This article deals with the torque measurement mechanism of the mechanical stirring process. The resulting shear stresses or strains measure the torque. The authors provide a torque meter classification and various methods of torque measurement to accurately measure and control torque. They are important parameters in the design and manufacture of various devices and mechanisms. The paper presents a schematic diagram of a pilot plant to investigate mechanical stirring using the developed torque measurement device without the use of a stroboscope. The method proposed by the authors solves the problem related to simplification of technical torque measurement. The authors calculated the range of liquid level change in the piezometer during the study of the stirring process at the pilot plant, taking into account the minimum and maximum values of pressure in the vessel.