In the practice of pumping oil wells, thermo-boric conditions occurring inside the well are important. The neglect(or omission) of heat exchange processes occurring in the well may lead to a decrease in the performance of pumping equipment, reduced turnaround time and accidental failures of downhole equipment. In this paper, on the basis of the obtained theoretical and experimental conclusions made by well-known experts in the field of hydromechanics and thermodynamics, the issues of heat exchange processes occurring inside an operating well are considered. The heat transfer for a mixture of water-feldspar particles with a turbulent mode of motion in the annular space is investigated. The combined effect of the particle size on the heat transfer coefficient, the hydraulic diameter of the annular space, the ratio of the hydraulic diameter to the average particle diameter, the concentration of particles in the mixture, the Prandtl and Reynolds numbers is experimentally shown. It has been established that omission of the influence of a mechanical impurity in determining the heat exchange coefficient may lead to its understating more than 2 times, and the temperature of the electric motorby 10 °C. The selection of the technological parameters of the operation of the ESP in such a way that the value of dp falls within the interval from 2 to 6 will help improve heat exchange and protect the electro motor from overheating.

Many oil companies have serious difficulties with complicating factors as the appearance of mechanical impurities in the production of wells, the deposition of asphalt-resin-paraffin substances (ARPSs) on the equipment walls, salt deposition, and corrosion of metals. The presence of mechanical impurities ranks first in emergency stops of pumping equipment. Mechanical impurities cause wear on equipments and pump jammings. In most cases, solid scaled particles (SSPs) cause metal corrosion and ARPS precipitation. Filtering devices are described. They are designed for a specific concentration of SSPs, which do not always protect pumps at higher concentrations. Therefore, work is underway to explore the possibilities of gravel filters. Learning is important. This article discusses the use of equations known in filtering theory to determine the parameters for the movement of liquids through a gravel filter used in the oil industry to clean up mined products. Conducted analytical studies and calculations to determine the speed of movement of flows through the packing of gravel filters. The selection of new boundary conditions, slightly different from the exact, simplifies the solution of the resulting differential equations, and an increase in the calculated parameters by 5-10% (Howe method) eliminates the probability of error. Thus, the obtained values of the filtering parameters allow correctly choose the size and geometry of the filter elements.