Pumping Systems & Pump Selection Flashcards

Which pump type is most appropriate for chemigation (injecting fertilizers or pesticides into irrigation water)?

Answer: Positive displacement pump (piston or diaphragm)

Positive displacement pumps deliver a precise, metered volume per stroke regardless of system pressure, making them ideal for accurate chemical injection.

Static suction lift is the vertical distance between the:

Answer: Water surface and the pump centerline when the pump is above the water source

Static suction lift is the vertical elevation the pump must lift water on the inlet side; atmospheric pressure limits this to approximately 25 feet at sea level.

Pump efficiency (Ep) is defined as the ratio of:

Answer: Water horsepower (WHP) to brake horsepower (BHP)

Pump efficiency = WHP / BHP × 100%, where WHP is the hydraulic power actually delivered to the water and BHP is the shaft power input to the pump.

A turbine pump is most commonly used in which irrigation application?

Answer: Deep well and large-volume agricultural pumping

Vertical turbine pumps are engineered for deep well and high-volume agricultural applications where a standard centrifugal pump cannot reach the water source.

What is the significance of the pump curve intersection with the system curve?

Answer: It is the operating point where the pump actually runs in the system

The intersection of the pump curve and system curve defines the actual operating flow rate and head for the installed system.

Wire-to-water efficiency of a pump system measures overall efficiency from:

Answer: Electrical power input at the utility meter to hydraulic power delivered to the water

Wire-to-water efficiency accounts for motor, pump, and any drive system losses—it is the most complete measure of energy performance for an irrigation pump station.