Techsil Ltd have found great success with their UV repair system for repairing pin holes in laser welds and brazes on doors, bonnets and trunk joints in both aluminium and steel. The system combines Vitralit® 4282 Mod II UV-curing adhesive and the Bluepoint LED light curing equipment. Cell Integrators have installed seven Techsil repair stations at three UK car manufacturing plants last year, with another one to be added in the UK soon. Techsil have now sold their first system to a Chinese assembly plant too.
The process only takes a few seconds. The robot on the inspection line carries out an in-process inspection and if it identifies a pin hole, it rejects the panel out of the line. The operator either repairs it locally or takes the panel to a re-work station. The whole repair takes less than 30 seconds, with the adhesive cured in place by a dual system of UV light to fix it and then an anaerobic cure as the adhesive is starved of oxygen.
The repair creates a seal and eliminates a leak path before the panel goes to the paint shop. This system eliminates porosity in the visual surface of the brazed seam & repairs cracks that could propagate further across the panel. The maximum quantity of pin holes repaired in one panel is four and the scope of pinhole that can be filled is from 0.3mm to 3mm diameter. Deep holes can be filled in sandwich fashion by building up two layers of adhesive. Typically the car manufacturer has spent less than 50p on a repair which saves them scrapping a panel costing in excess of £100.
More information on Vitralit® 4282 Mod II
More information on the Bluepoint LED light curing equipment
