Engineering · Auxiliary — Pumps
A positive-displacement pump (e.g., gear or screw) must be protected with a relief valve because it:
- ACannot build pressure
- BWill build pressure until something fails if the discharge is closed✓ Correct
- CNeeds priming each start
- DLoses prime at high speed
Explanation
A positive-displacement pump moves a fixed volume per revolution; against a closed discharge it keeps building pressure until a line, casing, or driver fails — so a relief valve is mandatory.
Authority: Auxiliary Machinery (USCG engineering topic)
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