This reference page provides the dimensional and identification data for a Weld Neck Flange 14 Inch Class 900, including its outside diameter, thickness, hub dimensions, bolt arrangement, stud size, hole diameter, and listed weight. Use the source values for drafting and coordination, then verify the final selection against the project specification and applicable design requirements.
The flange’s tapered hub and direct pipe-weld connection are important when reviewing stress transfer, fabrication details, and alignment. For related design work, connect this reference with your internal resources on pipe schedules, flange facing types, stud bolts, and piping CAD details.
Weld Neck Flange 14″ Class 900
Weld Neck Flange 14″ Class 900 is widely used in piping systems that require strong, leak-resistant flange connections under high-pressure service. It features a long tapered hub that provides excellent stress distribution and is commonly applied in process piping, utility lines, refineries, power plants, and industrial systems where welding strength and reliability are essential.
This dimension data is based on ANSI / ASME B16.5-2020.
Weld Neck Flange 14″ Class 900 Dimensions
- Reference Standard: ANSI / ASME B16.5
- Nominal Pipe Size (NPS):14″
- DN Size: DN350
- Outside Diameter:641mm
- Flange Thickness:85.9mm
- Hub Diameter:451mm
- Bore Diameter: varies depending on pipe schedule and pipe wall thickness
- Raised Face Diameter:412.8mm
- Weight: 237kg
- Number of Bolts:20
- Stud Bolt Size: 1 1/2″ UNC (or M39) x 275 Long
- Hole Diameter: 1 5/8″ (41.275mm)
What Is a Weld Neck Flange?
A weld neck flange is a type of pipe flange designed with a long tapered hub that is welded directly to the pipe. This design helps reduce stress concentration at the flange base and provides better strength under pressure, temperature fluctuation, and cyclic loading.
Common Applications
Weld Neck Flange 14″ Class 900 is commonly used for:
- Process piping systems
- Oil and gas lines
- Refinery and petrochemical piping
- Very high-pressure service
- Pressure piping connections
- Industrial fabrication and maintenance work
CAD Drawing Download
This page includes the CAD drawing file for Weld Neck Flange 14″ Class 900, which can be used for drafting, detailing, piping layout coordination, and fabrication reference.
Available Weld Neck Flange Class 900 Sizes
This size is part of the Weld Neck Flange Class 900 series. Check other sizes in the same category to find matching dimension data and CAD files for your project.
Notes
Before fabrication or installation, always confirm the latest project requirements, flange material specification, pipe schedule, bore size, gasket type, bolt length, and applicable pressure-temperature rating.
How to Use This Flange Reference
The dimension list should be read together with the bore note. The outside diameter, flange thickness, hub diameter, raised face diameter, bolt count, and bolt-hole information describe the flange geometry, while the bore must be matched to the selected pipe schedule and wall thickness. A flange can therefore require a bore check even when the nominal pipe size is already established.
Key Drafting and Fabrication Checks
- Confirm that the flange face, bolt-hole pattern, and mating component are coordinated before producing fabrication drawings.
- Check the pipe outside diameter and selected wall thickness before finalizing the weld-end or bore representation.
- Use the listed stud bolt size and length as a reference, then verify the required engagement, gasket arrangement, flange facing, and project bolting specification.
- Keep the flange weight in lifting, handling, shipping, and installation planning where applicable.
- Review material, pressure-temperature service, gasket selection, welding requirements, and inspection requirements independently from the dimensional data.
Weld Neck Flange Versus Other Flange Types
A weld neck flange is attached by welding the pipe to the tapered hub. This differs from loose, threaded, socket-weld, and slip-on arrangements, which use different connection details and may have different installation or inspection considerations. The appropriate flange type depends on the piping specification, service conditions, fabrication method, and engineering review rather than nominal size alone.
Related Reference Content
For a complete piping detail, review this page alongside references for Class 900 flange dimensions, pipe wall thickness and schedules, gasket dimensions, and flange bolt terminology. The included DWG resource can support layout and detailing, but drawing users should confirm units, scaling, bore selection, and project-specific modifications before fabrication.
Frequently Asked Questions
What does the bore note mean?
The bore is not treated as a single universal value on this page because it depends on the pipe schedule and wall thickness selected for the connection. Confirm the pipe specification before completing the flange detail.
Why is a weld neck flange used?
Its tapered hub provides a gradual transition between the pipe and flange and supports a direct welded connection. The design is commonly selected where strength, stress distribution, and reliable pressure-piping connections are important.
Can the listed stud bolt information be used without checking the project specification?
No. The listed stud size and length are reference data for this flange entry. Final bolting should be checked against the mating flange, gasket arrangement, required engagement, material requirements, and project specification.
What is the DWG file useful for?
The DWG file can support piping layouts, drafting, dimensional coordination, and fabrication reference. It should be reviewed for the selected bore, drawing units, mating components, and any project-specific changes before release.