Udemy - Blowdown and Depressurisation - API 521 Fire Case Design

Blowdown & Depressurisation: API 521 Fire Case Design

https://WebToolTip.com

Published 9/2026
Created by ProjectEngPro Engineering and Project Management
MP4 | Video: h264, 1920x1080 | Audio: AAC, 44.1 KHz, 2 Ch
Level: All Levels | Genre: eLearning | Language: English | Duration: 20 Lectures ( 4h 6m ) | Size: 2.2 GB

Set a depressurisation rate, check vessel wall temperature and avoid brittle fracture — fire case, orifice sizing

What you'll learn
⚡ Determine a depressurisation rate and justify it against API 521 guidance and owner criteria
⚡ Calculate fire heat input to a vessel using the API 521 equations and wetted surface determination
⚡ Assess vessel wall temperature response during a fire and predict the time to rupture
⚡ Evaluate rupture risk by comparing wall stress against temperature-dependent yield strength
⚡ Identify low temperature embrittlement risk from Joule-Thomson cooling on depressurisation
⚡ Assess the coldest metal temperature reached and where it occurs in the system
⚡ Size restriction orifices for the required depressurisation rate including choked flow
⚡ Select blowdown valves and specify the fail-open actuation the duty requires
⚡ Calculate the blowdown contribution to flare load and the back pressure it imposes
⚡ Reassess a legacy blowdown system against current guidance and identify the gaps

Requirements
❗ No prior blowdown experience is required — the fire case and cooling mechanisms are built from first principles
❗ Any engineering or technical background is enough to follow the course
❗ Comfortable with basic algebra — heat input and orifice sizing are worked step by step
❗ No software or licence needed to follow the course
❗ Helpful but not essential: familiarity with pressure relief or process safety