ASME BPVC Sec I

Key requirements (8)

• Power boiler construction (steam generator) — section governs design, materials, fabrication.
• Maximum allowable working pressure (MAWP) calculated per Section I formulas (PG-27 for tubes, PG-29 for shells).
• Joint efficiency E: 1.0 (full RT), 0.85 (spot), 0.70 (no RT) for longitudinal seams.
• Hydrostatic test: 1.5 × MAWP held minimum 30 minutes.
• Mandatory PWHT and impact testing thresholds — stricter than VIII.
• Watertube boiler MAWP often 100–200+ barg for utility; firetube to ~30 barg.
• Material: SA-516, SA-285, SA-106, SA-335 (P11/P22/P91), etc.
• Quality system / authorized inspection mandatory.