This reference page provides the dimensional, weight, and bolting information for a Weld Neck Flange 8 Inch Class 1500. Use the source data below when checking flange selection, piping layouts, fabrication drawings, or connection details.
The page also explains how the weld neck geometry, bore selection, raised face, and stud bolting relate to practical piping work. For coordinated design, compare this reference with the applicable pipe schedule, gasket specification, flange material, and project requirements.
Weld Neck Flange 8″ Class 1500
Weld Neck Flange 8″ Class 1500 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 1500 Dimensions
- Reference Standard: ANSI / ASME B16.5
- Nominal Pipe Size (NPS):8″
- DN Size: DN200
- Outside Diameter:483mm
- Flange Thickness:92.1mm
- Hub Diameter:292mm
- Bore Diameter: varies depending on pipe schedule and pipe wall thickness
- Raised Face Diameter:269.7mm
- Weight: 136kg
- Number of Bolts:12
- Stud Bolt Size: 1 5/8″ UNC (or M42) x 290 Long
- Hole Diameter: 1 3/4″ (44.45mm)
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 1500 is commonly used for:
- Process piping systems
- Oil and gas lines
- Refinery and petrochemical piping
- Extremely 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 1500, which can be used for drafting, detailing, piping layout coordination, and fabrication reference.
Available Weld Neck Flange Class 1500 Sizes
This size is part of the Weld Neck Flange Class 1500 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 Read This Weld Neck Flange Reference
The dimensional list identifies the flange envelope and connection features needed for drafting and preliminary coordination. Outside diameter and thickness describe the flange body, while hub diameter and the long tapered hub help define the transition from the flange to the pipe.
The bore is not treated as a single universal value in this reference because it depends on the pipe schedule and wall thickness selected for the connection. Confirm the mating pipe before preparing a fabrication drawing. A mismatch between the flange bore and pipe outside diameter can affect fit-up, welding details, and the finished internal flow path.
Bolting and Mating Components
Use the listed bolt count, stud size, bolt-hole diameter, and bolt length together when checking a flange assembly. These details must be coordinated with the mating flange, gasket type, washer arrangement, accessible wrench space, and the project bolting procedure. The listed stud length should not be treated as a substitute for a complete joint calculation or field-fit review.
Design and Drafting Checks
- Confirm that the nominal pipe size and DN designation match the intended piping line.
- Verify the mating flange class, facing arrangement, material specification, and pressure-temperature requirements.
- Check the pipe schedule before finalizing the bore or weld preparation.
- Use the CAD drawing as a drafting and layout aid, then verify critical details against approved project documents.
- Review clearances around the bolt circle, flange face, weld area, insulation, and adjacent components.
For related design work, this page can be used alongside internal references for pipe schedules, flange terminology, gasket selection, piping isometrics, and DWG detailing. The flange dimensions support coordination, but final selection and fabrication remain subject to engineering review and the governing project specification.
Frequently Asked Questions
What does a weld neck flange do?
A weld neck flange connects to the pipe through a butt weld and uses a tapered hub to provide a gradual transition between the pipe and flange. This geometry is intended to improve stress distribution compared with simpler flange profiles.
Why does the bore depend on the pipe schedule?
Pipe schedules use different wall thicknesses for the same nominal pipe size. Because the internal opening changes with wall thickness, the flange bore must be checked against the actual pipe selected for the line.
Can the listed bolt size be used for every installation?
The listed stud bolt information describes this reference configuration. Confirm the mating flange, gasket, washers, joint design, material requirements, and project installation procedure before ordering or installing bolting.
Is the CAD file ready for fabrication without review?
The DWG file is useful for drafting, layout coordination, and reference. Fabrication should proceed only after the drawing is checked against approved dimensions, materials, weld details, tolerances, and project requirements.
Does Class 1500 alone determine allowable pressure?
No. The applicable pressure-temperature capability depends on factors such as material, temperature, flange design, gasketed joint conditions, and the governing project requirements. Use the stated reference standard and obtain engineering confirmation for the service.