Large Square Billet 300x300mm Q345B

Large Square Billet 300x300mm Q345B - Image 3

Large Square Billet 300x300mm Q345B

This 300x300mm Q345B large square billet is designed to provide excellent performance in large-scale structural applications. Its specific chemical composition and mechanical properties are carefully balanced to ensure that it can withstand heavy loads and endure various processing operations while maintaining high structural integrity. The large size allows for fewer joints in fabricated structures, enhancing overall strength and durability.

2010 ESTABLISHED

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Product details

The Large Square Billet 300x300mm Q345B is a high-performance low-alloy structural steel designed to meet the most demanding requirements of large-scale infrastructure, heavy machinery, and industrial fabrication. Compliant with GB/T 1591-2008 standards, this 300x300mm square billet combines exceptional strength, dimensional stability, and processability, making it the cornerstone of mega-projects where reliability and structural integrity are non-negotiable.

Parameter	Value	Remarks
Standard	GB/T 1591-2008	Low alloy high-strength structural steel standard
Grade	Q345B	Impact tested at 20℃
Chemical Composition (wt%)
– Carbon (C)	≤0.20	To ensure proper weldability and formability for large-section billets
– Silicon (Si)	≤0.55	Helps in deoxidation and influences the strength and toughness properties
– Manganese (Mn)	≤1.70	Enhances strength and toughness across the thick section
– Phosphorus (P)	≤0.040	Kept at a low level to prevent embrittlement in large billets
– Sulfur (S)	≤0.040	Minimized to reduce the risk of cracking during processing
– Niobium (Nb)	≤0.07	Microalloying element for grain refinement, improving mechanical properties
– Vanadium (V)	≤0.15	Aids in strengthening and enhancing heat resistance in thick sections
– Titanium (Ti)	≤0.20	Helps to improve toughness and structural stability
– Nitrogen (N)	≤0.012	Controlled to avoid issues like porosity and embrittlement
Mechanical Properties
– Yield Strength (ReL)	≥345 MPa	For relevant thickness range applicable to 300x300mm section; adjusted as per standard requirements
– Tensile Strength (Rm)	470 – 630 MPa	Ensures the ability to bear heavy loads in structural applications
– Elongation (A)	≥21%	Provides necessary ductility for fabrication and operation
– Impact Energy (Akv)	≥34 J	At 20℃ (longitudinal specimen), important for resisting sudden impact and maintaining integrity
– Bending Test	180°	Bend diameter: 3a (where ‘a’ represents the side length of the square billet or relevant dimension, here for 300x300mm billet)
Dimensions	300 x 300 mm (square cross-section)	Nominal size; with allowable tolerance ranges as per manufacturing standards
Length	Usually 6 – 12m (customizable)	Standard delivery lengths, can be adjusted according to specific project needs
Surface Quality	Required to be free from cracks, significant surface defects like deep scratches, and excessive oxidation scale	To ensure suitability for further processing steps like forging, rolling, etc.
Delivery Condition	Hot rolled, normalized, or TMCP (Thermo-Mechanical Control Process)	Based on specific requirements for optimizing mechanical properties and fabrication needs
Typical Applications	Structural components for large bridges, heavy industrial machinery frames, large-diameter pipe manufacturing billets, foundation structures for high-rise buildings, and components for large-scale pressure vessels	Ideal for applications demanding large-sized, high-strength steel materials with good workability