For many buyers, the mill test certificate (MTC) is the most important document in the shipment. It is their proof that the material matches the order. A missing value or a typo can hold goods at the port or trigger a rejection.

The certificate types

Most buyers refer to EN 10204, which defines several inspection document types:

  • Type 2.2 — a test report from the manufacturer based on non-specific inspection.
  • Type 3.1 — specific inspection results, validated by the manufacturer's authorised inspection representative, independent of production.
  • Type 3.2 — like 3.1, but also validated by the buyer's representative or a third-party inspector.

For critical applications such as oil & gas, pressure equipment or structural work, buyers usually ask for 3.1 or 3.2.

What buyers check first

Traceability

Buyers look for a clear link between the certificate and the material they receive: heat number, batch or lot number, purchase order, product description and quantity. The heat number on the certificate should match the marking on the material.

Chemical composition

Each element is compared with the limits of the ordered grade and standard. Common checks include carbon, manganese, silicon, phosphorus and sulphur for carbon steels, plus chromium, nickel and molybdenum for stainless and alloy grades. For non-ferrous metals, buyers check purity and alloying elements.

Mechanical properties

Tensile strength, yield strength and elongation are compared with the standard. Impact test values and test temperature matter for low-temperature applications. Hardness may be required for some products.

Standards and grade

The certificate must name the exact standard and grade ordered — for example EN 10025-2 S355J2+N or ASTM A240 316L — not just a general description.

Errors that cause delays

  • Values copied from an old certificate that do not match the current heat.
  • Results that fall outside the standard's limits without anyone noticing.
  • Missing signatures or the wrong certificate type.
  • Unclear scans that cannot be read or verified.

Making certificates trustworthy

The best suppliers check every value against the standard before the certificate leaves the plant, keep a searchable archive by heat number and PO, and send every certificate in the same clean, professional format.

That is exactly what we built MTCMitra for: certificates generated from your test data, with grade limits built in, every value checked automatically against the standard, and a professional PDF in your own format.