Calculators — Relief & Venting

Six calculators covering the API relief-system family: PSV orifice sizing for gas/liquid/steam (API 520 Part I + API 526 letters), thermal/hydraulic-expansion relief (API 521 §4.4.13), fixed restriction-orifice sizing (ISO 5167-2 / Crane TP-410), atmospheric tank venting (API 2000), and PSV installation checks — inlet ΔP, built-up backpressure, open-discharge reaction force (API 520 Part II). Several modules deliberately reuse each other (thermalRelief imports reliefValve's liquid-sizing + fire-heat functions; psvDatasheet imports both reliefValve and psvLinePressureDrop) rather than re-deriving the same physics twice.