This reference page provides the listed dimensions and installation-related details for a Weld Neck Flange 1 Inch Class 150. Use the dimensional data for preliminary piping layout, drafting, flange selection, and fabrication review.
The flange has a tapered hub that transitions into the pipe through a butt-welded connection. That geometry is important when comparing weld neck flanges with other flange types, especially where connection stiffness, alignment, and stress distribution must be considered.
For a complete piping check, review this page together with the applicable pipe schedule, flange facing, gasket, stud bolt, and pressure-temperature rating references. The bore is not a single universal dimension because it depends on the selected pipe wall thickness.
Weld Neck Flange 1″ Class 150
Weld Neck Flange 1″ 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″ Class 150 Dimensions
- Reference Standard: ANSI / ASME B16.5
- Nominal Pipe Size (NPS):1″
- DN Size: DN25
- Outside Diameter:108mm
- Flange Thickness:12.7mm
- Hub Diameter:49mm
- Bore Diameter: varies depending on pipe schedule and pipe wall thickness
- Raised Face Diameter:50.8mm
- Weight: 0.9kg
- Number of Bolts:4
- Stud Bolt Size: 1/2″ UNC (or M14) x 65 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″ 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″ 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 Use This Weld Neck Flange Reference
The listed outside diameter, flange thickness, hub diameter, raised face diameter, bolt-hole information, and weight describe the flange configuration covered by this page. These values are useful for checking clearances, preparing fabrication drawings, coordinating piping layouts, and reviewing a CAD model.
Bore and Pipe Schedule
The bore should be checked against the pipe schedule and actual pipe wall thickness before ordering or fabrication. A flange may have the correct nominal pipe size while still requiring a different bore configuration for the selected pipe. This is one reason flange dimensions should be reviewed with the matching pipe dimensions and schedules reference rather than treated as an isolated component.
Understanding the Bolt Information
The bolt data identifies the required bolt-hole arrangement and the listed stud-bolt designation. Confirm the mating flange, gasket arrangement, thread compatibility, available engagement, and final bolt length during project review. Bolt selection should also account for the complete joint assembly, not only the flange hole diameter.
Why the Tapered Hub Matters
The long tapered hub provides a gradual transition between the pipe and flange. Compared with a simple flat flange form, this geometry is intended to support a more controlled load path at the welded connection. Actual suitability depends on the piping design, material specification, welding procedure, operating conditions, and engineering verification.
Using the CAD File
The downloadable DWG file can support drafting, piping layout coordination, detailing, and fabrication reference. Treat the drawing as a dimensional aid and verify the selected bore, mating components, gasket, bolts, and project requirements before issuing fabrication or installation documents.
Related Reference Topics
- Pipe schedules: compare wall thickness and bore requirements for the nominal pipe size.
- Flange dimensions: review related flange types and pressure-class configurations.
- Gaskets and bolt sets: coordinate the complete bolted-joint assembly.
- CAD and DWG resources: find compatible piping components for layout and detailing.
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.
Does the flange bore always have one fixed diameter?
No. The bore depends on the pipe schedule and pipe wall thickness selected for the application. Confirm the required bore before fabrication or procurement.
What bolt information is listed for this flange?
The reference identifies the number of bolt holes, hole diameter, and stud-bolt designation for the listed configuration. Check the mating flange and complete joint assembly before installation.
Can the DWG file be used for fabrication?
The DWG file is provided as a drafting, layout, detailing, and fabrication reference. Final fabrication documents should be checked against the project specification and verified dimensions.
Is Class 150 by itself enough to select the flange?
No. Selection also requires review of the applicable material, pipe schedule, gasket, bolt details, pressure-temperature requirements, and project design conditions.