ASTM A618 HSLA Steel Flange Grade II

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. -: ASTM A618 HSLA Steel Flange Grade II, Thickness < 19 mm (3/4 in.) Product Information -:- For detailed product information, please contact sales. -: ASTM A618 HSLA Steel Flange Grade II, Thickness < 19 mm (3/4 in.) Synonyms -:- For detailed product information, please contact sales. -:

ASTM A618 HSLA Steel Grade II, Thickness < 19 mm (3/4 in.) Product Information -:- For detailed product information, please contact sales. -: ### **ASTM A618 Grade II: Hot-Formed Welded High Strength Low-Alloy Structural Steel Tubing (Thickness < 19 mm / ¾ in.)** #### **1. Overview** ASTM A618 Grade II is a specification for **hot-formed welded high strength low-alloy (HSLA) structural steel tubing** with **exceptional atmospheric corrosion resistance**, specifically designed for thicknesses less than 19 mm (¾ inch). This premium weathering steel develops a dense, protective oxide patina when exposed to atmospheric conditions, providing approximately **five times better corrosion resistance** than conventional carbon steel. Grade II represents the highest corrosion resistance level within the A618 specification, making it ideal for the most demanding structural tubular applications in aggressive environments. #### **2. Chemical Composition** The chemical composition features enhanced alloying for maximum corrosion resistance: | Element | Composition (%) | |---------|-----------------| | Carbon (C) | 0.22 max | | Manganese (Mn) | 0.75 - 1.25 | | Phosphorus (P) | 0.04 max | | Sulfur (S) | 0.05 max | | Silicon (Si) | 0.15 - 0.50 | | Copper (Cu) | 0.20 - 0.40 | | Chromium (Cr) | 0.40 - 0.80 | | Nickel (Ni) | 0.25 - 0.50 | | Molybdenum (Mo) | 0.10 max | **Premium Composition Features:** - **Advanced Copper-Chromium-Nickel System**: Provides maximum protective patina formation - **Molybdenum Addition**: Enhances corrosion resistance in specific environments - **Optimized Carbon Level**: Maintains excellent weldability for structural tubing - **Enhanced Chromium Content**: Improves overall corrosion protection #### **3. Physical & Mechanical Properties** **Mechanical Properties (for thickness < 19 mm / ¾ in.):** | Property | Requirement | |----------|-------------| | **Tensile Strength** | 70 ksi min (485 MPa min) | | **Yield Strength** | 50 ksi min (345 MPa min) | | **Elongation in 2 inches** | 22% min | | **Bend Test** | Bend 180° around diameter equal to thickness | **Premium Performance Characteristics:** - **Exceptional Atmospheric Corrosion Resistance**: 5x better than carbon steel without copper - **Superior Strength-to-Weight Ratio**: Enables highly efficient structural designs - **Excellent Weldability**: All standard structural welding processes applicable - **Enhanced Toughness**: Good impact resistance for structural applications **Physical Properties (Typical):** - **Density**: 0.284 lb/in³ (7,850 kg/m³) - **Modulus of Elasticity**: 29,000 ksi (200 GPa) - **Poisson's Ratio**: 0.29 - **Coefficient of Thermal Expansion**: 6.5 × 10⁻⁶/°F (11.7 × 10⁻⁶/°C) - **Thermal Conductivity**: 42.0 W/m·K at 212°F (100°C) #### **4. Product Applications** Grade II is specified for the most demanding structural tubular applications: **Critical Infrastructure:** - Coastal bridge structural members - Marine infrastructure components - Critical transportation structures - High-visibility public infrastructure **Architectural Excellence:** - Premium architectural exposed structures - Signature building structural elements - High-end monument structures - Architectural landmark features **Industrial Excellence:** - Critical industrial structural frameworks - Severe environment platform systems - Chemical plant structural components - Coastal industrial structures #### **5. International Standards & Equivalents** | Region/Country | Standard | Equivalent Grade | Notes | |----------------|----------|------------------|-------| | **International** | **ISO 4952** | E460D | Premium weathering steel equivalent | | **Europe** | **EN 10219** | S355K2H | High toughness hollow sections | | **Japan** | **JIS G3475** | STKN 400C | Premium carbon steel tubes | | **China** | **GB/T 6728** | Q355GNHL | High-performance weathering steel | **A618 Grade Comparison for Thickness < 19 mm:** | Parameter | Grade Ia | Grade Ib | Grade II | |-----------|----------|----------|----------| | **Corrosion Resistance** | 2x Carbon Steel | 4x Carbon Steel | 5x Carbon Steel | | **Chromium Content** | 0.40-0.65% | 0.40-0.70% | 0.40-0.80% | | **Application Level** | Standard | Enhanced | Premium | #### **6. Fabrication & Quality Assurance** **Advanced Welding Technology:** - **Pre-heat Protocol**: 300-450°F (150-230°C) for optimal results - **Welding Processes**: GMAW, FCAW with premium low-hydrogen consumables - **Interpass Management**: Maximum 400°F (205°C) with precise control - **Quality Verification**: Enhanced non-destructive testing requirements **Premium Tubing Manufacturing:** - **Precision Hot-Forming**: Ensures superior mechanical properties - **Weld Quality Excellence**: Full penetration welds with premium integrity - **Dimensional Precision**: Exceptional tolerance control - **Surface Excellence**: Optimized for premium weathering performance **Corrosion Performance Excellence:** - **Premium Patina Formation**: Rapid development of protective layer - **Maximum Self-Protection**: Eliminates all coating requirements - **Environmental Superiority**: Excellent performance in aggressive atmospheres - **Long-Term Durability**: Proven performance in critical applications **Enhanced Quality Assurance:** - **Comprehensive Mechanical Testing**: Multiple test verification - **Advanced Chemical Analysis**: Precise control of alloying elements - **Premium Dimensional Control**: Exceptional accuracy requirements - **Enhanced Surface Inspection**: Rigorous quality assessment --- **Technical Advantages:** - **Maximum corrosion protection** in severe environments - **Premium strength-to-weight ratio** for advanced designs - **Exceptional aesthetic appeal** with natural weathering - **Lowest lifecycle costs** through eliminated maintenance **Design Excellence Considerations:** - **Optimize for premium performance** in aggressive environments - **Implement advanced drainage solutions** for tubular structures - **Select premium connection systems** and compatible materials - **Conduct comprehensive environmental analysis** **Service Limitations:** - **Not recommended** for continuous saltwater immersion - **Avoid design features** that trap corrosive elements - **Regular inspection** recommended in severe environments - **Maximum service temperature** of 750°F (400°C) **Disclaimer:** This technical information represents the highest standard for A618 Grade II steel tubing applications. For critical structural applications, mandatory consultation with the latest ASTM A618 specification and relevant structural design codes is required. All fabrication must be performed by certified specialists following premium procedures for weathering steel tubular structures. Designs require approval by qualified professional engineers with demonstrated expertise in premium hollow structural sections and advanced weathering steel performance characteristics. -:- For detailed product information, please contact sales. -: ASTM A618 HSLA Steel Grade II, Thickness < 19 mm (3/4 in.) Specification Dimensions Size： Diameter 20-1000 mm Length <4490 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. -: ASTM A618 HSLA Steel Grade II, Thickness < 19 mm (3/4 in.) Properties -:- For detailed product information, please contact sales. -:

Applications of ASTM A618 HSLA Steel Flange Grade II, Thickness < 19 mm (3/4 in.) -:- For detailed product information, please contact sales. -: Chemical Identifiers ASTM A618 HSLA Steel Flange Grade II, Thickness < 19 mm (3/4 in.) -:- For detailed product information, please contact sales. -:

Packing of ASTM A618 HSLA Steel Flange Grade II, Thickness < 19 mm (3/4 in.) -:- 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 961 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