Long Weld Neck

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Long Weld Neck

A Long Weld Neck Flange is a type of flange characterized by an extended neck length that provides enhanced stress distribution and reduced turbulence in the piping system. It is designed to be welded to the pipe via a butt weld, ensuring a strong, leak-proof connection ideal for high-pressure and high-temperature applications.

Manufactured from high-quality materials such as carbon steel, stainless steel, and alloy steels, long weld neck flanges offer superior durability, corrosion resistance, and excellent mechanical strength. Their extended neck design helps in minimizing stress concentration and is suitable for critical systems in industries like oil & gas, petrochemical, power plants, and refineries.

Available in various pressure classes including Class 150, 300, 600, and above, long weld neck flanges ensure reliable performance in demanding environments. Their precision machining and butt weld connection provide a seamless integration with piping, making them ideal for high-stress and cyclic loading conditions.


Specifications of Long Weld Neck (Flange)

Specification Details
Product Long Weld Neck Flanges
Size Range 1/2" to 48" (DN15 to DN1200) – Custom sizes available
Pressure Ratings Class 150, 300, 600, 900, 1500, 2500 (As per ASME B16.5)
Face Type Raised Face (RF), Flat Face (FF), Ring Type Joint (RTJ) – on request
Standards ASME B16.5, ASME B16.47, ASTM A105, ASTM A182, MSS-SP-44, ISO 9001, EN 1092-1 (on request)
Material Grades Carbon Steel: ASTM A105, A350 LF2
Stainless Steel: 304, 304L, 316, 316L
Alloy Steel: ASTM A182 F1, F11, F22
Duplex Steel: UNS S31803, S32205
Nickel Alloys: Inconel 600/625, Monel 400, Hastelloy C276
Manufacturing Process Forged, Heat Treated, Machined
Ends Long Weld Neck with Butt Weld End
Surface Finish Black Painted, Pickled, Sand Blasted, Polished, Anti-Rust Coated
Testing & Certification Hydrostatic Test, NDT (UT, RT, MT), PMI, Hardness Test, TPI Inspection, Mill Test Certificates (EN 10204 3.1 / 3.2)
Applications Oil & Gas, Petrochemical, Power Generation, Refining, Marine, Chemical Processing, High-Pressure Steam, HVAC Systems
Special Features Enhanced Stress Distribution, Reduced Turbulence, High-Pressure Handling, Durable Performance, Corrosion Resistance, Suitable for High-Temperature Environments
Long Weld Neck Flange Design Features Extended Neck: Provides superior stress distribution and reduces turbulence.
Butt Weld Connection: Ensures strong, permanent, leak-proof joints.
High Strength: Forged construction for excellent mechanical properties.
Standards Compliant: Manufactured per ASME, ASTM, and ISO standards.
Precision Machined Bore: Matches pipe ID to ensure smooth flow and reduce erosion.

Key Features

Our Long Weld Neck Flanges are engineered for high-pressure, high-temperature piping systems. Designed for durability and precise alignment, they offer excellent stress distribution, strong butt weld connections, and superior resistance to fatigue and corrosion.

Extended Neck Design

Long weld neck flanges feature an extended neck that provides superior stress distribution, minimizing stress concentration at the base of the flange.

High Strength & Pressure Rating

Forged construction with butt weld ends ensures these flanges withstand high pressure and high-temperature environments effectively.

Corrosion & Fatigue Resistance

Manufactured using high-quality carbon steel, stainless steel, and alloy materials to provide excellent corrosion resistance and fatigue life in demanding applications.

Standards Compliance

Produced as per ASME B16.5, ASME B16.47, and ASTM standards, ensuring dimensional accuracy and compatibility with global piping systems.

Precision Machined Bore

Bore dimensions precisely match the pipe ID, ensuring smooth flow and reducing erosion and turbulence within the pipeline.

Versatile Industrial Use

Commonly used in oil & gas, petrochemical, power plants, shipbuilding, and chemical processing industries for critical high-pressure and high-temperature piping systems.