Аннотация:The article outlines the methodology and results of solving the task of measuring the temperature field and the thermoelastic stress in the horizontal rolls in the process of rolling of a broad-flanged beam in the universal beam mill stand. The authorsets and solves the problem of measuring the temperature field of the composite rolls. The author discloses the algorithm of measuring the thermoelastic stress in the horizontal rolls with the known temperature field. The article contains distribution diagrams of the tangential thermoelastic stress in the cross section of a horizontal roll in the process of rolling beams in the universal mill stand. The author shows the effect of the heat emission factor on the level of the tangential stress in cooling the rolls with water. The theoretical research determines the value of the tensile tangential stress which lowers the endurance of the horizontal rolls of the universal mill stand. The article determines the resultant stress field in the horizontal composite rolls caused by the rolling pressure and the cyclic thermal effect with the residual stress taken into account. The author provides recommendations how to increase the endurance of the composite rolls of the universal beam mill.