Reading a Mill Test Certificate Before It Costs You
A mill test certificate (MTC) is the DNA record of your steel: which heat it came from, its measured chemistry and its mechanical test results. Most certificate problems are visible on the document itself, before the steel ships, if you know where to look.
The Three Checks That Catch Most Problems
- Heat number matching: every bundle tag on the shipment must trace to a heat number on the certificate. Unmatched tags mean unverified steel.
- Chemistry within the ordered grade window: check C, Mn, S, P (carbon steels) or Cr, Ni, Mo (stainless) against the standard's limits, not just against the word 304 or S355.
- Mechanical results vs standard minimums: yield, tensile and impact values should exceed the standard minimum with margin. Values exactly at minimum across every test deserve a question.
Certificate Types: 2.1, 2.2 and 3.1
Under the EN 10204 framework, a 2.1 certificate is a declaration of conformity without specific test results. A 2.2 adds non-specific test data. A 3.1 is issued by the manufacturer's authorised inspection representative independent of the production department, and it is what most European projects require. Always specify the certificate type you need at order time; upgrading after production is not always possible.
Every Angesen shipment travels with its mill test certificates, and heat numbers can be verified directly with the issuing mill. If you want a second set of eyes, we arrange third-party inspection (SGS, BV, TUV) before loading. Contact us to discuss your inspection requirements.