IMPROVEMENT OF THE METHOD FOR CALCULATING DEFORMATION PARAMETERS IN THE ROLL PASS DESIGN FOR THE WIRE MILL

Currently, analytical methods, including system analysis and computer simulating, are widely used in the development and construction of rational roll pass design. However, the known methods and solutions are not exhaustive, which solve the problem completely. The methodology for calculating the parameters of rolling deformation during the calibration of rolls for rolling wire rod in system of the gauges "round-oval-round" on graded modern continuous mills has been developed, taking into account the balance of the forces in the deformation zone and the longitudinal stability of the process. It provides coordination of geometric, kinematic and force parameters in the deformation zones of the rolling mill itself and the wire block. 
The calculation is carried out against the direction of rolling, in terms by the corresponding strip, taking into account temperature conditions and rolling in the field of minus tolerances the dimensions of the metal. Longitudinal rolling stability in every stand is determined based on the calculation the average resulting internal forces of plastically deformable metal. Numerically solving the boundary value problem for the Karman equation with known rolling parameters and changing the entering angle, the corresponding angle of the neutral section is found, the value of which is equal to the found kinematic one. 
The results of the test calculations are quite close to the real data of rolling the round bar and a wire rod with a diameter of 8 mm on a mill 400/200 of PJSC "KAMET-STEEL". At the same time, the broadening of the metal is determined analytically in accordance with the physical conditions of the balance forces and constancy of the seconds’ volumes of the metal in the zones of deformation. The shape of the ovals obtained by the provided method is more convex. The system influence of metal friction conditions in the rolls on the longitudinal stability of rolling and the stability of the process was established.