Material and special process certificate traceability checklist

The chain starts at the dock. Check the mill certificate against the purchase order before the bar, plate or sheet enters stock, because a mismatch found after cutting turns into scrap.

Compare specification, temper, form and heat number. A 7075 plate arriving with a 6061 certificate is rare, but a wrong temper on the right alloy is far easier to miss at the receiving desk. Tag every piece at once. Mill certificates often cover a whole heat shared across several customers, so the quantity will not equal yours, which is normal if heat number and specification match.

Rejects go to quarantine. Receiving staff need a short reference of what to compare and the authority to refuse a delivery, otherwise the check is a signature on whatever arrived.

Cutting splits one heat into many parts. Record which blank went to which job, keep the heat tag with the remainder, and mark the heat number on each blank itself where the drawing allows it. Paper tags fall off bar ends. Bare aluminium keeps no memory.

Serial numbers come next. For each serial, store the heat number and the job it was cut on, and let offcuts returned to stock keep their tag and remaining quantity. Write it all down at the saw. Memory fails months later, and an auditor will not accept a guess about which plate a bracket came from, however confident the machinist sounds.

Spreadsheets begin to creak here. Two people editing the stock sheet at once can overwrite a split, and nobody notices until an auditor asks for the cut list.

Outsourced steps each produce a certificate: a heat treat furnace record, an anodise or plating batch certificate, passivation or an NDT report with the technician’s level and method. Each should name your part number, your quantity and the specification used, so a stray certificate cannot be attached to the wrong lot. Chase late certificates every week. Late paperwork is normal.

Record the processor too. Many customers keep an approved process source list, and a certificate from a processor missing from that list becomes an audit finding whatever the quality of the work.

Check the quantity returned equals the quantity sent and note rejected pieces by serial, then copy the furnace load or anodise tank batch reference into your own record. Processors quote that reference first.

Before shipping, one view should show the serial, the heat lot, each process certificate and the inspection report, so a gap shows at a glance.

The certificate of conformance is a statement signed in your name, so build it from linked records at shipment and never from last order’s template. It cites those records.

Archive the pack by purchase order and serial, so a search by serial, heat number or purchase order finds it in one step, not an afternoon. If your filing needs a person who remembers where things went, the system depends on that one memory rather than on records.

Pick a shipped serial. Rebuild its history from records alone. Time it, and list every missing item.

Repeat the drill with a part that went through two outside processors, because the second round usually exposes the weakest link in the chain.

Fix the weakest link first, whether it is receiving, splitting or filing, and review the chain whenever a customer audit report arrives at the quality office. Every auditor question joins your list.