Marine Boiler - Operational Pressure Check

Operating pressure must remain below design pressure with reasonable margin. Safety valve set typically at design pressure (some class rules allow up to 1.05 x design). Hydrostatic test at 1.5 x design at construction. Operating beyond design pressure is forbidden under classification society rules and indicates need for immediate shutdown and investigation. Margin below 5 percent of design typically indicates unusual operating condition; margin below 0 indicates over-pressure event.

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