ASME B16.9 Factory-Made Wrought Buttwelding Fittings
ASME B16.9-2018 covers factory-made wrought buttwelding fittings (elbows LR/SR, tees, reducers, caps, returns, crosses, lap-joint stub ends) NPS 1/2–NPS 48 (DN 15–1200), with pressure ratings equated to straight seamless pipe of equivalent material per ASME B31 codes..
Scope
ASME B16.9-2018 covers factory-made wrought buttwelding fittings (elbows LR/SR, tees, reducers, caps, returns, crosses, lap-joint stub ends) NPS 1/2–NPS 48 (DN 15–1200), with pressure ratings equated to straight seamless pipe of equivalent material per ASME B31 codes.
Mechanical & Performance Requirements
Pressure rating is tied to the connecting pipe wall thickness — fittings are rated as seamless pipe of equivalent material; design may use code calculations (B31.3 §304.2/304.3), proof testing per Section 9, or detailed stress analysis.
Dimensional Tolerances
Full tolerance tables (Section 11): center-to-face/center-to-end (e.g. NPS 14–18 LR elbow ±6 mm), OD at weld bevel (+4.8/−0.8 mm for NPS 14–18), wall thickness min = nominal pipe wall, angularity, and welding-end transition envelope per Figure 8-1.
NDE & Hydrostatic Testing
Design proof tests or production hydrostatic validation per Section 9/10; surface examination for seams/laps; marking per Section 4 with material identity (ASTM/ASME grade), size, schedule.
Products We Supply to This Standard
| Applicable products | Link |
|---|---|
| Butt-Weld Fittings | View products → |
| Pipe Elbows | View products → |
| Pipe Tees | View products → |
| Reducers | View products → |
| Pipe Caps | View products → |
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