ASTM A387 Alloy Steel Flange, Grade 7, 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 A387 Alloy Steel Flange, Grade 7, Class 2 Product Information -:- For detailed product information, please contact sales. -: ASTM A387 Alloy Steel Flange, Grade 7, Class 2 Synonyms -:- For detailed product information, please contact sales. -:

ASTM A387 Alloy Steel, Grade 7, Class 2 Product Information -:- For detailed product information, please contact sales. -: ### **Product Introduction: ASTM A387/A387M Alloy Steel, Grade 7, Class 2** **1. Overview** ASTM A387 Grade 7 Class 2 is a chromium-molybdenum (Cr-Mo) alloy steel plate specifically designed for service in welded pressure vessels and other high-temperature applications. This grade is known for its excellent strength and resistance to oxidation and corrosion at elevated temperatures, typically up to about 600°C (1112°F). The "Class 2" designation indicates that the material is supplied in the normalized and tempered heat treatment condition, which provides an optimal combination of high strength and good toughness. **2. Key International Standards** * **Primary Standard:** **ASTM A387/A387M** - Standard Specification for Pressure Vessel Plates, Alloy Steel, Chromium-Molybdenum. * This standard covers the chemical, mechanical, and heat treatment requirements. * **Dimensional Standards:** * **ASTM A20/A20M** - Standard Specification for General Requirements for Steel Plates for Pressure Vessels. This provides supplementary requirements for testing, inspection, tolerances, etc. * **Equivalent Standards:** * **EN / DIN:** 16Mo3 (A comparable European grade, though not an exact equivalent). * **JIS:** SCMV 28 (Japanese standard for Cr-Mo steel for pressure vessels). **3. Chemical Composition (Weight %)** The chemical composition is a critical factor in achieving the desired high-temperature properties. The ladle analysis must conform to the following limits: | Element | Composition (%) | | :--- | :--- | | Carbon (C) | 0.05 - 0.17 | | Manganese (Mn) | 0.40 - 0.65 | | Phosphorus (P), max | 0.025 | | Sulfur (S), max | 0.025 | | Silicon (Si) | 0.50 - 0.80 | | Chromium (Cr) | 1.90 - 2.60 | | Molybdenum (Mo) | 0.87 - 1.13 | *Note: Trace elements may be restricted by customer requirements or supplementary standards.* **4. Mechanical & Physical Properties** The mechanical properties are guaranteed in the normalized and tempered condition. **Mechanical Properties (at room temperature):** | Property | Value | | :--- | :--- | | Tensile Strength | 485 - 620 MPa (70 - 90 ksi) | | Yield Strength (min) | 275 MPa (40 ksi) | | Elongation in 2 in. (50 mm), (min) | 22% | | **Hardness (typical)** | **~145-190 HB** | **Approximate Physical Properties:** * **Density:** 7.86 g/cm³ (0.284 lb/in³) * **Melting Point:** ~ 1425 - 1520 °C (2600 - 2770 °F) * **Modulus of Elasticity:** 200 GPa (29 x 10⁶ psi) * **Thermal Conductivity:** ~ 36.0 W/m·K (at 100°C) * **Coefficient of Thermal Expansion:** ~ 11.5 x 10⁻⁶ /K (20-100°C) *Note: Physical properties can vary with temperature and should be verified for specific design calculations.* **5. Product Applications** ASTM A387 Gr 7 Cl 2 is predominantly used in the construction of pressure vessels and components that operate in high-temperature and/or high-pressure hydrogen service. Its key applications include: * **Petroleum Refining:** Hydrocracking reactors, hydrotreating reactors, and high-pressure separators. * **Chemical & Petrochemical Plants:** Reactors and vessels exposed to corrosive environments at elevated temperatures. * **Power Generation:** Boiler drums, steam drums, and high-temperature pressure parts in fossil fuel power plants. * **Oil & Gas Industry:** Equipment for synthesis gas and ammonia production. **6. Key Characteristics & Advantages** * **High-Temperature Strength:** Maintains structural integrity and creep resistance under sustained loads at high temperatures. * **Hydrogen Resistance:** The chromium and molybdenum content provides good resistance to hydrogen embrittlement and hydrogen attack (as defined by the Nelson Curve in API RP 941). * **Weldability:** It has good weldability, though it requires pre-heating and post-weld heat treatment (PWHT) to prevent cracking and restore the mechanical properties in the heat-affected zone (HAZ). * **Toughness:** The normalized and tempered heat treatment ensures a fine-grained microstructure with adequate toughness. In summary, **ASTM A387 Grade 7 Class 2** is a high-performance, heat-treated chromium-molybdenum alloy steel plate that is an industry standard for critical high-temperature and high-pressure applications in the energy and chemical processing sectors. --- -:- For detailed product information, please contact sales. -: ASTM A387 Alloy Steel, Grade 7, Class 2 Specification Dimensions Size： Diameter 20-1000 mm Length <4375 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 A387 Alloy Steel, Grade 7, Class 2 Properties -:- For detailed product information, please contact sales. -:

Applications of ASTM A387 Alloy Steel Flange, Grade 7, Class 2 -:- For detailed product information, please contact sales. -: Chemical Identifiers ASTM A387 Alloy Steel Flange, Grade 7, Class 2 -:- For detailed product information, please contact sales. -:

Packing of ASTM A387 Alloy Steel Flange, Grade 7, 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 846 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