The mill test certificate (MTC) is your main protection against receiving lower spec than you paid for. Here is what to check line by line, before the vessel sails.
The 6 Lines That Matter
| MTC Field | What to Verify | Red Flag |
|---|---|---|
| Standard + grade | Matches your PO (e.g. DX51D+Z, EN 10346) | Vague entries like “commercial quality” |
| Coating weight test | Actual g/m2 ≥ ordered (e.g. Z275 → ≥275) | Value exactly at minimum on every coil |
| Yield / tensile | Within grade range; G550 → yield ≥550 MPa | Missing mechanical results |
| Thickness | Ordered thickness minus allowed tolerance | TCT quoted where you ordered BMT |
| Coil numbers | Match the packing list one to one | Certificate covers different heat/coil numbers |
| Paint film (PPGI) | Topcoat ≥ agreed microns (e.g. 20-25μ) | No paint thickness line at all |
BMT vs TCT — the Classic Trick
Base Metal Thickness (BMT) excludes coating; Total Coated Thickness (TCT) includes it. A “0.40mm” quote in TCT is roughly 0.35mm BMT — about 5% less steel. Always state BMT or TCT explicitly in your PO and check which one the MTC reports.
FAQ
Can I get a third-party check?
Yes — SGS/BV inspection before loading can verify thickness, coating and packing against the MTC. We support inspections on request.
Should the MTC arrive before payment?
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For L/C orders it is a standard document. For T/T balance-against-copy-docs, insist the MTC is among the copies before releasing the balance.