ASTM A782 Low Alloy Steel Flange, Class 2

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 A782 Low Alloy Steel Flange, Class 2 Product Information -:- For detailed product information, please contact sales. -: ASTM A782 Low Alloy Steel Flange, Class 2 Synonyms -:- For detailed product information, please contact sales. -:

ASTM A782 Low Alloy Steel, Class 2 Product Information -:- For detailed product information, please contact sales. -: # **Product Introduction: ASTM A782/A782M Class 2 Low-Alloy Weathering Steel** **ASTM A782/A782M Class 2** is a premium **high-strength, low-alloy (HSLA) steel** designed for **structural applications demanding enhanced strength and superior atmospheric corrosion resistance**. As a **weathering steel**, it develops a dense, stable, and self-protecting oxide patina when exposed to the elements, offering **corrosion resistance four to six times greater than conventional carbon steel**. Class 2 provides a **higher minimum yield strength of 60 ksi (415 MPa)** compared to Class 1, making it suitable for more demanding structural applications where both material efficiency and long-term durability in unpainted conditions are critical. It is typically supplied in the **as-rolled or normalized condition**. --- ## **International Standard & Key Specifications** * **Primary Standard:** **ASTM A782/A782M** - Standard Specification for Pressure Vessel Plates, Alloy Steel and High-Strength Low-Alloy Steel, for Moderate and Lower Temperature Service. * **Context:** While categorized under pressure vessel standards for material quality, this steel is **primarily used in structural applications** due to its weathering properties. The specification ensures a higher-grade material suitable for critical exposed structures. * **Related Structural Standards:** * **ASTM A588/A588M** (Common weathering steel spec; Grade A/B/C/K). * **ASTM A6/A6M** - General Requirements for Rolled Structural Steel. * **AASHTO M270M/M270** - For bridge construction (when specified). * **Governing Standard:** **ASTM A20/A20M** - For general requirements of pressure vessel plates (applicable to plate product). --- ## **Chemical Composition (Weight %, max unless range is specified)** The chemistry is optimized for a higher strength level while maintaining and enhancing the weathering characteristics through carefully balanced alloying elements. | Element | Composition Range (%) | Role in Performance for Class 2 | | :--- | :--- | :--- | | **Carbon (C)** | ≤ 0.22 | Provides increased base strength compared to Class 1, while maintaining weldability. | | **Manganese (Mn)** | 0.75 - 1.35 | Primary solid-solution strengthener; slightly wider range for strength and hardenability control. | | **Phosphorus (P)** | 0.04 max | Contributes to atmospheric corrosion resistance. | | **Sulfur (S)** | 0.05 max | Impurity, controlled. | | **Silicon (Si)** | 0.15 - 0.50 | Deoxidizer and strengthener. | | **Copper (Cu)** | **0.30 - 0.50** | **Core weathering element.** Slightly higher minimum than Class 1 for robust patina formation. | | **Chromium (Cr)** | **0.50 - 0.90** | **Enhanced range.** Critical for forming a dense, adherent oxide layer; higher content improves corrosion resistance. | | **Nickel (Ni)** | **0.25 - 0.50** | Improves toughness and works synergistically with Cu and Cr. | | **Vanadium (V)** | 0.01 - 0.10 | Microalloy for grain refinement and precipitation strengthening, key to achieving higher yield strength. | **Key Distinction:** Class 2 typically features **higher minimums for Copper and Chromium**, and may utilize a tighter control of microalloys like Vanadium to achieve the **60 ksi yield strength** while ensuring excellent weathering performance. --- ## **Typical Physical & Mechanical Properties** Properties are for as-rolled or normalized structural plates. | Property | Value / Description | | :--- | :--- | | **Tensile Strength** | **550 - 690 MPa (80,000 - 100,000 psi)** | | **Yield Strength (min)** | **415 MPa (60,000 psi)** | | **Elongation in 2-in (50 mm) (min)** | 19% | | **Modulus of Elasticity** | ~200 GPa (29 x 10⁶ psi) | | **Density** | ~7.85 g/cm³ (0.284 lb/in³) | | **Charpy V-Notch Impact Toughness** | **Test Temperature:** Often specified for structural applications at **70°F (21°C)**. For bridges or low-temperature service, supplemental requirements apply (e.g., testing at 0°F / -18°C or -40°F / -40°C). Minimum avg. energy typically 15-20 ft-lbf (20-27 J). | | **Atmospheric Corrosion Resistance** | **4-6 times** greater than plain carbon steel. Potentially better than Class 1 in aggressive atmospheres due to higher Cr content. | | **Brinell Hardness (typical)** | 190 - 240 HBW | --- ## **Product Applications** Class 2 is specified for more demanding exposed structures where its higher strength allows for longer spans, lighter members, or increased load capacity, all with the low-maintenance benefit of weathering steel. **Primary Structural Applications:** 1. **Long-Span & Heavy-Duty Bridges:** * **Primary girders** and **truss members** for highway and railway bridges. * **Arch bridges** and **cable-stayed bridge pylons** (exposed elements). 2. **High-Rise & Signature Architecture:** * **Exposed structural frames** for buildings where the patina is an architectural feature. * **Long-span roof structures** and **atriums**. 3. **Critical Infrastructure:** * **Electrical Transmission Towers** in corrosive coastal or industrial environments. * **Offshore Platform Splash Zone Structures** (carefully engineered). * **Large Industrial Sculptures** and **monuments**. 4. **Transportation & Heavy Industry:** * **Portals and frames** for heavy industrial facilities. * **Support structures** in aggressive atmospheric conditions. --- ## **Advantages and Critical Fabrication & Design Considerations** * **Advantages:** * **Higher Strength with Weathering Benefits:** 60 ksi yield strength combined with excellent atmospheric corrosion resistance. * **Superior Lifecycle Economics:** Eliminates painting costs, reduces maintenance, and offers long service life. * **Material Efficiency:** Higher strength enables lighter, more elegant structural designs. * **Proven Performance in Aggressive Atmospheres:** Enhanced alloy content can offer better performance in industrial or coastal environments than lower-grade weathering steels. * **Critical Fabrication & Design Considerations:** * **Welding Requires Care:** Higher carbon equivalent necessitates **strict low-hydrogen welding procedures** (e.g., E8018-C3 electrodes). Preheat is often required. * **Imperative Detailing:** **Design must ensure complete drainage and ventilation.** Moisture traps are the primary cause of failure in weathering steel applications. Details like sealed weld butts and drip edges are crucial. * **Patina Mismatch at Welds:** Welds and the heat-affected zone (HAZ) will corrode differently and may not match the parent metal's patina. For cosmetic uniformity, a weathering-grade primer/touch-up may be needed. * **Initial Runoff Management:** The initial rust runoff (1-5 years) can stain adjacent materials. Design should incorporate features like drips, gutters, or sacrificial staining panels. * **Environmental Suitability:** Not for continuously wet, buried, or submerged service. Performance is optimal in open atmospheres with regular wet/dry cycles. * **Connection Design:** Contact with dissimilar metals (e.g., stainless fasteners, aluminum) requires insulation to prevent galvanic corrosion. Weathering steel fasteners are recommended. **In summary, ASTM A782 Class 2 is a high-performance weathering steel that delivers a 60 ksi minimum yield strength for efficient structural design while providing the signature low-maintenance durability of a protective patina. It is the material of choice for engineers and architects designing landmark exposed structures where strength, longevity, and aesthetics converge. Its successful application is fundamentally dependent on knowledgeable design that respects the material's unique characteristics and environmental needs.** -:- For detailed product information, please contact sales. -: ASTM A782 Low Alloy Steel, Class 2 Specification Dimensions Size： Diameter 20-1000 mm Length <4538 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 A782 Low Alloy Steel, Class 2 Properties -:- For detailed product information, please contact sales. -:

Applications of ASTM A782 Low Alloy Steel Flange, Class 2 -:- For detailed product information, please contact sales. -: Chemical Identifiers ASTM A782 Low Alloy Steel Flange, Class 2 -:- For detailed product information, please contact sales. -:

Packing of ASTM A782 Low Alloy Steel Flange, Class 2 -:- 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 1009 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