Key concepts & terminology
This app uses four words that sound interchangeable and are not: part, component, file, and part change. Getting them straight is most of the learning curve, because every guide, every tab, and every status depends on the distinction.
The record types
A part is where something sits in this product. A component or file is what that thing is, independent of any product. The same component can fill a part in twenty different bills of materials, which is why it is created once and referenced rather than retyped each time.
Why the part change exists
A bill of materials and a part are both containers. Neither one carries a version. The part change does, and it is what an engineering change approves. That indirection is what lets a bill of materials stay a single stable record while the versions underneath it are drafted, reviewed, released, and superseded.
It follows that a bill of materials is only as released as its part changes. One with nothing approved beneath it has never been through change control, whatever its description says.
Leave canceled and rejected part changes in the bill of materials tree. They are the evidence that a change control process is actually governing the structure, and their comments and history are what demonstrate it. Deleting them removes the proof that anything was ever refused.
The statuses a bill of materials or a part moves through
The statuses a component or file moves through
The lifecycle phases
A product moves through eight phases, each with its own objectives, its own deliverables, and a formal phase review before it is allowed to go further. The point of the structure is that a product is never advanced further than the maturity of its data justifies.
| Phase | What it establishes |
|---|---|
| Identification | The idea, and whether it is worth exploring. Everything here is preliminary and expected to change. |
| Concept | Intended use, user needs, and regulatory classification, still exploratory. |
| Realization | The design itself. Deliverables exist but are not final, and the bill of materials is deliberately incomplete. |
| Pilot | The design built for real, at small scale, with manufacturing and supply data taking shape. |
| Evaluation | Verification and validation evidence, confirming the design does what it was meant to. |
| Commercial | Market release. Everything required is complete, consistent, traceable, and revision controlled. |
| Phase-out | Withdrawal from the market, managed rather than abandoned. |
| Discontinued | The terminal state. The record is formally and permanently closed and the product is no longer supplied. |
Checklist items repeat across phases with only a small change of wording, from "is this available" early on to "is this still up to date" later. That is deliberate. Intended use, standards, classification, architecture, and risk analysis can all change during development, and the gate exists to force each change to be re-confirmed and its downstream impact assessed rather than assumed still valid.
The two roles
Assigning these to people is covered in Set up Product Lifecycle Management.