Obsolescence management: how UK manufacturers keep plants running without ripping out the machine

Obsolescence management is now a routine maintenance task, not a once-a-decade crisis. When a valve range or manifold base reaches end-of-life, the usual fallout follows: extended lead times, unplanned downtime, and costly re-engineering. However, with the right plan you can keep legacy assets productive, standardise for the future, and reduce risk across your plant.

At PSI Technologies, we replace discontinued pneumatic valves and manifolds with form-fit-function (FFF) equivalents, ISO 5599-1 / ISO 15407-1 drop-ins, and pre-built manifolds — quickly and with minimal disruption.

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Obsolescence is no longer a surprise event — it’s a maintenance line item. When a valve family or manifold base goes end-of-life (EoL), the risk is the same every time: blown lead times, unplanned downtime and unbudgeted re-engineering. The good news? With a structured approach you can keep legacy assets productive, standardise for the future, and de-risk your spares position.

At PSI Technologies, we help plants replace discontinued pneumatic valves and manifolds with form-fit-function (FFF) equivalents, ISO 5599-1 / ISO 15407-1 drop-ins, and pre-built manifolds — fast.

Why PSI — and why MAC — for obsolescence management

Direct access to MAC Valves. As MAC’s sole UK distributor, we provide factory-accurate cross-references, dependable spares, and quick technical answers.
Standards-led engineering. Our obsolescence management approach aligns with recognised best practice rather than ad-hoc swaps.
Speed to fit. Photo-based identification, FFF replacements where possible, and pre-built, pressure-tested manifolds to cut downtime.

What “obsolescence” actually means

In engineering terms, the discipline sits under obsolescence management — a formal practice with its own international standard, IEC 62402:2019, covering policies, processes and lifecycle planning from design through end-of-support. IEC

You’ll also hear DMSMS (Diminishing Manufacturing Sources & Material Shortages): the loss — or impending loss — of a manufacturer, supplier or raw material. It’s a proactive risk area, not just a procurement headache.

Procurement steps that strengthen obsolescence management

Standardise platforms. Move legacy islands to ISO 5599-1 / ISO 15407-1. As a result, you widen sourcing options and simplify approvals.
Dual-source by design. Specify functions and performance, not brands. An ISO base makes this credible.
Document the spec. Capture function (5/2 or 5/3), Cv, ΔP, duty cycle, ambient limits, IP/Ex rating, and any accessories such as silencers or regulators.
Monitor lifecycles. Track vendor notices, ask for roadmaps, and plan LTB windows early. In turn, you avoid last-minute surprises.

Typical obsolescence scenarios on the shop floor

Discontinued inline valve: your go-to 3-way/4-way unit is EoL. The quickest fix is an FFF replacement that matches porting, function and envelope so pipework, PLC I/O and documentation stay put.
Legacy manifold no longer supported: migrate the station to a current ISO 5599-1 (sizes 1/2/3) or ISO 15407-1 (01/02) platform for long-term interchangeability; add spare stations and dual-pressure zoning while you’re there. ISO
ATEX coil unavailable: swap to a current Ex-rated option with the correct Ex marking and T-class (e.g., Ex db/Ex tb or intrinsic safety with a certified barrier).
OEM kit no longer sold: rebuild the sub-assembly with current catalogue parts and documentation.

Our playbook for fast, low-risk replacements

Capture the facts
Send us a photo of the valve label and base, coil voltage/connector, a shot of the manifold, and any zone classification if it’s in a hazardous area.
Cross-reference
We map to a MAC Valves equivalent or an ISO drop-in, keeping function (5/2, 5/3 etc.), flow (Cv), response and pressure rating aligned. If the original footprint is proprietary, we’ll design adapter plates or swap the base to ISO.
Validate
Checks include flow/ΔP, duty cycle, media, IP rating, and if applicable Ex marking and T-class. (Hazardous-area gear must align with ATEX/UKEX documentation on site.)
Build
We assemble and pressure-test manifolds (side/bottom porting, dual-pressure zones, sandwich regulators/flow control plates) and label I/O for a straightforward install. (See common ISO sandwich/plate options defined by major vendors as a guide.)
Stock strategy
Agree buffer stock for critical lines and plan any last-time-buy (LTB) actions for at-risk parts — both are recognised practices in IEC 62402 and DMSMS guidance.

The standards shortcut: design for interchangeability

When you move to an ISO interface, you’re buying choice. ISO 5599-1 and ISO 15407-1 define the mounting/porting footprint (and in the case of ISO 5599-2, plug-in electrics), so future replacements are faster to source and qualify. It’s the single biggest lever to reduce lifecycle risk on manifolds. ISO

Procurement: de-risk the next outage

Standardise platforms: move legacy islands to ISO 5599-1 / ISO 15407-1 to widen sourcing options. ISO
Dual-source by design: specify functions and performance, not brands; an ISO base makes that credible.
Document the spec: record function (5/2/5/3), Cv, ΔP, duty cycle, ambient limits, IP/Ex rating and any accessories (silencers, regulators, flow controls).
Monitor lifecycles: track vendor notices, push suppliers for roadmap visibility, and plan LTB windows where appropriate — straight out of IEC 62402 good practice.

Quick wins we deliver every week

EoL inline → FFF MAC swap keeping brackets, pipework and wiring intact.
Obsolete manifold → ISO rebuild with spare stations and labelled I/O.
Non-ATEX install → Ex upgrade with correct Ex db/tb or Ex i approach and documentation.
Unreliable stick-slip tooling → MAC balanced-design 4-way valves for repeatable response across pressure fluctuations (typical MAC advantage).

Need an answer today? Email a photo of your valve label and base — we’ll cross-reference and quote the nearest drop-in.

FAQs

What’s the difference between an FFF replacement and an ISO “drop-in”?
FFF matches the original footprint/porting and behaviour; ISO drop-in moves you to a standardised base (ISO 5599-1 / ISO 15407-1) so future spares are easier to source. ISO

Can I keep my panel wiring the same?
Usually, yes. We match coil voltage/connector and manual overrides. If the original used a proprietary plug-in, we’ll propose the cleanest wiring update.

Do I need to re-certify ATEX equipment if I change the valve?
Stay within the same Ex protection concept, category, temperature class and ambient and keep the documentation trail tidy; your site COMPEX/DSEAR procedures will guide the level of review. (We’ll ensure the replacement’s Ex marking matches the zone.)

Is CE vs UKCA an issue for replacements?
For most industrial categories managed by DBT — including equipment for potentially explosive atmospheres — CE-marked products continue to be recognised in Great Britain indefinitely, giving flexibility during transitions. GOV.UK