OIT Pumping Systems and Hydraulics Flashcards

What is the purpose of a wet well in a pump station?

Answer: To collect and temporarily store wastewater or water before it is pumped out

A wet well is a below-grade chamber that collects influent flow and provides storage volume to allow pumps to cycle on and off efficiently.

What does the term 'priming' mean in relation to a centrifugal pump?

Answer: Filling the pump casing and suction line with liquid to remove air before starting

Priming is the process of filling the pump casing and suction piping with liquid to remove air so the pump can develop suction and move fluid.

What is static head in a pumping system?

Answer: The vertical elevation difference between the water source and the discharge point

Static head is the vertical height difference (elevation) between the suction water surface and the discharge point, independent of flow.

When two identical pumps are operated in parallel, what happens to the system flow rate compared to a single pump?

Answer: Flow rate increases but less than doubles due to increased system friction

Parallel pumps increase flow, but the combined flow is less than double because increased flow raises friction losses in the system, shifting to a higher-head operating point.

What is the primary indicator that a centrifugal pump's mechanical seal is failing?

Answer: Visible water leaking around the pump shaft

A failing mechanical seal allows water to leak around the pump shaft, which is the most visible and common sign of seal failure.

What is the purpose of a surge tank or hydropneumatic tank in a water distribution system?

Answer: To absorb pressure fluctuations and maintain consistent system pressure

A hydropneumatic (pressure) tank uses compressed air to absorb pressure surges and maintain relatively constant system pressure between pump cycles.