Steelage Alloys is a well-known Manufacturer, distributor, and exporter of Stainless Steel 316 Weld Neck Flanges and has high-quality products that are manufactured as a high-performance and durable tool. We have a lot of SS 316 weld neck flanges that have been known to be very resistant to corrosion, highly mechanically strong, and with long service life and are so suitable to be used in the harsh industrial settings like chemical processing units, oil and gas, power generation, and the marine industry.
Weld neck flange is also distinguished by a long tapered hub which progressively transfers the stress on the flange to the pipe to make it very structurally stable and with minimal turbulence at the junction. These flanges are made of Grade 316 stainless steel and they do have molybdenum which makes them resistant to pitting and crevice corrosion in cloride rich or acidic environments. It makes them much much better than typical 304-grade flanges in rough environments.
| Feature / Advantage | Description |
|---|---|
| High Corrosion Resistance | Excellent protection against chlorides, acids, and chemical corrosion, ideal for marine and chemical environments. |
| Superior Strength | Provides high tensile and yield strength, ensuring durability in high-pressure applications. |
| Leak-Proof Connection | Long tapered hub design evenly distributes stress, preventing leaks in welded joints. |
| Temperature Endurance | Performs efficiently in both high-temperature and cryogenic conditions. |
| Excellent Weldability | Easily welded using TIG, MIG, or arc methods without losing strength or corrosion resistance. |
| Smooth Flow Transition | Hub taper ensures smooth flow with minimal turbulence or pressure drop. |
| Low Maintenance | Resistant to pitting and oxidation, reducing the need for frequent maintenance. |
| Precision Machining | Manufactured to tight dimensional tolerances for reliable fit and sealing. |
| Versatile Pressure Ratings | Available in ANSI Class 150, 300, 600, 900, 1500, and 2500. |
| Long Service Life | Robust construction and corrosion-proof finish extend operational lifespan. |
| Element | Percentage (%) | Function / Benefit |
|---|---|---|
| Chromium (Cr) | 16.0 – 18.0 | Provides excellent corrosion and oxidation resistance. |
| Nickel (Ni) | 10.0 – 14.0 | Enhances ductility and resistance to acids. |
| Molybdenum (Mo) | 2.0 – 3.0 | Improves resistance to pitting and crevice corrosion. |
| Carbon (C) | ≤ 0.08 | Low carbon reduces carbide precipitation during welding. |
| Manganese (Mn) | ≤ 2.00 | Adds strength and toughness. |
| Silicon (Si) | ≤ 1.00 | Improves heat and oxidation resistance. |
| Phosphorus (P) | ≤ 0.045 | Maintains good weldability. |
| Sulfur (S) | ≤ 0.030 | Improves machinability. |
| Iron (Fe) | Balance | Base metal providing overall structure. |
| Parameter | Available Range / Specification |
|---|---|
| Nominal Size (NB) | ½" to 48" (DN 15 to DN 1200) |
| Pressure Ratings (Class) | 150, 300, 600, 900, 1500, 2500 (as per ASME B16.5) |
| Flange Face Type | Raised Face (RF), Flat Face (FF), Ring Type Joint (RTJ) |
| Thickness / Hub Height | As per ANSI / ASME B16.5 & B16.47 standards |
| Bore Size Tolerance | ±0.5 mm or as per customer requirement |
| Bolt Circle Diameter Tolerance | ±0.8 mm |
| Outer Diameter Tolerance | ±1.0 mm |
| Facing Finish | 3.2 to 6.3 μm Ra for RF / FF surfaces |
| Bevel Angle | 37.5° ± 2.5° (standard weld bevel) |
| Connection Type | Butt-weld neck with full penetration weld |
| Standard Dimensions | ANSI / ASME B16.5, B16.47 Series A & B, EN 1092-1 |
| Customization | Available for non-standard sizes and special pressure classes |
| Type of Weld Neck Flange | Description |
|---|---|
| Standard Weld Neck Flange (WNRF) | Long tapered hub ensures smooth stress distribution and strong weld connection. |
| Long Weld Neck Flange (LWN) | Extended neck provides better reinforcement and alignment with the pipeline. |
| Reducing Weld Neck Flange | Connects pipes of varying diameters directly without separate reducers. |
| Integral Weld Neck Flange | Machined from a single forged piece for maximum strength and leak resistance. |
| Heavy Duty Weld Neck Flange | Thicker walls designed to handle high-pressure and heavy-duty operations. |
| Ring Type Joint (RTJ) Weld Neck Flange | Features a metal ring groove for secure, high-pressure sealing. |
| Custom Weld Neck Flange | Manufactured to specific size, design, or material requirements. |
| Aspect | Description |
|---|---|
| Connection Type | Butt-weld for strong, leak-proof joints. |
| Alignment | Ensure accurate pipe and flange bore alignment. |
| Welding | Use TIG/MIG with ER316L filler for best results. |
| Gasket | Select compatible type – spiral wound, PTFE, or graphite. |
| Bolt Tightening | Apply torque in cross-pattern sequence. |
| Surface Finish | Maintain Ra 3.2–6.3 μm for proper sealing. |
| Post-Weld Cleaning | Pickle and passivate for corrosion resistance. |
| Property | Description |
|---|---|
| Corrosion Resistance | Excellent resistance to pitting, crevice, and general corrosion. |
| Marine Atmosphere | Performs reliably in saltwater and coastal conditions. |
| Chemical Resistance | Resists attack from acids, alkalis, and chlorides. |
| Oxidation Resistance | Stable under continuous service up to 870°C. |
| Stress Corrosion Cracking | Superior resistance in chloride-bearing environments. |
| Acidic Media | Suitable for sulfuric, acetic, and phosphoric acid exposure. |
| Surface Protection | Passivated and polished surfaces enhance longevity. |
| Overall Performance | Ideal for harsh industrial, marine, and chemical settings. |
| Process | Description |
|---|---|
| Visual Check | Ensures smooth surface and accurate dimensions. |
| Hydrostatic Test | Checks pressure strength and leak-proof performance. |
| NDT (UT/RT) | Detects internal cracks or weld defects. |
| Chemical Test | Confirms correct SS 316 composition. |
| Mechanical Test | Verifies strength, hardness, and durability. |
| Dimensional Check | Matches ASME B16.5/B16.47 standards. |
| Surface Finish | Pickled, polished, or mirror as required. |
| Marking | Grade, size, and heat number for traceability. |
Steelage Alloys is a reputed manufacturer and supplier of SS 316 Weld Neck Flange manufactured by quality assurance and precision engineering as well as customer satisfaction. The company employs premium stainless steel and sophisticated production modes to make all the flanges to be of international standards. Having decades of experience in the industry, Steelage Alloys is able to provide high quality, corrosion resistant, and durable products that are quota to be used in various industries. They are a client of choice serving customers at any corner of the world due to the quality of their products, delivery on time, and their customer-centric attitude.
Round Bar
Analytic
Cut to Length
Centering
Heating
Perforation
Inspection of Size
Pickling
Inspection of Surface
Lubricating
Cold Drawing
Degreasing
Annealing
Cut
Straightening
Pickling / Passivating
Inspection
Analytic
Marking
Packing & Shipping
Formula: m = (OD - THK) × THK (mm) × L (m) × ρ (g/cm³) × π ÷ 1000
OD = Outside Diameter, THK = Wall Thickness, L = Length
ρ = Density, π = 3.1415926...
Plastic Bag
Wooden case
By Sea
By Air