ASTM A738 Carbon 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 A738 Carbon Steel Flange, Grade B Product Information -:- For detailed product information, please contact sales. -: ASTM A738 Carbon Steel Flange, Grade B Synonyms -:- For detailed product information, please contact sales. -:

ASTM A738 Carbon Steel, Grade B Product Information -:- For detailed product information, please contact sales. -: # **Product Introduction: ASTM A738 Grade B Carbon-Manganese-Silicon Steel for Low-Temperature Pressure Vessels** **ASTM A738 Grade B** is a **heat-treated carbon-manganese-silicon steel plate** engineered for **welded pressure vessels requiring enhanced strength and guaranteed notch toughness at low temperatures**. As a higher-strength grade within the A738 specification, it provides a **minimum yield strength of 60 ksi (415 MPa)** with mandatory impact toughness testing. This grade is supplied exclusively in the **normalized and tempered or quenched and tempered condition**, ensuring a refined, uniform microstructure capable of withstanding the combined stresses of pressure loading and low-temperature operation. The steel's balanced chemistry and controlled heat treatment make it a reliable choice for critical containment applications where brittle fracture prevention is paramount. --- ## **International Standard & Key Specifications** * **Primary Standard:** **ASTM A738/A738M** - Standard Specification for Pressure Vessel Plates, Heat-Treated, Carbon-Manganese-Silicon Steel, for Moderate and Lower Temperature Service. * **Key Characteristic:** **Mandatory heat treatment** distinguishes this specification from conventional carbon steel plates, ensuring consistent through-thickness properties. * **ASME Code Equivalent:** **SA-738/SA-738M** in ASME Boiler and Pressure Vessel Code, Section II, Part A. Required for ASME-stamped pressure equipment. * **Governing Standard:** **ASTM A20/A20M** - Standard Specification for General Requirements for Steel Plates for Pressure Vessels. * **Impact Test Mandate:** All plates must undergo **Charpy V-notch impact testing** at specified temperatures, with defined minimum energy absorption requirements. --- ## **Chemical Composition (Weight %, max unless range is specified)** The composition is optimized to achieve higher strength while maintaining good weldability and response to heat treatment. | Element | Composition (%) | Role in Performance | | :--- | :--- | :--- | | **Carbon (C)** | 0.27 max | Higher than Grade A to enhance strength; controlled to maintain weldability. | | **Manganese (Mn)** | 1.00 - 1.60 | Primary strengthener; increased range improves hardenability for higher strength. | | **Phosphorus (P)** | 0.035 max | Impurity, minimized for optimal notch toughness. | | **Sulfur (S)** | 0.040 max | Impurity, controlled to ensure good weldability and ductility. | | **Silicon (Si)** | 0.15 - 0.40 | Deoxidizer and solid solution strengthener. | | **Nickel (Ni)** | **0.40 max (optional)** | May be added by agreement to significantly enhance low-temperature toughness. | | **Copper (Cu)** | 0.35 max | Residual element, typically present. | | **Vanadium (V)** | 0.05 max | May be present for grain refinement. | | **Carbon Equivalent (CE)** | Typically ≤ 0.48 | Calculated to ensure adequate weldability despite higher carbon content. | **Key Distinction:** Higher carbon and manganese limits compared to Grade A enable the increased strength level while the optional nickel addition can be utilized for demanding low-temperature applications. --- ## **Typical Physical & Mechanical Properties** Properties are guaranteed after the specified heat treatment (normalized and tempered or quenched and tempered). | 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:** **-50°F (-45°C)**. **Minimum Avg. for 3 Specimens:** **20 ft·lbf (27 J)**. **Minimum Single Value:** 15 ft·lbf (20 J). | | **Brinell Hardness (typical)** | 190 - 240 HBW | | **Design Advantage:** Approximately 20% higher allowable stress values compared to Grade A in ASME Code applications. | --- ## **Product Applications** ASTM A738 Grade B is specified for pressure vessels operating under conditions where both higher design pressures and low-temperature toughness are required, enabling more efficient, thinner-walled designs. **Primary Industries and Equipment:** 1. **Gas Processing & Petrochemical:** * **Low-Temperature Separators** and **Scrubbers** in natural gas processing. * **Ammonia and Urea Process Vessels**. * **LPG Storage Tanks** with higher design pressures. 2. **Power Generation:** * **High-Pressure Feedwater Heaters**. * **Moisture Separator Reheaters (MSRs)**. * **Hydrogen Cooler Shells** in turbine systems. 3. **Cryogenic & Refrigeration:** * **Liquid Carbon Dioxide Storage Vessels**. * **Industrial Refrigeration System Pressure Vessels**. * **Process Equipment** for chemical plants with low-temperature cycles. 4. **Industrial Manufacturing:** * **High-Pressure Accumulators**. * **Custom Fabricated Pressure Vessels** for specialized processes. * **Heat Exchangers** for services combining pressure and low temperature. --- ## **Advantages and Critical Fabrication Considerations** * **Advantages:** * **Higher Strength with Guaranteed Toughness:** 60 ksi yield strength with mandatory impact testing provides reliable performance envelope. * **Material Efficiency:** Higher strength allows for thinner wall sections, reducing weight and material costs. * **Heat Treatment Consistency:** Normalized and tempered or quenched and tempered condition ensures uniform properties. * **Code Compliance:** Fully compliant with ASME Section VIII, Division 1 and 2 requirements for pressure vessels. * **Critical Fabrication & Welding Considerations:** * **Carbon Equivalent Management:** Higher CE requires careful welding procedure development. **Low-hydrogen processes are mandatory.** * **Preheat Requirements:** More stringent than Grade A, especially for thicker sections. Typical range: 200-300°F (95-150°C). * **Post-Weld Heat Treatment (PWHT):** Generally required for pressure vessel fabrication. PWHT temperature must be controlled to avoid overtempering the base metal. * **Welding Consumable Selection:** Filler metals should match or slightly undermatch the base metal strength to ensure weld metal toughness. * **Impact Test Verification:** Welding Procedure Specifications (WPS) should be qualified with impact testing of weld metal and HAZ when service temperatures are low. * **Thermal Cutting Precautions:** Preheating before flame cutting is recommended to prevent hydrogen cracking. * **Thickness Limitations:** As thickness increases, achieving both strength and toughness becomes more challenging; properties should be verified for specific thickness ranges. **In summary, ASTM A738 Grade B is a heat-treated carbon steel plate offering a 60 ksi minimum yield strength with guaranteed impact toughness at -50°F. Its enhanced strength-to-weight ratio makes it particularly suitable for pressure vessel designs where weight reduction and higher pressure capabilities are important, while its mandatory heat treatment and impact testing ensure reliable performance in low-temperature service. This grade represents an optimal balance between performance and cost for demanding pressure vessel applications across multiple industries.** -:- For detailed product information, please contact sales. -: ASTM A738 Carbon Steel, Grade B Specification Dimensions Size： Diameter 20-1000 mm Length <4535 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 A738 Carbon Steel, Grade B Properties -:- For detailed product information, please contact sales. -:

Applications of ASTM A738 Carbon Steel Flange, Grade B -:- For detailed product information, please contact sales. -: Chemical Identifiers ASTM A738 Carbon Steel Flange, Grade B -:- For detailed product information, please contact sales. -:

Packing of ASTM A738 Carbon 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 1006 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