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Safety Valve Area (ASME I)

Approximate required safety-valve throat area from steam capacity and set pressure using the ASME Section I formula.

SteamBoilerSafety
Required throat area
3,206mm²

Formula, assumptions, and limits

ASME Section I steam discharge formula (W in lb/h, P in psia, A in in²). We convert units inline so inputs can be kg/h and bar. Always size to the ASME-certified flow rate on the valve nameplate, not the calculated throat area alone.

Symbol legend

SymbolMeaningUnitSource
Steam capacitykg/hboiler rating
Set pressure absolutebarboiler design
Valve coefficient of discharge - valve data sheet
Back-pressure correction - ASME I
Superheat correction - ASME I
Required throat areamm²result