Description
Factory-Direct Q345 Plate Processing — Hot rolled carbon steel plates from 0.2 to 18 mm thickness, laser cut and welded in-house with ±0.02 mm tolerance control.
Technical Specifications
| Parameter | Value |
|---|---|
| Designation | Q345 Carbon Steel Plate |
| Product Type | Steel Plate |
| Steel Grade | Q195, Q215, Q235, Q345, SS490, SM400, SM490, SPHC, SPHD, SPHE, SPHF, SAE1002, SAE1006, SAE1008, SAE1010, S25C, S35C, S45C, 65Mn, SPHT1, SPHT2, SPHT3, SPHT4, QstE |
| Standard | ASTM, BS, DIN, GB/T, JIS |
| Thickness | 0.2–18 mm |
| Width | 610 / 760 / 840 / 900 / 914 / 1000 / 1200 / 1250 mm |
| Tolerance | Thickness ±0.02 mm, Width ±2 mm |
| Technique | Hot Rolled |
| Surface Treatment | Coated / Galvanized / Iron gray / Brown / Partial ochre / Temperature oxidation pattern |
| Processing Service | Bending, Welding, Decoiling, Cutting, Punching, Laser Cutting |
| Special Use | High-Strength Steel Plate, Manganese Wear-resistant |
| Application | Shipbuilding, Automobile, Bridges, Buildings, Machinery, Pressure vessels, Fabrication, Laser cutting & welding processing |
| MOQ | 1 Ton |
| Origin | Shandong, China |
Application Suitability
| Industry | Typical Applications |
|---|---|
| Machinery Manufacturing | Equipment base plates, wear liners, conveyor frames, hydraulic press components |
| Steel Structure & Construction | Bridge gusset plates, building connection plates, column base plates, crane beam web plates |
| Shipbuilding & Pressure Vessels | Hull structural panels, bulkhead stiffeners, welded vessel shells, nozzle reinforcement plates |
| Automotive & Transport | Chassis reinforcement plates, trailer floor supports, suspension bracket blanks |
| General Fabrication | Laser-cut brackets, welded assemblies, punched flanges, bent enclosures |
Why Thickness Tolerance Decides Laser Cutting Yield on Q345 Orders
A ±0.02 mm thickness tolerance on hot rolled Q345 plate means your CNC laser program runs true from the first cut to the last — no focus drift, no slag rework, no scrapped blanks.
When procurement teams order carbon steel plate for precision fabrication, the most expensive mistake rarely comes from the steel grade itself. It comes from thickness variation that forces laser operators to constantly refocus the cutting head, or from width inconsistency that wastes nesting space. On a Q345 carbon steel plate cutting processing supplier order running 18 mm plate for structural brackets, even minor deviation means the kerf width shifts, edge quality degrades, and weld prep bevels come out uneven. Buyers who have received plates with loose tolerance know the cost: slowed throughput, higher gas consumption, and rejected parts at final inspection [NEED_CITE: laser cutting tolerance requirements for structural steel plate].
Matching Q345 and 45# Plate to Structural and Wear Applications
Hot rolled Q345 plate delivers the yield strength range that structural engineers specify for bridge gussets and building connection nodes, while S45C and 65Mn grades serve machining-intensive applications where surface hardness and wear resistance matter — think conveyor liners and crusher jaw plates. The 0.2 to 18 mm thickness range covers everything from light gauge enclosure panels to heavy structural splice plates, and the Q345 carbon steel plate cutting processing supplier capability includes laser cutting, bending, punching, and welding prep in a single production flow. This eliminates the need to ship raw plate to a separate processor, reducing handling damage and lead time.
Engineering Compliance and Certification Requirements
Structural applications demand traceability from heat number to finished part. Q345 plate supplied under GB/T must carry mill test certificates showing chemical composition and mechanical properties per heat, while export orders to EU markets require CE marking under EN 10219 or EN 10210 frameworks depending on the forming method [NEED_CITE: CE marking requirements for structural steel plates in EU construction]. Pressure vessel and shipbuilding applications add another layer — material must conform to ASTM or JIS equivalents with third-party inspection by SGS or BV before shipment. The Q345 carbon steel plate cutting processing supplier maintains an in-house physical and chemical laboratory for re-testing dimensional accuracy, tensile properties, and chemical composition, ensuring every plate leaving the facility meets the standard specified on the purchase order.
Steel Grade Selection and Hot Rolling Process Fundamentals
The Q-series grades (Q195 through Q345) follow the Chinese GB/T system where the number indicates minimum yield strength in MPa — Q345 replaces the older 16Mn designation and offers higher strength for structural welding applications. The S-series (S25C, S35C, S45C) follows JIS G 4051 for carbon steel machinery structural quality, where the number represents approximate carbon content in hundredths of a percent — S45C at roughly 0.45% carbon responds well to quenching and tempering for wear parts. Hot rolling produces a mill scale surface that appears iron gray on low carbon grades and brown on higher carbon or alloy compositions; this scale provides temporary corrosion resistance during storage but must be removed before welding or painting. The partial ochre surface on weather-resistant variants indicates controlled oxidation for outdoor exposure applications. Thickness tolerance of ±0.02 mm on hot rolled Q345 carbon steel plate cutting processing supplier output reflects precision control of rolling mill gap settings and temperature monitoring during the finishing passes.
Hidden Costs of Incorrect Grade Specification and Missing Documentation
Ordering Q235 when the drawing calls for Q345 means the fabricated structure may pass visual inspection but fail load testing — the yield strength gap between these grades is significant enough that deflection under design load exceeds allowable limits. Similarly, accepting plates without proper mill test certificates creates customs clearance risk on EU and North American shipments, where border authorities require EN 10204 3.1 or 3.2 documentation for structural steel [NEED_CITE: EN 10204 inspection document types for steel products]. Surface defects like laminations or edge cracks discovered after laser cutting waste not just the plate but the machining time already invested. A Q345 carbon steel plate cutting processing supplier with verified certification and in-house testing eliminates these risks at the sourcing stage.
Procurement Confidence Through Vertical Integration and Certification
Our production facility operates dedicated hot rolling lines for carbon steel plate in thicknesses from 0.2 to 18 mm across multiple width options, with laser cutting, bending, and welding processing completed before shipment. The in-house physical and chemical laboratory tests every heat for composition and mechanical properties, generating mill test certificates that accompany each order. Full international certification includes ISO 9001:2015 quality management, Lloyd’s CE marking for EN compliance, Singapore FPC certification, and SGS/BV third-party verification available on request. Custom non-standard dimensions and cut-to-size blanks are available with 1 Ton MOQ, and professional container loading with anti-damage measures ensures plates arrive without edge deformation or surface scratching.
Documentation & Compliance
- Mill test certificate documenting Q345 chemical composition (C, Si, Mn, P, S) and mechanical properties (yield strength, tensile strength, elongation) per GB/T 1591, with heat number traceability
- CE certificate confirming conformity with EN 10219 cold formed structural hollow sections or EN 10210 hot finished profiles as applicable to plate processing method
- ISO 9001:2015 quality management system certificate covering hot rolling, laser cutting, and welding processing operations
- SGS or BV third-party inspection report verifying dimensional tolerance (±0.02 mm thickness), surface quality, and marking accuracy before container loading
- Material traceability sheet linking each plate to heat number, rolling schedule, and test results for pressure vessel and shipbuilding applications
- Complete customs documentation including packing list, bill of lading, and certificate of origin formatted for destination country requirements
Packaging, Loading & Delivery
- Hot rolled Q345 plates bundled with steel strips and edge protectors to prevent corner damage during ocean transit, with anti-rust oil applied to bare plate surfaces
- Galvanized plate orders packed with plastic wrapping over steel strip bundles to preserve zinc coating integrity and prevent white rust formation
- Container loading optimized for 610 to 1250 mm width plates, with wooden separators between layers to distribute weight and prevent surface scratching during transit
- Laser cut blanks and punched plates nested and strapped separately by part number, with heat number and steel grade marked on each piece for site traceability
- Custom length cutting available per drawing specification, with kerf compensation calculated for Q345 and S45C grades to ensure final dimensions meet tolerance
- Shipping terms FOB, CIF, or DDP with professional container loading supervision and tracking until arrival at destination port or project site
Getting Your Q345 Plate Processing Quote Started
Submit your drawing or specification sheet including steel grade (Q345, S45C, 65Mn, or other), thickness, width, quantity, and processing requirements (laser cutting, bending, welding prep, or raw plate). Our team responds within 12 hours with unit pricing, lead time, and mill test certificate confirmation. For non-standard dimensions or wear-resistant manganese plate applications, request custom cutting samples and third-party inspection arrangement before production begins.
Frequently Asked Questions
Q: What is the difference between Q345 and S355JR for structural applications?
A: Q345 follows the Chinese GB/T 1591 standard while S355JR follows EN 10025-2; both offer similar yield strength ranges for structural welding applications. Our Q345 carbon steel plate cutting processing supplier can provide mill test certificates showing chemical composition and mechanical properties per the standard specified on your purchase order, and third-party inspection confirms compliance before shipment.
Q: Can you laser cut Q345 plate to custom shapes with tight tolerance?
A: Yes, laser cutting service covers Q345, S45C, 65Mn, and other grades in thicknesses from 0.2 to 18 mm, with dimensional tolerance controlled by the ±0.02 mm plate thickness specification. We provide cutting samples for approval before full production runs, and mill test certificates accompany each order for traceability.
Q: What surface treatment options are available for hot rolled Q345 plate?
A: Hot rolled Q345 plate comes with mill scale (iron gray on low carbon, brown on higher carbon grades), or can be supplied galvanized for corrosion protection, or with partial ochre treatment for weather-resistant outdoor applications. The surface condition is selected based on your end use — structural welding typically requires descaled plate, while outdoor storage applications benefit from the ochre finish.
Q: Do you provide CE certification for Q345 plate exported to EU markets?
A: Yes, our facility holds Lloyd’s CE certification and can provide EN 10204 3.1 or 3.2 mill test certificates required for EU customs clearance and construction project approval. Third-party inspection by SGS or BV is available on request to verify dimensional tolerance, surface quality, and marking before container loading.
Q: What is the minimum order quantity for custom cut-to-size Q345 plate?
A: The MOQ is 1 Ton for both standard size hot rolled plate and custom laser cut blanks. Non-standard dimensions outside the 610 to 1250 mm width range can be produced with typical lead times of 25 to 45 days depending on specification complexity.
Start Your Q345 Carbon Steel Plate Order Today
Send your specification sheet with steel grade, dimensions, quantity, and processing requirements to receive pricing and mill test certificate confirmation within 12 hours.
Contact SD XJY Pipe
Website: www.sdxjypipe.com
Tel: +86 531 8573 6315
Mobile/WhatsApp/WeChat: +86 188 5315 7756
Email: admin@sdxjypipe.com
Address: No.11889, Jingshi West Road, Lulian Group, Jinan City, Shandong Province, China
