When the part is discontinued: reading the notice before the deadline
The notice went out months before production stopped, so the letter nobody read is not paperwork — it is a deadline that has already been running. Whether you meet it decides between a planning task and an emergency.

The letter nobody read
Obsolescence is not wear, and that changes who carries it
IEC 62402:2019 defines obsolescence as the transition of an item from available to no longer available from its manufacturer, while it is still required. Every part of that sentence does work: the item is not broken, it is not superseded in your works — it has left the supply side, and the consequence lands entirely on the operator.
Which makes it a planning discipline rather than a purchasing accident. The maker usually announces it, with a typical lead time of six to twelve months and, in most cases, a named successor. The notice goes to the distribution channel and to registered customers.
If it never reached the person holding the spanner, that is a routing problem — and the cheapest one on this page to fix.
- Search the vocabulary alongside the part number, not the part number alone
- A part number search returns shops; the vocabulary returns the maker’s own announcement
- That announcement is the document that says what to buy instead
Five letters, five deadlines
The vocabulary of discontinuation
These abbreviations are not interchangeable, and the difference between them is measured in months of remaining supply.
| Term | In full | What it means | What it asks of you |
|---|---|---|---|
| NRND | Not recommended for new designs | Still in production and still orderable, but no longer to be designed in | Nothing urgent — but stop specifying it into new machines now |
| EOL | End of life | Production will end on a stated date | Establish your remaining demand and the last order date |
| LTB | Last time buy | The final ordering window before production stops | Size the quantity for the remaining service life, not for this year |
| PCN | Product change notice | A change to the product, its process, its material or its source | Check whether the change affects your qualification, not just the form |
| PDN | Product discontinuation notice | The formal announcement of discontinuation, usually with a successor | Read the successor section first — it often resolves the whole case |
| FFF | Form, fit, function | A replacement that matches physically, mechanically and functionally | Document the equivalence; nobody will remember the reasoning in five years |

The window that attracts trouble
Scarce and valuable at the same time — which is when the grey market arrives
The methods are well documented, particularly for electronic components: sanding down and re-marking the top surface, substituting used parts in original packaging, reselling production rejects, relabelling a lower specification as a higher one. A frequent entry path is electronic waste recycling.
Vigilance at goods-in does not protect you — a re-marked component looks correct by design. The channel protects you: authorised stock, a traceable purchase history, and a willingness to pay more than the cheapest broker price for a part whose failure stops a line.
A second protection costs nothing. Buy the replacement while the original is still available and run them side by side.
- A component at three times the list price is still cheaper than one unplanned shift of downtime
- A qualification completed in normal operation beats one improvised at a stopped machine
- Record who released the equivalence, and when — in five years nobody remembers
The order of operations
Six moves once a part is discontinued
In this order. Skipping the first step is the most common way to buy a replacement you did not need.
Confirm that it really is discontinued
"Not in stock" and "not available" are different statements. Ask the manufacturer directly, or find the notice. Distributors sometimes drop a product from their range long before its maker stops making it.
Read the named successor first
Most discontinuation notices name one, and it is frequently a drop-in. Where it is not, the notice usually says what changed — connection, footprint, material, tolerance — which is exactly the list your qualification has to cover.
Establish your remaining demand honestly
Not annual usage, but total usage over the remaining service life of the machines that use the part, plus a failure allowance. Machines planned for replacement in three years need a very different quantity from those with fifteen years ahead of them.
Size the last-time buy against storage risk
Stock is not free of decay. Elastomers age even unstressed and have a limited storage life; electrolytic capacitors dry out; sensitive electronics need their packaging intact. Guidance on storing rubber products exists in ISO 2230. A ten-year buy of a five-year part is money written off.
Where no successor exists, qualify a form-fit-function replacement
Compare it against the requirement, not against the old part’s data sheet — the two are not the same document. Where the part sits in a safety function or inside an approved assembly, the replacement needs a fresh assessment rather than a comparison table.
Update the parts list before you close the case
The old number left in the list is how the same search gets repeated in two years. Record the successor, the date, the reason and who approved the equivalence, next to the position it replaces.
Where to look next
From the notice back to a part number
- Identifying the right partType plates, part numbers and the search order that works.
- Ask about a specific partType designation, year of construction and serial number decide the list.
- Seals and gasketsWear parts with a known mechanism — the obvious shelf candidates.
- Sight glassesOrdered by dimension and material rather than by an old number.
Two ways in
Buy the wear part today — or bring the discontinued range with you
What we make ourselves stays available on our own account, and it is priced and specified at the position. If your business is remaining stock and last-time buys, this is where the people searching for them already are, and a listing costs neither a fee nor a monthly charge.