This reference provides the source dimensions, weight, and bolting details for a Weld Neck Flange 1 Inch Class 1500. Use the data for piping layout, preliminary detailing, CAD coordination, and fabrication review, while confirming the final selection against the project specification.
The listed bore is schedule-dependent, so the flange should be matched to the pipe outside diameter, wall thickness, and weld preparation required for the connection. For related terminology, see the site’s references for pipe schedules, flange types, and NPS and DN pipe sizes.
Weld Neck Flange 1″ Class 1500
Weld Neck Flange 1″ 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 1″ Class 1500 Dimensions
- Reference Standard: ANSI / ASME B16.5
- Nominal Pipe Size (NPS):1″
- DN Size: DN25
- Outside Diameter:149mm
- Flange Thickness:28.6mm
- Hub Diameter:52mm
- Bore Diameter: varies depending on pipe schedule and pipe wall thickness
- Raised Face Diameter:50.8mm
- Weight: 3.7kg
- Number of Bolts:4
- Stud Bolt Size: 7/8″ UNC (or M24) x 125 Long
- Hole Diameter: 1″ (25.4mm)
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 1″ 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 1″ 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
A weld neck flange has a tapered hub that transitions from the flange body to the pipe. The pipe is joined by welding through the hub, making the weld preparation and pipe fit-up important parts of fabrication review. The hub also provides a clear visual distinction from slip-on, threaded, and socket weld flange designs.
The dimensional list separates the main flange geometry from connection details. Outside diameter, thickness, hub diameter, raised face diameter, bolt count, bolt-hole diameter, and stud dimensions are used for layout and mating-flange coordination. The bore diameter is not a single universal value in this reference because it varies with pipe schedule and wall thickness.
Important Matching Checks
- Confirm that the flange bore matches the selected pipe schedule and intended weld connection.
- Check that the mating flange has compatible facing, bolt-hole layout, and bolting requirements.
- Review gasket selection and facing condition before assembly.
- Verify the material specification and pressure-temperature requirements for the actual service.
- Use the downloadable DWG as a drafting aid, then confirm critical dimensions against the project-controlled data before fabrication.
For broader coordination, connect this reference with internal pages covering flange bolt dimensions, pipe wall thickness, gasket types, raised face flanges, and piping CAD blocks. These related references help distinguish nominal size from actual bore and clarify how flange geometry affects layout.
Using the CAD Download
The DWG file can support piping arrangement, equipment connection studies, detail drawings, and fabrication markups. CAD geometry should be checked against the listed source data and the project’s approved flange, pipe, gasket, and bolting specifications before it is used for manufacture or construction.
Weld Neck Flange 1 Inch Class 1500 FAQ
What is the bore of this weld neck flange?
The bore varies according to the pipe schedule and wall thickness. Select the bore by matching the flange to the actual pipe specification rather than relying only on nominal pipe size.
How many bolts are listed for this flange?
The source reference lists four bolts. Confirm the mating flange and project bolting specification before ordering or assembly.
What bolt size is listed?
The reference lists 7/8 inch UNC, or M24, studs with the stated source length. Confirm thread form, material, engagement, and final length for the gasket and flange assembly.
Why use a weld neck flange?
Its tapered hub provides a gradual transition to the pipe and is intended for a welded connection. This configuration is commonly selected where flange strength, weld integrity, and resistance to service loading are important design considerations.
Can the DWG be used directly for fabrication?
The DWG is intended as a drafting and coordination reference. Fabrication should follow the approved project drawings, material requirements, welding procedure, inspection requirements, and verified flange data.
Does Class 1500 alone define allowable service pressure?
No. The applicable pressure-temperature capability depends on factors such as material, temperature, facing, design requirements, and the governing project specification. Confirm the rating with the responsible engineer and approved documentation.