R. F. Iskhakov, CJSC Research and Production Enterprise "MASHPROM"; S. P. Burkin, Ur. Federal University named after the first President of Russia B. N. Yeltsin; A. V. Bryantsev, CJSC Research and Production Enterprise "MASHPROM", Russia; iskhakov@mashprom.ru

Rolling in multi-roll passes is prospective owing to possibility of processing of low-ductile metals and alloys, rise of rigidity of rolling stands and precision of rolled stock, provision of high extension capacity. The paper considers the rolling method in passes of cone rolls for manufacture of simple sections using the following technological routes: round-square, square-round, square-square. The schemes of forming round and square roll passes are displayed. Cone rolls provide possibility of elastic-plastic twisting of billets and forming of rolled spiral texture. The torque arising during billet twisting creates additional tangential stresses in reduction area; they cause lowering of contact pressure and rolling force. Specific residual twisting angles are shown for different technological routes. The mechanism of round billet twisting in four-roll square pass of cone rolls is shown. It was established that transversal (applying to rolling axis) component of contact friction forces has influence on the value of twisting angle of section (in addition to shape of deformation area). Solution of the problem of drive construction for the stands with multi-roll passes is proposed. Simplified technique of calculation of specific and general twisting angles of rolled billet is suggested and obtained results are compared with experimental data.

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