🔍 Key Concepts

• Centrifugal pump suction piping best practices – how suction side layout affects priming and NPSH (Net Positive Suction Head) • Difference between eccentric and concentric reducers and how an eccentric reducer can create or eliminate an air pocket • Effect of air/vapor pockets at the pump suction on cavitation and loss of suction

💭 Think About

• Look closely at the illustration: where would any trapped air naturally try to rise and collect in this run of pipe? • Ask yourself: should the top of the suction pipe be a straight, continuous line into the pump, or is it acceptable to create a ‘high spot’ or pocket just before the pump? • Which reducer orientation would keep the liquid completely filling the suction line right up to the pump, with no place for air to sit?

✅ Before You Answer

• Verify which answer choice directly addresses avoiding air accumulation/pockets at the highest point of the suction run • Confirm that good practice keeps the suction pipe’s top surface level or sloping continuously toward the pump, without creating a local high point • Eliminate any option that would place the eccentric offset upward, forming a space where air could be trapped before entering the pump