ASTM A387 Alloy Steel Flange, grade 12, Chromium Molybdenum

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 12, Chromium Molybdenum Product Information -:- For detailed product information, please contact sales. -: ASTM A387 Alloy Steel Flange, grade 12, Chromium Molybdenum Synonyms -:- For detailed product information, please contact sales. -:

ASTM A387 Alloy Steel, grade 12, Chromium Molybdenum Product Information -:- For detailed product information, please contact sales. -: ## **Product Datasheet: ASTM A387 / ASME SA-387 Grade 12 Alloy Steel Plate** **Product Overview** ASTM A387 Grade 12 is a **chromium-molybdenum (Cr-Mo) alloy steel plate** specifically engineered for **pressure vessels and other welded construction** intended for **elevated temperature service**. This grade, with a nominal composition of 1% chromium and 0.5% molybdenum, offers a balanced combination of strength, creep resistance, oxidation resistance, and hydrogen attack resistance at temperatures up to approximately 1100°F (593°C). It is a fundamental material in the petrochemical, refining, and power generation industries for constructing reactors, heat exchangers, and piping operating under high pressure and heat. The standard defines two classes based on heat treatment condition. **Key International Standards** * **Primary Standard:** **ASTM A387 / A387M** - Standard Specification for Pressure Vessel Plates, Alloy Steel, Chromium-Molybdenum. * **Governing Specification:** This product conforms to the requirements for **Grade 12** within ASTM A387. * **ASME Designation:** **SA-387 Grade 12** - The mandatory ASME Boiler and Pressure Vessel Code (BPVC) designation. * **Heat Treatment Classes:** The grade is subdivided into classes defining the delivery condition: * **Class 1:** Supplied in the **annealed or normalized and tempered** condition (softer, better for forming). * **Class 2:** Supplied in the **normalized and tempered or quenched and tempered** condition (higher strength). * **Related Standards:** Directly comparable to **ASTM A213 T12** for tubing, **ASTM A335 P12** for pipe, and international grades like **DIN 17175 13CrMo44** and **EN 10028-2 13CrMo4-5**. **Chemical Composition (Weight % - ASTM A387 Grade 12 Requirements)** | Element | ASTM A387 Grade 12 Requirement | Typical Range / Aim | | :--- | :--- | :--- | | **Carbon (C)** | 0.05 - 0.17% | 0.10 - 0.15% | | **Manganese (Mn)** | 0.40 - 0.65% | 0.45 - 0.60% | | **Phosphorus (P)** | 0.035% max | ≤ 0.020% | | **Sulfur (S)** | 0.035% max | ≤ 0.015% | | **Silicon (Si)** | 0.15 - 0.40% | 0.20 - 0.35% | | **Chromium (Cr)** | **0.80 - 1.15%** | 0.85 - 1.10% | | **Molybdenum (Mo)** | **0.45 - 0.60%** | 0.45 - 0.60% | | **Carbon Equivalent (C.E. IIW)** | -- | Typically 0.40 - 0.50 | **Physical & Mechanical Properties** *Properties vary depending on the specified Class (1 or 2) and thickness.* | Property | Requirement (Grade 12, Class 2 - Normalized & Tempered) | Typical Performance / Notes | | :--- | :--- | :--- | | **Tensile Strength** | 60 - 85 ksi (415 - 585 MPa) | 65 - 80 ksi (448 - 552 MPa) | | **Yield Strength (0.2% Offset)** | 32 ksi (220 MPa) min | 35 - 45 ksi (241 - 310 MPa) | | **Elongation in 2" (Min)** | 20% (for plates ≤ 3/4") | 20-25% | | **Charpy V-Notch Toughness** | Often specified by purchaser per ASTM A20. | Can achieve good impact values when properly heat-treated. | | **Maximum Recommended Metal Temp.** | -- | **Up to ~1100°F (593°C)** for prolonged service. The chromium provides oxidation resistance, and molybdenum provides creep strength. | | **Key Feature** | **Versatile 1Cr-0.5Mo Alloy Plate:** The industry-standard chromium-molybdenum steel plate for elevated temperature pressure vessels, offering a proven balance of fabricability, strength, and environmental resistance. | **Product Applications** ASTM A387 Grade 12 plate is a cornerstone material for critical high-temperature equipment in energy and process industries. * **Hydroprocessing Reactors:** For hydrocrackers and hydrotreaters in refineries, where resistance to high-temperature hydrogen attack (HTHA) is crucial. * **Catalytic Reformers & Chemical Reactors:** Pressure vessels containing catalysts at elevated temperatures. * **Heat Exchanger & Condenser Shells:** For high-temperature, high-pressure service. * **Power Boiler Drums & Headers:** For high-pressure steam generation. * **Synthesis Gas and Ammonia Converters.** * **High-Temperature Piping and Transition Sections.** **Advantages & Fabrication Notes** * **Critical Welding & Heat Treatment Protocols:** Fabrication of A387 Gr. 12 is specialized and demands strict control: * **Preheat:** Mandatory, typically **350-450°F (177-232°C)**. * **Low-Hydrogen Practice:** Essential (use of AWS E8018-B2 or similar electrodes). * **Post-Weld Heat Treatment (PWHT):** **Always required.** Standard range is **1250-1350°F (677-732°C)**. **Slow cooling through the 1200-800°F (649-427°C) range is critical to prevent reheat cracking.** * **Heat Treatment of Formed Parts:** Hot-formed components must undergo a full normalizing and tempering cycle. * **Resistance to High-Temperature Hydrogen Attack (HTHA):** The chromium and molybdenum content provide good resistance, but its suitability must be verified against **API RP 941 (Nelson Curves)** for the specific partial pressure of hydrogen and temperature. * **Oxidation & Creep Resistance:** Provides significantly better performance than carbon steels at temperatures above 800°F (427°C). * **Formability:** Class 1 material is preferred for severe cold forming. Class 2 material offers higher strength but less formability. * **Code Compliance:** Fully recognized in the **ASME BPVC, Section II, Part D** with published allowable stresses up to 1100°F (593°C). Fabrication must comply with ASME Section VIII, Div. 1 or 2. **Disclaimer:** This datasheet provides general information on **ASTM A387 Grade 12 / SA-387 Grade 12**. Procurement specifications must clearly state the **Grade (12) and Class (1 or 2)**, heat treatment, and all supplementary requirements (impact testing, UT). **Design must use ASME BPVC allowable stresses.** Welding and PWHT procedures **must be qualified per ASME Section IX**. The **risk of reheat cracking is significant**; fabrication plans must include controlled heating/cooling rates. For hydrogen service, a **formal HTHA assessment per API RP 941 is mandatory**. Material selection, fabrication, and inspection must be overseen by engineers and inspectors qualified in Cr-Mo alloy steel technology. -:- For detailed product information, please contact sales. -: ASTM A387 Alloy Steel, grade 12, Chromium Molybdenum Specification Dimensions Size： Diameter 20-1000 mm Length <4699 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 12, Chromium Molybdenum Properties -:- For detailed product information, please contact sales. -:

Applications of ASTM A387 Alloy Steel Flange, grade 12, Chromium Molybdenum -:- For detailed product information, please contact sales. -: Chemical Identifiers ASTM A387 Alloy Steel Flange, grade 12, Chromium Molybdenum -:- For detailed product information, please contact sales. -:

Packing of ASTM A387 Alloy Steel Flange, grade 12, Chromium Molybdenum -:- 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 1170 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