ASME B16.5 Pipe Flanges & Flanged Fittings
ASME B16.5-2017 covers flanges and flanged fittings NPS 1/2–NPS 24 (DN 15–600) in Classes 150–2500: pressure–temperature ratings, materials, dimensions, gasket/bolt facing, marking, and testing..
Scope
ASME B16.5-2017 covers flanges and flanged fittings NPS 1/2–NPS 24 (DN 15–600) in Classes 150–2500: pressure–temperature ratings, materials, dimensions, gasket/bolt facing, marking, and testing.
Mechanical & Performance Requirements
Pressure–temperature rating tables per material group (Groups 1.1–3.18) — e.g. Group 1.3 (A105-type carbon steel), Class 150 rated 19.6 bar at 38 °C down to 1.4 bar at 538 °C; ratings scale by class (300 = 2× class 150 through class 600 region).
Dimensional Tolerances
Facing dimensions (raised face height/diameter), bolt circle and bolt-hole alignment (bolts pass freely), flange thickness min per class tables, bore diameter tolerances, and spot-facing squareness limits.
NDE & Hydrostatic Testing
Quality system requirements (Appendix B); material certificates (EN 10204/ASTM) required; hydrostatic shell testing not mandated at flange level — verification through material certification and dimensional gauging.
Products We Supply to This Standard
| Applicable products | Link |
|---|---|
| Forged Steel Flanges | View products → |
| Butt-Weld Fittings | View products → |
Explore the Full Standard Family
See all standards in this family on our ASME Standards overview page →