PSV Relief Load Summarizer

Aggregates a set of API 521 relief scenarios into (a) a per-PSV governing scenario (largest mass flow) and (b) a per-header total load. Useful for sizing collection headers and flare knockout drums. Required columns: psv_tag, service, header, scenario, mass_flow_lb_hr, mabp_psig.

CSV Input

References: API Std 521 (7th Ed., 2020) Pressure-relieving and Depressuring Systems; API Std 520 Pt I / II Sizing, Selection, and Installation of Pressure-relieving Devices. The ‘governing scenario’ is simply the largest mass flow per PSV — engineer must separately confirm the scenario is a valid simultaneous event for header sizing (see API 521 § 5.3).

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