ASTM A387 Alloy Steel Wire, Grade 7, Class 1

ASTM A387 Alloy Steel Wire, Grade 7, Class 1 Product Information -:- For detailed product information, please contact sales. -: ASTM A387 Alloy Steel Wire, Grade 7, Class 1 Synonyms -:- For detailed product information, please contact sales. -:

ASTM A387 Alloy Steel, Grade 7, Class 1 Product Information -:- For detailed product information, please contact sales. -: ### **Product Introduction: ASTM A387 Grade 7 Class 1 Steel** **ASTM A387 Grade 7 Class 1** is a chromium-molybdenum alloy steel plate designed for pressure vessel applications requiring excellent elevated temperature strength and superior corrosion resistance. This specification covers plates in the annealed or normalized and tempered condition, suitable for welded pressure vessels operating in severe high-temperature environments. --- #### **1. International Standards & Classification** **Primary Standard:** **ASTM A387/A387M** - "Standard Specification for Pressure Vessel Plates, Alloy Steel, Chromium-Molybdenum" **Grade Classification:** - **Grade 7** - 7.0% Chromium - 0.5% Molybdenum alloy steel - **Class 1** - Annealed or normalized and tempered condition **International Equivalents:** - **EN 10028-2**: X12CrMo7 - **JIS G4109**: SCMV 9 - **GB/T 3077**: 50Cr7MoSiV - **ISO 9328-2**: X12CrMo7 --- #### **2. Chemical Composition** The chemical composition requirements for ASTM A387 Grade 7: | Element | Composition (Maximum %) | |---|---| | Carbon (C) | 0.15 | | Manganese (Mn) | 0.30-0.60 | | Phosphorus (P) | 0.035 | | Sulfur (S) | 0.035 | | Silicon (Si) | 0.50-1.00 | | Chromium (Cr) | 6.00-8.00 | | Molybdenum (Mo) | 0.45-0.65 | **Key Composition Features:** - **High Chromium Content**: 6.00-8.00% for exceptional oxidation and corrosion resistance - **Molybdenum Addition**: 0.45-0.65% for enhanced creep strength - **Controlled Carbon**: Maximum 0.15% for weldability and toughness - **Silicon Enhancement**: 0.50-1.00% for improved high-temperature strength --- #### **3. Physical & Mechanical Properties** **Mechanical Properties (Class 1 condition):** | Property | Value | |---|---| | **Tensile Strength** | 515-690 MPa (75-100 ksi) | | **Yield Strength (min.)** | 310 MPa (45 ksi) | | **Elongation in 2" (min.)** | 18% | | **Elongation in 8" (min.)** | 20% | **Elevated Temperature Properties:** - **Maximum Service Temperature**: Up to 700°C (1290°F) - **Creep Strength**: Excellent resistance to creep deformation - **Oxidation Resistance**: Superior performance in high-temperature oxidizing atmospheres - **Sulfidation Resistance**: Outstanding resistance to sulfur attack **Physical Properties:** - **Density**: 7.75 g/cm³ (0.280 lb/in³) - **Modulus of Elasticity**: 205 GPa (29,700 ksi) - **Thermal Conductivity**: 32.5 W/m·K - **Coefficient of Thermal Expansion**: 10.8 × 10⁻⁶/°C - **Specific Heat Capacity**: 450 J/kg·K --- #### **4. Product Applications** **High-Temperature Pressure Vessels:** - Hydrocracking reactors - Catalytic reforming units - High-temperature hydrogen vessels - Severe service refinery equipment **Power Generation:** - High-temperature boiler components - Steam cracking tubes - Advanced heat exchanger systems - High-pressure high-temperature piping **Petrochemical Industry:** - Ethylene production equipment - High-temperature reactors - Petrochemical processing vessels - Refinery conversion units **Special Applications:** - Synthetic fuel processing equipment - High-temperature chemical reactors - Advanced energy systems - High-corrosion service equipment --- #### **5. Fabrication Characteristics** **Welding Performance:** - **Fair Weldability**: Requires careful procedure control - **Preheat Requirements**: 250-350°C (480-660°F) minimum - **Post-Weld Heat Treatment**: Mandatory at 730-760°C (1350-1400°F) - **Recommended Processes**: GTAW, SMAW (low-hydrogen) - **Filler Metals**: E505-XX, E7Cr-XX or equivalent **Forming & Machining:** - **Moderate Formability**: Hot forming required for complex shapes - **Machinability**: Fair (approximately 40% of B1112 steel) - **Cutting Methods**: Plasma and waterjet cutting recommended - **Hot Working Temperature**: 1050-1150°C (1920-2100°F) **Heat Treatment:** - Supplied in annealed or normalized and tempered condition - Normalizing temperature: 950-980°C (1740-1800°F) - Tempering temperature: 700-750°C (1290-1380°F) - Annealing temperature: 850-880°C (1560-1615°F) **Quality Assurance:** - **Comprehensive Testing**: Full mechanical and chemical analysis - **Impact Testing**: Required for pressure vessel applications - **Hardness Testing**: Mandatory quality control - **Non-Destructive Testing**: UT, RT, MT as specified --- ### **Technical Summary** ASTM A387 Grade 7 Class 1 represents an advanced chromium-molybdenum alloy steel offering exceptional high-temperature corrosion resistance and mechanical properties. The 7% chromium content provides outstanding resistance to oxidation, sulfidation, and other high-temperature corrosive environments, making it suitable for the most severe service conditions in refinery and petrochemical applications. This grade demonstrates superior performance in applications involving high-temperature hydrogen service, sulfur-containing atmospheres, and other aggressive corrosive media. The material's enhanced chromium content significantly improves its resistance to high-temperature scaling and corrosive attack compared to lower chromium grades, while the molybdenum addition ensures excellent creep strength and thermal stability. Grade 7 Class 1 is particularly valuable for hydrocracking reactors, catalytic reforming units, and other high-temperature processing equipment where both mechanical integrity and corrosion resistance are critical requirements. The material's ability to withstand temperatures up to 700°C (1290°F) while maintaining good mechanical properties makes it ideal for advanced energy systems and high-temperature chemical processing applications. While requiring sophisticated fabrication techniques and stringent quality controls, ASTM A387 Grade 7 Class 1 delivers reliable performance in the most demanding high-temperature, high-pressure service conditions. Its proven track record in severe service applications has established it as a premium material choice for engineers designing pressure vessels and process equipment for extreme operating environments in the petroleum refining, chemical processing, and power generation industries. -:- For detailed product information, please contact sales. -: ASTM A387 Alloy Steel, Grade 7, Class 1 Specification Dimensions Size： Diameter 20-1000 mm Length <4374 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 1 Properties -:- For detailed product information, please contact sales. -:

Applications of ASTM A387 Alloy Steel Wire, Grade 7, Class 1 -:- For detailed product information, please contact sales. -: Chemical Identifiers ASTM A387 Alloy Steel Wire, Grade 7, Class 1 -:- For detailed product information, please contact sales. -:

Packing of ASTM A387 Alloy Steel Wire, Grade 7, Class 1 -:- 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 Wire 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 845 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