What Is a Weld Neck Flange?

What Is a Weld Neck Flange?

A Weld Neck Flange (WN Flange) is one of the most commonly used flange types in industrial piping systems. It features a long tapered hub that provides a smooth transition between the pipe and the flange, helping to reduce stress concentration.

Unlike slip-on flanges, a weld neck flange is connected to the pipe using a full penetration butt weld. This design offers excellent strength and makes it suitable for high-pressure, high-temperature, and critical service applications.

Advantages of Weld Neck Flanges

• Excellent mechanical strength
• High pressure resistance
• Better fatigue performance
• Reliable sealing
• Long service life

Typical Applications

Weld neck flanges are widely used in:

• Oil & Gas
• Petrochemical Plants
• Power Generation
• Offshore Platforms
• Refineries

When selecting a flange, engineers should consider operating pressure, temperature, and the working environment. Choosing the correct flange type can significantly improve system safety and reduce maintenance costs.

As a professional China steel flange manufacturer, we supply weld neck flanges in carbon steel, stainless steel, and alloy steel according to ASME, DIN, EN, and JIS standards.