Weld Neck Flange

Weld Neck Flange

Weld neck flange (WN flange) has a neck that redistributes stress of the pipe, reducing pressure concentration at the flange base.
It is ideal for pipelines operating under high or low temperatures and high pressure conditions, especially when PN exceeds 2.5 MPa.

Our Supply Range

• Material: Carbon, Alloy and Stainless Steel
• Standards: ASTM A105, ASTM A182
• Sizes: 1/2” to 24”, Customized up to 48”
• Thickness: Schedule 10(S) to SCH 160
• Pressure Ratings: Class 150 to 2500
• Face Type: RF, RTJ

Types of Weld Neck Flange

Reducing Weld Neck Flange

This type combines a reducer and a flange, allowing it to be welded directly to a smaller pipe.

Long Weld Neck Flange (LWN)

The neck resembles an extended pipe connected to a flange, commonly used as a nozzle for columns or barrels.
It is available in standard and heavy thickness options.

Face Types

Raised Face (RF): Features a small raised area around the bore where the gasket is placed. The height varies depending on pressure rating.

Ring Type Joint (RTJ): Includes a groove for a metal gasket, designed for high-pressure and high-temperature applications.

Standards

• ASTM A105/N (Carbon Steel)
• ASME B16.5, ASME B16.47
• BS 3293
• DIN Standards (PN 1 to PN 40)

Applications & Features

Weld neck flanges are mainly used in medium and high-pressure pipelines.
Due to the welding process, installation requires higher labor and material costs, but provides superior strength and durability.