What it is
Hot-rolled coil (HRC) is the foundational flat-steel product, used directly for structural parts or re-rolled into pipe, cold-rolled coil, and galvanized coil. Because it feeds so many downstream products, grade and thickness accuracy carry through the whole supply chain.
Grades & standards buyers order
| Grade | Standard | Notes |
|---|---|---|
| Q235B | GB/T 700 (China) | General structural grade; the B denotes impact-test temperature class. |
| SS400 | JIS G3101 (Japan) | Widely cross-quoted with Q235 and A36 but not identical — see the comparison. |
| A36 | ASTM A36 (US) | US structural grade requested for US-spec fabrication. |
How it's sold: Sold by metric ton in coils, thickness ~1.2mm–20mm, width up to ~2000mm. Confirm thickness tolerance class and whether width is trimmed or mill-edge.
What drives the price
- Slab/iron-ore cost and mill utilization
- Thickness (thin gauge costs more per ton)
- Width and edge condition (trimmed vs mill edge)
- Grade and impact-test requirements
Lock these into the contract before you pay
Thickness and tolerance class
Rolling to the low end of tolerance ships less steel per ton — a legal grey area unless you specify the class.
Grade equivalence in writing
"SS400 = A36" is an approximation; if your project needs A36, specify A36 and require it on the certificate.
Coil weight and ID
Coil ID and weight let you match physical coils to the mill certificate.
Scams most common to hr coil
Grade Substitution (lower grade shipped than ordered)
A cheaper commercial grade shipped as a structural grade, invisible without chemistry and tensile testing.
Forged Mill Test Certificates (MTC / EN 10204 3.1)
Certificate grade and heat number that do not match the coils loaded.
Head-and-Tail (Sandwich) Coil Loading
Good steel on the visible coil ends with off-spec or damaged material inside.
Red flags in a quote or sample
- Grade cross-quoted between standards without confirming the one you need
- No thickness tolerance class stated
- Price implying rolling to minimum thickness
Already paid and something's wrong?
If you received off-spec hr coil, a certificate that doesn't match, or your supplier has gone quiet after a deposit, move quickly. Recovery odds drop with every day that passes on a wire transfer.
Buying hr coil from China: FAQ
What grades of hr coil can I buy from China?
The most commonly ordered grades are Q235B, SS400, A36. Always pair the grade with its standard on the purchase order so the mill test certificate can be matched to what you actually receive.
What is the most common scam when buying hr coil from China?
Grade Substitution (lower grade shipped than ordered). For this product specifically: A cheaper commercial grade shipped as a structural grade, invisible without chemistry and tensile testing. The defense is to specify the exact grade and standard, require a verifiable mill test certificate, and commission independent pre-shipment inspection.
What should I check before paying for hr coil?
Lock down thickness and tolerance class, grade equivalence in writing, coil weight and id in the contract, verify the supplier is a real manufacturer, and never release the balance until an independent inspection confirms the goods.
I already paid a Chinese supplier for hr coil — what now?
Act fast: contact your bank about a recall on the wire, gather all contracts and communications, report the pattern so others are warned, and review the documented cases to understand your options. The sooner you act on a redirected or disappeared payment, the better the odds.
Related product guides
CR coil
Smooth, tighter-tolerance flat steel for appliances and auto parts. Surface grade and hardness/temper confusion drive disputes.
GI coil
Zinc-coated flat steel for roofing and ducting. Coating-weight fraud is the defining risk because under-coating is invisible.
Steel plate
Thick flat steel for structures, ships, and pressure vessels. Grade/impact-class substitution and thickness shortfall are the key risks.