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The main results of the study of hydraulic losses in the suction line and mechanical damages of the impellers of pumps due to cavitation-abrasive wear are given in the article. The scientific task of using theoretical bases for justifying factors affecting the wear rate of pump parts is being solved. On the basis of these theories, a technique is proposed for calculating the wear rate of the elements of the flow-through part of the pumps. During the experimental studies, standard methods of laboratory-bench testing of pumps were used. The operating modes of pumps with minimal wear of their parts are established. Poor hydraulic flow conditions with swirl zones cause an increase in energy losses and a redistribution of flow rates across sections. Wear the parts that are flowing directly proportional to the concentration in the sediment flow, the cube of the flow velocity, the time of action on the pump units. The presence of unsteady vortex regions, especially when the effect of eddy formation increases, leads to fluctuations in the velocities and pulsations of the flow pressure. Cavitation in the pump occurs when the operating modes of the pump differ from the nominal. The increase in volumetric efficiency, the improvement of hydraulic flow conditions to the pump impeller and the reduction of cavitation wear were achieved by the authors in a new pump design that contains guide planes fixed to the throttle plate parallel to the suction nozzle axis with an elastic outer surface. In the same areas of constructive improvement of pump assemblies, it is necessary to search for ways to reduce the negative impact of cavitation and hydroabrasive erosion on the life of pumps.

The data on the hydrodynamic loads on the water body in the presence of cavitating energy without erosive dampers on it are presented. It is shown that these loads increase in comparison with the non-cavitation mode, but, despite this, the use without cavitation dampers in appropriate conditions is advisable, providing favorable downstream regimes and reducing the volume of construction work and the cost of construction. It is proved that for multiple types without erosive energy absorbers, data were obtained on the averaged and pulsating vertical and horizontal loads on the absorbers and the slaughter plate, which allows us to carry out the required calculations of the strength and stability of the elements of the downstream devices. As a result of cavitation and cavitation studies of erosion-free energy absorbers in cavitation stands, coefficients of any resistance C x of several types of aerosol-free absorbers were obtained; as well as pulsation standards measured by “point” sensors for the vertical hydrodynamic effects of the flow on the water culvert in the installation zone of an erosion-free damper.

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The large pumping stations (PS) planned for reconstruction in our republic in terms of consumption, power-to-weight ratio, and controls are the largest in the world: failure of them even for a small period of time can lead to enormous damage. Therefore, the formulation and solution of theoretical problems in the operation of these facilities, taking into account the reliability indicators, is an extremely important national economic task. Until now, the design of the National Assembly, including large ones, has been conducted without taking into account the quantitative index of reliability. The value of reliability has long been underestimated, and error correction required significant costs. Currently, increasing the efficiency of the operation of pumping stations is associated with the development of energy-saving and resource-saving technologies. Diagnostics is one of the modern and perfect ways to determine the main malfunctions that occur in pumping units. The main goal of diagnosing the technical condition of pumping units is to preliminarily identify the occurring malfunctions in it and ensure durability, reliability, reliability, and operational efficiency. The article presents the effect of vibration on pumping units and analysis of methods of vibration diagnostics, information is given on the possibility and advantages of devices for continuous vibration diagnostics.