Welding Neck Flange (WN)
Yunming Metal offers stainless steel welding neck flanges (WN) in DN15–DN3000 sizes. Butt-welded with tapered neck for high-pressure systems, they meet ANSI, EN, and JIS standards. Available in 304, 316L, 321, 904L, Class 150–2500. Ideal for industrial and offshore piping.
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Product Overview
Welding neck flanges (WN flanges) are designed with a long tapered hub that gradually transitions to the pipe wall thickness, offering excellent stress distribution. This design makes them ideal for high-pressure, high-temperature, or repeated bending applications. These flanges are butt-welded to the pipe, ensuring high strength and leak-free connections. Available in stainless steel grades such as 304, 316L, and 321, our WN flanges are manufactured in compliance with ANSI, EN, JIS, and other global standards.
Application Areas
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High-pressure oil and gas pipelines
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Chemical and petrochemical processing plants
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Boiler and pressure vessel systems
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Power generation and thermal plants
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Offshore platforms and marine engineering
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Refineries and industrial piping systems
Product Features
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Long tapered hub for superior stress distribution
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Butt-welded design ensures high-integrity connections
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Suitable for severe temperature and pressure conditions
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Size range from DN15 to DN3000 (approx. ½″ – 120″)
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Available in RF, RTJ, and custom sealing face types
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Supports Class 150 – 2500 and PN6 – PN100 pressure ratings
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Machined surface finish for precise sealing
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Compatible with ANSI B16.5, EN 1092-1, JIS B2220, and more
Technical Specifications
| Parameter | Range |
|---|---|
| Nominal Size (DN) | DN15 – DN3000 |
| Outside Diameter (OD) | 34 mm – 3200 mm (approx. 1⁵⁄₁₆″ – 126″) |
| Neck Length | 40 mm – 500 mm (approx. 1½″ – 20″) |
| Thickness (T) | 10 mm – 120 mm (approx. ³⁄₈″ – 4¾″) |
| Pressure Ratings | Class 150 – Class 2500 / PN6 – PN100 |
| Material Grades | ASTM A182 F304 / F316 / F316L / F321 / 310S / 904L / 2205 etc. |
| Standards | ANSI B16.5, EN 1092-1, JIS B2220, DIN, BS, GB, ISO etc. |
| Type | Welding Neck Flange (WN), raised face, RTJ face, custom face types |
| Connection Type | Butt-weld connection with pipe for structural integrity |
| Surface Finish | CNC machined, anti-rust oil coating |
| Application | Oil & gas, chemical, thermal power, boiler systems, marine piping, high-pressure industrial networks |
Manufacturing Process
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Raw Material Cutting – Flange blanks are cut from stainless steel billets or plates
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Forging & Heat Treatment – Flanges are forged and treated for strength and durability
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CNC Machining – Precision machining of bore, sealing face, bolt holes, and neck
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Welding End Shaping – Beveling and tapering to match pipe wall thickness
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Surface Finishing – Smooth finish with anti-corrosion coating applied
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Inspection & Marking – Dimensional inspection and standard-compliant stamping
FAQ
Q1: What makes welding neck flanges ideal for high-pressure applications?
A: The tapered hub and butt-weld connection offer excellent strength and stress resistance, especially under pressure or thermal expansion.
Q2: What size range do you supply?
A: We offer WN flanges from DN15 to DN3000 (approx. ½″ to 120″ OD).
Q3: Are your flanges compliant with international standards?
A: Yes, we manufacture to ANSI, EN, JIS, DIN, and ISO standards.
Q4: What materials are available for corrosive environments?
A: Options include 304, 316L, 321, 904L, duplex 2205, and more.
Q5: Do you offer third-party inspection and MTCs?
A: Absolutely. EN 10204 3.1/3.2 certificates and third-party inspection are available upon request.
Still have questions?
Feel free to contact us for more details or to discuss your custom stainless steel welding neck flange requirements. Our technical support team is ready to assist with specifications, certifications, and delivery.
