Weld Neck Flanges
What are Weld Neck Flanges?
Weld neck flanges (WN flanges) are designed with a long tapered hub that is butt-welded to the pipe, ensuring excellent stress distribution and high-strength joints. These flanges are ideal for severe service conditions involving high pressure, temperature, or cyclic loading. Weld neck flanges are commonly used in oil refineries, petrochemical plants, and high-performance piping systems.
Asiad Steel Industries manufactures precision-grade weld neck flanges in stainless steel, carbon steel, and special alloys for critical applications worldwide.
Key Features
- Strong Welded Connection – Butt-weld ensures structural integrity and leak resistance.
- High Load Capacity – Suitable for high-pressure and high-stress applications.
- Long Service Life – Reduces vibration and stress concentrations.
- Wide Range of Sizes – Supports small to large-diameter piping.
- Industry Approved – Manufactured to ASME, EN, DIN, and BS standards.
Specifications
Mechanical Properties
Chemical Composition
Equivalent Grades
Weight Chart
Specifications
| Parameter | Details |
|---|---|
| Sizes | ½” to 60” (DN15 – DN1500) |
| Pressure Ratings | Class 150 to 2500, PN 6 to PN 250 |
| Face Types | RF, RTJ, FF |
| Standards | ASME B16.5, B16.47, EN 1092-1, DIN |
| Material Options | CS, SS 304/316, Alloy Steel, Inconel |
| Welding Type | Butt Weld |
| Property | Value |
|---|---|
| Tensile Strength | 485 – 750 MPa |
| Yield Strength | 205 – 450 MPa |
| Hardness | 120 – 250 HB |
| Elongation | 20% – 30% |
| Element | Composition (%) |
|---|---|
| Carbon (C) | 0.08 – 0.25 |
| Manganese | 0.60 – 1.65 |
| Silicon | 0.15 – 0.80 |
| Chromium | 16.0 – 18.0 (SS) |
| Nickel | 8.0 – 10.5 (SS) |
| Molybdenum | 2.0 – 3.0 (316) |
| Iron (Fe) | Balance |
| Standard | Equivalent Grade |
|---|---|
| ASTM | A105, A182 F304/F316 |
| ASME | B16.5, B16.47 |
| EN | 1.4301, 1.4404 |
| DIN | PN16/40, DIN 2633/2634 |
| Flange Size | Pressure Class | Approx. Weight (kg) |
|---|---|---|
| 2” | 150# | 3.8 |
| 4” | 300# | 14.6 |
| 6” | 600# | 27.4 |
| 10” | 900# | 76.8 |
| 16” | 1500# | 200.0 |
Applications of Weld Neck Flanges
Construction &
Infrastructure
Automotive & Heavy
Equipment
Manufacturing &
Fabrication
Medical & Laboratory
Equipment
Electrical &
Electronics Assembly
Oil, Gas & Petrochemical
Installations
Do you have questions?
What makes weld neck flanges suitable for critical services?
Their tapered hub and butt-welded joint distribute stress effectively, reducing fatigue and failure risk.
Do weld neck flanges come in different face types?
Yes, including Raised Face (RF), Ring Type Joint (RTJ), and Flat Face (FF).
What are the standard sizes available?
We offer sizes from ½” up to 60” in various pressure ratings.
Are weld neck flanges resistant to thermal expansion?
Yes, the weld joint offers flexibility and integrity under high-temperature conditions.
