump discharge pressure is 40 psi. The other options don’t fit because they either ignore the suction pressure, just use the discharge pressure, or wrongly add pressures together instead of finding the pump’s added pressure.