Description
Integrated Steel Mill Supply — Hot rolled Q235B and Q345B plates cut to drawing in our own fabrication workshop, backed by full heat-number traceability from slab to finished component.
Technical Specifications
| Parameter | Value |
|---|---|
| Designation | Q235/Q345 Hot Rolled Steel Plate |
| Product Type | Steel Plate / Sheet / Coils |
| Steel Grade | Q235, Q235B, Q345, Q345B, SS400, S235JR, S355JR, A572 GR.70 |
| Standard | AISI, ASTM, BS, DIN, GB, JIS, EN |
| Thickness | 1mm–200mm |
| Width | 300–1500mm |
| Length | Custom requirement |
| Technique | Hot Rolled |
| Surface Treatment | None (as-supplied) |
| Tolerance | ±1% |
| Processing Service | Bending, Welding, Decoiling, Cutting, Punching |
| Application | Building material / Construction / Pressure vessels |
| Material | Carbon Steel, Alloy Steel |
| Special Use | High-Strength Steel Plate |
Application Suitability
| Industry | Typical Applications |
|---|---|
| Construction & Building | Steel frame structures, column base plates, beam end connections, platform decking |
| Industrial & EPC Projects | Pressure vessel shells, reactor supports, pipe rack structural members |
| Infrastructure | Bridge gusset plates, foundation anchor plates, conveyor support frames |
| Warehouse & Logistics | Portal frame end-plates, mezzanine floor bearers, crane beam stiffeners |
Material Traceability Gaps When Plates and Fabrication Come from Separate Sources
Buying cut plates from a trader who sources raw material elsewhere creates a broken certification chain — and that is where projects fail inspection.
When overseas buyers source steel plates from one supplier and send them to a different workshop for cutting and welding, the mill test certificate often does not follow the material through processing. Heat numbers get mixed, grade markings fade after shot blasting, and the final fabricated component arrives on site without a verifiable link back to the original slab. On EN 1090 and AISC projects, this gap means the inspector cannot confirm whether the Q345B plate in the column base actually matches the MTC submitted during tender. [NEED_CITE: material traceability requirements in EN 1090-2 execution classes]
A Q235B Q345B hot rolled steel plate cutting supplier that controls both the raw material and the fabrication process eliminates this gap entirely — one quality system, one set of weld maps, one point of accountability from slab to shipped component.
Matching Plate Grades to Structural and Pressure Vessel Demands
Hot rolled Q235B and Q345B plates serve fundamentally different structural roles, and selecting the right grade at the inquiry stage prevents costly substitutions on site. Q235B handles general framing, bracing, and non-critical secondary steel where formability and weldability matter more than raw strength. Q345B steps into primary load-bearing members — columns, transfer girders, crane beams — where higher yield capacity reduces section sizes and overall tonnage. Our fabrication workshop cuts both grades daily using CNC flame and laser processes, nesting parts from your DWG files to minimize scrap. For projects spanning multiple standards, we supply S235JR, S355JR, SS400, and A572 GR.70 from the same production line, so mixed-grade orders ship in one consignment with separate heat-number documentation for each batch.
Engineering Compliance and Certification Across Export Markets
Structural steel plates destined for EU markets must conform to EN standards and carry CE marking under EN 1090-2, while North American projects typically require ASTM compliance and AISC-compatible fabrication documentation. [NEED_CITE: steel grade equivalence between GB Q-series and EN S-series standards] The plate itself is only half the compliance picture — the cutting process, edge quality, and weld preparation must also meet the specified execution class. Our in-house engineering team reviews shop drawings against the target standard before fabrication begins, flagging tolerance conflicts or material substitution issues early. Third-party inspection through SGS or BV is available for every batch, and our quality documentation package includes dimensional inspection reports, weld maps, and coating certificates where applicable.
Understanding Hot Rolled Plate Grades and Processing Characteristics
The Q-series (Q235B, Q345B) follows the Chinese GB standard system, where the number after “Q” indicates minimum yield strength in MPa. Q345B offers roughly 50% higher yield capacity than Q235B, making it the default choice for primary structural members in industrial buildings and heavy platforms. The S-series (S235JR, S355JR) follows the European EN system and serves equivalent roles — S355JR is the direct counterpart to Q345B in most international projects. ASTM A572 GR.70 targets the North American market with even higher strength for specialized applications.
Hot rolling produces plates with a mill scale surface that provides short-term corrosion resistance during storage and transit. Since our plates ship as-supplied without additional surface treatment, buyers planning painted or coated finishes should factor in blast cleaning at the fabrication stage. The ±1% thickness tolerance across the 1mm–200mm range is standard for hot rolled products and sufficient for most structural applications, though pressure vessel fabrication may require tighter tolerance negotiation at the inquiry stage.
CNC flame cutting handles Q345B and thicker sections efficiently, while laser cutting delivers cleaner edges on thinner Q235B plates and complex geometries. Both processes follow approved WPS procedures, and all cut edges are dimensionally verified before welding begins.
Hidden Costs of Sourcing Plates Without Verified Certification
Ordering hot rolled plates based on price alone — without confirmed heat numbers, verified grade markings, and traceable MTCs — creates risks that surface only during site inspection or structural loading. Material substitution (Q235B delivered where Q345B was specified) passes visual checks but fails ultrasonic testing and load calculations, forcing component replacement and project delays. [NEED_CITE: consequences of material non-conformance in structural steel projects per EN 1090-2] Missing or incomplete documentation triggers customs holds in markets requiring CE marking or ASTM compliance, turning a routine shipment into a demurrage cost. The Q235B Q345B hot rolled steel plate cutting supplier that provides full traceability from slab to cut component protects your project schedule and inspection approval.
Why Engineering Procurement Teams Source From Our Facility
Our operation combines a steel production facility with a dedicated structural steel fabrication workshop — meaning the Q235B and Q345B plates we cut were produced on our own rolling lines, not purchased from third-party traders. This vertical integration gives us direct control over material chemistry, rolling temperature, and surface quality before any cutting begins. Every plate batch carries a heat number that traces back to the original slab test certificate, and our fabrication team uses that same traceability data when preparing weld procedure specifications.
We maintain over 2,800 specifications of raw material in inventory, so standard grades like Q235B, Q345B, S235JR, and S355JR are available for immediate cutting without waiting for mill rolling schedules. Our engineering team provides shop drawing review and material optimization before fabrication, reducing scrap and ensuring cut parts match your assembly sequence. Certified welding procedures (AWS and EN qualified) and qualified welders handle all connection assemblies, and our quality documentation package — including WPS, PQR, weld maps, and dimensional reports — travels with every shipment.
We have delivered fabricated steel components to projects across the EU, Middle East, Southeast Asia, and Africa, and our loading team develops custom packing plans for oversized plates and heavy fabricated assemblies to prevent transit damage.
Documentation & Compliance
- Mill test certificate documenting Q235B/Q345B chemical composition and mechanical properties per GB/T 700 and GB/T 1591, with heat number traceability for every plate batch
- CE certification for structural steel components fabricated to EN 1090-2 execution class requirements
- ISO 9001:2008 quality management system certificate covering the full production and fabrication process
- SGS or BV third-party inspection reports available upon request for material verification and dimensional checks
- Material traceability sheets linking each cut component to its original heat number and slab test certificate
- Complete export documentation including packing list, bill of lading, and certificate of origin for customs clearance
Packaging, Loading & Delivery
- Hot rolled Q235B and Q345B plates bundled with steel strips and edge protectors to prevent corner damage during ocean transit
- Custom-cut plates separated by wooden spacers and wrapped in waterproof paper to preserve the mill scale surface and prevent moisture staining
- Container loading plans optimized for plate width (300–1500mm) and thickness to maximize payload while maintaining weight distribution
- Fabricated components packed on steel cradles with lashing points for oversized assemblies exceeding standard container dimensions
- Heat number and grade markings stenciled on each plate bundle for on-site identification and inspection verification
- FOB, CIF, and DDP shipping terms available with door-to-door logistics coordination for project sites in the Middle East, Southeast Asia, and Africa
Starting Your Plate Cutting Inquiry
Submit your project drawings (PDF or DWG format) along with plate grades, thickness requirements, quantities, and destination port — our team responds within 24 hours with a preliminary assessment covering material availability, cutting feasibility, and production scheduling. For projects requiring EN 1090 or AISC compliance, confirm your target standard and execution class at the inquiry stage so we can align our quality documentation package accordingly.
Get Your Custom Plate Cutting Quote
Share your specifications and engineering drawings to receive a detailed quotation including material, fabrication, coating, and shipping costs — with full mill test certification and third-party inspection support.
Contact: Shandong Xin Jiyuan Special Steel Tube Co., Ltd
Website: www.xjystructure.com
Tel: +86 531 8573 6315
Mobile/WhatsApp/WeChat: +86 188 5315 7756
Email: admin@xjystructure.com
