As a professional service provider with many years of experience in steel trading, we are committed to providing customers with comprehensive solutions that go beyond the product itself:

Complete Specifications: We offer mainstream thicknesses from 1.5mm to 25.4mm and common widths from 1000mm to 2000mm.

Quality Assurance: We have established long-term strategic partnerships with major steel groups to ensure consistent and reliable quality at the source. Each batch of material comes with a mill's Original Quality Certificate (MTC).

Special Specifications: For non-standard thicknesses and widths, we can quickly coordinate with steel mills for production scheduling or mobilize industry resources to find matching sources.

Price Advantage: With our large annual purchasing volume, we have stronger bargaining power, allowing us to pass on the cost advantages of direct supply from steel mills to our customers. We closely monitor price fluctuations in the steel futures and spot markets to provide customers with the most competitive, real-time quotes.

Precision Flattening/Slitting: Equipped with multiple high-precision flattening and slitting lines, we can provide cut-to-length flat sheets or narrow strips of various sizes and specifications, with precise tolerance control and excellent flatness, effectively reducing customers' secondary processing costs.

Surface Treatment: We offer surface pretreatment services such as pickling and shot blasting to meet the needs of various application scenarios.

Technical Consulting Support: Our experienced team of technical consultants provides customers with professional services such as material selection advice, processing technology consultation, and welding guidance.

1. What is the difference between Q235B hot-rolled coil and SPHC hot-rolled coil?

Q235B is a carbon structural steel (GB/T 700, GB/T 3274) that emphasizes mechanical properties (strength and toughness) and is primarily used for structural and load-bearing components.

SPHC is a designation for high-quality carbon structural steel hot-rolled plates and strip (GB/T 710, GB/T 716, or JIS G 3131). "S" stands for Steel, "P" for Plate, "H" for Hot Rolled, and "C" for Commercial. It focuses more on stamping and forming performance and is primarily used for parts requiring cold forming (such as panels and brackets for automobiles and home appliances). SPHC typically requires higher purity and more stringent surface quality and formability specifications.

2. Can Q235B hot-rolled coil replace Q345B?

It's not a simple substitution! The yield strength of Q345B (≥345MPa) is significantly higher than that of Q235B (≥235MPa), but they have different strength grades. Material strength grades are selected during design based on load and structural requirements. Replacing Q345B with Q235B may result in insufficient structural strength and pose a safety hazard. Conversely, replacing Q235B with Q345B may result in unnecessary cost (unless the design allows and consideration is given to issues such as connection compatibility). Material selection must strictly adhere to the design drawing requirements.

3. Is thickness tolerance important when purchasing Q235B hot-rolled coil?

Very important! Thickness tolerance directly affects the material's actual load-bearing capacity, processing accuracy (such as welding and assembly), and cost (based on weight). The national standard GB/T 3274-2017 specifies tolerance bands for normal precision (PT.A) and higher precision (PT.B) corresponding to different thickness ranges. For applications involving precision structures, strict weight control, or subsequent finishing, PT.B or higher tolerances should be explicitly requested and stated in the inquiry and contract.

4. Does the presence of scale on the surface of hot-rolled coil affect its use?

This depends on the subsequent processes and application:

If pickling, shot blasting, or hot-dip galvanizing/thermal spraying is required, the original scale will be removed during processing and will not affect the final product.

If the coil is used directly in welded structures with extremely high weld quality requirements, or if direct coating is required, residual scale may affect weld penetration, weld quality, or coating adhesion. In these cases, it is recommended to purchase pickled coil or request the supplier to perform surface cleaning (such as shot blasting).

For non-exposed structural components and foundation parts, a slight amount of scale is generally acceptable.