Outokumpu SAF 2304® Duplex Stainless Steel Flange

1,We Manufacturing processes are primarily classified into four types: 1:Forging, 2:Casting, 3:Cutting, 4:Rolling. 2,We can manufacture in accordance with these standards. Standards: GB Series (Chinese Standards), JB Series (Machinery Standards), HG Series (Chemical Industry Standards), ASME B16.5 (American Standards), BS4504 (British Standards), DIN (German Standards), and JIS (Japanese Standards). Internationally, there are two primary systems of pipe flange standards: the European system, represented by the German DIN standards (including those of the former Soviet Union), and the American system, represented by the US ANSI pipe flange standards. Other common standards include: the Chinese Ministry of Machinery Industry standards (JB series), the Ministry of Chemical Industry standards (HG series), the Chinese National Standard *GB/T 9112–9124-2010 Steel Pipe Flanges*, as well as US standards (ASME B16.5), British standards (BS4504), German standards (DIN), Japanese standards (JIS), and marine standards (CBM), among others. The nominal pressure ratings for the PN series are designated by "PN" and comprise the following nine levels: PN2.5, PN6, PN10, PN16, PN25, PN40, PN63, PN100, and PN160. The nominal pressure ratings for the Class series are designated by "Class" and comprise the following six levels: Class150, Class300, Class600, Class900, Class1500, and Class2500. Flange Classification 1. **According to Chemical Industry Standards:** Flanges are classified as follows: Plate Flat Welding Flange (PL), Necked Flat Welding Flange (SO), Necked Butt Welding Flange (WN), Integral Flange (IF), Socket Welding Flange (SW), Threaded Flange (Th), Butt Welding Ring Loose Flange (PJ/SE), Blind Flange (BL), Flat Welding Ring Loose Flange (PJ/PJ), and Lined Blind Flange (BL(s)). 2. **According to Petrochemical (SH) Industry Standards:** Flanges are classified as follows: Threaded Flange (PL), Butt Welding Flange (WN), Flat Welding Flange (SO), Socket Welding Flange (SW), Loose Flange (LJ), and Blind Flange (no specific designation). 3. **According to Machinery (JB) Industry Standards:** Flanges are classified as follows: Integral Flange, Butt Welding Flange, Plate Flat Welding Flange, Butt Welding Ring Plate Loose Flange, Flat Welding Ring Plate Loose Flange, Lap Joint Ring Plate Loose Flange, and Blind Flange. 4. **According to Connection Method/Type:** Flanges are classified as follows: Plate Flat Welding Flange, Necked Flat Welding Flange, Necked Butt Welding Flange, Socket Welding Flange, Threaded Flange, Blind Flange, Necked Butt Welding Ring Loose Flange, Flat Welding Ring Loose Flange, Ring-Type Joint (RTJ) Flange and Blind Flange, Large-Diameter Plate Flange, Large-Diameter High-Neck Flange, Figure-8 Blind Plate, Butt Welding Ring Loose Flange, etc. 5. **According to the Component Being Connected:** Flanges can be classified into Vessel Flanges and Pipe Flanges. 6. **According to Structural Type:** Flanges include Integral Flanges, Threaded Flanges, Flat Welding Flanges, Butt Welding Flanges, Lap Joint (Loose/Swivel) Flanges, and Blind Flanges. A flange—also referred to as a flange plate or rim—is a component used to connect shafts to one another, or, more commonly, to join the ends of pipes. Flanges are also utilized at the inlet and outlet ports of equipment to facilitate connections between two devices—for instance, the flange on a speed reducer. A "flange connection" or "flanged joint" refers to a detachable joint assembly comprising three interconnected elements—a flange, a gasket, and bolts—that together form a sealed structural unit. In the context of piping systems, a "pipe flange" specifically denotes a flange used for plumbing within the installation; when applied to equipment, it refers to the inlet or outlet flange of that specific device. Flanges feature a series of holes through which bolts are inserted to securely fasten the two flanges together, while a gasket placed between the flanges ensures a leak-proof seal. Flanges are broadly categorized into three types: threaded (screw-in) flanges, welded flanges, and clamp-type flanges. Flanges are invariably used in pairs; threaded flanges are suitable for low-pressure piping applications, whereas welded flanges are required for systems operating at pressures exceeding 4 kilograms per square centimeter. A sealing gasket is inserted between the two flange plates, which are then firmly secured using bolts. The thickness of a flange—as well as the specifications of the bolts used to fasten it—vary depending on the specific pressure rating required for the application. When connecting equipment such as water pumps or valves to piping systems, the corresponding connection points on these devices are often manufactured in the shape of a matching flange; this method of attachment is also referred to as a "flange connection." Generally, any connecting component that utilizes bolts to join and seal the perimeters of two flat surfaces—such as the joints in ventilation ducts—is termed a "flange"; such components may collectively be classified as "flange-type parts." However, since such a connection often constitutes merely a *portion* of a larger device—for instance, the interface between a flange and a water pump—it would be inappropriate to classify the entire water pump itself as a "flange-type part." Conversely, smaller components—such as valves—that feature such flanged interfaces may indeed be appropriately categorized as "flange-type parts." -:- For detailed product information, please contact sales. -: Outokumpu SAF 2304® Duplex Stainless Steel Flange Product Information -:- For detailed product information, please contact sales. -: Outokumpu SAF 2304® Duplex Stainless Steel Flange Synonyms -:- For detailed product information, please contact sales. -:

Outokumpu SAF 2304® Duplex Stainless Steel Product Information -:- For detailed product information, please contact sales. -: # **Product Name: Outokumpu SAF 2304® Duplex Stainless Steel (UNS S32304 / EN 1.4362)** ## **Introduction** Outokumpu SAF 2304® is a **molybdenum-free, standard duplex stainless steel** that established the foundation for the modern duplex family. It offers a balanced microstructure of roughly 50% austenite and 50% ferrite, delivering a **compelling combination of high strength and excellent corrosion resistance**, specifically targeting superior performance over Type 316L austenitic stainless steel. SAF 2304® provides **approximately double the yield strength of 316L** and **significantly improved resistance to chloride stress corrosion cracking (SCC)**, making it a cost-effective, high-performance material for moderately aggressive environments. ## **Key Features** * **High Strength-to-Weight Ratio:** Yield strength (~400 MPa min.) is nearly double that of 316L, enabling significant weight reduction in structural components, tanks, and pressure vessels. * **Superior Stress Corrosion Cracking (SCC) Resistance:** Excellent resistance to chloride-induced SCC, a common failure mode for 300-series austenitic stainless steels, making it ideal for environments containing chlorides. * **Good General Corrosion Resistance:** Offers better resistance to pitting and crevice corrosion than 304L and comparable or better general corrosion resistance than 316L in many environments. * **Cost-Effective Alternative:** Provides a more affordable alternative to molybdenum-bearing standard duplex grades (like 2205) when the enhanced pitting resistance of molybdenum is not required, while still offering the core duplex benefits of strength and SCC resistance. --- ## **1. Chemical Composition (Typical Weight %)** The composition is designed for a balanced duplex structure without molybdenum. | Element | Content (%) | Element | Content (%) | | :------------- | :------------ | :------------- | :---------- | | Chromium (Cr) | 21.5 - 24.5 | Nickel (Ni) | 3.0 - 5.5 | | Molybdenum (Mo)| ≤ 0.6 | **Nitrogen (N)**| **0.05 - 0.20** | | Manganese (Mn) | ≤ 2.5 | Copper (Cu) | 0.05 - 0.60 | | Silicon (Si) | ≤ 1.0 | Carbon (C) | ≤ 0.030 | | Phosphorus (P) | ≤ 0.040 | Sulfur (S) | ≤ 0.015 | | **Iron (Fe)** | **Balance** | | | **Key Alloying Note:** The defining characteristic is the **absence of deliberate molybdenum (Mo) addition**. Corrosion resistance is achieved through high chromium and controlled nitrogen. **PREN Calculation:** PREN = %Cr + 3.3(%Mo) + 16(%N) ≈ **24 - 27** --- ## **2. Physical & Mechanical Properties (Typical - Annealed Condition)** | Property | Value / Range | | :-------------------------------------------- | :-------------------------------- | | Density | 7.8 g/cm³ | | Thermal Conductivity (20°C) | ~19 W/m·K | | Coefficient of Thermal Expansion (20-100°C) | ~13.0 x 10⁻⁶ /K | | Modulus of Elasticity | 200 GPa | | **Tensile Strength (Rm)** | **600 - 820 MPa** | | **Yield Strength (Rp0.2)** | **≥ 400 MPa** | | **Elongation (A in 50mm)** | **≥ 25 %** | | Hardness (Brinell) | 220 - 280 HBW | | **Impact Toughness (Charpy V-notch)** | **> 100 J at -40°C** | --- ## **3. Product Forms & Applications** **Available Product Forms:** * Sheet and Plate * Bar and Wire * Welded and Seamless Pipe & Tube * Strip **Primary Applications (Replacing 304L/316L where SCC is a risk):** SAF 2304® is ideal for applications requiring higher strength and SCC resistance than 316L, without the need for molybdenum's pitting resistance. * **Construction & Architecture:** Structural components, bridges, roofing, and façades in coastal or de-icing salt environments. * **Water & Wastewater Treatment:** Storage tanks, pressure pipes, basin covers, and structural supports. * **Chemical & Process Industry:** Tanks, vessels, and piping for mildly corrosive chemicals, organic acids, and sulfate-containing media. * **Pulp & Paper Industry:** Storage tanks, washer drums, and equipment exposed to neutral sulfite liquors. * **Food & Beverage:** Brewing tanks, fermentation vessels, and structural supports. * **Heat Exchangers:** For cooling water systems with moderate chloride levels where 316L may suffer from SCC. * **Transportation:** Structural parts in railcars and ships. --- ## **4. International Standards & Approvals** SAF 2304® is the original duplex grade and is well-established in international standards. | Standard Type | Standard Number & Designation | Notes | | :------------------ | :--------------------------------------------------------------------------------------------------------------------------- | :-------------------------------------------------------------------- | | **Unified Numbering System (UNS)** | **S32304** | The standard UNS designation for this molybdenum-free duplex alloy. | | **EN / EURONORM (Europe)** | **1.4362** | The common European material number. | | | EN 10088-2: Sheet/Plate/Strip
EN 10088-3: Bars
EN 10216-5: Seamless pressure tubes | Widely covered in European product standards. | | **ASTM (USA)** | **ASTM A240** (Plate/Sheet/Strip)
**ASTM A789/A790** (Seamless/Welded Pipe & Tube)
**ASTM A276** (Bar) | Fully standardized in key ASTM material specifications. | | **Other Standards** | JIS G4304 / G4305 (Japan) - SUS323J1
GB/T 20878 (China) | Included in major national standards. | --- ## **Important Technical & Procurement Note** SAF 2304® is a **proprietary Outokumpu product** that meets international standards. For procurement, specifying **"UNS S32304"** or **"EN 1.4362"** alongside the Outokumpu brand name is recommended. * **Fabrication:** Good weldability using standard duplex practices. Filler metals like 2209 are commonly used. Forming requires higher forces than for austenitic grades. * **Selection Rationale:** Its primary advantage is offering **duplex-level strength and SCC resistance at a lower cost than 2205**. It is an **excellent upgrade from 316L** where pitting resistance is adequate but SCC failure is a concern. It is **not suitable** for applications requiring the high pitting resistance of molybdenum-bearing grades (e.g., seawater, strong chlorides). * **Certification:** Always require a **material test certificate (MTC/CMTR)** confirming compliance with the ordered standard (e.g., ASTM A240). -:- For detailed product information, please contact sales. -: Outokumpu SAF 2304® Duplex Stainless Steel Specification Dimensions Size： Diameter 20-1000 mm Length <7287 mm Size:We can customized as required Standard： Per your request or drawing We can customized as required Properties（Theoretical） Chemical Composition -:- For detailed product information, please contact sales. -: Outokumpu SAF 2304® Duplex Stainless Steel Properties -:- For detailed product information, please contact sales. -:

Applications of Outokumpu SAF 2304® Duplex Stainless Steel Flange -:- For detailed product information, please contact sales. -: Chemical Identifiers Outokumpu SAF 2304® Duplex Stainless Steel Flange -:- For detailed product information, please contact sales. -:

Packing of Outokumpu SAF 2304® Duplex Stainless Steel Flange -:- For detailed product information, please contact sales. -: Standard Packing: -:- For detailed product information, please contact sales. -: Typical bulk packaging includes palletized plastic 5 gallon/25 kg. pails, fiber and Steel Flange drums to 1 ton super sacks in full container (FCL) or truck load (T/L) quantities. Research and sample quantities and hygroscopic, oxidizing or other air sensitive materials may be packaged under argon or vacuum. Solutions are packaged in polypropylene, plastic or glass jars up to palletized 3758 gallon liquid totes Special package is available on request. E FORUs’ is carefully handled to minimize damage during storage and transportation and to preserve the quality of our products in their original condition