The experimental evaluation of the power criterion for the metal fracture of the reserve and the long operated drill pipes was carried out. The conditions under which, during tripping operations, the failure of explored drill pipes, containing external or internal transverse annular cracks are possible. An interrelation between the depth of critical external or internal transverse annular cracks in drill pipes with the weight of the drilling string is considered, taking into account the influence of dynamic loads during tripping operations. It is shown that internal transverse annular cracks in lowering operating drilling strings at depths of more than 1400 m are more dangerous than external ones, while at depths up to 1400 m, external cross-sectional circular cracks are more dangerous.

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A new efficient CNG module design for the transportation of natural gas by sea is proposed and substantiated. A mathematical model for determining the technical and economic parameters of a movable pipeline module, which is designed for transporting natural gas in a compressed state and consists of a frame structure, the dimensions of which correspond to the 40-foot marine container size and a pipe coil is described. To facilitate construction, it is proposed that a large portion of the coil be made in the form of a two-layer composite construction. The inner layer consists of standard steel tubes or adapters, and the outer layer is fiberglass wound on them. On the basis of the mathematical model an algorithm and a program were compiled, which allowed to determine the technical and economic parameters of the movable pipeline module. The results obtained for the Caspian region are analyzed.

All methods of combating the flooding of populated areas are directly related to the execution of significant volumes of earthworks, the construction of special structures, and therefore require comprehensive analysis and substantiation and the selection of the most economically feasible and affordable project options during design.But analyzing the main methods of protecting the territory of settlements from flooding, it should be noted that even with their optimal use, the problem of flooding territories due to river tributaries remains. Therefore, it is worth focusing attention on the search for a technical solution that would make it possible to pump water from the tributary to the river without using expensive, complex in design and energy-consuming equipment. One of the promising solutions is the use of automatic gateways.The purpose of the work is to study the hydrodynamic parameters of the proposed design of the self-acting lock to prevent flood spills.The design of a hydrotechnical structure (self-acting sluice to prevent flood spills) is proposed, which is designed to prevent flooding of territories due to river spills and can be used to regulate the water level in hydraulic systems. It is shown that the use of the developed structure will make it possible to significantly reduce the negative consequences of possible flood spills in the territories.A three-dimensional model of the self-acting sluice was developed in the SolidWorks program to confirm its performance and study the hydrodynamic parameters of the self-acting sluice. The simulated simulation of the proposed design of the ejector pump in the FlowSimulation software module confirmed its efficiency and made it possible to determine the distribution of pressures and fluid movement speeds in it. It was established that the flow rate of the liquid flowing through the cross-section of the pipeline for water intake from the tributary is 0.055 m3/s at a river flow speed of 3 m/s.