This reference covers the dimensional data, bolt details, and drafting considerations for a 10-inch Class 400 weld neck flange. Use the listed values for comparison and layout work, then verify the project specification before ordering, machining, or installing the flange.
The page is especially useful alongside a pipe schedule reference, flange type guide, and piping terminology reference. Those related resources help connect the flange dimensions with pipe wall thickness, facing details, gasket selection, and bolting requirements.
Weld Neck Flange 10″ Class 400
Weld Neck Flange 10″ Class 400 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 10″ Class 400 Dimensions
- Reference Standard: ANSI / ASME B16.5
- Nominal Pipe Size (NPS):10″
- DN Size: DN250
- Outside Diameter:444mm
- Flange Thickness:53.8mm
- Hub Diameter:321mm
- Bore Diameter: varies depending on pipe schedule and pipe wall thickness
- Raised Face Diameter:323.8mm
- Weight: 71kg
- Number of Bolts:16
- Stud Bolt Size: 1 1/8″ UNC (or M30) x 190 Long
- Hole Diameter: 1 1/4″ (31.75mm)
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 10″ Class 400 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 10″ Class 400, which can be used for drafting, detailing, piping layout coordination, and fabrication reference.
Available Weld Neck Flange Class 400 Sizes
This size is part of the Weld Neck Flange Class 400 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 is aligned with the pipe and welded through its tapered hub. The hub provides a gradual transition from the pipe to the flange body, which is why this flange style is commonly reviewed for systems subject to pressure, temperature changes, or cyclic loading. Actual suitability still depends on the complete design, material, joining procedure, and applicable project requirements.
Dimension and Bore Selection
The outside diameter, thickness, hub diameter, and raised face diameter describe the flange geometry used for layout and coordination. The bore is different: it must correspond to the pipe’s actual inside diameter and wall thickness. Review the relevant pipe schedule dimensions before selecting or checking the bore, because the flange listing does not establish one universal bore for every pipe configuration.
Bolting and Connection Checks
The bolt count, stud size, bolt-hole diameter, and bolt length should be checked as a group. Confirm that the mating flange has the same bolt pattern and compatible facing arrangement. Bolt length can also depend on flange thickness, gasket details, washers, and the mating component, so the listed value should be verified against the assembled joint rather than treated as an isolated purchasing instruction.
Using the CAD Drawing
The downloadable DWG can support piping layout, drafting, interference review, and fabrication reference. Before using it as a manufacturing basis, compare the drawing with the dimension list, project tolerances, flange material requirements, pipe schedule, gasket selection, and the latest approved engineering documents. A CAD file is a coordination aid and does not replace design verification.
Related Reference Topics
- Compare this item with other Class 400 weld neck flange sizes when developing a piping arrangement.
- Use a flange facing guide to review raised-face and mating-connection terminology.
- Check the site’s stud bolt and nut reference when preparing a joint assembly.
- Review related CAD and DWG piping resources for drafting and layout coordination.
Frequently Asked Questions
What is the nominal size of this weld neck flange?
The source listing identifies the flange as NPS 10 inches and DN250. Confirm the pipe designation and mating component before procurement.
Does the listed flange include one fixed bore size?
No. The bore varies with the pipe schedule and wall thickness. Select or verify the bore using the actual pipe dimensions required by the project.
What bolt information is provided?
The reference lists the number of bolts, stud bolt size, bolt length, and hole diameter. These details should be checked against the mating flange, gasket arrangement, washers, and final joint assembly.
Can the DWG be used directly for fabrication?
The DWG is intended for drafting, detailing, layout coordination, and fabrication reference. Confirm all dimensions, tolerances, materials, bore requirements, and approved project documents before fabrication.
Is Class 400 a direct pressure value?
No. A flange class designation should not be treated as a universal pressure value. The allowable pressure-temperature performance depends on the applicable standard, material, temperature, and project requirements.
What should be confirmed before installation?
Verify the flange material, pipe schedule, bore, gasket type, bolt details, facing compatibility, pressure-temperature requirements, and applicable engineering documents before installation.