When demand outgrows a plant, the reflex is to buy equipment. Often the faster and cheaper answer is to buy guaranteed output from a partner — if the interface is defined properly.
A plant running at 95% utilisation has no capacity problem until the day it has a very large one. New equipment takes months to arrive and longer to qualify; new operators take longer still. Capacity extension — placing a defined slice of your production with a partner — is how plants absorb growth or seasonal peaks without betting capital on a forecast.
The economics are straightforward. A machine you buy for a demand peak sits idle when the peak passes, and its depreciation does not. Purchased capacity scales in both directions: you pay for output in the months you need it. The premium per part over in-house cost is real, but it is usually smaller than the cost of owning idle iron.
What makes capacity extension work is not the machining or the assembly — it is the interface. We ask for the same package an internal line would get: frozen drawings, an approved sample, defined test criteria, agreed packaging. The goal is that parts from the extended line are indistinguishable from your own, down to the label format and the box.
Qualification should be treated as a project with an end date, not an open-ended trial. A typical ramp: first article inspection, a pilot batch with 100% inspection on both sides, then a defined production release. We plan four to eight weeks for this on assembled products. A partner who promises qualified output next week is skipping a step you will pay for later.
Traceability is non-negotiable when two sites feed one customer. Every batch we ship under a capacity agreement carries serial or batch identification that maps to our process records, so a field issue can be isolated to a site, a date and a batch within hours. Without that, one bad lot contaminates the reputation of both lines.
The honest limit: capacity extension suits stable, documented products with real volumes. It does not suit parts whose process knowledge lives in one operator’s hands and nowhere on paper. If that describes your product, the first project is documentation — and that investment pays back even if the parts never leave your building.
— GANI Lifecycle engineering team