LPG Fundamentals and More: A Journey to Expertise

A: −20 °C is the usual minimum design metal temperature boundary for plain A516 without proven impact toughness. Dropping to −35 °C during rapid depressurisation shifts the failure mode from strength‑controlled to toughness‑controlled; corrosion mechanisms don’t act on that time scale.

A: ≈34 kW/m² is the reference external fire heat flux embedded in LPG relief sizing. That heat input vaporises liquid faster than volumetric expansion alone and governs shell integrity under fire exposure.

A: At 30 °C, propane is near 10 bar(a) while n‑butane is around 3 bar(a); blending shifts equilibrium but temperature still drives absolute pressure. The response is verification, not intervention, as long as relief and MAWP margins remain intact.

A: 80–85% is a volumetric limit at a reference temperature, not a raw gauge number. Temperature correction and tank strapping determine whether the apparent conflict is real.