A passivation service with reliable turnaround

Passivation is a chemical process designed to improve corrosion resistance on stainless steel parts. Its purpose is to remove iron filings and other contaminants left behind as a result of machining and fabrication processes.

William Hughes promises that customers will get their parts as and when they're needed. The William Hughes factory at Stalbridge, Dorset contains an 80m2 clean room and state-of-the-art automated passivation plant.

The hi-tec passivation process, which is Nadcap accredited and Honeywell Aerospace approved, involves a series of precise chemical treatments that eliminate contaminants from stainless steel surfaces. Its novel functionality means that there is no 'dunking' of component baskets from station-to-station, as with traditional systems. Instead, the plant performs "fluid transfer", moving chemical solutions from holding tanks into the main processing unit as required. This prevents damage to the parts as they are not required to move.

The entire process is fully automated and PLC controlled with typical treatments featuring nitric acid and rinse cycles, followed by a further rinse in deionised water. The parts are air-dried in a clean room environment to prevent recontamination.

This systematic approach ensures that the stainless steel is not only corrosion-resistant but also maintains its mechanical properties and surface finish, crucial for high-stakes manufacturing applications.

Other plant functionality includes an ultrasonic passivation facility and a rotary option where parts can be rotated through the solution, thus filling air gaps in more complex and tubular-type components for example.

Whether you require passivation for medical instruments, precision-engineered components or complex assemblies, William Hughes provides results that meet stringent industry specifications supported by rigorous quality control and, most importantly, on schedule delivery.