API 520
3 in-depth engineering guides on API 520 — specification, selection, testing and procurement.
Everything on API 520
Vajra's engineering team has published 3 technical guides covering API 520 for industrial valve selection, specification, testing and procurement. Browse the full set below.
API 526 Safety Relief Valve Sizing Guide - Orifice Letters, Set Pressures & Back Pressure
API 526 establishes the purchasing standard for flanged spring-loaded safety relief valves used in refinery and chemical plant service - defining orifice letter designations, face-to-face dimensions, flange ratings, and inspection requirements. This guide explains the full API 526 framework alongside API 520 sizing principles for engineers specifying pressure relief devices.
Safety Relief Valve Sizing - API 526 Orifice Areas, Back Pressure, and Set Pressure
A safety relief valve (SRV / PSV) is the last line of defence in a pressure system - it must open at the correct pressure and pass sufficient flow to prevent vessel rupture. API 520 (sizing) and API 526 (dimensional standards) define the engineering framework. This guide explains how to select the orifice size, set pressure, back pressure correction, and trim material for your service.
Pressure Relief Valve Sizing and Selection: API 520 & API 521 Guide
Pressure relief valves (PRVs) are the last line of defence against vessel overpressure. Correct sizing per API 520 Part I and API 521 is critical for plant safety, regulatory compliance, and avoiding costly undersizing or oversizing errors.
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