This reference page provides the dimensional information and CAD resource for a Weld Neck Flange 8 Inch Class 600. Use the listed values for drafting and reference, then verify the flange, pipe, gasket, and bolting requirements against the project specification before fabrication or installation.
The flange designation combines a nominal pipe size, a pressure class, and a weld neck connection style. These terms describe different aspects of the component and should not be treated as interchangeable. For related terminology, see the site references for pipe schedules, flange dimensions, raised-face flanges, and stud bolt sizing.
Weld Neck Flange 8″ Class 600
Weld Neck Flange 8″ Class 600 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 8″ Class 600 Dimensions
- Reference Standard: ANSI / ASME B16.5
- Nominal Pipe Size (NPS):8″
- DN Size: DN200
- Outside Diameter:419mm
- Flange Thickness:55.6mm
- Hub Diameter:273mm
- Bore Diameter: varies depending on pipe schedule and pipe wall thickness
- Raised Face Diameter:269.7mm
- Weight: 64kg
- Number of Bolts:12
- Stud Bolt Size: 1 1/8″ UNC (or M30) x 190 Long
- Hole Diameter: 1 1/4″ (31.75mm)
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 8″ Class 600 is commonly used for:
- Process piping systems
- Oil and gas lines
- Water and utility piping
- 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 8″ Class 600, which can be used for drafting, detailing, piping layout coordination, and fabrication reference.
Available Weld Neck Flange Class 600 Sizes
This size is part of the Weld Neck Flange Class 600 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 Weld Neck Flange Reference
The dimension list is most useful when coordinated with the connected pipe and mating flange. Nominal pipe size identifies the piping size category, while the flange outside diameter, thickness, hub geometry, bolt-hole pattern, and raised-face dimensions support layout and detailing work.
Pay particular attention to the bore. The bore is not treated as a single universal value in this reference because it varies with the selected pipe schedule and wall thickness. A drafter or fabricator should therefore confirm the connected pipe specification before finalizing the flange detail. This is also an important coordination point when using the DWG file in a piping layout or fabrication drawing.
Bolting and Mating Components
The listed stud bolt size, length, bolt count, and hole diameter describe the bolting arrangement shown for this flange reference. They should be checked together with the mating flange, gasket selection, washer requirements, thread engagement, and project assembly procedure. Do not select replacement bolts solely by nominal diameter; the complete connection and installation requirements must agree.
Weld Neck Flange CAD Use
The downloadable DWG can support preliminary drafting, equipment and piping coordination, and fabrication reference. Before issuing a drawing, check units, insertion scale, bore selection, weld preparation details, facing arrangement, and compatibility with the connected pipe and mating flange. A CAD file is a reference aid and does not replace design verification or project-approved fabrication documents.
Related PipeSTD References
- Pipe schedule reference: use it to coordinate wall thickness and bore selection.
- Flange terminology guide: compare weld neck, slip-on, blind, and socket weld flange features.
- Raised face flange reference: review facing terminology and gasket-interface coordination.
- CAD and DWG resources: find related flange sizes and piping components for layout work.
Frequently Asked Questions
What does the Class 600 designation mean?
Class 600 is the flange pressure-class designation used for this reference. It is not a standalone statement of allowable pressure for every service condition. Final pressure-temperature suitability depends on the applicable material, temperature, design rules, and project requirements.
Why can the bore diameter vary?
The bore must correspond to the connected pipe schedule and wall thickness. Because those selections can differ, the bore should be confirmed before ordering, modeling, or fabricating the flange.
Why is a weld neck flange used?
A weld neck flange has a tapered hub that transitions into the pipe connection. This geometry is intended to provide a robust welded connection and help manage stress at the flange-to-pipe transition. Actual design suitability still requires engineering review.
Can the DWG be used directly for fabrication?
The DWG is intended as a drafting and reference resource. Confirm its units, scale, bore, facing, weld details, material requirements, and project revisions before using it in an issued fabrication document.
What should be checked before installation?
Confirm the pipe size and schedule, flange material, mating flange, gasket, bolt and stud requirements, hole alignment, face condition, and applicable pressure-temperature requirements. The project specification and responsible engineer should govern where requirements differ.