In Hungary, continuous hot-dip galvanized wide strip is produced only by the Galvanizing Works at ISD DUNAFERR Zrt. The base material is non-annealed, so-called full hard cold rolled strip. The width of the initial material is 800 – 1500 mm. The thickness, depending on width, is 0.35 – 1.50 mm. The basic production technology is named after Sendzimir, who worked it out. The production line consists of several coordinated machines, each of which are of individual importance. The coils have a maximum weight of 20 tons and are made endless by means of a welding machine. Afterwards, the strip is drawn through a 50-meter-long heat-treating furnace depending on cross-section size, but with a maximum speed of 60 m/minute, which sets the appropriate mechanical parameters of the finished product mainly by recrystallizing the sheet. Cleaning the sheet surface takes place in the heat-treating furnace in a protective gas atmosphere. The applied temperature values are between 750 and 1200 °C. The sheet cooled down to approx. 450 °C is drawn through a bath containing 120 tons of zinc. A melt with a zinc content of minimum 99 % is applied on the sheet surface in quantities specified in the standards. Once the melt applied on the surface has solidified, the sheet is cooled down below 100 °C. The final mechanical properties and the good flatness of the sheet are provided by a stretcher-bender leveller. After the inhibition of corrosion of the surface with weak chromic acid, coils with the required weights are produced, the mass of which ranges from 3 to 15 tons. Then, galvanized coils are cut, slit or profiled.
