This reference provides the listed dimensions, weight, and fastening details for a Weld Neck Flange 4 Inch Class 150. Use the source values for preliminary drafting, layout coordination, and component identification, then verify the final selection against the project specification.
The flange is identified by nominal pipe size and pressure class, while the bore must be coordinated with the pipe schedule and wall thickness. That distinction is important when matching the flange to a specific pipe connection.
Weld Neck Flange 4″ Class 150
Weld Neck Flange 4″ 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 4″ Class 150 Dimensions
- Reference Standard: ANSI / ASME B16.5
- Nominal Pipe Size (NPS):4″
- DN Size: DN100
- Outside Diameter:229mm
- Flange Thickness:22.4mm
- Hub Diameter:135mm
- Bore Diameter: varies depending on pipe schedule and pipe wall thickness
- Raised Face Diameter:157.2mm
- Weight: 7.7kg
- Number of Bolts:8
- Stud Bolt Size: 5/8″ UNC (or M16) x 90 Long
- Hole Diameter: 3/4″ (19.05mm)
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 4″ 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 4″ 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
A weld neck flange connects to the pipe through its tapered hub. The hub provides a gradual transition from the flange body to the pipe, which is why this flange type is commonly considered for systems subject to pressure, temperature changes, or repeated loading. Final suitability still depends on the complete piping design, material specification, joining procedure, and applicable project requirements.
Understanding the Dimension Entries
- Overall flange dimensions: The outside diameter, flange thickness, hub diameter, and raised face diameter support layout, clearance, and detailing work.
- Bore diameter: The bore is not a single universal value for every pipe connection. It must match the pipe schedule and wall thickness selected for the installation.
- Fastener information: The number of bolts, stud bolt size, and hole diameter describe different connection features. Do not treat the hole diameter as the stud diameter.
- Weight: The listed weight is useful for handling, support, and material-estimating discussions, but lifting and support decisions require project-specific verification.
Drafting and Coordination Notes
Use the accompanying DWG file as a drafting and coordination reference. Before issuing fabrication drawings, check the flange facing, bore, gasket arrangement, bolt compatibility, material, and connection details against the piping specification. Related PipeSTD references may include pipe dimensions, pipe schedules, flange types, gasket terminology, and other CAD/DWG resources.
Frequently Asked Questions
What does a weld neck flange do?
A weld neck flange is welded directly to the pipe through a long tapered hub. Its geometry helps provide a gradual transition between the pipe and flange.
Why does the bore depend on the pipe schedule?
Pipe schedules can have different wall thicknesses for the same nominal pipe size. The flange bore therefore needs to be selected to suit the actual pipe wall and connection detail.
Are the stud bolt size and hole diameter the same thing?
No. The stud bolt size identifies the fastener, while the hole diameter describes the clearance opening through the flange. Both must be checked when selecting compatible bolting.
Can the CAD file be used for fabrication?
The DWG file is useful for drafting, detailing, and layout coordination. Fabrication should proceed only after the drawing, material, bore, gasket, bolting, and project requirements have been verified.
Is Class 150 by itself a complete pressure design specification?
No. The applicable pressure-temperature rating depends on factors such as material and service conditions. Confirm the required rating and project specification before installation or fabrication.