Domestic Weld Neck Flanges

Weld Neck Flanges for Heavy-Duty Industrial Piping 

Weld neck flanges (also called WN flanges) are a standard choice in industrial pipelines where strength, durability and reliable flow are critical. Built with a long, tapered hub that is butt-welded directly to a pipe, they create a smooth, gradual transition from flange to pipe. This design helps distribute stress evenly and reduces turbulence or erosion inside the line. Weld neck flanges are often preferred over other options like blind flanges or socket weld flanges when a seamless connection and high-strength performance are required.

Because of their structural advantages, weld neck flanges are often specified for demanding conditions - high pressure, high temperature, frequent stress cycles, or critical fluid transfer.

Variants and Specifications

This collection includes standard weld neck flanges, raised face weld neck flanges and long weld neck flanges. Each option serves a different purpose based on piping layout, face configuration and system design requirements.

Raised face weld neck flanges are common in many ASME B16.5 applications, similar to other piping solutions such as buttweld fittings, ensuring smooth bore alignment and system reliability. Long weld neck flanges are often used on vessels, tanks, or setups where an extended hub is part of the engineering layout. Materials typically include carbon steel, stainless steel, and other industrial-grade selections used across U.S. process facilities.

Where Weld Neck Flanges Are Used

Industrial users rely on weld neck flanges in multiple environments:

• High-pressure steam, oil/gas, chemical, or water pipelines
• Process plants, refineries, power-generation facilities
• Heavy mechanical systems, fabrication setups, pressure vessels and tanks
• Pipelines where seamless bore alignment and minimal flow disruption are required

Because the flange bore matches pipe bore exactly, fluid flow remains smooth and there’s less risk of erosion or turbulence - important in corrosive or abrasive fluid systems.

Discover Weld Neck Flanges at Trupply

On Trupply, you’ll find weld neck flanges in multiple materials and pressure classes - from standard RF/FF to long-neck styles. Suitable for new installations or maintenance projects, these flanges support a broad array of industrial applications. Use them when reliability, safety and long-term performance matter in your piping infrastructure.

Sizes

Size & Dimension table for Flanges

Materials

A105 - The standard forged carbon steel piping components for ambient and high temperature / pressure systems

SS304 - A common standard for stainless steel due to its malleability, high corrosive resistance weld-ability  

SS316 - A molybdenum stainless steel that provides excellent tensile, creep and stress-rupture strengths at elevated temperatures

Material Description for Flanges

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