What factors influence the price of SA387 Grade 12 Class 2?
SA387 Grade 12 Class 2 (also designated as A387 Gr 12 Cl 2) is a high-quality chrome-molybdenum alloy steel plate primarily used for weldable pressure vessels and industrial boilers designed for elevated temperature service.
The price of SA387 Grade 12 Class 2 is influenced by a combination of market, production, and procurement factors specific to this 1Cr-0.5Mo alloy steel plate in the normalized and tempered (N+T) condition. Below are the key determinants:
1. Market & Raw Material Factors
Alloy Element Costs: Prices of molybdenum (Mo) and chromium (Cr) directly affect the base cost, though less than for higher-alloy grades like Grade 22. Fluctuations in scrap steel and iron ore also set a baseline.
Sector Demand: Demand from power generation, petrochemical, and boiler manufacturing industries drives competition. Refinery turnaround cycles and energy infrastructure projects heavily influence demand spikes.
Trade Policies: Tariffs, import quotas, or anti-dumping measures in key markets (e.g., U.S., EU, India) can limit supply and increase costs.
2. Product & Manufacturing Factors
Plate Dimensions: Thickness and width are major cost drivers. Thicker plates (>50mm) or extra-wide cuts require more controlled rolling, may involve limited mill capacity, and consume more material.
Heat Treatment (Class 2): The normalizing and tempering (N+T) process adds significant cost due to precise furnace operations, energy consumption, and extended processing time-more so than annealing (Class 1).
Order Quantity: Larger volumes (full mill heats or truckloads) typically secure volume discounts, while small orders or cut pieces incur higher per-unit costs.
Mill Source & Certification: Plates from reputable mills (especially in the EU, Japan, or North America) with full ASTM/ASME certification and traceability command a premium.
3. Procurement & Logistics Factors
Testing & Certification: Standard Mill Test Reports (MTRs) are included. Additional testing-such as ultrasonic examination (UT), impact testing at low temperatures, or third-party inspection-adds cost.
Processing Services: Value-added services like precision cutting, beveling, shot blasting, or priming increase the final price.
Delivery & Location: Freight costs, delivery urgency (ex-stock vs. mill production lead time), and regional logistics challenges impact pricing.
Currency Exchange Rates: Transactions often occur in USD or EUR, so fluctuations affect buyers using other currencies.
Key Differentiators from Other Grades
Class 2 Premium: The N+T heat treatment makes it more expensive than Class 1 (annealed), but provides higher as-supplied strength, reducing the need for extensive post-fabrication heat treatment.
Moderate Alloy Content: Being a 1Cr-0.5Mo steel, it is less sensitive to extreme alloy surcharges than Grades 5 or 22, but more sensitive than carbon steel.
Application Focus: Used in moderate-temperature service (~425–540°C / ~800–1000°F), its demand is tied to general industrial maintenance and mid-range pressure vessel projects.
Summary of Price Influencers
| Category | Specific Factors for SA387 Gr 12 Cl 2 |
|---|---|
| Market | Mo/Cr prices; carbon steel trends; trade policies; demand from power/petrochemical sectors. |
| Product | Plate thickness/width; N+T heat treatment cost; order volume; mill reputation. |
| Quality | Level of testing (standard MTR vs. UT/impact tests); certification requirements. |
| Logistics | Freight/distance; processing services (cutting, beveling); currency rates; stock vs. mill lead time. |
Practical Pricing Scenarios
High-Cost Case: A thick, non-standard width plate ordered in a small quantity from a premium mill, requiring additional impact testing and UT, with urgent ex-stock delivery during a period of high molybdenum prices.
Lower-Cost Case: A standard-thickness plate ordered in bulk from a stockist during stable markets, with only standard MTRs and routine lead time.
Procurement Tips
Specify Clearly: Provide exact dimensions, quantity, testing requirements (e.g., Charpy impact temperature), and delivery schedule.
Compare Total Cost: Include potential savings from reduced post-fabrication heat treatment (vs. Class 1) when evaluating Class 2.
Source Strategically: Consider both mill-direct and reputable distributors, and monitor alloy market trends for optimal timing.
By understanding these factors, buyers can better navigate pricing, optimize specifications, and secure cost-effective procurement for SA387 Grade 12 Class 2.
1.What is SA387 Grade 12 Class 2?
SA387 Grade 12 Class 2 is a chromium-molybdenum alloy steel plate designed for welded pressure vessels, supplied in the normalized and tempered heat-treated condition for improved toughness and strength.
2.What is the difference between SA387 Gr12 Cl 1 and Cl 2?
The key difference is the mandatory heat treatment. Grade 12 Class 2 must be supplied normalized and tempered, while Class 1 can be supplied as-rolled, annealed, or normalized and tempered, affecting its mechanical properties.
3.What is the chemical composition of SA387 Grade 12 Class 2?
Its typical composition includes Chromium (0.80-1.25%), Molybdenum (0.44-0.65%), Carbon (max 0.17%), Manganese (0.40-0.65%), Silicon (0.15-0.40%), and limited Phosphorus and Sulfur.
4.What are the mechanical properties of SA387 Gr12 Cl 2?
Key properties include a minimum tensile strength of 485 MPa (70 ksi) and a minimum yield strength of 275 MPa (40 ksi) for thicknesses up to 65mm, with higher strength than Class 1.
5.What is SA387 Gr12 Cl 2 equivalent to?
It is equivalent to ASTM A387 Gr12 Cl 2, ASME SA387 Gr12 Cl 2, and the common material grade UNS K11757. It is similar to 1.25%Cr-0.5%Mo steel.
6.What is the heat treatment for SA387 Grade 12 Class 2?
Per the specification, SA387 Grade 12 Class 2 plates are supplied in the normalized (heated above the critical temperature and air-cooled) and subsequently tempered (reheated to a specific sub-critical temperature) condition.
7.Why choose Class 2 over Class 1 for SA387 Grade 12?
Class 2 is chosen when the application requires guaranteed higher strength, better microstructural uniformity, and improved notch toughness due to its mandatory normalized and tempered condition.
8.What is the maximum operating temperature for SA387 Gr12 Cl 2?
It is commonly used for service temperatures up to approximately 800-850°F (427-454°C), particularly in hydrogen service and other high-temperature refinery applications.
9.How to weld SA387 Grade 12 Class 2 steel?
Welding requires preheating (typically 250-400°F / 121-204°C) and a mandatory post-weld heat treatment (PWHT). Common filler metals include AWS E8018-B2 for SMAW or equivalent.
10.What is the hardness of SA387 Grade 12 Class 2?
Hardness is not directly specified in the standard but is controlled by the heat treatment and mechanical properties. For service in wet H2S environments, it is often specified to be below 200 HB or 22 HRC to resist sulfide stress cracking.
Full specification and details are available on request. The above information is provided for guidance purposes only. For specific design requirements please contact our technical sales staff.
