FIELD: equipment for investigation of grinding and mixing processes in feed mill industry. ^ SUBSTANCE: laboratory installation has rotor, set of replaceable working tools, working chamber casing positioned for free rotation relative to axis of rotor and defined by torque measuring devices. Working chamber casing is composed of transparent closure, shell, faceplate, and transparent mounting plate positioned above transparent closure outside casing. Position of mounting plate may be adjusted in vertical plane. Laboratory installation is further provided with diametrically opposite branch pipes made in the form of devices for determining air flow rate through inlet collector. Retaining bearing is positioned in axially aligned relation with respect to rotor shaft, the latter being inserted into said bearing. Replaceable working tools are mounted in tiers on rotor shaft. Charging openings are formed in transparent closure of working chamber. Gaps between charging openings in transparent closure and branch pipes a
