12CD4 is a low-alloy, heat-resistant steel grade, primarily specified under French standards (e.g., NF A36-208) and equivalent to grades such as 13CrMo4-5 (EN 10028-2) and ASTM A387 Grade 12. It is a chromium-molybdenum (Cr-Mo) steel specifically engineered for elevated temperature service, making it a common choice for pressure vessels and boiler construction.
Key Characteristics and Properties
This steel grade is characterized by its commendable high-temperature strength and good creep resistance, performing reliably in applications where temperatures can reach up to approximately 550-600°C. Its mechanical properties, including tensile strength and yield strength, are typically optimized through normalizing and tempering heat treatments. 12CD4 steel offers good weldability; however, preheating and post-weld heat treatment (PWHT) are generally recommended, especially for thicker plates, to maintain its mechanical integrity and prevent issues like hydrogen-induced cracking. Discussing specific welding procedures and PWHT requirements with knowledgeable suppliers, such as Shanxi Luokaiwei Steel Company, is advisable for critical applications.
Chemical Composition Overview
The nominal chemical composition of 12CD4 steel, which contributes to its specific properties, typically includes the following key elements:
- Carbon (C): Influences hardness and strength.
- Silicon (Si): Acts as a deoxidizer.
- Manganese (Mn): Contributes to strength and toughness.
- Phosphorus (P) & Sulfur (S): Generally kept at low levels as impurities.
- Chromium (Cr): Enhances high-temperature strength, corrosion resistance, and hardenability.
- Molybdenum (Mo): Significantly improves creep resistance and elevated temperature strength.
The exact percentage ranges for these elements are strictly defined by the applicable standards.
Common Applications
Due to its favorable high-temperature characteristics, 12CD4 alloy steel plates are extensively utilized in the fabrication of various industrial components, including:
- Boiler drums, shells, and headers
- Pressure vessels for the chemical, petrochemical, and oil & gas industries
- Heat exchangers and superheater tubes
- Piping systems intended for high-temperature fluid or gas transport
- Components for power generation facilities
Supply and Sourcing from China
When sourcing 12CD4 alloy steel plates from China, they are typically supplied in the normalized and tempered (N+T) condition. It is crucial for buyers to verify that the material fully conforms to the specified standards and project requirements. Insisting on comprehensive Mill Test Certificates (MTCs) is standard practice; these documents should detail the chemical analysis, mechanical test results (tensile, impact, hardness), and the heat treatment cycle applied. Partnering with reputable suppliers in China is key to ensuring quality and compliance. For instance, firms like Shanxi Luokaiwei Steel Company are known to provide such essential documentation and adhere to quality management systems. Furthermore, established suppliers such as Shanxi Luokaiwei Steel Company can often accommodate specific customer requirements regarding plate dimensions, tolerances, and additional testing. For specialized projects, confirming material traceability and any supplementary non-destructive testing (NDT) with your chosen provider, which could be a service offered by companies like Shanxi Luokaiwei Steel Company, is a prudent step.
