Experimental Research And Theory Of Slab Head Bending In Rolling Processing

Slab head bending is a common deficiency of shape in rolling plate. Because height and lengthwise direction of workpiece elongate non-homogeneously in deformation zone, which produces slab head bending (head curling up or head curling down) and increase geometric defective plates of crops in rolling, so lots of cobbles and defective plates are produced. Slab head bending leads to destroy machine or cause accident, and production is stopped, increasing time of servicing machine, that directly influence in increase of efficiency of production and economy.Mathematic models on condition of ratio of up-down roll diameter, entrance angle, ratio of roll rotation speed and friction coefficient in slab head bending are defined to use mechanical equilibrium condition equation, kinematics equation and boundary condition. Variant head bending equations indicate degree of slab head bending to audio-visually reflect merit and defect of them. Finally, experiments results are proved to precision of computation results, Mathematic models are good. Chief conclusions follow:(1)In condition of ignoring other factors, equation of slab head bending about ratio of frition indicate that ratio of friction in interval of [0.105, -0.105], with increase of ratio of frition, value of slab head bending increases.(2)In condition of ignoring other factors, equation of slab head bending about ratio of roll diameter indicate that ratio of roll diameter in interval of [0.846, 0.97], with increase of ratio of roll diameter, value of slab head bending increases.(3)In condition of ignoring other factors, equation of slab head bending about ratio of roll rotation speed indicate that ratio of roll rotation speed in interval of [1.224, 2.303], with increase of ratio of roll rotation speed, value of slab head bending increases.(4) In condition of ignoring other factors, equation of slab head bending about entrance engle indicate tha entrance engle in interval of[0, 0.105], with increase of entrance engle, value of slab head bending increases.