Welding Neck Flanges — High-Strength Connection | DIN / ANSI / ASME Standards

Welding Neck Flanges are designed for high-pressure and high-temperature piping systems. Featuring a long tapered hub that gradually transitions to the wall thickness of the pipe, these flanges ensure excellent stress distribution and strong, leak-proof joints, making them ideal for critical service applications.

Standards & Pressure Ratings

Manufactured to international standards, Welding Neck Flanges offer reliable performance across a wide range of pressure classes:

DIN Standards

• DIN 2631 – PN 6
• DIN 2632 – PN 10
• DIN 2633 – PN 16
• DIN 2634 – PN 25
• DIN 2635 – PN 40

ASME / ANSI Standards

• ASME B16.5 (Class 150 – Class 1500)
• ASME B16.47 Series B for larger diameters

Key Features

• Tapered Hub Design – Minimizes stress concentrations and provides excellent reinforcement for high-pressure systems.
• Butt-Welded Connection – Ensures a smooth flow transition between pipe and flange, reducing turbulence and erosion.
• High Integrity Seal – Ideal for critical applications where tight sealing and long service life are essential.
• Wide Pressure Range – Available from PN 6 up to PN 40 (DIN) and up to Class 1500 (ASME).
• Material Options – Available in carbon steel, stainless steel, and special alloys for various industrial applications.

Typical Dimensions

• Nominal Sizes: DN 10 – DN 1000 (DIN) / ½” – 24” (ASME)
• Raised Face or RTJ Options depending on pressure class
• Bolt Circle & Hole Patterns: As per DIN / ASME dimensional standards
• Bore Dimensions match the pipe schedule for optimal fit and flow

Applications

• High-pressure steam and water systems
• Oil & gas pipelines and refineries
• Petrochemical and power generation industries
• High-temperature process lines
• Shipbuilding and offshore applications