Engineering · Auxiliary — Pumps
Net positive suction head (NPSH) available must always be:
- ALess than the NPSH required by the pump
- BGreater than the NPSH required by the pump to avoid cavitation✓ Correct
- CEqual to the discharge head
- DZero at the pump suction
Explanation
NPSH available (the suction-side energy above vapor pressure) must exceed NPSH required by the pump; otherwise the liquid flashes to vapor at the impeller and the pump cavitates.
Authority: Auxiliary Machinery (USCG engineering topic)
Practice the full Engineering bank
Free spaced-repetition quizzing across 2190 USCG exam questions — it schedules your reviews so the ones you miss come back until they stick.
Related Engineering questions
- Auxiliary — Pumps
A centrifugal pump generally must be primed before starting because it:
- Auxiliary — Pumps
A positive-displacement pump must be fitted with a relief valve because:
- Auxiliary — Pumps
Cavitation in a centrifugal pump occurs when:
- Auxiliary — Pumps
A centrifugal pump should normally be primed before starting because it:
- Auxiliary — Pumps
Net positive suction head (NPSH) available to a centrifugal pump must remain:
- Auxiliary — Pumps
A positive-displacement pump (e.g., gear or screw) must be protected with a relief valve because it: