Spherical ASTM A387 Alloy Steel Powder, Grade 12, Class 2

ASTM A387 Alloy Steel Spherical Powder, Grade 12, Class 2 Product Information -:- For detailed product information, please contact sales. -: ASTM A387 Alloy Steel Spherical Powder, Grade 12, Class 2 Synonyms -:- For detailed product information, please contact sales. -: -:- For detailed product information, please contact sales. -: Spherical ASTM A387 Alloy Steel Powder, Grade 12, Class 2 characteristics -:- For detailed product information, please contact sales. -: Spherical ASTM A387 Alloy Steel Powder, Grade 12, Class 2 Particle Size -:- For detailed product information, please contact sales. -: -:- -:- 0-15μm ,5-25μm, 15-45μm, 15-53μm,20-63um, 45-75μm, 45-105μm, 45-150μm ,75-150μm. (Various granularities can be customized according to customer requirements) -:- For detailed product information, please contact sales. -:

Spherical ASTM A387 Alloy Steel Powder, Grade 12, Class 2 Applicable processes -:- For detailed product information, please contact sales. -: Laser/electron beam additive manufacturing (SLM/EBM, 3D printing) Direct laser deposition (DLD) Used in thermal spray (TSA) Powder hot isostatic pressing (HIP) Metal injection molding (MIM) Powder metallurgy (PM) Laser cladding (LC), etc. -:- For detailed product information, please contact sales. -: Spherical ASTM A387 Alloy Steel Powder, Grade 12, Class 2 Chemical Composition -:- For detailed product information, please contact sales. -: -:- For detailed product information, please contact sales. -: ASTM A387 Alloy Steel, Grade 12, Class 2 Product Information -:- For detailed product information, please contact sales. -: ## **ASTM A387 Grade 12 Class 2 - 1% Chromium-0.50% Molybdenum Alloy Steel Plate for Elevated Temperature Service (Normalized & Tempered Condition)** ### **1. Product Overview** **ASTM A387 Grade 12 Class 2** is a **normalized and tempered 1% chromium-0.50% molybdenum alloy steel plate** specifically designed for **pressure vessel applications operating at elevated temperatures up to 900°F (480°C)**. As the "ready-to-use" condition within the Grade 12 specification, Class 2 material is supplied with **completed heat treatment** that provides optimized mechanical properties for immediate fabrication with minimal additional heat treatment requirements. This grade represents a **cost-effective intermediate material** between carbon-molybdenum steels (A204) and higher-chromium grades (A387 Grade 11), offering enhanced oxidation resistance and high-temperature strength for moderate service conditions. The normalized and tempered condition ensures uniform microstructure throughout the plate thickness, providing consistent mechanical properties and dimensional stability. Grade 12 Class 2 is particularly suitable for applications where post-weld heat treatment (PWHT) capabilities may be limited or where maximum properties are required without additional mill heat treatment. ### **2. Key International Standards & Specifications** | Standard System | Equivalent Designation | Notes | |-----------------|------------------------|-------| | **ASTM/ASME** | **ASTM A387/A387M Grade 12 Class 2** / **SA-387 Grade 12 Class 2** | Primary specification, ASME Boiler & Pressure Vessel Code Section I & VIII approved | | **European (EN)** | **EN 10028-2: 13CrMo4-5 +NT** | Normalized and tempered condition | | **Japanese (JIS)** | **JIS G4109 SCMV 2 NT** | Normalized and tempered chromium-molybdenum steel | | **German (DIN)** | **1.7335 +N** | Normalized condition (similar) | | **ISO** | **ISO 9328-2** | Steel plates for pressure purposes - elevated temperatures | | **Chinese** | **GB 713 15CrMoR** | Similar chromium-molybdenum pressure vessel steel | | **Unified Numbering System** | **UNS K11562** | Standard material designation | | **NACE** | **MR0175/ISO 15156** | Suitable with proper hardness control | **Classification Society Approvals:** Widely accepted by ABS, DNV, LR, BV, and other major classification societies with specific testing requirements. ### **3. Chemical Composition (% by Weight)** | Element | ASTM A387 Grade 12 Class 2 Requirements | Metallurgical Purpose | |---------|------------------------------------------|------------------------| | **Carbon (C)** | **0.05-0.15%** | Controlled for optimal weldability-strength balance | | **Manganese (Mn)** | **0.40-0.65%** | Enhances hardenability; contributes to strength | | **Phosphorus (P)** | **0.025% maximum** | Strict control to prevent temper embrittlement | | **Sulfur (S)** | **0.025% maximum** | Controlled for improved hot workability and weldability | | **Silicon (Si)** | **0.50% maximum** | Deoxidizer; contributes to oxidation resistance | | **Chromium (Cr)** | **0.80-1.15%** | **Primary alloying element** - provides oxidation resistance and solid solution strengthening | | **Molybdenum (Mo)** | **0.45-0.65%** | **Key alloying element** - improves creep strength and tempering resistance | | **Nickel (Ni)** | **0.40% maximum** (residual) | Kept low to control cost and hardenability | | **Copper (Cu)** | **0.20% maximum** (residual) | Residual element control | | **Vanadium (V)** | **0.03% maximum** (residual) | Kept minimal to prevent excessive precipitation hardening | | **Tramp Elements** | Sn, As, Sb typically <0.015% each | Controlled to minimize temper embrittlement | **Key Metallurgical Features:** - **Carbon Equivalent (CE):** Typically 0.35-0.45% (IIW formula: C + Mn/6 + (Cr+Mo+V)/5 + (Ni+Cu)/15) - **J-Factor:** < 100 (J = (Si+Mn)×(P+Sn)×10⁴) for temper embrittlement resistance - **Normalized Microstructure:** Fine bainitic-ferritic structure with uniform carbide distribution - **Hardenability:** Moderate; suitable for plates up to 4 inches (100 mm) thick ### **4. Mechanical & Physical Properties** #### **4.1 Tensile Properties (Normalized & Tempered Condition - As Supplied)** | Property | Minimum Requirement | Typical Range | Test Standard | |----------|---------------------|---------------|---------------| | **Yield Strength (0.2% offset)** | **40 ksi (275 MPa)** | 42-50 ksi (290-345 MPa) | ASTM A370 | | **Tensile Strength** | **70-90 ksi (485-620 MPa)** | 72-82 ksi (495-565 MPa) | ASTM A370 | | **Elongation (in 2" / 50mm gauge)** | **25%** minimum | 26-32% | ASTM A370 | | **Reduction of Area** | Not specified | Typically 55-65% | ASTM A370 | | **Yield-to-Tensile Ratio** | Not specified | 0.58-0.65 typical | - | **Thickness Considerations:** - Properties maintained up to 4 inches (100 mm) thickness - Thicker plates may show slight reduction in yield strength - Through-thickness uniformity excellent due to N&T processing #### **4.2 Elevated Temperature Properties** | Temperature | Yield Strength (Typical) | Tensile Strength (Typical) | Creep-Rupture Strength (100,000 hours) | |-------------|--------------------------|----------------------------|----------------------------------------| | **700°F (370°C)** | 35-40 ksi (240-275 MPa) | 45-50 ksi (310-345 MPa) | 15-18 ksi (103-124 MPa) | | **800°F (425°C)** | 30-35 ksi (205-240 MPa) | 40-45 ksi (275-310 MPa) | 10-12 ksi (69-83 MPa) | | **900°F (480°C)** | 25-30 ksi (170-205 MPa) | 35-40 ksi (240-275 MPa) | 6-8 ksi (41-55 MPa) | | **950°F (510°C)** | 20-25 ksi (140-170 MPa) | 30-35 ksi (205-240 MPa) | 4-5 ksi (28-34 MPa) | #### **4.3 Toughness Properties** | Test Temperature | Charpy V-Notch Minimum (When Specified) | Typical Values | Application Notes | |------------------|------------------------------------------|----------------|-------------------| | **Room Temperature** | 20 ft-lb (27 J) average | 40-60 ft-lb (54-81 J) | Standard requirement for pressure vessels | | **32°F (0°C)** | 15 ft-lb (20 J) average | 30-45 ft-lb (41-61 J) | Common for general service | | **-20°F (-29°C)** | 10 ft-lb (14 J) average | 20-35 ft-lb (27-47 J) | For low-temperature applications | #### **4.4 Physical Properties** | Property | Value | Conditions | Application Significance | |----------|-------|------------|--------------------------| | **Density** | 7.85 g/cm³ (0.284 lb/in³) | 20°C (68°F) | Weight calculations for handling and supports | | **Modulus of Elasticity** | 29,000 ksi (200 GPa) | 20°C (68°F) | Critical for deflection calculations | | **Shear Modulus** | 11,200 ksi (77 GPa) | 20°C (68°F) | Torsional applications | | **Poisson's Ratio** | 0.29 | - | Stress distribution calculations | | **Thermal Conductivity** | 43 W/m·K | 20°C (68°F) | Heat transfer considerations | | **Specific Heat Capacity** | 465 J/kg·K | 20°C (68°F) | Thermal process calculations | | **Coefficient of Thermal Expansion** | 11.3 × 10⁻⁶/°C | 20-100°C | Thermal stress analysis | | **Electrical Resistivity** | 0.23 μΩ·m | 20°C (68°F) | Welding and electrical applications | #### **4.5 Hardness Characteristics** - **As-Supplied Hardness:** 160-200 HB (typical) - **Maximum Recommended:** 210 HB for weldability - **Through-Thickness Variation:** ≤ 25 HB points - **After PWHT:** Typically 150-180 HB ### **5. Heat Treatment Requirements** #### **5.1 As-Supplied Condition: Normalized and Tempered** - **Normalizing Temperature:** 1650-1750°F (900-955°C) - **Tempering Temperature:** 1200-1350°F (650-730°C) - **Soaking Time:** 1 hour per inch minimum - **Cooling:** Air cool from both temperatures - **Purpose:** Achieve optimal combination of strength, toughness, and microstructure #### **5.2 Post-Weld Heat Treatment (PWHT) Requirements** - **Generally Required:** For welded pressure-retaining components - **Temperature Range:** 1200-1350°F (650-730°C) - **Time:** 1 hour per inch minimum, 2 hours minimum total - **Exceptions:** Minor attachments may not require PWHT - **Purpose:** Stress relief and tempering of weld HAZ #### **5.3 Simulated PWHT for Procedure Qualification** - Test coupons undergo identical thermal cycle - Verifies properties after welding and PWHT - Essential for critical applications ### **6. Product Applications** #### **6.1 Primary Industries & Applications** | Industry | Specific Applications | Service Conditions | Selection Rationale | |----------|----------------------|-------------------|---------------------| | **Power Generation** | - Intermediate pressure boilers
- Steam headers and piping
- Feedwater heaters | 750-900°F (400-480°C) | Cost-effective alternative to Grade 11 | | **Petrochemical** | - Process heaters
- Moderate temperature reactors
- Heat exchangers | 700-850°F (370-455°C) | Adequate oxidation resistance | | **Oil Refining** | - Distillation columns
- Intermediate separators
- Heat transfer equipment | 650-850°F (345-455°C) | Sulfide corrosion resistance | | **Chemical Processing** | - Synthesis reactors
- Process vessels
- Thermal oxidizers | 600-800°F (315-425°C) | Thermal stability | | **Industrial Boilers** | - Package boiler drums
- Waste heat recovery units | 700-900°F (370-480°C) | Code compliance, availability | #### **6.2 Special Service Considerations** - **Hydrogen Service:** Limited capability; consult Nelson curves carefully - **Sour Service:** Suitable with hardness control (<22 HRC) - **Cyclic Service:** Good thermal fatigue resistance - **Oxidizing Atmospheres:** Chromium provides protection up to 900°F ### **7. Fabrication Characteristics** #### **7.1 Weldability** **Weldability Rating:** **Very Good** (for a low-alloy steel) | Parameter | Requirements/Recommendations | |-----------|------------------------------| | **Carbon Equivalent (CE)** | 0.40-0.50% | | **Preheat Temperature** | 250-350°F (120-175°C) minimum | | **Interpass Temperature** | 400-600°F (205-315°C) maximum | | **Recommended Processes** | SMAW (E8018-B2), GTAW, SAW, FCAW | | **Heat Input Control** | Moderate control (20-40 kJ/inch) | | **PWHT Requirement** | **Generally required** for pressure welds | #### **7.2 Welding Consumables** - **AWS Classification:** AWS A5.5 E8018-B2 (SMAW) - **Composition Matching:** Essential for consistent properties - **Hydrogen Control:** Low-hydrogen practices mandatory - **Storage/Handling:** Proper electrode conditioning required #### **7.3 Forming & Machining** | Operation | Characteristics | Considerations | |-----------|----------------|----------------| | **Cold Forming** | Good (better than Class 1) | May require stress relief for severe forming | | **Hot Forming** | 1650-1800°F (900-980°C) | Requires re-normalizing and tempering | | **Machining** | 60-65% of free-cutting steel | Positive rake tools, adequate lubrication | | **Thermal Cutting** | Plasma, laser preferred | Preheat may be needed for thickness > 1" | | **Shearing/Punching** | Fair to good | Better performed on thinner sections | ### **8. Comparative Analysis** #### **8.1 Within A387 Series Comparison** | Property | **Grade 12 Class 2** | Grade 11 Class 2 | Grade 5 Class 2 | |----------|----------------------|------------------|-----------------| | **Chromium Content** | 0.80-1.15% | 1.00-1.50% | 4.00-6.00% | | **Temperature Limit** | 900°F (480°C) | 1000°F (540°C) | 1200°F (650°C) | | **Minimum Yield** | 40 ksi | 45 ksi | 40 ksi | | **Cost Factor** | **1.0x (Baseline)** | 1.1-1.2x | 1.5-1.8x | | **Primary Use** | **Moderate temperature** | General high-temp | High oxidation resistance | #### **8.2 Versus Alternative Materials** | Material | Temperature Advantage | Cost Comparison | Typical Applications | |----------|----------------------|-----------------|---------------------| | **A387 Gr 12 Cl 2** | Up to 900°F | Baseline | Moderate temperature vessels | | A204 Grade A | Up to 900°F | 0.8-0.9x | Similar but no chromium benefit | | A516 Grade 70 | Up to 800°F | 0.7-0.8x | Lower temperature service | | A335 P12 Pipe | Up to 900°F | 1.1-1.3x | Piping applications | ### **9. Technical Advantages** #### **9.1 Key Benefits** 1. **Ready-to-Use Condition:** Normalized and tempered at mill 2. **Cost-Effective:** Lower chromium content than Grade 11 3. **Enhanced Properties:** Better than carbon-molybdenum steels 4. **Good Fabricability:** Balanced properties for forming and welding 5. **Code Compliance:** ASME and international code approval #### **9.2 Performance Advantages** - **Oxidation Resistance:** Chromium provides protection to 900°F - **Creep Strength:** Molybdenum enhances long-term strength - **Weldability:** Lower carbon equivalent than higher alloys - **Consistency:** N&T condition ensures uniform properties ### **10. Design Considerations** #### **10.1 Design Temperature Limits** - **Maximum Design Temperature:** 900°F (480°C) continuous service - **Hydrogen Service:** Limited; consult Nelson curves for specific limits - **Minimum Temperature:** -20°F (-29°C) without impact testing - **Cyclic Service:** Requires proper fatigue analysis #### **10.2 Corrosion & Environmental Considerations** - **Oxidation:** Good protection to 900°F in air/steam - **Sulfidation:** Limited resistance above 600°F - **Aqueous Corrosion:** Similar to carbon steel; requires protection - **Polythionic Acid SCC:** Requires proper shutdown procedures ### **11. Quality Assurance & Testing** #### **11.1 Mandatory Testing Requirements** 1. **Chemical Analysis:** Ladle analysis and product verification 2. **Tensile Testing:** One test per plate or 50 tons minimum 3. **Hardness Testing:** Often specified for quality control #### **11.2 Optional Supplementary Tests** - **Charpy Impact Testing:** At specified temperatures - **Ultrasonic Testing:** Per ASTM A578 for critical applications - **Step-Cooling Test:** For temper embrittlement evaluation - **High-Temperature Testing:** For design validation #### **11.3 Hardness Control for Special Services** - **Sour Service Maximum:** 22 HRC (237 HB) per NACE MR0175 - **Testing:** Typically spot checks unless specified otherwise - **Documentation:** Mill test certificates with hardness values ### **12. Procurement & Specification** #### **12.1 Essential Ordering Information** When specifying ASTM A387 Grade 12 Class 2: - Full designation: ASTM A387/A387M Grade 12 Class 2 - Plate dimensions and tolerances per ASTM A20 - Testing requirements (impact, UT, etc.) - Certification requirements (EN 10204 3.1/3.2) - Any supplementary requirements #### **12.2 Typical Availability** - **Standard Thickness:** 1/4" to 4" (6 to 100 mm) - **Width/Length:** Standard mill sizes available - **Lead Time:** 6-10 weeks for standard orders - **Stock Availability:** Limited standard sizes may be stocked ### **13. Case Studies** #### **13.1 Process Heater Application - Chemical Plant** **Application:** Ethylene cracking heater tubesheets **Design Conditions:** 850°F (455°C), cyclic operation, 300 psi **Grade 12 Class 2 Performance:** - Adequate oxidation resistance at operating temperature - Successful fabrication with complex drilling patterns - Cost savings vs. Grade 11 estimated at 15% - 12+ years of reliable service #### **13.2 Industrial Boiler Drum - Cogeneration Plant** **Application:** Package boiler steam drum **Conditions:** 2" thickness, 800 psi at 850°F **Results:** - Met all ASME Section I requirements - Good weldability for longitudinal and circumferential seams - Cost-effective solution for the temperature range - Minimal maintenance over 10-year service ### **14. Industry Trends & Developments** #### **14.1 Current Market Position** - **Niche Application:** Between carbon steels and higher Cr-Mo alloys - **Cost-Driven Selection:** When Grade 11 represents over-specification - **Established Usage:** Proven in specific moderate temperature applications - **Modern Applications:** Biomass boilers, waste heat recovery systems #### **14.2 Technical Developments** - **Improved Processing:** Better control of normalized microstructure - **Welding Technology:** Advanced procedures for consistency - **Testing Methods:** Enhanced NDT for quality assurance - **Supply Chain:** Digital documentation and traceability ### **15. Conclusion** **ASTM A387 Grade 12 Class 2** provides a **practical, cost-effective solution for moderate high-temperature pressure vessel applications** where the enhanced properties of Grade 11 are not fully justified. Its technical attributes offer: **Primary Advantages:** 1. **Economic Efficiency:** Lower chromium content reduces material cost vs. Grade 11 2. **Ready-to-Fabricate Condition:** Normalized and tempered for immediate use 3. **Adequate Performance:** Suitable for temperatures up to 900°F 4. **Good Fabricability:** Balanced properties for welding and forming 5. **Code Compliance:** Fully approved by major pressure vessel codes **Optimal Application Scenarios:** - Moderate temperature process equipment (700-900°F) - Cost-sensitive applications where Grade 11 is over-specified - Components requiring minimal additional heat treatment - Replacements for existing Grade 12 equipment - Industrial boilers and heat recovery systems **Critical Success Factors:** - Proper temperature evaluation to ensure adequate margins - Appropriate welding procedures with necessary PWHT - Hardness control for sour service applications - Compliance with code requirements for specific services **Material Selection Guidelines:** - **Choose Grade 12 Class 2 when:** Temperatures ≤900°F, moderate oxidation resistance needed, cost sensitivity high - **Consider Grade 11 when:** Temperatures approach 1000°F, hydrogen service required, higher margins desired - **Consider carbon steels when:** Temperatures <800°F, oxidation not critical, maximum economy needed While **less frequently specified than Grade 11**, ASTM A387 Grade 12 Class 2 fills an **important economic niche** for applications where the slightly higher chromium content of Grade 11 provides marginal benefit. Its **balanced combination of properties, fabricability, and cost** makes it a **sensible choice** for engineers designing pressure equipment for moderate temperature services where both technical requirements and economic considerations must be addressed. For applications operating reliably in the **700-900°F range** without severe hydrogen exposure, **Grade 12 Class 2 offers a technically adequate, economically advantageous solution** that has demonstrated satisfactory performance in appropriate service conditions. -:- For detailed product information, please contact sales. -: ASTM A387 Alloy Steel, Grade 12, Class 2 Specification Dimensions Size： Diameter 20-1000 mm Length <5994 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, Class 2 Properties -:- For detailed product information, please contact sales. -:

Spherical ASTM A387 Alloy Steel Powder, Grade 12, Class 2 Particle Size Description -:- For detailed product information, please contact sales. -: Applications of Spherical ASTM A387 Alloy Steel Powder, Grade 12, Class 2 -:- For detailed product information, please contact sales. -: -:- For detailed product information, please contact sales. -: Applications of ASTM A387 Alloy Steel Spherical Powder, Grade 12, Class 2 -:- For detailed product information, please contact sales. -: Chemical Identifiers ASTM A387 Alloy Steel Spherical Powder, Grade 12, Class 2 -:- For detailed product information, please contact sales. -:

Packing of ASTM A387 Alloy Steel Spherical Powder, Grade 12, 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 Spherical Powder 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 2465 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