This paper presents the results of research conducted on a double-frequency screen in a pilot plant that is the screening machine which varies the rotational frequency of the two drive vibrators. This study aimed to determine the constructional foundations of a double-frequency screen on an industrial scale – a machine structurally and dynamically similar which is intended for processing of grained material especially difficult to separate. Sifting this materials is the particularly difficult challenge because of resistances stepping out then finely. Their conquest places before the machine sifting high technical requirements.