Strain-Stress State of Steel Strip in Roll Forming Mills

Tube skelps continuously concaved in roll stands of the roll forming mill are usually applied in the process of manufacturing of steel curved curvilinear profiles, which are widely applied in constructional engineering, machine building and other spheres. Special feature of strip bending within roll-pass is three-dimensional model of strains and stresses. The accuracy of engineering evaluation of process conditions of this operation allows the determination of strain-stress state of steel strip when it is deformed in roll stands of the roll forming mill with allowance for thinning and strengthening. Insufficient exploration of the topic causes imprecise determination of energy-power and kinetic process characteristics. In the analysis the position of neutral surface on the fringe of tensile-and-compression deformation zones was amended. The values of ultimate radial stress which exert on the surface and increase with augmentation of friction were evaluated. Special features of strip thinning caused by combined action of torque and tangential stress were analyzed. Force-torque-power conditions at bending with and without allowance for strengthening were introduced. The analysis results amend engineering estimates of developing of roll-formed sections production process.

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