This reference page provides dimension data for a Weld Neck Flange 2 Inch Class 300, along with its listed weight, bolt information, and CAD drawing reference. Use the source values when checking a piping layout, preparing fabrication details, or coordinating a flange connection with the associated pipe.
The page is especially useful alongside references for pipe schedules, flange dimensions, pipe fittings, and piping terminology. Those related references help explain how the flange bore, gasket interface, bolting, and pipe wall selection interact during detailing.
Weld Neck Flange 2″ Class 300
Weld Neck Flange 2″ Class 300 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 2″ Class 300 Dimensions
- Reference Standard: ANSI / ASME B16.5
- Nominal Pipe Size (NPS):2″
- DN Size: DN50
- Outside Diameter:165mm
- Flange Thickness:20.6mm
- Hub Diameter:84mm
- Bore Diameter: varies depending on pipe schedule and pipe wall thickness
- Raised Face Diameter:92.1mm
- Weight: 3.7kg
- 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 2″ Class 300 is commonly used for:
- Process piping systems
- Oil and gas lines
- Water and utility piping
- Higher pressure service
- Pressure piping connections
- Industrial fabrication and maintenance work
CAD Drawing Download
This page includes the CAD drawing file for Weld Neck Flange 2″ Class 300, which can be used for drafting, detailing, piping layout coordination, and fabrication reference.
Available Weld Neck Flange Class 300 Sizes
This size is part of the Weld Neck Flange Class 300 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 toward the pipe. The pipe is welded to the hub, so the connection requires accurate alignment between the flange bore and the selected pipe outside diameter and wall thickness. The bore is therefore not treated as an independent universal value in this reference; it varies with the pipe schedule and wall thickness.
The listed outside diameter, thickness, hub dimensions, raised-face dimension, bolt count, hole diameter, and stud-bolt information describe the flange geometry and connection arrangement supplied by the source data. Confirm that mating flanges use the same facing arrangement and compatible bolting before using the information for fabrication or installation.
Using the CAD File
The downloadable DWG can support drafting, piping layout coordination, equipment-area detailing, and fabrication reference. Treat the drawing as a dimensional reference rather than a substitute for project specifications. Check units, drawing scale, bore selection, flange material, gasket requirements, and the applicable design documents before issuing fabrication drawings.
Practical Design Checks
- Match the flange bore to the selected pipe schedule and wall thickness.
- Verify the mating flange, raised-face condition, gasket, and bolting arrangement.
- Confirm material requirements and project pressure-temperature criteria separately from dimensional data.
- Use the applicable piping specification to determine installation, welding, inspection, and tightening requirements.
- For related work, compare this reference with the site resources for Class 300 flanges, weld neck flange sizes, and pipe dimension charts.
Frequently Asked Questions
What is a weld neck flange?
A weld neck flange is a flange with a long tapered hub that is welded directly to the pipe. The hub provides a gradual transition between the pipe and flange and is intended to support a robust welded connection.
Why does the bore vary for this flange?
The bore depends on the pipe schedule and wall thickness selected for the connection. Confirm the pipe specification before selecting or fabricating the flange.
What information is included in this reference?
The source data lists the flange dimensions, hub and raised-face information, weight, bolt quantity, stud-bolt size, and hole diameter. It also identifies ANSI / ASME B16.5-2020 as the basis of the dimension data.
Can the DWG file be used directly for fabrication?
The DWG is intended for drafting, detailing, layout coordination, and fabrication reference. Before release, verify the drawing against the project specification, selected pipe bore, material, gasket, bolting, and applicable engineering requirements.
Is Class 300 by itself enough to select a flange?
No. Flange selection also requires checking the applicable material, facing, pipe connection, gasket, bolting, and project pressure-temperature requirements. Final selection should follow the governing piping specification and engineering review.