In August, LDV-Systeme took over the development, production and sales activities of VH Lichttechnische Spezialgeräte GmbH based in Iserlohn, Germany. The patented systems have been in operation at leading companies worldwide for more than 25 years. They have proven extremely reliable in steel and non-ferrous metals rolling mills as well as in the automotive and supply industries.
LDV-Systeme has established an international network of partners who provide consulting and other services for an optimal set-up of inspection workstations.
For Heinz Hahne, Managing Director of LDV-Systeme, visual checks are a highly valuable complement to automatic surface inspection systems. “In spite of all progress in the development hardware and algorithms, it will always be up to the human operator to make the ultimate decision about the classification and severity of a defect. Visual inspection remains an indispensible tool for the initial training of automatic systems, for continuous detection rate monitoring and the identification of defects which are invisible to the automatic systems.”
Automatic inspection systems can only operate reliably in the long run, if there is also a work station for a human operator to visually check the strip surface whenever necessary and under optimal lighting conditions. The VH PLS Lichtsegel® (“light sails”) create such conditions as they reflect directional, quasi-parallel light onto the strip surface – making the defect clearly visible. They illuminate the strip surface homogeneously and at an intensity level perfectly adapted to the human eye. This makes visible also small and faint defects and those spreading over a large area, for example, impressions of skin-pass rolls or streaks which cannot be detected by automatic systems.
The “light sails” are particularly suitable for the training and supervision of automatic systems as these also use quasi-parallel light for the illumination of the strip surface. The human eye and the cameras see the surface under similar conditions.
According to Heinz Hahne, the systems represent an optimal added value for the customers: “The visual inspection systems ideally round off our product range. From our experience with optical measurement systems for the steel and aluminium industries we know the conditions under which the systems operate, and we have the knowledge to set up the inspection work stations in an ergonomically optimized way. As our service team is equally familiar with rolling mill environments, we are capable of providing our customers highly competent on-site service.”