Tankerman · Cargo — Temperature / Pour Point
The pour point of a heavy cargo is important because below it the cargo:
- ABecomes more volatile and explosive
- BStops flowing, so heating coils must keep it above the pour point for pumping and stripping✓ Correct
- CIncreases in API gravity
- DTurns to gas
Explanation
The pour point is the lowest temperature at which an oil will still flow. Below it the cargo congeals and cannot be pumped. Heavy/waxy cargoes are carried with heating coils energized to keep the cargo above its pour point (with margin) for loading, discharge, and stripping.
Authority: ASTM D97; cargo handling references
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