When Lufthansa Technik Landing Gear Services UK — a leading commercial-aircraft repair and overhaul business — needed to re-line its chromium plating tank, it contacted Sussex-based NHE (www.nhe.uk.com).

This specialist in the design, manufacture, installation and management of process plant for surface treatment provided a lining solution that was superior to conventional liners for both corrosion resistance and life-span.

Lufthansa Technik’s landing-gear repair and overhaul facility uses Electrolytic Hard Chrome (EHC) plating to improve the wear-resistance of landing-gear components such as axles, inner cylinders, pins, journals and lug bores.

This process requires the use of chromium plating tanks containing hexavelant chromium and chromic acid — a carcinogenic chemical mix that is highly corrosive to concrete and other unprotected substrate materials and is highly regulated under UK law.

The specification of any anti-corrosion system designed for the containment of this chemical must be of the highest standards in order to protect the environment — and Lufthansa employees.

The company overhauls and repairs around 30 landing gears per month; the tank used for their overhaul is 6ft square and 16ft deep, which makes it one of the largest tanks on site.

Historically, Lufthansa Technik used conventional tank liners, which had to be replaced every two years at a cost of about £20,000 each time.

After conducting a comprehensive site inspection, NHE recommended a Koroseal lining and an LFP CrossFilm skirt from Witt Liners, for which it is the sole UK supplier.

The drop-in lining system was formed off-site to match the exact dimensions of the application, taking into account outlets and flanges.

Delivered in one piece, the flexible membrane lining has highly durable seams and corners, which are dielectrically welded through the entire 5mm material thickness, offering far superior chemical resistance compared to anti-corrosion ‘screeds’, which typically rely on much thinner sealing coats.