Continuous hot-dip galvanized wide strip is produced only by Hot-dip Galvanizing and Metalworks of DUNAFERR Rt. in Hungary. The base material is non-heat-treated, 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 machine units that are separately of individual importance. The coils with the maximum weight of 15 tons are made endless by means of a welding machine. Then the strip is drawn through a 50-meter-long heat-treating furnace depending on the cross-section size, but with the speed of maximum 50 m/minute, which sets the suitable mechanical parameters of the finished product mainly by recrystallizing the sheet. Cleaning of the sheet surface takes place in the heat-treating furnace in a protective gas atmosphere. Applied temperature values are: 750-1200oC. The sheet cooled down to almost 450oC is drawn through a bath containing 120 tons of zinc. A melt with the zinc content of minimum 99 percent is applied on the sheet surface in quantities specified in the standards. After the solidification of the melt applied on the surface the sheet is cooled down below 100oC. Final mechanical properties and 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.

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