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SarkariResultOutBMS · 2024

Previous Year Question

A long-life of pump is ensured by
  1. pumping ‘neutral liquids’ at high temperatures.
  2. adding abrasive particles in the pumped fluid.
  3. continuous operation at or near the maximum efficiency capacity of the pump.
  4. keeping the Net Positive Suction Head (NPSH) lower than required NPSH.

Correct answer: C

Explanation

A centrifugal pump experiences minimum hydraulic imbalance, vibration and recirculation when operated near its best-efficiency point (BEP). Continuous operation close to the maximum-efficiency capacity therefore promotes long pump life, making option C correct.

Formula

Operate near BEP for minimum hydraulic losses and vibration

Step-by-step solution

Pump Life and BEP explanatory diagram

Correct Answer

C — continuous operation at or near the maximum efficiency capacity of the pump.

Concept and Reasoning

A centrifugal pump experiences minimum hydraulic imbalance, vibration and recirculation when operated near its best-efficiency point (BEP). Continuous operation close to the maximum-efficiency capacity therefore promotes long pump life, making option C correct.

Calculation / Key Relation

Operate near BEP for minimum hydraulic losses and vibration

Exam Takeaway

BEP is the pump’s preferred continuous operating region.

Common Mistake

Operating with inadequate NPSH promotes cavitation and shortens pump life.

Common mistake

Operating with inadequate NPSH promotes cavitation and shortens pump life.

Exam tip

BEP is the pump’s preferred continuous operating region.

Quick method

BEP is the pump’s preferred continuous operating region.