EN S355K2G4 High Manganese, Quality Steel Tube,Pipe

EN S355K2G4 High Manganese, Structural, Hot Rolled, Quality Steel Tube Product Information -:- For detailed product information, please contact sales. -: EN S355K2G4 High Manganese, Structural, Hot Rolled, Quality Steel Tube Synonyms -:- For detailed product information, please contact sales. -:

EN S355K2G4 High Manganese, Structural, Hot Rolled, Quality Steel Product Information -:- For detailed product information, please contact sales. -: # **Product Name:** EN S355K2G4 (S355K2+M) Structural Steel, Thermomechanically Rolled, High-Toughness Grade **Overview** EN S355K2G4 is a **premium thermomechanically controlled processed (TMCP), fine-grained structural steel** specified under EN 10025-4. The "K2G4" designation indicates a material with **enhanced guaranteed impact toughness at -20°C (K2 quality)**, supplied in the **thermomechanically rolled condition (G4 or +M)**. This grade represents the optimal synergy of modern metallurgy and processing, delivering an exceptional combination of high strength, superior fracture resistance at low temperatures, and excellent weldability without a separate heat treatment. It is specifically designed for the most critical welded structures where weight optimization, fabrication efficiency, and uncompromising safety in cold environments are paramount. It is **not a "High Manganese" steel**; its properties are achieved through advanced TMCP technology, microalloying, and grain refinement. **Key International Standards** * **Primary Standard:** **EN 10025-4:2019** - Hot rolled products of structural steels - Part 4: Technical delivery conditions for thermomechanical rolled weldable fine grain structural steels. * **Grade & Condition Designation:** **S355K2G4** or **S355K2+M** * **S:** Structural Steel. * **355:** Minimum yield strength (ReH) in MPa for thicknesses **≤ 16 mm**. * **K2:** **Superior quality designation.** Guarantees a higher minimum impact energy at **-20°C** compared to the standard J2 grade. * **G4/M:** Indicates **thermomechanical rolling (TMCP, M)**. * **Key Distinction:** The "K2" quality is the **toughest standard quality** within the EN 10025 series for -20°C service, requiring a higher absorbed impact energy. Combined with the benefits of TMCP (low CEV), it offers a best-in-class balance for critical applications. * **Common International Equivalents:** * **ASTM:** **A841 Grade B** (TMCP plate) with supplemental toughness requirements. * **GB/T:** **Q355D/E** (TMCP variants). * **Specialized:** Fully compliant with demanding specifications such as **EN 10225** for offshore structures and various **national bridge standards**. **Chemical Composition (Ladle Analysis, % by weight, typical for high-toughness TMCP steel)** Lean, clean chemistry optimized for TMCP response and maximum toughness. * **Carbon (C):** **Low, typically ≤ 0.10%** (Essential for low CEV and high toughness). * **Manganese (Mn):** **1.40% - 1.60%** (Balanced for strength with minimal CEV impact). * **Phosphorus (P):** ≤ **0.020%** (Very low). * **Sulphur (S):** ≤ **0.005%** (Extremely low, often calcium-treated for inclusion shape control). * **Silicon (Si):** ≤ **0.40%**. * **Aluminum (Alt):** ≥ **0.020%** (For grain refinement). * **Microalloys (Nb, Ti, V):** Precisely added (e.g., Nb 0.02-0.05%, Ti 0.01-0.02%) to control austenite conditioning and precipitation during TMCP. * **Carbon Equivalent (CEV):** **Very low, typically ≤ 0.36**. This is a **fundamental advantage**, drastically improving weldability by reducing pre-heat requirements and hydrogen cracking sensitivity. **Physical & Mechanical Properties (for thermomechanical condition, thickness ≤ 16mm)** * **Yield Strength (ReH):** ≥ **355 MPa** (Minimum for t ≤ 16mm; thickness-dependent). * **Tensile Strength (Rm):** **470 - 630 MPa**. * **Elongation at Break (A5):** ≥ **21%** (Minimum, typically higher). * **Impact Energy (KV):** **≥ 40 J at -20°C** (Longitudinal, Charpy V-notch). **This is the defining K2 property (≥40J), superior to the 27J of J2 grades.** Actual values often exceed 60J. * **Fine Grain Size:** Extremely fine, typically **ASTM 10 or finer**. * **Yield-to-Tensile Ratio:** Typically <0.85, indicating good plastic deformation capacity. * **Density:** **~7.85 g/cm³**. * **Modulus of Elasticity:** **210 GPa**. **Product Features** 1. **Superior Fracture Toughness (K2 Quality):** Provides the highest standard-guaranteed impact energy at -20°C within the S355 TMCP family, offering an extra safety margin against brittle fracture for critical components. 2. **Excellent Weldability (Key Feature):** The **very low carbon equivalent (CEV)** allows for welding with **significantly lower or no pre-heat**, simplifies procedure qualification, reduces fabrication time and cost, and minimizes the risk of hydrogen-induced cold cracking—a major advantage for on-site construction. 3. **TMCP Efficiency:** Achieves this high level of strength and toughness in-line during rolling, eliminating the energy consumption of normalizing. 4. **Homogeneous, Fine-Grained Structure:** The controlled process results in a very uniform microstructure with excellent through-thickness properties. **Typical Applications** S355K2G4 is the material of choice for modern, high-integrity structures in demanding environments. * **Offshore Wind & Oil & Gas:** **Monopile transitions, jacket nodes, floating platform components**—where weldability and toughness are critical for fatigue life and safety. * **Critical Bridge Construction:** **Welded box girders, orthotropic decks, and splice plates** for major bridges in cold climates or seismic zones. * **Shipbuilding (High-Value Vessels):** **Ice-class hull structures, liquefied gas carrier support systems**. * **Heavy Mobile Equipment:** **Critical welded frames and booms** for cranes and excavators operating in Arctic conditions. * **Building Construction:** **Seismic moment-resisting frames and diagrid nodes** in high-rise buildings. **Available Forms & Processing** * **Forms:** Primarily supplied as **thermomechanically rolled plates**. Available in wider thickness ranges than normalized grades. * **Surface:** With standard mill scale. Often supplied as shot blasted and primed for critical projects. * **Processing:** Excellent for all cutting and welding. **Medium-low heat input welding processes are recommended** to preserve the fine-grained HAZ microstructure. Good cold forming capability. --- **Critical Procurement Note** * **Specify Correct Standard:** Ensure reference to **EN 10025-4**. The "K2" quality is specific to fine-grained steels (Parts 3 & 4). * **Thickness-Dependent Strength:** Use the correct guaranteed yield strength from EN 10025-4 tables for the product thickness. * **Explicit Toughness Requirement:** Ordering "K2" explicitly demands the higher impact value (≥40J). This is not the default; S355J2G4 is the standard TMCP grade. * **Welding Advantage:** The low CEV should be actively leveraged in fabrication planning to optimize costs and schedules. * **Not "High Manganese":** This term is incorrect. The correct classification is **"Thermomechanically Rolled Fine Grain Structural Steel with Enhanced -20°C Toughness (K2 Quality)."** * **Certification:** Supplied with a full **Inspection Certificate 3.1/3.2**, including chemistry (noting low CEV), mechanical properties, and impact tests **at -20°C verifying the ≥40J K2 requirement**. Supplementary through-thickness (Z) testing is common for thick plate. -:- For detailed product information, please contact sales. -: EN S355K2G4 High Manganese, Structural, Hot Rolled, Quality Steel Specification Dimensions Size： Diameter 20-1000 mm Length <5840 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. -: EN S355K2G4 High Manganese, Structural, Hot Rolled, Quality Steel Properties -:- For detailed product information, please contact sales. -:

Applications of EN S355K2G4 High Manganese, Structural, Hot Rolled, Quality Steel Tube -:- For detailed product information, please contact sales. -: Chemical Identifiers EN S355K2G4 High Manganese, Structural, Hot Rolled, Quality Steel Tube -:- For detailed product information, please contact sales. -:

Packing of EN S355K2G4 High Manganese, Structural, Hot Rolled, Quality Steel Tube -:- 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 Tube 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 2311 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