Traceability when stockholders cut material from master lengths or plates

Buying from stock often means the piece delivered to the project is not the same physical size that originally left the mill.

A 12 m beam may be cut into shorter lengths. A large plate may be divided into several small plates. A tube may be cut into fixed pieces.

The technical challenge is straightforward:

Can every delivered piece still be linked unambiguously to the original material and its mill inspection certificate?

If the answer is uncertain, the certificate alone is not enough.

What traceability is trying to preserve

A traceability system links:

delivered piece → stockholder cutting record → original master item → heat/test unit → original MTC

The exact identifiers vary by product and mill, but may include:

• heat number;
• cast number;
• plate number;
• mother plate number;
• coil number;
• batch or lot;
• product number;
• unique stockholder piece ID.

The system does not need to look identical at every company. It needs to preserve an auditable link.

What EN 10204 means for intermediaries

EN 10204 distinguishes the manufacturer's inspection document from what an intermediary does with it.

An intermediary such as a stockholder or distributor can transmit the manufacturer's original inspection document or a copy, but the manufacturer's document should not be altered into a new "mill certificate".

The key procurement principle is that the documentation must be accompanied by suitable product identification so the material can be traced back to the certificate.

For partial deliveries, the quantity shown on a copy can be adapted to the actual partial quantity where the required traceability procedure is maintained.

See EN 10204 certificate types 2.1, 2.2, 3.1 and 3.2.

A practical cutting workflow

A good stockholder procedure normally looks like this:

1. Receive and identify the master material.
   Verify its physical marking against the MTC.

2. Assign an internal stock identity.
   The stock record should retain the original heat/plate/coil information.

3. Issue a cutting instruction.
   The instruction identifies which master item will be cut and into which customer pieces.

4. Transfer identification.
   Before the original marking is lost, each resulting piece receives the required traceability marking/tag.

5. Record the cut.
   The stock system or cut map links the new piece IDs back to the mother item.

6. Deliver the original MTC/copy plus stockholder documentation.
   The buyer can follow the chain back to the original manufacturer's certificate.

Marking can be physical or controlled by another system

Depending on the product and project, traceability may be maintained using:

• hard stamping;
• paint marking;
• low-stress stamping;
• tags;
• barcodes/QR codes;
• piece labels;
• cut plans;
• ERP stock IDs.

The permitted marking method depends on the product and project. For some critical components, uncontrolled hard stamping may be prohibited.

The important point is not the technology—it is whether the identification survives handling and can be audited.

What happens when a plate is split

Plate stock deserves special attention because one original plate can become many customer pieces.

A robust record should be able to show:

• original plate number/heat;
• original dimensions;
• cut layout;
• dimensions of each resulting piece;
• new piece IDs;
• remaining offcut identity;
• quantity delivered to each customer.

If further testing is carried out on a cut piece, the test report should identify exactly which piece/sample was tested. Additional testing should not be allowed to blur the distinction between the original mill certificate and a later laboratory report.

What happens when beams or tubes are cut

The same principle applies to long products.

If the original heat number is stamped only at one end, cutting may remove that marking from most pieces. Identification therefore needs to be transferred before or during cutting.

A buyer asking for 20 pieces cut from five master lengths should be able to determine which finished pieces came from which master length/heat where the order requires that level of traceability.

Stockholder documents are not new mill certificates

A stockholder may issue:

• delivery note;
• cutting certificate;
• declaration linking pieces to the original MTC;
• traceability statement;
• re-stamping statement;
• test report for additional tests.

Those documents can be important, but they do not make the stockholder the original material manufacturer.

When the project requires a manufacturer-issued EN 10204 inspection certificate, the original manufacturer remains central to that certification chain.

What if the original identification was lost?

This is a serious issue.

Chemical PMI can sometimes help identify an alloy family, and mechanical/NDT retesting can establish selected properties, but neither automatically recreates the original manufacturing history.

If traceability to the original certificate has genuinely been lost, the buyer should not assume it can be restored merely by testing.

The possible disposition—re-identification, downgrade, additional testing, rejection—depends on the product standard, project specification and purchaser/engineering approval.

Buyer checklist for cut stock

Before accepting cut material, check:

• original manufacturer and MTC;
• original heat/plate/coil identifier;
• physical identification on every delivered piece where required;
• stockholder's traceability statement or cut record;
• dimensions and quantity;
• whether marking was transferred;
• whether the original certificate remains available;
• whether any test reports are original mill tests or later supplementary tests;
• whether the project requires witnessing of re-marking/cutting;
• whether the stockholder's procedure has been approved or audited.

For the general piece-level process, see Maintaining traceability after cutting steel.

Procurement takeaway

When buying cut stock, do not ask only:

"Do you have the MTC?"

Ask:

"How will you prove that this exact delivered piece belongs to that MTC after cutting?"

That is the practical difference between possessing a certificate and maintaining traceability.

References and verification sources

• DIN EN 10204:2005-01 — Metallic products, types of inspection documents
• DIN EN 10168:2004-09 — Steel products, inspection-document information
• Dillinger — Customer information concerning inspection documents according to EN 10204