Weld Neck Flange Datasheets
The weld neck flange, abbreviated as WNF, is a flange type that is usually used with pipes, as opposed to pressure vessels. The design of the flange allows for a full penetration weld at its base where it connects to the pipe. This weld can be X-ray inspected for quality control.
Weld Neck Flange Standards
ASME Standards
- ASME B16.5 - Pipe Flanges and Flanged Fittings: NPS 1/2 through NPS 24 Metric/Inch Standard
- ASME B16.36 - Orifice Flanges
- ASME B16.47 - Large Diameter Steel Flanges: NPS 26 Through NPS 60 Metric/Inch Standard
- Series A / MSS SP-44
- For general use
- Bolt circle diameter is larger than Series B
- NOT interchangeable
- Series B / API Std 605 (cancelled)
- For compact use
- Bolt circle diameter is smaller than Series A
- NOT interchangeable
- Series A / MSS SP-44
Weld Neck Flange Sizes - 1/2" through 24"
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Weld Neck Flange Sizes 26" through 60"
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Weld Neck Flange - Industry Standard
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Weld Neck Flange Related Articles
- See bolt circle
- See bolt tightening procedure
- See flange facing, ASME B16.5
- See flange safety spray shield
- See flange
- See flange stamping
- See gasket
- See general flange standards
- See isolation gasket
- See raised face smooth finish
- See spiral wound gasket
- See weld neck flange