We operate a large number of different hot and cold rolling mills and have additional drawing facilities. This enables us to ensure the high quality of our end products along the entire production chain.
The square billets produced at an earlier stage are heated to a temperature of about 1150°C and then rolled into the desired shape.
In order to obtain a small profile from a billet, the material must be rolled on several successive rolling stands, which is achieved with small profiles by setting a high tensile load ratio.
In this production step, the hot rolled material is used as a semi-finished product for further cold forming.
Hot-rolled semi-profiles are rolled in cold condition. This allows better control of the forming process and higher precision compared to hot rolling.
In cold drawing, the hot-rolled material is used as a semi-finished product for further cold forming.
Hot-rolled preforms are drawn through a rigid tungsten carbide shape to deform the material and achieve the required profile geometry. For profiles with complex shapes and tight tolerances, sometimes up to 8 drawing steps are required to achieve the desired value.
Between each drawing step, the material remains in a heat treatment furnace for hours. By heating to a high temperature and then slowly cooling (annealing), the internal stresses in the steel are released, the microstructure is refined and the hardness is removed after cold forming. Then the material is prepared for the next drawing step.