The purpose of priming a centrifugal pump is to___________________?
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Answer: C. Avoid chances of separation inside the impeller
Explanation
Priming a centrifugal pump fills the internal casing and suction piping with liquid. This process successfully displaces and removes trapped air pockets that cause vapor lock. Removing air ensures smooth impeller operation and prevents flow separation inside the pump channels. Centrifugal pumps rely on centrifugal force imparted by spinning impellers to accelerate liquids. Air has a much lower density than liquids, preventing the impeller from generating adequate pressure head. Loss of prime causes dry running, overheating, and potential mechanical seal damage in pumps.
Water utility operators must verify pump priming procedures before energizing large centrifugal water pumps. Industrial chemical plants install self priming pumps or auxiliary priming systems to prevent operational delays. Proper priming protocols safeguard industrial rotating equipment from catastrophic dry running thermal failures. Option a mentions increasing mass flow rate, but priming is necessary simply to establish any flow. Option b refers to pressure rise development, which is enabled by priming but not the direct mechanical goal. Option d is incorrect because priming specifically addresses internal air removal rather than other outcomes.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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