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When determining the stress state of an elastic hollow ball when filtering liquid through its wall, it is necessary to solve the stress problem for the case of liquid filtration to the center of the ball with a decrease in pressure in its cavity. This case represents for us an element of the general problem of the stressed state of the annular filter behind the casing during well operation. First, the problem of liquid filtration is solved -pressure changes in the body under study are determined during liquid filtration. Then the equilibrium equation with respect to radial deformation is solved. A change in the sign of the filtration potential leads to a change in the tangential stresses on the well wall to a value equal to a tripled depression of reservoir pressure (with radial stresses equal to zero). This explains the negative effect of well shutdowns, and even more so the change in the direction of the filtration flow in the downhole part of the formation on the stability of the walls of wells, the operation of which is complicated by sand formation. The maximum difference of the main normal stresses is observed on the well wall, therefore, in order to prevent formation destruction near the bottom, a necessary condition is that the strength properties of rocks correspond to the stresses acting in this zone. When operating wells prone to plugging, it is necessary to limit the depression of reservoir pressure to the maximum permissible value when the material of the filter zone is in an elastic state throughout the volume.

In this paper, the problem of developing a high-viscosity oil reservoir due to the effect of paragravity based on heating the reservoir section between the injection and production wells is considered. The thermal effect on the formation reduces the viscosity coefficient of the oil and increases the mobility of the raw material. The heat transfer equation is solved by the PSSS method. The task is solved in three stages. At the first stage, the oil reservoir is heated, at the second – its exposure, at the third - filtration.

This paper presents a method for calculating the residual metal life of pipelines with crack-like defects. The results of corrosion and fatigue tests of ordinary grade structural steel VSt3sp, widely used in the oil and gas industry, are presented. The work carried out studies on the effect of cathodic polarization on the cyclic crack resistance of VSt3sp steel under the influence of a carbonate-bicarbonate medium.

The purpose of the study is to develop a pumping unit that allows successful injection of coolant into the bottom of the well through a column of hollow rods, followed by oil extraction from the well without lifting equipment. The scientific novelty of the material is based on the possibility of heating the bottom-hole zone of the formation and simultaneous oil production. The technological process of extracting hard-to-recover oil using the proposed installation is based on the following operations: withdrawal of the intake into the annulus, descent of the pump shank into the horizontal shaft; steam injection to the shank and its movement within the bottom-hole zone of the formation - warming up of the near-well area; commissioning of the well with a specially selected technological mode of operation of deep-pumping equipment. The field results of testing the steam injection technology at well No. 3777 of Novo-Sheshminskaya Square are reflected, which showed the fundamental possibility of its application for the successful development of high-viscosity oil deposits. The study also found that for the wide application of the proposed technology, it is necessary to successfully solve a number of tasks, among which the most urgent is the issue of effective thermal insulation of hollow rods in order to minimize heat loss during injection of a special substance. Further development of the proposed technology of pumping production of high-viscosity oil lies in the use of modern materials for the production of underground equipment and improvement of the design of pumping units, aimed at increasing the parameter of the inter-repair period. The proposed technology can be used in the fields of the Volga-Ural oil and gas province, in particular, for example, at the Ashalchinsky field, which will significantly increase the percentage of recoverable reserves characterized as difficult to recover.

The study considers the radial drilling technology, which is used to increase the oil recovery factor in fields in the late stage of development. The composition and technical characteristics of the radial drilling unit are described, recommendations for radial drilling (RD) are given. The paper presents the test results of the technology in the conditions of the Perm Territory and the Republic of Uzbekistan, indicating its high efficiency.

The purpose of this work is to search for an area of effective use of enzyme solutions for the intensification of oil production within fields of various geological structures due to their entry into the final stage of operation, which is characterized by a multiple decrease in oil production volumes, an increase in the water content of products and an increase in the accident rate of the producing well stock. The scientific novelty of the work is based on the empirical determination of various parameters of enzyme solutions that can be successfully regulated during the implementation of injection. Based on laboratory studies of enzyme based complexes, it has been shown that in order to prevent a decrease in enzyme activity in reservoir conditions due to high mineralization and temperature, it is necessary to include chelated compounds in order to limit the influence of metal ions. The optimal concentration of enzyme solutions and surfactants for the minimum value of surface tension has been found out, the achievement of which makes it possible to significantly increase the displacement coefficient, and, consequently, the oil recovery coefficient. To form a qualitative sample of data, the initial geological and commercial material was carefully selected and ranked, which allowed to obtain a minimum error in the calculations. The results of the study of the thermal stability of the enzyme complex showed that the interfacial tension between the solution of the enzyme complex and kerosene is much less than the interfacial tension between seawater and kerosene, which is proof of the thermal stability of the enzyme complex at reservoir temperature. The obtained material can be used both for carrying out various geological and technical measures using enzyme solutions, and for implementing a competent approach to the issue of implementing the optimal chemical composition of the working agent.