Description
Vertically integrated steel plate supply — Own steel mill produces SS400, Q235, Q345, and SPHC hot rolled carbon steel plate with full heat-number traceability from slab to cut component.
Technical Specifications
| Parameter | Value |
|---|---|
| Designation | SS400 / Q235 / Q345 / SPHC Hot Rolled Carbon Steel Plate |
| Product Type | Steel Plate |
| Steel Grade | SS400, Q235, Q345, SPHC |
| Standard | AISI, API, CE, JIS, ISO 9001, GB5310, GB3087, GB6479, GB9948, GB/T8163, GB8162, GB/T17396 |
| Section Shape | Plate / Sheet |
| Size Range | Thickness: 0.2–400 mm; Width: 600–2500 mm; Length: 600–12000 mm |
| Technique | Hot Rolled |
| Surface Treatment | Black painting / Varnish paint / Anti-rust oil / Hot galvanized / Cold galvanized / 3PE |
| Tolerance | ±5% |
| Ends | As per requirement |
| Application | Construction / Structural steel fabrication / Industrial platforms / Pressure vessels / Shipbuilding / Building frames |
| MOQ | 5 Tons |
| Origin | Shandong, China |
Application Suitability
| Industry | Typical Applications |
|---|---|
| Structural Steel Fabrication | Column base plates, beam splice plates, gusset plates, truss connection nodes |
| EPC & General Contracting | Warehouse frames, logistics center structures, industrial plant supports |
| Infrastructure | Bridge gussets, foundation anchor plates, retaining wall brackets |
| Pressure Vessel & Industrial | Tank shell plates, platform grating supports, vessel head blanks |
| Shipbuilding | Deck plates, bulkhead stiffeners, hull structural panels |
What Internal Lamination Defects Cost When Mill Certificates Are Missing
A plate that looks flat on the outside can fail ultrasonic testing after cutting — and by then the shipment has already cleared customs.
Overseas buyers sourcing SS400 Q235 Q345 hot rolled carbon steel plate supplier materials from third-party traders often receive Mill Test Certificates that cannot be traced back to a specific heat number. When internal lamination or slag inclusion defects exist, they remain invisible until the plate is cut and ultrasonic inspection is performed on site. The result: entire containers rejected, weeks of project schedule lost, and no accountable party to claim against.
Material traceability is not optional for EN 1090 or AISC-compliant projects — it is the foundation of structural liability. [NEED_CITE: EN 1090 structural steel fabrication execution class requirements]
Matching Plate Thickness and Grade to Structural Load Paths
Hot rolled carbon steel plate in SS400, Q235, Q345, and SPHC grades covers the full spectrum of non-alloy structural requirements across JIS, GB, and equivalent international standards. Thickness from 0.2 mm to 400 mm allows a single SS400 Q235 Q345 hot rolled carbon steel plate supplier to serve both thin gauge cladding support plates and heavy base plates for column-to-foundation connections. The key is matching the grade to the design code: Q345 provides higher yield strength for primary load-bearing members, while SS400 and Q235 suffice for secondary framing and non-structural attachments.
Engineering Compliance and Surface Treatment Selection
Structural steel fabrication for EPC projects requires plates that meet dimensional tolerance, weldability, and surface preparation standards before they ever reach the workshop floor. Hot rolled plates in Q345 grade are routinely specified for moment-resisting frames where higher strength reduces section weight, while SPHC suits forming operations requiring superior ductility. Surface treatment selection — anti-rust oil for short-term inland transit, hot-dip galvanizing for coastal or industrial corrosion environments, 3PE coating for buried or submerged conditions — must align with the project’s environmental exposure class. [NEED_CITE: ISO 12944 corrosion category and coating system selection]
Understanding Grade Equivalence Across Standards
SS400 (JIS G 3101), Q235 (GB/T 700), and S235JR (EN 10025-2) occupy similar yield strength ranges but differ in chemical composition limits, impact testing requirements, and delivery conditions. Q345 (GB/T 1591) corresponds broadly to S355JR/J0/J2 in the EN system, offering higher strength for heavy structural applications. SPHC (JIS G 3131) is a hot-rolled commercial quality grade optimized for cold forming rather than structural load-bearing. Selecting the correct SS400 Q235 Q345 hot rolled carbon steel plate supplier material requires confirming not just the grade designation but the specific testing and certification requirements of the governing design code.
Hidden Costs of Unverified Plate Procurement
Purchasing hot rolled carbon steel plate from traders without in-house production creates three categories of hidden cost: material substitution risk (lower-grade plate shipped under higher-grade designation), certification gaps (MTC not matching actual heat chemistry), and dimensional non-compliance (thickness tolerance exceeding ±5% affecting connection fit-up). On EN 1090 EXC2 or EXC3 projects, these defects trigger factory production control audits, third-party re-inspection charges, and potential rejection of fabricated assemblies. [NEED_CITE: EN 1090 factory production control and material traceability obligations]
Why Vertically Integrated Supply Reduces Project Risk
XJY Structure operates its own steel production facility with three production lines and over 2,800 raw material specifications, eliminating the gap between mill and fabricator. Every plate carries a heat number traceable from slab to finished cut component. The in-house fabrication workshop performs CNC plasma and flame cutting, drilling, bending, and welding per approved WPS procedures — all under one quality management system certified to ISO 9001 and compliant with EN 1090 and AWS standards. This integration means shop drawings, material procurement, fabrication, and quality documentation flow through a single point of accountability.
Documentation & Compliance
- Mill Test Certificate documenting Q345 chemical composition and mechanical properties per GB/T 1591, with heat number traceability from in-house steel production
- CE certificate confirming EN 1090 execution class compliance for structural steel components fabricated from SS400 and Q235 plates
- ISO 9001 quality management certificate covering the full fabrication process from cutting through welding and surface treatment
- SGS or BV third-party inspection report available for dimensional verification, NDT testing, and coating thickness measurement
- Material traceability report linking each cut plate to its original heat number, slab position, and rolling schedule
- Complete customs documentation package including packing list, bill of lading, and certificate of origin for destination-country clearance
Packaging, Loading & Delivery
- Hot rolled SS400 and Q235 plates bundled with steel strips and edge protectors to prevent coating damage during ocean transit
- Anti-rust oil or varnish paint applied to plate surfaces before packing, with PE sheet wrapping for hot galvanized or cold galvanized finishes
- Container loading optimized for plates up to 12000 mm length, with wooden dunnage separating tiers to distribute weight and prevent shifting
- Custom cutting to project-specified dimensions available before shipment, reducing on-site waste and secondary processing
- Heat number and grade identification stenciled on each plate end, matching the Mill Test Certificate for site verification
- FOB, CIF, and DDP shipping terms supported with professional oversized cargo handling and complete export documentation
How to Initiate a Fabrication-Grade Plate Inquiry
Submit your project drawings (PDF or DWG), required steel grades, thickness and dimensional specifications, applicable standards (EN 1090, AWS, AISC), and destination port. XJY Structure responds within 24 hours with a preliminary assessment, detailed quotation including material, fabrication, coating, and logistics costs, and a shop drawing timeline. Third-party inspection and complete quality documentation packages are confirmed at the quotation stage.
Frequently Asked Questions
Q: What is the difference between SS400, Q235, and Q345 for structural applications?
A: SS400 and Q235 are non-alloy structural grades with similar yield strength ranges, suitable for secondary framing and general construction. Q345 offers higher yield strength for primary load-bearing members and moment-resisting frames. The selection depends on your project’s design code and structural calculations.
Q: Can you provide Mill Test Certificates with full heat number traceability?
A: Yes. As a vertically integrated SS400 Q235 Q345 hot rolled carbon steel plate supplier with in-house steel production, every plate carries a heat number traceable from slab to finished component. The MTC documents chemical composition and mechanical properties per the applicable standard.
Q: Do you offer custom cutting and drilling services before shipment?
A: Yes. Our in-house fabrication workshop performs CNC plasma and flame cutting, drilling, and bending to your exact project dimensions. This reduces on-site processing and ensures dimensional accuracy verified against approved shop drawings.
Q: What surface treatment options are available for different environments?
A: We offer black painting, varnish paint, anti-rust oil, hot-dip galvanizing, cold galvanizing, and 3PE coating. Selection depends on the project’s corrosion environment: anti-rust oil for short-term protection, hot-dip galvanizing for coastal or industrial exposure, and 3PE for buried or submerged conditions.
Q: Are your products compliant with EN 1090 for European projects?
A: Yes. Our structural steel fabrication is certified to EN 1090, and we provide CE marking, complete quality documentation, and material traceability required for EU market entry.
Get Your SS400 Q235 Q345 Hot Rolled Carbon Steel Plate Quote with Full Traceability
Send your project specifications, steel grades, and destination port to receive a detailed quotation and Mill Test Certificate sample within 24 hours.
Company: 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
Address: No.11889, Jingshi West Road, Lulian Group, Jinan City, Shandong Province, China
