Relief-device screening tools for API-style PSV sizing, required area, and standard orifice selection.
When to use these calculators
Use this section for early relief-valve sizing checks before final verification against project standards and vendor data.
Typical workflow
Define the credible relief case and required mass flow.
Calculate required API 520 gas/vapor relief area.
Select the next standard API 526 orifice and verify assumptions against the final design basis.
Calculators
Relief Valve Sizing (API 520) Calculator — Required PSV orifice area for vapor (critical flow) or liquid service per API 520, with the selected API 526 standard orifice.