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The permanent increase of operating parameters of modern multistage centrifugal pumps requires more precise modelling for estimation their dynamic reliability and needs to develop new approach and methodology for the related calculations. It is necessary to change the approach assuming empirical coefficients to another one based on the probabilistic design for analysis of reliability for pumps and their nodes. In this case, the probabilistic parameters of the design features and fluid flow are significant for the calculation (e. g. geometry of gap seals, boundary conditions, material properties) and should be considered. The automatic axial-balancing device of the rotor is one of the most important nodes of multi-stage centrifugal pumps. It operates as the balancing disc for the axial force up to 1 MN. This paper presents the methodology for the numerical calculation of the balancing disc and its influence on the reliability of multistage centrifugal pumps. The proposed approach is based on the criterion of the permissible amplitudes of axial oscillations of the rotor with the automatic axial-balancing device considering probabilistic origin of main geometrical, hydromechanical and operating parameters.

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The use of processing units for the production of mineral fertilizers in the industry in today’s market requires improved product quality and increased productivity. As a result, there is a need to change the design of existing units or some structural elements. Rotary vibroprillers, having a relatively simple design, can be of different designs that directly affect the productivity indicators mentioned above. The study considers the influence of the shape of the basket bottom on the quality of the rotational vibroprillers. After using the governing equation of prills motion in the airflow, a program was developed for automatic control of the rotational speed of the priller based on changes in melt loads. It is established that the size of the spray swath can be changed by varying the rotational speed of the priller. There is a tendency to affect the vibropriller performance by controlling the rotational speed and shape of the basket bottom without performance degradation.