ASTM A204 Low Alloy Steel Flange, Grade B

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 A204 Low Alloy Steel Flange, Grade B Product Information -:- For detailed product information, please contact sales. -: ASTM A204 Low Alloy Steel Flange, Grade B Synonyms -:- For detailed product information, please contact sales. -:

ASTM A204 Low Alloy Steel, Grade B Product Information -:- For detailed product information, please contact sales. -: ### **Product Introduction: ASTM A204 Grade B Steel** **ASTM A204 Grade B** is a molybdenum-alloy steel plate offering enhanced mechanical properties for pressure vessel applications requiring improved performance at elevated temperatures. With increased molybdenum content compared to Grade A, this grade provides superior strength and better creep resistance for more demanding high-temperature service conditions. --- #### **1. International Standards & Grades** **Primary Standard:** **ASTM A204/A204M** - "Standard Specification for Pressure Vessel Plates, Alloy Steel, Molybdenum" **Grade Classification:** - **Grade B** - Enhanced molybdenum alloy steel - Other grades: A, C with varying molybdenum content **International Equivalents:** - **EN 10028-2**: 16Mo3 - **JIS G3109**: SCMV 2 - **GB/T 3077**: 20Mo - **ISO 9328-2**: 16Mo3 --- #### **2. Chemical Composition** The chemical composition requirements for ASTM A204 Grade B: | Element | Composition (Maximum %) | |---|---| | Carbon (C) | 0.20 | | Manganese (Mn) | 0.90 | | Phosphorus (P) | 0.035 | | Sulfur (S) | 0.040 | | Silicon (Si) | 0.30 | | Molybdenum (Mo) | 0.45-0.60 | **Key Composition Features:** - **Optimized Molybdenum**: 0.45-0.60% for improved high-temperature strength - **Controlled Carbon**: Balanced for strength and weldability - **Manganese Content**: Provides solid solution strengthening - **Low Silicon**: Maintains good fabrication characteristics --- #### **3. Physical & Mechanical Properties** **Mechanical Properties (for thicknesses ≤ 50 mm):** | Property | Value | |---|---| | **Tensile Strength** | 485-620 MPa (70-90 ksi) | | **Yield Strength (min.)** | 275 MPa (40 ksi) | | **Elongation in 2" (min.)** | 22% | | **Elongation in 8" (min.)** | 25% | **Elevated Temperature Properties:** - **Maximum Service Temperature**: Up to 455°C (850°F) - **Creep Strength**: Superior to Grade A - **Oxidation Resistance**: Suitable for extended high-temperature service - **Thermal Stability**: Maintains properties at elevated temperatures **Physical Properties:** - **Density**: 7.86 g/cm³ (0.284 lb/in³) - **Modulus of Elasticity**: 200 GPa (29,000 ksi) - **Thermal Conductivity**: 49.0 W/m·K - **Coefficient of Thermal Expansion**: 11.8 × 10⁻⁶/°C - **Specific Heat Capacity**: 475 J/kg·K --- #### **4. Product Applications** **High-Temperature Pressure Vessels:** - Boiler drums for higher pressure service - Superheater components - High-pressure heat exchangers - Process reactors for elevated temperature service **Power Generation Equipment:** - Intermediate pressure steam drums - Power plant piping systems - High-temperature feedwater heaters - Turbine bypass systems **Petrochemical Industry:** - Refinery pressure vessels - High-temperature separators - Process heaters - Catalytic cracker components **Chemical Processing:** - High-temperature reactors - Process columns - Thermal fluid systems - High-pressure synthesis vessels --- #### **5. Fabrication Characteristics** **Welding Performance:** - **Good Weldability**: With proper procedure control - **Preheat Requirements**: 175-225°C (350-450°F) recommended - **Post-Weld Heat Treatment**: Stress relieving at 595-650°C (1100-1200°F) - **Recommended Processes**: SMAW, GMAW, FCAW, SAW - **Filler Metals**: E7018, ER70S-6 or equivalent **Forming & Machining:** - **Good Formability**: Suitable for hot forming operations - **Machinability**: Good (approximately 60% of B1112 steel) - **Cutting Methods**: Plasma, laser, and mechanical cutting - **Heat Treatment Response**: Good response to normalizing and tempering **Heat Treatment:** - Typically supplied in normalized condition - Normalizing temperature: 900-940°C (1650-1725°F) - Optional tempering for specific property requirements **Quality Assurance:** - **Mandatory Testing**: Tensile and chemical analysis - **Impact Testing**: When specified by purchaser - **Non-Destructive Testing**: As required by application - **Certification**: Full traceability and test reports --- ### **Technical Summary** ASTM A204 Grade B represents an enhanced molybdenum-alloy steel solution for pressure vessel applications requiring improved performance at elevated temperatures. With a minimum yield strength of 40 ksi (275 MPa), this grade offers approximately 5% higher strength than Grade A, providing better design efficiency for high-pressure applications. The optimized molybdenum content (0.45-0.60%) delivers reliable performance at temperatures up to 455°C (850°F), making Grade B suitable for more demanding service conditions than Grade A. The enhanced creep strength and thermal stability allow for extended service life in high-temperature applications. This grade maintains good fabrication characteristics while offering improved high-temperature performance. The material's response to standard heat treatments and consistent mechanical properties make it a reliable choice for applications in power generation, petrochemical processing, and high-temperature industrial equipment. The proven service history and cost-effectiveness of ASTM A204 Grade B have established it as a preferred material for engineers designing pressure vessels and high-temperature components where enhanced performance over Grade A is required, but the premium cost of higher alloy steels is not justified by the service conditions. -:- For detailed product information, please contact sales. -: ASTM A204 Low Alloy Steel, Grade B Specification Dimensions Size： Diameter 20-1000 mm Length <4337 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 A204 Low Alloy Steel, Grade B Properties -:- For detailed product information, please contact sales. -:

Applications of ASTM A204 Low Alloy Steel Flange, Grade B -:- For detailed product information, please contact sales. -: Chemical Identifiers ASTM A204 Low Alloy Steel Flange, Grade B -:- For detailed product information, please contact sales. -:

Packing of ASTM A204 Low Alloy Steel Flange, Grade B -:- 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 808 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