This reference provides the dimension data, bolt information, weight, and CAD resource for a Weld Neck Flange 1/2 Inch Class 150. Use it when preparing piping layouts, checking fabrication details, or coordinating flange connections with pipe and fittings.
The flange dimensions should be read together with the pipe schedule, bore requirement, gasket arrangement, and project specifications. The listed bore is schedule-dependent, so it should not be treated as a single universal opening for every pipe configuration.
Weld Neck Flange 1/2″ Class 150
Weld Neck Flange 1/2″ Class 150 is widely used in piping systems that require strong, leak-resistant flange connections. It features a long tapered hub that provides excellent stress distribution and is commonly applied in process piping, utility lines, and industrial systems where welding strength and reliability are important.
This dimension data is based on ANSI / ASME B16.5-2020.
Weld Neck Flange 1/2″ Class 150 Dimensions
- Reference Standard: ANSI / ASME B16.5
- Nominal Pipe Size (NPS):1/2″
- DN Size: DN15
- Outside Diameter:89mm
- Flange Thickness:9.7mm
- Hub Diameter:30mm
- Bore Diameter: varies depending on pipe schedule and pipe wall thickness
- Raised Face Diameter:34.9mm
- Weight: 0.9kg
- Number of Bolts:4
- Stud Bolt Size: 1/2″ UNC (or M14) x 55 Long
- Hole Diameter: 5/8″ (15.875mm)
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 1/2″ Class 150 is commonly used for:
- Process piping systems
- Oil and gas lines
- Water and utility piping
- High-temperature service
- Pressure piping connections
- Industrial fabrication and maintenance work
CAD Drawing Download
This page includes the CAD drawing file for Weld Neck Flange 1/2″ Class 150, which can be used for drafting, detailing, piping layout coordination, and fabrication reference.
Available Weld Neck Flange Class 150 Sizes
This size is part of the Weld Neck Flange Class 150 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 welded to the hub, while the flange face provides the bolted connection for a matching flange. This arrangement makes the hub geometry and weld detail important during drafting, fabrication, inspection, and installation.
Dimension and connection checks
- Outside diameter and thickness: Use these values when checking flange clearances, fabrication details, and available space around the connection.
- Hub and bore: The hub supports the welded transition. The bore must be coordinated with the pipe schedule and wall thickness selected for the piping system.
- Raised face: Confirm that the mating flange and gasket arrangement are compatible with the stated face configuration.
- Bolt information: Check the listed bolt count, hole diameter, stud size, and length against the mating flange, gasket thickness, washers, and project installation requirements.
- Weight: Treat the listed weight as a reference for handling, material takeoff, and layout coordination. Actual delivered weight can be affected by material, facing, coating, and manufacturing tolerances.
Useful related references
For a complete piping check, connect this page with the site’s pipe schedule reference, flange dimensions, gasket reference, and piping terminology guide. A related DWG flange library can also help users compare adjacent sizes and coordinate flange geometry in CAD.
The downloadable DWG is useful for drafting and coordination, but the drawing should be checked against the project specification and the selected pipe, gasket, and mating flange before fabrication. Do not use the flange class designation alone to establish an allowable design condition; material, temperature, assembly details, and the governing project requirements must also be verified.
Frequently Asked Questions
What does the bore depend on?
The bore depends on the pipe schedule and pipe wall thickness. Confirm the selected pipe configuration before using the flange for fabrication or modeling.
What information is provided for the bolting?
The reference lists the number of bolts, stud bolt size and length, and hole diameter. These details should be checked with the mating flange, gasket arrangement, washers, and project bolting requirements.
Can the DWG file be used directly for fabrication?
The DWG is intended as a drafting, detailing, layout, and fabrication reference. Verify its geometry and connection details against the applicable project specification before releasing fabrication documents.
Why is a weld neck flange used?
Its tapered hub provides a gradual transition between the pipe and flange and helps distribute stress at the welded connection. Final selection still depends on the piping design, materials, service conditions, and engineering review.
What should be checked before installation?
Confirm the flange material, pipe schedule, bore, gasket type, bolt arrangement, bolt length, mating flange, and applicable project requirements before installation.