Stainless Steel 309S Flanges are specially designed for applications that demand excellent resistance to high temperatures, oxidation, and corrosion. These flanges are widely used in industries where heat strength, durability, and long service life are critical. As an experienced ASME SA182 F309S Flanges Manufacturer in India, we supply premium-quality flanges that meet international standards and perform reliably in extreme environments.
Stainless Steel 309S is a low-carbon version of SS 309, offering improved weldability while maintaining outstanding resistance to scaling at elevated temperatures. This makes 309S stainless steel flanges an ideal choice for petrochemical plants, power generation units, furnaces, heat exchangers, and refineries.
What Are Stainless Steel 309S Flanges?
SS 309S Flanges are pipe connecting components manufactured from a high-alloy austenitic stainless steel containing high chromium and nickel content. This chemical composition provides exceptional resistance to oxidation up to 1035°C and intermittent service up to 1095°C.
Compared to standard stainless steel grades, 309 / 309S flanges offer superior performance in high-temperature and mildly corrosive environments. The “S” grade has lower carbon content, which minimizes carbide precipitation during welding and enhances corrosion resistance after fabrication.
Stainless Steel 309S Flange Standards & Specifications
- Material Grade: ASTM A182 / ASME SA182 F309S
- UNS Number: SS UNS S30908
- Werkstoff No: 1.4833
- Flange Standard: ANSI / ASME B16.5, ASME B16.47
- Pressure Class: 150, 300, 600, 900, 1500, 2500
- Size Range: ½” NB to 48” NB
- Manufacturing Type: Stainless Steel 309S Forged Flanges
Types of Stainless Steel 309S Flanges We Offer
We manufacture and stock a wide variety of Stainless Steel 309 Flanges to meet diverse industrial requirements.
➤ Stainless Steel 309S Weld Neck Flange
Stainless Steel 309s Weld Neck Flange is designed for high-pressure and high-temperature pipelines. The long tapered hub provides excellent stress distribution, making it ideal for critical services in refineries and power plants.
➤ ANSI B16.5 SS 309S Blind Flange
The ANSI B16.5 SS 309S Blind Flange is used to close pipeline ends or pressure vessel openings. It allows easy inspection and future expansion while offering high strength and temperature resistance.
➤ SS 309S RTJ Flange
As an experienced SS 309S RTJ Flange Manufacturer, we supply Ring Type Joint flanges for extremely high-pressure and high-temperature services. These flanges ensure leak-proof sealing in oil & gas and petrochemical applications.
➤ SS UNS S30908 Orifice Flange
SS UNS S30908 Orifice Flange is used to measure fluid flow in pipelines. These flanges are commonly installed in pairs and are suitable for aggressive and high-temperature media.
➤ SS Werkstoff No 1.4833 Socket Weld Flanges
SS Werkstoff No 1.4833 Socket Weld Flanges are designed for small-diameter, high-pressure pipelines. They provide smooth flow characteristics and strong weld joints.
➤ ASME SA182 F309S Spectacle Blind Flanges
ASME SA182 F309S Spectacle Blind Flanges are used to completely isolate pipeline sections. These are especially useful in maintenance shutdowns where positive isolation is required.
Applications of Stainless Steel 309S Flanges
Based on industry usage, SS 309s flanges are widely used in:
- Petrochemical and oil & gas plants
- Power generation and thermal plants
- Heat exchangers and boilers
- Furnaces and kilns
- Cement and steel industries
- Chemical processing units
Their reliability under extreme conditions makes them a preferred choice for engineers and plant operators.
Mechanical Properties – Stainless Steel 309S Forged Flanges
| Property | Value |
|---|---|
| Tensile Strength | 515 MPa (minimum) |
| Yield Strength (0.2% Offset) | 205 MPa (minimum) |
| Elongation (%) | 40% (minimum) |
| Hardness (Brinell) | ≤ 217 HB |
| Impact Strength | Good toughness at elevated temperatures |
| Modulus of Elasticity | 193 GPa |
| Shear Modulus | 77 GPa |
Chemical Composition – ASTM A182 F 309S Flange
| Element | Composition (%) |
|---|---|
| Carbon (C) | ≤ 0.08 |
| Chromium (Cr) | 22.00 – 24.00 |
| Nickel (Ni) | 12.00 – 15.00 |
| Manganese (Mn) | ≤ 2.00 |
| Silicon (Si) | ≤ 0.75 |
| Phosphorus (P) | ≤ 0.045 |
| Sulfur (S) | ≤ 0.030 |
| Iron (Fe) | Balance |
Physical Properties – 309s stainless steel flanges
| Physical Property | Value |
|---|---|
| Density | 8.0 g/cm³ |
| Melting Point | 1399 – 1454°C |
| Thermal Conductivity | 14.2 W/m·K |
| Specific Heat Capacity | 500 J/kg·K |
| Electrical Resistivity | 0.78 µΩ·m |
| Coefficient of Thermal Expansion | 15.5 µm/m·°C (20–100°C) |
| Magnetic Permeability | Non-magnetic (may become slightly magnetic after cold working) |
ASME SA182 F309S Flanges Manufacturer in India
As a trusted Manufacturer and Exporter of Stainless Steel 309S Flanges, we serve domestic and international markets with precision-engineered products. Our flanges are exported to the Middle East, Europe, Southeast Asia, and Africa, meeting strict international quality requirements.
We understand real project challenges such as tight delivery schedules, dimensional accuracy, and performance under pressure. That practical experience reflects in every 309 / 309s flange we supply.
Why Engineers Trust Our Stainless Steel 309S Flanges
- Consistent material quality
- Compliance with ASTM, ASME, and ANSI standards
- Competitive pricing without quality compromise
- Custom sizes and pressure ratings available
- Reliable after-sales support
Our goal is to supply flanges that work flawlessly in real operating conditions—not just on paper.
Trusted Manufacturer and Exporter of Stainless Steel 309S Flanges
Stainless Steel 309S Flanges are a smart investment for industries operating under high temperatures and demanding environments. With excellent oxidation resistance, strong mechanical properties, and long service life, ASTM A182 F309S flanges deliver dependable performance where failure is not an option.
If you are looking for high-quality SS 309S RTJ Flange, ANSI B16.5 SS 309S Blind Flange, or Stainless Steel 309s Weld Neck Flange, we are ready to support your project with proven expertise and reliable products.
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