This reference provides the dimensional data, bolt information, weight, and CAD resource for a Weld Neck Flange 5 Inch Class 1500. Use the listed values for drafting and coordination, then verify the flange configuration against the pipe schedule, material specification, gasket arrangement, and project requirements before fabrication or installation.
The page is especially useful when coordinating a flange connection with pipe dimensions and schedules, stud bolts, gaskets, and related piping fittings. The source data identifies the NPS, DN designation, outside diameter, thickness, hub dimensions, raised face, bolt pattern, stud bolt size, hole diameter, and weight.
Weld Neck Flange 5″ Class 1500
Weld Neck Flange 5″ 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 5″ Class 1500 Dimensions
- Reference Standard: ANSI / ASME B16.5
- Nominal Pipe Size (NPS):5″
- DN Size: DN125
- Outside Diameter:375mm
- Flange Thickness:73.2mm
- Hub Diameter:197mm
- Bore Diameter: varies depending on pipe schedule and pipe wall thickness
- Raised Face Diameter:185.7mm
- Weight: 64kg
- Number of Bolts:8
- Stud Bolt Size: 1 1/2″ UNC (or M39) x 250 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 5″ 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 5″ 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 Use the Weld Neck Flange Dimensions
A weld neck flange is attached to the pipe through its tapered hub. The hub provides a gradual transition between the pipe and flange, which is why weld neck designs are commonly selected for demanding piping connections and systems exposed to pressure, temperature changes, or cyclic service.
For drafting, the outside diameter, flange thickness, raised face diameter, and bolt-hole information define the primary connection envelope. The hub diameter helps describe the welded transition, while the bore must be checked against the actual pipe wall thickness and schedule. The listed bore is therefore not a single universal value for every pipe configuration.
Bolt and Gasket Coordination
The bolt count, stud bolt designation, bolt length, and hole diameter should be reviewed together rather than as isolated dimensions. Confirm that the selected studs, nuts, washers where specified, and gasket are compatible with the mating flange and the assembly procedure. Bolt length can also depend on flange facing, gasket thickness, washer use, and the design of the opposite flange.
Class and Project Verification
The Class 1500 designation identifies the flange class used for the referenced connection. It should not be treated as a complete design approval by itself: allowable service conditions depend on factors such as material, temperature, gasket selection, bolting, and the governing project requirements. Use the source dimensions for reference and have the final connection checked by the responsible piping or mechanical engineer.
Related Reference Topics
- Compare this page with other Class 1500 weld neck flange sizes when selecting a matching connection.
- Use the site’s pipe schedule and pipe dimension references to confirm the required bore.
- Review related flange facing, gasket, and stud bolt references during connection detailing.
- Open the available DWG CAD file for layout, drafting, and fabrication coordination, subject to project verification.
Frequently Asked Questions
What is the bore of a Weld Neck Flange 5 Inch Class 1500?
The bore varies with the pipe schedule and pipe wall thickness. Confirm the bore against the actual pipe specification instead of assuming that every NPS 5 flange has the same opening.
What bolt information is provided for this flange?
The reference lists the number of bolts, stud bolt size and length, and hole diameter. Check these details against the mating flange, gasket, nuts, washers, and the project bolting specification before assembly.
Why is a weld neck flange used?
Its long tapered hub creates a gradual transition to the pipe and is intended to support a strong welded connection. This configuration is often considered for piping subject to pressure, temperature fluctuation, or cyclic loading, with final suitability requiring engineering review.
Can the listed dimensions be used for fabrication?
They can support preliminary drafting and coordination, but fabrication should follow the approved project documents and verified material, pipe schedule, bore, gasket, bolt, and pressure-temperature requirements.
Is a CAD file available for this flange?
Yes. The page includes a DWG download for the Weld Neck Flange 5 Inch Class 1500. Review the drawing against the dimensional reference and project requirements before using it for fabrication or construction.