Every tonne of steel CSACI ships travels with a Mill Test Certificate (MTC) — and for most buyers it is the single most important document in the package. Yet “do you provide MTCs?” is often asked without specifying which type, and the differences matter contractually.
The EN 10204 document types
EN 10204 defines four levels of inspection document:
| Type | Name | Who validates | What it tells you |
|---|---|---|---|
| 2.1 | Declaration of compliance | Manufacturer | ”We declare it conforms” — no test results |
| 2.2 | Test report | Manufacturer | Results from non-specific testing (not your batch) |
| 3.1 | Inspection certificate | Manufacturer’s independent QA department | Results from your actual heat/batch, validated by a department independent of production |
| 3.2 | Inspection certificate | Manufacturer plus an independent third party (SGS, BV, Lloyd’s…) | 3.1 content, counter-validated externally |
Type 3.1 is the industry standard for pipe, plate and structural steel — it ties test results to the specific heat numbers stamped on your material. Type 3.2 adds a third-party witness and is typically reserved for critical service or when the purchase order demands it.
How to read a 3.1 certificate
When a shipment arrives, check four things before anything is released to the yard:
- Heat number match — the heat numbers on the certificate must match the hard stamps or stencils on the pipe or plate. No match, no acceptance.
- Chemistry section — element-by-element mass percentages against the standard’s limits. For API 5L PSL 2, also verify the carbon-equivalent values (CE IIW / CE Pcm) are within limits.
- Mechanical section — yield, tensile and elongation against the grade minimums; for impact-tested material, the Charpy values (average and individual minimums, with test temperature).
- Standard and supplementary requirements — the certificate must cite the exact specification revision and any annexes (e.g., API 5L Annex J for offshore) your order invoked.
Common pitfalls we see in trading
- 2.2 documents offered where 3.1 was needed — a price that looks too good sometimes hides this downgrade. Check the document type box first.
- Re-certification gaps — when material changes hands between stockists, the chain back to the original mill certificate must remain unbroken.
- Country-of-melt requirements — US and some EU buyers must document melt-and-pour origin; this comes from the MTC, so confirm it appears before shipment, not after.
Our documentation standard
CSACI ships every order with an EN 10204 3.1 Mill Test Certificate, Certificate of Origin and packing list as standard, and arranges 3.2 third-party certification (SGS, BV or equivalent) when your order requires it. Documentation questions are part of the quoting conversation — send us your requirement and we’ll confirm the certification package alongside the price.