Ensuring the strength and stability of the tank wall during repairs by installing rigid frames

2021 ◽  
pp. 152-165
Author(s):  
Артем Николаевич Задумин ◽  
Евгений Григорьевич Ильин ◽  
Михаил Владимирович Лиховцев ◽  
Алексей Александрович Катанов
Keyword(s):  
Computer Modeling ◽  
Strain State ◽  
Mutual Influence ◽  
Tank Wall ◽  
Stress Strain ◽  
Stability Calculation ◽  
Actual Structure ◽  
Repair Work ◽  
Stress Strain State ◽  
Cutting Out

Устранение дефектов металла и сварных швов стенок вертикальных цилиндрических резервуаров возможно методом вырезки и замены удаленных фрагментов ремонтными вставками с использованием рам жесткости. При этом в нормативных документах отсутствуют методики расчета таких усиливающих элементов и собственно конструкции стенки резервуара с данными элементами. С целью оценки прочности и устойчивости стенки резервуара и рамы жесткости во время проведения ремонтных работ выполнено компьютерное моделирование и проведены расчеты напряженно-деформированного состояния указанных металлоконструкций. В рамках исследования рассмотрены основные российские и зарубежные нормативные документы, регламентирующие нагрузки и методики расчета устойчивости стенки резервуара, проанализированы публикации, посвященные расчету устойчивости стенки резервуара с применением компьютерного моделирования. Приведены результаты компьютерного моделирования и расчетов на прочность и устойчивость в зависимости от снеговой и ветровой нагрузок. По итогам выполненных работ сделаны следующие выводы: 1) расчеты должны учитывать ветровую нагрузку, действующую под углом 40° к вырезаемому фрагменту; 2) допустимые размеры одной вставки не должны превышать габариты одного листа пояса резервуара; 3) не рекомендуется одновременная вырезка и замена более чем одного фрагмента; 4) при необходимости возможность одновременной вырезки проемов в двух и более местах должна определяться расчетом, учитывающим взаимное влияние количества, расположения и размеров проемов на напряженно-деформированное состояние стенки резервуара и рам жесткости. Elimination of metal defects and welds in the walls of vertical cylindrical tanks is possible by cutting out and replacing the removed fragments with repair inserts using stiffening frames. At the same time, there are no methods for calculating such reinforcing elements and the actual structure of the tank wall with these elements in the regulatory documents. In order to assess the strength and stability of the tank wall and the stiffening frame during the repair work, computer modeling was performed and the stress-strain state of these metal structures was calculated. Within the framework of the research the main Russian and foreign normative documents regulating the loads and methods of tank wall stability calculation are considered; the publications devoted to the tank wall stability calculation by means of computer modeling are analyzed. The results of computer modeling and calculations for strength and stability depending on snow and wind loads are presented. Results of the research performed were used to make the following conclusions: 1) calculations should take into account the wind load, acting at an angle of 40° to the section to be cut out; 2) the allowable dimensions of one insert should not exceed the dimensions of one sheet of the tank ring; 3) simultaneous cutting out and replacement of more than one section is not recommended; 4) if necessary simultaneous cutting of openings in two or more places should be determined by calculation, taking into account the mutual influence of the number, location and sizes of openings on the stress-strain state of the tank wall and stiffening frames.

scholarly journals The stress-strain state simulation for the auger-boring machine’s support-guide system

2021 ◽  
Vol 315 ◽  
pp. 03008
Author(s):  
Aleksei Khoreshok ◽  
Leonid Mametyev ◽  
Oleg Lyubimov ◽  
Andrey Kuznetsov ◽  
Yunliang Tan
Keyword(s):  
Computer Modeling ◽  
Strain State ◽  
Technical Solution ◽  
Mining Operations ◽  
Stress Strain ◽  
Stress Strain State ◽  
Guide System

The article deals with a number of important aspects of the aggregate-modular type auger-boring equipment creation, as an integral part of the range of tunneling complexes for mining operations and laying horizontal and slightly deviated holes for various purposes. The importance of improving the support and guide systems, characterized by a variety of configurations and sizes, a large number of elements for various purposes and with different responsibility degree, is noted separately. In this regard, the possibility of flexible refinement of the complexes configuration for specific boring conditions with the verification of each applied technical solution by computer modeling remains relevant. The ways for a new constructive solutions creating are outlined.

scholarly journals Assessment of the mutual influence of deformation-strength characteristics of the fastening system elements

2019 ◽  
Vol 123 ◽  
pp. 01006 ◽  
Author(s):  
Iryna Kovalevska ◽  
Zenon Pilecki ◽  
Oleksandr Husiev ◽  
Vasyl Snihur
Keyword(s):  
Mine Working ◽  
Strain State ◽  
Mutual Influence ◽  
Strength Characteristics ◽  
Stress Strain ◽  
Load Bearing ◽  
Stress Strain State ◽  
Operation Modes ◽  
Mine Workings ◽  
Rigid Element

The degree of influence has been determined of diversified deformation-strength characteristics of load-bearing elements in the fastening system of the preparatory mine workings, while maintaining them in a laminal massif of soft rocks. The analysis has been performed of multivariate computational experiments of the stress-strain state of the load-bearing elements of the fastening system in the preparatory mine workings from the position of the mutual influence of their deformation-strength characteristics and the support loading as a whole. An analysis is represented of the mutual influence of the operation modes of the mine working support elements between themselves and the fastening system as a whole; it has been studied the stress-strain state of the mine working fastening system with a central hydraulic prop stay, as well as a significant increase in reliability of the support performance has been analysed and determined. The tendency has been substantiated of minimizing the load on the mine working fastening system – increasing the coherence of the diversified operation modes of fastening elements by enhancing preferentially the yielding property of the rigid element. The application has been substantiated of the central yielding prop stays of the strengthening support of a frame in case of intensive rock pressure manifestation in the zone of the stope works active influence.

scholarly journals On extending the life of nuclear reactors

2021 ◽  
Vol 2131 (2) ◽  
pp. 022030
Author(s):  
A V Kramskoi ◽  
Y G Lyudmirsky ◽  
M E Zhidkov ◽  
M I Kramskaia
Keyword(s):  
Service Life ◽  
Base Metal ◽  
Strain State ◽  
Mutual Influence ◽  
Nuclear Reactors ◽  
Test Procedure ◽  
Reactor Vessel ◽  
Stress Strain ◽  
Stress Strain State ◽  
Additional Service

Abstract To extend the service life of nuclear reactors, witness samples from the shells of the core of the reactor vessel are placed in their core. According to the requirements in force in the industry, the reference samples are loaded into the reactor plant unloaded up to the design stresses. This can lead to a biased assessment of the possible extension of the reactor’s life. In connection with the above, in order to assess the mutual influence of operating factors and the stress-strain state of the base metal and welded joints on embrittlement, the reference specimens must be loaded with a force that causes the maximum possible stresses in the specimens during the operation of the reactor. On the basis of domestic and international experience, a test procedure, design and loading scheme for compact witness samples are proposed for modeling and assessing the mutual influence of operating factors and stress-strain state on the object under study (VVER power reactor vessel). For VVER RPVs, the duration of the additional service life should be confirmed by the justification that by the end of the additional service life, the fracture toughness values of the base metal and metal of the welded seams located in the irradiation zone will allow without destruction to withstand all operational and emergency loads, as well as loads at hydraulic tests.

scholarly journals Development of a Nonlinear Dependence for Determining the Stress-Strain State of the Pipeline-Composite Bandage System

2021 ◽  
Vol 248 ◽  
pp. 04024
Author(s):  
Robert А. Ramazanov ◽  
Igor F. Kantemirov ◽  
Denis A. Gulin ◽  
Indira F. Makhmudova ◽  
Zulfiya F. Ismagilova
Keyword(s):  
Polymer Composite ◽  
Strain State ◽  
Polymeric Materials ◽  
Polymer Materials ◽  
Nonlinear Dependence ◽  
Technical Diagnostics ◽  
Stress Strain ◽  
Repair Work ◽  
Industrial Enterprises ◽  
Stress Strain State

The range of applications of polymeric materials in the oil and gas industries is expanding every year. For example, at present, a number of industrial enterprises are engaged in the production of various tape polymer composite structures that are used to repair pipelines. They are widely used due to the significant advantages of polymeric materials over steel such as low costs, low weight, corrosion resistance and strength. Moreover, most of the operated pipelines are about to reach their standard service life. In the course of technical diagnostics, a significant number of defects of mechanical origin from external influences are constantly revealed. Repair work on pipelines must fully restore the bearing capacity of the site. Therefore, the use of polymer materials for pipeline repair is an important task. Here, we propose to use polymer composite bandages, which will increase the overhaul period. However, a coherent methodology for choosing a material and calculating the required thickness of this structure is not available in the literature, and, therefore, the purpose of this work was to develop such a methodology, as well as to assess the stress-strain state of pipeline-bandage systems. The method presented in this work takes into account the possible anisotropy of the shroud material in the longitudinal and transverse directions and the possibility of plastic deformation of the pipeline material in the annular direction. This work is based on the following assumptions: (a) bilinear dependence of stress on deformation for steel; (b) plastic deformations of the band material are absent; and (3) absolute adhesion between the pipeline and the band. The paper presents the analysis of the market of polymeric materials for pipeline repair, their key properties, and the minimum thickness of the band made of these materials was calculated for various values of the stress concentration coefficient.

scholarly journals Computer modeling of the stress - strain state of a linear friction welded disk

2015 ◽  
Vol 8 (6) ◽  
pp. 61-64
Author(s):  
V. Bychkov ◽  
◽  
A. Pautov ◽  
A. Medvedev ◽  
◽  
...  
Keyword(s):  
Computer Modeling ◽  
Strain State ◽  
Stress Strain ◽  
Stress Strain State ◽  
Linear Friction

scholarly journals Investigation of the Tubular and Cylindrical Billets Stamping by Rolling Process with the Use of Computer Simulation

2021 ◽  
Author(s):  
Viktor Matvijchuk ◽  
Andrii Shtuts ◽  
Mykola Kolisnyk ◽  
Ihor Kupchuk ◽  
Iryna Derevenko
Keyword(s):  
Computer Simulation ◽  
Computer Modeling ◽  
Strain State ◽  
Cold Deformation ◽  
Rolling Process ◽  
Stress Strain ◽  
Workpiece Material ◽  
Deformation Curves ◽  
Stress Strain State ◽  
Sound Management

Forming of blanks during stamping by rolling (RS) is possible according to technological schemes of deposition, landing, direct and reverse extrusion, distribution and compression, etc. Controlling the relative position and shape of the deformed tool allows you to control the direction of flow of the workpiece material and the nature of its formation, as well as the stress-strain state of the material. The complexity and versatility of RS processes necessitate computer modeling for sound management of basic technological parameters.Physical experimental as well as computer modeling of the RS process in the DEFORM-3D software package was performed in the work.According to the results of computer simulation, the distribution of deformation components, stresses and temperatures in the deformed workpiece area was obtained, and using the Cockroft-Latham criterion, the destruction of metals during cold deformation was also predicted.Physical modeling of the SR process on lead blanks confirmed the nature of their deformation, obtained by computer simulation. And the analysis of the stress-strain state of the material based on the results of measurements of the deformed grid confirmed the validity of the appointment of boundary conditions in computer simulation.This approach is suitable for modeling by the method of SR of any metal models, for which it is necessary to know their mechanical characteristics, including boundary deformation curves.

scholarly journals The stress-strain state of the tank on soil foundation with local inhomogeneity

2019 ◽  
pp. 96-101 ◽  
Author(s):  
Alesya A. Gruchenkova ◽  
Aleksandr A. Tarasenko
Keyword(s):  
Strain State ◽  
Local Area ◽  
Tank Wall ◽  
Local Inhomogeneity ◽  
Technical Documentation ◽  
Stress Strain ◽  
Stress Strain State ◽  
Zone Of Influence ◽  
Soil Foundation

This article aims to numerically investigate the stress-strain state of the tank at the appearance a local area of inhomogeneity in the soil foundation. We have established the size of the zone of influence of the inhomogeneity area of the base on the work of the tank wall. Also, we have formulated proposals to adjust the requirements of the Russian regulatory and technical documentation.

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