Issuing body
ASME
Latest edition
2020 Edition
Region
USA, Global
Equipment items
1
Scope
Series A (formerly MSS SP-44) and Series B (formerly API 605) large-diameter flanges.
Key requirements (6)
- Large-diameter steel flanges — NPS 26 through 60.
- Series A (MSS SP-44 lineage, heavier) or Series B (API 605, lighter).
- Pressure classes 150, 300, 400, 600, 900.
- Used for pipelines, large vessels, atmospheric tanks.
- Hydrotest: per pressure class rating chart.
- Bolting per ASTM A193 / A194; Series A typically larger studs than Series B.
Related standards (2)
Applied to 1 equipment item
Piping & Fittings