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Purpose. To determine complex influence of mode parameters of a vertical vibrating screen and properties of mined rock on efficiency of classification of mineral raw materials. Methodology. On the experimental sample of the screen designed and produced by Department of Machine Mechanics and Mineral Raw Materials Treatment Processes of N.S. Poliakov Institute of Geotechnical Mechanics of NAS of Ukraine, researches on establishment of complex influence of following factors on classification efficiency were carried out: frequencies of rotation of a vibrator shaft, an angle of a direction and amplitude of fluctuations, percentage of throughproduct in the initial product, density and humidity of a material. During experiments one of parameters varied at the fixed values of others, and then experiments repeated at other values of the fixed variables. Findings. Construction of the vertical vibrating screen, which weighs 1.3 tons, is created with the area of a sifting surface 3.2 m2. During experiments we established that the increase in amplitude of fluctuations of the box of the screen, frequency of rotation of the vibrator shaft and the angle of its inclination makes negative impact on classification efficiency. Increase of humidity of mined rock and of throughproduct content in the initial material negatively affects a technological indicator but higher rock density has positive effect. During screening of damp mined rock on the vertical vibrating screen, with high efficiency, values of mode parameters should be as follows: amplitude of fluctuations of the screen box - 1- 2 mm, frequency of fluctuations of 21-25 Hz and the angle of a fluctuations direction in the range of 45-60°. As the spatial fluctuations of the working body are realized the material mixes up, segregates and is sifted faster. Originality. Dependence of complex influence of dominating mode parameters of the screen and rock characteristics on classification efficiency was established. And the law of change of the screening efficiency and quantitative characteristics that allows making mathematical model of process was determined. Practical value. The executed researches allow defining range of the vertical vibrating screen rational parameters for mineral raw materials classification. As the result of research the screen is recommended to wide industrial application [ABSTRACT FROM AUTHOR]