A material certificate needs a link to the metal you receive
How to connect a mill document to a cut bar, an order line and the finished parts made from it.
Consider a hypothetical delivery of twelve machined spacers, part SP-42, made from stainless steel bar. The certificate lists heat H7318, but the remaining stock is marked H7381. The delivery note says only “stainless steel”. Even if the test results look reasonable, those papers do not yet establish which material became the twelve parts. Resolve the identity gap before treating the certificate as evidence for this delivery.
Start with the order, before reading the test values
A certificate can be genuine and still belong to another delivery. Begin with the purchase-order line: part and drawing revision, material specification and edition, product form, supply condition, quantity and the documentation agreed with the supplier. Then ask which manufacturer document covers the allocated stock. A familiar grade name alone cannot connect these records.
EN 10204 addresses types of inspection documents; it does not replace the ordered material specification. The document type alone does not determine what this purchase requires. Agree the documentation required by the order and applicable requirements before placing the order, rather than adding a certificate request after the stock has been cut. [1]
A heat number is a starting point, not the whole chain
In this example, the heat number identifies the originating melt; a supplier may also use a product, bundle or internal stock number. Ask what each identifier means. H7318 on a certificate and H7381 on a stock label are different references until records explain the difference. An internal stock number may legitimately differ from the mill’s heat number, but the allocation record must connect them; a verbal “same material” is not that connection.
For cut stock, request a record from the original bar identification to the cut pieces and then to the machining batch. A controlled container or job record may be more suitable than stamping a small finished surface. Agree the method before cutting. When a remnant returns to stock or two heats enter one job, preserve their separate allocations so that the next shipment does not inherit an ambiguous label. These are proposed purchasing controls, not a claim that one marking method suits every product.
- 1Marked source bar / retained stock
- 2Manufacturer certificate
- 3PO line and cut / machining allocation record
Illustrative linkage only. Match material identity between stock and certificate, then allocation and quantity between stock, job and order. Lines do not show verified test or processing completion.
Read the documents together: a worked mismatch
The following is an invented receiving review, not a mill certificate template. No acceptance limits or test results have been supplied. Its purpose is to show how a plausible document can fail to identify the goods. The purchase order is PO-240, line 10; machining job J-62 covers twelve SP-42 parts.
Hold the twelve parts with a visible review status and ask for the original receipt, allocation and cutting records. A documented label error may be correctable by the responsible supplier through a controlled correction. Do not edit the manufacturer’s certificate or simply change the stock label to make the numbers agree. If the connection cannot be demonstrated, resolve replacement, additional evaluation or an authorized concession with the responsible buyer and technical authority before release.
| Record / field | What is shown | Decision or missing link |
|---|---|---|
| PO-240 / line 10 | What is shown12 × SP-42; drawing revision C; ordered material specification | Decision or missing linkUse this line as the receiving reference; confirm the exact material and supply condition. |
| Stock photo / identifier | What is shownH7381 | Decision or missing linkDoes not match certificate H7318; hold acceptance until material identity is confirmed. |
| Manufacturer certificate / heat | What is shownH7318 | Decision or missing linkRequest the complete document and confirmation of the stock it covers. |
| Job J-62 / cutting allocation | What is shown12 parts; source-bar allocation absent | Decision or missing linkRequest original stock-to-cut-to-job mapping; quantity alone cannot identify the heat. |
| Finished inspection / process record | What is shownNot yet linked to J-62 | Decision or missing linkCheck agreed dimensions and treatment separately before release. |
The certificate type and the product specification answer different questions
Outokumpu’s ordering guide lists the material standard, grade, product and supply condition separately from the inspection certificate. It describes 3.1 as manufacturer inspection and lists 3.2 separately for inspection by a notified body or a third party. A 3.1 document should therefore not be presented as third-party product certification. Agree the required document type with the supplier when ordering. [2]
For SP-42, compare the actual order with the document’s manufacturer, covered product, grade, dimensions, supply condition, identifiers and relevant reported tests. Ask about omitted pages or unexplained revisions. If the supplier proposes a JIS grade instead of the ordered EN material, require a technical comparison and an approved change. Similar names or a cross-reference table do not automatically establish equivalence, and a certificate title cannot authorize a substitution.
What the source-material certificate does and does not establish
A certificate for the source bar does not by itself establish the finished spacer’s dimensions, surface condition or performance after subsequent processing. In the example, the order also calls for a defined finished dimension and a post-machining treatment. Those need their own agreed inspection and process evidence, linked to J-62 and the delivered parts.
If identity is lost, a new test may help answer a specific material question, but it does not recreate the missing historical connection. Define the required property, sampling, method and decision before testing. A positive result for a selected sample cannot silently become proof of the original heat or every item in a mixed batch. The choice between further evaluation and replacement depends on the use, evidence required and people authorized to accept the risk.
Buy traceability as part of the supply scope
Ask the supplier to price the needed document and identification work with the parts: original-document access, allocation through cutting, separation of mixed lots, processing-record linkage and the delivery format. A low unit price that excludes the work of retrieving records covers a different scope. A clear example record before order placement often reveals that difference more effectively than requesting “full traceability” without explaining what must be traced.
During receiving inspection, accept the traceability evidence only when the relevant delivered quantities and identifiers connect to the required documents and any processing evidence. Record what was reviewed and what remains unresolved. If the order did not establish the necessary controls, improve the next order rather than describing incomplete historical evidence as complete. The inquiry below turns the SP-42 mismatch into a specific request the supplier can answer.
Inquiry to adapt and send
Open supplier questions
For PO-240 line 10, twelve SP-42 parts, drawing revision C, the supplied certificate shows H7318 while the stock photograph shows H7381. Please confirm the meaning of both identifiers and provide the complete manufacturer document, original receiving and cutting allocation records, and their link to machining job J-62 and the delivered quantity. Please also identify the ordered material specification and supply condition covered, and send the separate finished inspection and processing records required by the order. If a labeling error or material substitution occurred, please describe it and propose a controlled correction or replacement. Please do not overwrite the original evidence. We will review the linkage before release.
Sources and scope
- BSI — BS EN 10204:2004, Metallic products. Types of inspection documents
BSI official catalog: document-type scope only. The standard’s paid clauses were not reviewed; no universal legal or 3.1 obligation is asserted.
- Outokumpu — Steel Grades, Properties and Global Standards, May 2013, Table 16, printed p16
Outokumpu technical guide, May 2013, printed p16: distinguishes ordering fields and inspection categories. Historical guidance, not proof of current capability or grade equivalence. The normative standard clauses were not reviewed.