The work provided is a continuation the development of research work on the process of pumping high-viscosity liquids and is aimed at creating a universal technique of recalculating the performance curves of dynamic small-sized pumps from water to high-viscosity liquid. The practical need to develop such a technique became relevant after obtaining different results when using existing methods of predicting performance curves for hydrodynamic oil well pumps. The expediency of carrying out studies aimed at clarifying the scope of the technique for calculating the work parameters of a well oil centrifugal pump, which is being developed, is substantiated, and more thorough analysis of the structure of conversion coefficients taking into account the scale factor and flow regime in the hydraulic flow parts of the studied pumps.

The work is devoted to determining the influence of methods and recommendations for the design of a volute casing on the flow structure and the efficiency of the double-entry centrifugal pump. Volute casing designed by the constant-velocity method of the fluid according to the recommendations of A. Stepanoff, volute casing designed by the method of conservation of angular momentum of the flow, and the recommendations of C. Pfleiderer and A. Lomakin were designed and researched. The proposed designs were compared with the base volute casing. The analysis was performed based on the results of numerical simulation of the working process of the pump in the software ANSYS CFX at different flow rates. One impeller geometry and a constant volute casing outlet diameter were used to minimize the influence of other pump design factors on the working process of the volute casing. The distribution of pressure and velocity in the volute casing is analysed. Analysis of velocities and angular momentum along the volute casing showed the same deviation of them values. In general, the characteristics of the flow inside the volute casing conform indicated method. The article provides recommendations for choosing a method of designing a pump volute casing.

The research results that presented in the article are focused on decreasing the intensity of pressure pulsations in the flowing part of centrifugal pumps. The aim of the work is researching influence of changes in construction and/or operating pump parameters on pressure pulsations amplitude. Basing on the research results, were determined the main sources of pressure pulsations in the flowing part of the spiral centrifugal pumps and the reasons of increasing their amplitude during pump operation mode at supply 0.3Qopt…0.7Qopt. The article presents information about dependencies of pump head and pressure pulsations amplitude on construction and operating pump parameters, such as: number of blades (z), blade width at the impeller outlet (b2), ratio of volute initial diameter to impeller outer diameter (D3/D2), angle of output edge inclination (φ), rotor rotation frequency (n) and blades position of impeller halves in relative to each other (shift step - ψ).

The article considers one of the ways to increase the ability of a dynamic pump to pump gas-liquid mixtures - the application of the vortex principle of energy transfer. This scheme is embodied in a torque flow pump, which is able to pump mixtures with a gas content of up to 0,40 - 0,45 without additional devices for preparing the mixture. Experimental researches the influence the value of the volumetric gas content on the performance characteristics of the torque flow pump of the "Turo" type are given. The analysis of influence of structure of a stream of gas-liquid mixture on the value of the critical gas content in the interblade channels of the impeller is represented and developed a physical model of decrease the parameters of the torque flow pump.