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Keyword: «stress-strain state»

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Today is not uncommon carry out works in open hole drilled oil and gas wells, such as the fight against zones A, test prospective horizons at neftegazosoderzhanie installing a cement bridge and others. Work submersible equipment in the open hole is associated with very severe conditions as a consequence of which pays great attention to the reliability of the equipment and reduce the probability of accidents of work. Packer-anchor complex is the most crucial node in the complexes for the above work in the open hole. To ensure a more reliable and less emergency work in the open borehole must be continuous improvement packer and anchor of the complex on the basis of the development of scientific and theoretically base. The main objectives of the below article is: the development of mathematical models based on the finite element analysis, preparation of loading schemes packer and anchor equipment and their subsequent decision to the definition of places of critical loads in the critical nodes and the complex as a whole, as well as making recommendations for the subsequent strength calculations and develop conceptually new equipment based on the knowledge and relationships.
The article considers the instrumental survey methods and their peculiarities for underwater pipeline crossings (UPC) located in a sharply continental climate. The following instrumental survey methods are described: profile sounding using the OKO-2 GPR, examination of the Lena River bottom in the area of the underwater crossing of the main gas pipeline (MGP) using Hydra 500E side-scan sonar, determination of the actual planned-high-altitude position of the floodplain part of the underwater gas pipeline employing the RD-8000 line locator. It is shown that there is a practical set of equipment that makes it possible to perform planned and real-time monitoring of the state of the UPC almost all year round, despite the unfavorable climatic conditions and the extension of some UPCs in Central Yakutia.
The paper considers the possibility of using a local low-temperature loading method during acoustic emission control of hazardous production facilities in order to establish the degree of danger of crack-like defects. This method is based on the creation of a local stress-strain state, realized by the effect of a gradient temperature field on an object using carbon dioxide in the form of "dry snow". Signals from acts of acoustic emissions emanating from the top of an artificially applied crack on a thin-sheet plate were processed and investigated. The theoretical values of the stress intensity coefficient for a defect under the influence of local low-temperature loading are calculated. It is shown that with a local low-temperature loading method, a power-law dependence of the number of acoustic emission acts on the stress intensity coefficient is observed.
The paper considers the possibility of using local low-temperature loading during AE control. This method is based on the creation of a local stress-strain state, which is formed when a gradient temperature field is applied to an object using carbon dioxide in the form of "dry snow". Signals from acts of acoustic emissions emanating from the tip of an artificially applied crack on a thin-walled plate were processed and investigated. Theoretical values of the stress intensity coefficient for a defect under local low-temperature loading are calculated. It is shown that with the method of local low-temperature loading, a power dependence of the number of acts on the stress intensity coefficient is observed.
A considerable length of main gas pipelines (MGP), a variety of natural-climatic, geocryological conditions and impacts determine the need to allocate sections, in which the development of dangerous natural processes and impacts on MGP is predicted. For such sections requirements on protection of MG from dangerous influences should be formulated, and also measures on monitoring of development of dangerous processes, changes of a spatial position of the pipeline and an estimation of its stress-strain state (STS) should be established. In the article methodological bases of calculated forecasting and classification of pipeline sections in the zones of development of geocryological engineering processes were developed: – integrated methodology for the analysis and prediction of the stress-strain state of MGP in the areas of development of dangerous geocryological processes; – the principles of classifying the sections according to the predicted hazard; – criteria for assessing the impact of natural processes on the pipeline and their ranking in terms of significance levels; – classification of MG sections according to the predicted hazard.