Wire Rod Mill

The wire rod block has a group and not individual drive for all stands, the shaping in the different passes is done with a calculated tension between the stands in the block in other words the shaping is not tension free like in the intermediate mill. The tension between the stands depends first from constant parameters like the shape of the groove, working roll diameter in the groove, roll diameter relations between the stands, calculated cross section reduction but also from variable parameters like bar temperature, spread of material in the groove depending from type of material and temperature of the material. The different types of material can have different deformation resistance and consequently different roll forces. With higher roll forces the groove open according the mill modulus. All that means that geometrical tolerances like diameter and roundness of the finished rod is not better than the tolerances of the intermediate mill train rolled entry section into the block due to the non uniform tension in the bar created by difference spread in the groove caused by different cross sections of the entering bar, due to different bar temperature, material properties regarding spreading and elongation.