Description
Factory-Direct Cold-Rolled Plates — Every SS400 Q235B SA516 Gr70 cold-rolled high-carbon steel plate ships with in-house lab-tested chemistry and original mill test certificates, cutting out trading markups.
Technical Specifications
| Parameter | Value |
|---|---|
| Designation | SS400 / Q235B / SA516 Gr70 Cold-rolled High-carbon Steel Plate |
| Product Type | Steel Plate |
| Steel Grade | SS400, Q235B, SA516 Gr70, C20 |
| Standard | JIS G3101, GB/T 700, ASTM A516 |
| Section Shape | Flat plate |
| Size Range | Thickness 1.0–2.0 mm |
| Technique | Cold-rolled |
| Surface Treatment | Non-oiled |
| Hardness | Full Hard |
| Application | Pressure vessels, industrial fabrication, structural components, machinery parts |
| Origin | Shandong, China |
Application Suitability
| Industry | Typical Applications |
|---|---|
| Pressure vessel manufacturing | Boiler end caps, heat exchanger shells, storage tank walls using SA516 Gr70 |
| Machinery fabrication | Gear blanks, base plates, conveyor frame gussets in SS400 and Q235B |
| EPC infrastructure projects | Embedded plates, anchor brackets, equipment skid decking |
| Industrial structural assembly | Bracing gussets, stiffener plates, connection nodes |
Why Negative Tolerance on Thin Plates Costs More Than You Think
A 0.5 mm deviation on a 1.5 mm cold-rolled plate means a 25% weight shortfall — and a rejected shipment.
When procurement teams order SS400 Q235B SA516 Gr70 cold-rolled high-carbon steel plate in the 1.0–2.0 mm range, thickness tolerance is where margins disappear. Cold-rolled plates at this gauge are especially vulnerable to negative tolerance stacking: if a mill ships −0.8 mm on a 1.2 mm spec, the plate fails both weight-based billing and structural load calculations downstream [NEED_CITE: cold-rolled steel thickness tolerance standards per ASTM A568]. I have seen entire containers held at destination ports because the caliper readings did not match the mill test certificate. The fix is simple — verify every plate with a micrometer before loading, and require chemistry-matched MTCs tied to heat numbers.
Matching Full-Hard Cold-Rolled Plates to Precision Fabrication
Full-hard cold-rolled plates in the 1.0–2.0 mm thickness range deliver the flatness and dimensional consistency that laser-cutting and CNC punching demand. The non-oiled surface means no degreasing step before welding or powder coating — a detail that matters when you are feeding SS400 Q235B SA516 Gr70 cold-rolled high-carbon steel plate into automated press lines. For pressure vessel fabricators working to ASTM A516, SA516 Gr70 provides the carbon content and tensile profile needed for moderate-temperature service, while SS400 and Q235B cover general structural and machinery applications at lower cost.
Engineering Compliance and Certification Requirements
Pressure vessel plates must conform to ASTM A516 for North American ASME code work, and the mill test certificate must document chemical composition and tensile results per heat number [NEED_CITE: ASTM A516 specification requirements for pressure vessel plates]. For EU-bound shipments, CE marking under EN 10210 or equivalent structural standards determines whether customs clears the cargo or holds it for re-inspection. Cold-rolled full-hard plates also require clear documentation of the rolling reduction ratio and annealing status, since full-hard condition affects formability and bend-radius calculations on the shop floor.
Decoding the Steel Grades and Cold-Rolling Process
SS400 (JIS G3101), Q235B (GB/T 700), and SA516 Gr70 (ASTM A516) represent three distinct standard systems — Japanese, Chinese, and American — each with different carbon ceilings and manganese ranges. SA516 Gr70 targets pressure-containing applications with tighter chemistry control, while SS400 and Q235B serve as general-purpose structural grades. Cold-rolling pushes the plate through reduction at room temperature, increasing hardness and improving surface finish compared to hot-rolled equivalents. The full-hard condition means no subsequent annealing — the plate arrives at maximum hardness from the rolling mill, suitable for applications where flatness and wear resistance outweigh deep-draw formability. The non-oiled surface eliminates hydrocarbon residue, which matters for downstream coating adhesion and weld quality [NEED_CITE: cold-rolled steel surface condition effects on coating adhesion].
Hidden Costs of Sourcing the Wrong Grade or Missing Documentation
Ordering Q235B when the drawing calls for SA516 Gr70 means the plate will not pass ASME code inspection — no amount of re-testing will fix a chemistry mismatch. Similarly, shipping without original mill test certificates or with certificates that do not match heat numbers stamped on the plate leads to customs holds and third-party re-inspection fees that often exceed the plate cost itself [NEED_CITE: steel import documentation requirements for customs clearance]. For thin-gauge cold-rolled plates, negative tolerance abuse also means you receive less material by weight than you paid for — a loss that only shows up during incoming inspection.
Why Source SS400 Q235B SA516 Gr70 Cold-Rolled High-Carbon Steel Plate from Xin Jiyuan
Our in-house physical and chemical laboratory tests every heat before release — chemistry, tensile, and hardness results go directly onto the mill test certificate, not a third-party lab report days later. We hold ISO 9001:2015, Lloyd’s Register EU CE, Singapore FPC, and verification from SGS and BV, so your compliance paperwork is complete at origin. With over 2,800 specifications across our production lines, we can supply non-standard widths or custom-cut lengths for your specific nesting layout. Our professional loading team optimizes container weight distribution for heavy plate cargo, and we handle FOB, CIF, and DDP terms to 50+ countries with real-time shipment tracking.
Documentation & Compliance
- Mill test certificate per EN 10204 3.1 documenting SA516 Gr70 chemical composition (C, Mn, Si, P, S) and tensile properties by heat number
- CE certificate covering EN 10210/EN 10219 compliance for EU market customs clearance
- ISO 9001:2015 quality management system certificate covering the full cold-rolling and inspection process
- SGS or BV third-party inspection report available for independent verification of SS400 and Q235B plates before shipment
- Material traceability linking each plate to its heat number, rolling batch, and laboratory test record
- Full customs document package including packing list, bill of lading, and certificate of origin for SA516 Gr70 pressure vessel plates
Packaging, Loading & Delivery
- Non-oiled full-hard plates bundled with steel strips and edge protectors to prevent surface scratching during ocean transit
- Thickness-specific separation using timber dunnage between layers to avoid cold-weld or moisture trapping on 1.0–2.0 mm gauge plates
- Container loading plans optimized for SA516 Gr70 and SS400 plate weight distribution, maximizing payload within 20ft and 40ft limits
- Heat number and steel grade stenciled on each plate edge for traceability during incoming inspection at destination
- FOB Qingdao, CIF, and DDP delivery options with professional port coordination for heavy plate cargo to EU, North America, and Southeast Asia
Start Your Procurement with Verified Chemistry and Clear Specs
Submit your drawing specs, steel grade requirement (SS400, Q235B, or SA516 Gr70), quantity, and destination port — we respond within 12 hours with pricing, lead time, and a sample mill test certificate for your review.
Request Your Cold-Rolled Plate Quote with Mill Test Certificate
Send specifications to admin@sdxjysteel.com or reach us via WhatsApp at +86 188 5315 7756.
Frequently Asked Questions
Q: What is the difference between SS400, Q235B, and SA516 Gr70 for cold-rolled plate applications?
A: SS400 (JIS G3101) and Q235B (GB/T 700) are general-purpose structural grades with similar carbon and manganese ranges, suitable for machinery frames and structural components. SA516 Gr70 (ASTM A516) is a pressure vessel grade with tighter chemistry control and specified tensile requirements for moderate-temperature service. The choice depends on your engineering code and application.
Q: Can you provide mill test certificates for SA516 Gr70 plates shipped to North America?
A: Yes. Every heat of SA516 Gr70 is tested in our in-house laboratory, and the original mill test certificate documents full chemical composition and mechanical properties per ASTM A516. We also arrange SGS or BV third-party inspection if your project requires independent verification.
Q: Do you offer custom thickness or non-standard widths for cold-rolled plates?
A: We can supply non-standard widths and custom-cut lengths beyond the standard 1.0–2.0 mm range, subject to MOQ requirements. Share your nesting layout or cutting list, and we will confirm availability and lead time.
Q: What surface condition do the plates ship in, and does it affect weldability?
A: Our cold-rolled plates ship in non-oiled, full-hard condition. The non-oiled surface means no degreasing is required before welding or coating, which improves coating adhesion and weld quality. Full-hard condition provides maximum flatness but limits deep-draw formability.
Q: How do you ensure thickness tolerance on 1.0–2.0 mm cold-rolled plates?
A: Every plate undergoes micrometer measurement at our in-house lab before shipment. Thickness results are documented against the mill test certificate, and we reject any plate outside the specified tolerance band before it reaches the loading area.
