scholarly journals TECHNOLOGY PROVIDING SECONDARY PROTECTION METAL STRUCTURES AGAINST CORROSION UNDER AGGRESSIVE IMPACT OF METALLURGICAL PRODUCTION

Author(s):  
Gibalenko O.M. ◽  
◽  
Bocharova O.A. ◽  
Melnik G.О. ◽  

Research is aimed at the formation and development of innovative developments to increase the metal structures corrosion protection, as an important means of ensuring the quality and safety industrial facilities. The method determining the corrosion destruction signs, the procedure of monitoring and carrying out measures to diagnose the technical condition of lattice metal structures according to the level of corrosion hazard were adopted. The nomenclature indicators and control methods (conformity assessment) of determining parameters primary and secondary protection metal designs against corrosion is established. During this study, the lattice structures operational condition loader crane’s girder structure was considered. It is revealed that operation of the crane is carried out in difficult production conditions operating environment’s aggressive influence in combination with considerable dynamic loadings working operations loading technological process, unloading, sorting (averaging) of ore yard’s charge of blast furnace shop. Based on the study structures corrosion condition and operating conditions, measures have been developed to increase the durability ore-grab crane of the reloader. Based on the analysis of the principles of the ISO 9001 process approach, the development and implementation design solutions to extend the structures service life in aggressive environments of metallurgical production. It is proved that the procedure of making constructive and technological decisions, performance works on increase corrosion resistance promotes maintenance conditions of resource saving and technological safety industrial constructions. The principles process is offered to develop and implement design measures to extend the service life of structures in aggressive environments metallurgical production are proposed. Constructive and technological measures to ensure durability in accordance with the requirements of the building structure corrosion risk have been developed, which are determined by the critical indicators metal structures protection in the conditions corrosion influences within their limit values.

Author(s):  
V. I. Ignatov ◽  
V. S. Gerasimov ◽  
N. О. Bogatova ◽  
Z. N. Mishina ◽  
М. S. Mordasova

The necessity of formation of resource-saving ekologiurad-based utilization system of agricultural machinery in agriculture was confirmed by studies conducted in the center FNAC VIM in 2013-2018 years during this period, information was collected about the structure of the charged parts of agricultural machinery (agricultural machinery) going to maintenance of the enterprise with the purpose of recycling. Qualified specialists of repair enterprises were involved in determining the status of parts of the utilized equipment, normative documentation and necessary equipment were used. Terms of operation were determined from the date of purchase until the receipt of the machine to the repair company. The obtained data were subjected to statistical processing in order to determine the effect of the terms of service on the technical condition of these items and determining the number of parts of different groups (in percentage) included in the utilized agricultural machinery, as well as one of the main factors for deciding the feasibility of recycling equipment. The aim of work is justification of alternative ecological oriented intelligent system “Selkhozretsikling” formation for realization of a new strategy of resources use connected with their reuse. The averaged dependences of the change in the coefficient of technical readiness for tractors and combines on their service life are determined. Making an informed decision about the appropriateness of further use the machine (repair or disposal), which is close (or reached) to the limit state depends on the accuracy and timeliness of receiving information about the level of loss of its fitness after a certain service life or operating time. As analysis showed in most farms (52%) the preparation of the components of wastes derived of operation technics allows to use their potential on secondary market. Theoretical works and legislative documents make it possible to carry out the necessary practical measures for the formation of a system for utilization of agricultural equipment.


2022 ◽  
Vol 1049 ◽  
pp. 275-281
Author(s):  
Vladimir Gadalov ◽  
Irina Vornacheva ◽  
Sergey Safonov ◽  
Damir Nuretdinov ◽  
Victoria Alexandrovna Sokolova ◽  
...  

Over a long period of operation, under the influence of corrosion and stresses from the acting forces, metal structures lose their strength. There is a need for their periodic non-destructive testing. The development of new methods is relevant in the field of control of building metal structures, such as bridge structures, structures of building cranes and other mechanical engineering products. The applied methods should be reliable and should not require huge material and labor costs. In this work, informational relationships between acoustic characteristics and parameters of metal microstructure are established. The proposed method can be useful for specialists and experts in the field of monitoring the technical condition of metal products requiring non-destructive testing. The safety of the operated objects depends on the accuracy of the applied criteria, as well as the degree of resource saving due to the full use of the product resource.


Author(s):  
I. V. Oleksyuk

Abstract. Preference is given to cable lines with  cross-linked polyethylene insulation in electrical networks with a nominal voltage of 10 kV during reconstruction of existing and construction of new industrial enterprises. The standard service life of such cables is at least 30 years (subject to the conditions of storage, transportation, installation and operation), and the actual one   is determined by the technical condition of the cable. The service life of a cable line depends on the state of its insulation, the aging of which occurs under the influence of several factors. Conventionally, all factors influencing one or another degree on the cable insulation resource can be divided into thermal, electromagnetic, climatic, mechanical and operational. The most significant reason for the insulation aging  is high temperature, which accelerates the reaction of thermo-oxidative destruction, during which high-molecular polymer compounds decompose. In fact, cables are operated at temperatures below the long-term permissible values, and, therefore, the aging of the insulation is slower, and the actual service life will be longer than the standard. At present, condition of the insulation is monitored with the use of high voltage tests related to destructive testing methods. When designing and operating cable lines, it is necessary to estimate the duration of the actual service life under various operating conditions. In theory, there are several expressions for calculating the service life of a cable line when exposed to temperature, humidity, electric field and aggressive environments, but all of them are not applicable in practice due to the presence of a large number of coefficients whose values are unknown. The paper presents an analytical expression obtained for determining the service life of power electric cables, taking into account the aging of the insulation under the influence of temperature and electric field.


Author(s):  
O. B. Berdnik ◽  
I. N. Tsareva ◽  
M. K. Chegurov

This article deals with structural features and characteristic changes that affect the mechanical characteristics after different service life in real conditions using the example of the blades of the 4th stage of turbine GTE-45-3 with an operating time of 13,000 to 100,000 hours. To study the change in the state of the material under different operating conditions, determine the degree of influence of heat treatment on the regeneration of the microstructure, and restore the mechanical characteristics of the alloy after different periods of operation, non-standard methods were used: relaxation tests on miniature samples to determine the physical yield strength and microplasticity limit and quantitative evaluation of the plasticity coefficient of the material from experimental values of hardness, which allow us to identify the changes occurring in the microvolumes of the material and predict the performance of the product as a whole.


2018 ◽  
Vol 239 ◽  
pp. 06002
Author(s):  
P.V. Chepur ◽  
A.A. Tarasenko ◽  
A.A. Gruchenkova

The problem of the limiting states occurrence in the structures of a vertical steel tank is investigated in this work. To study the SSS of the metal structures of the object, the authors created a numerical model of the RVS-20000 tank in the ANSYS software complex. The model considers the maximum number of elements with their geometry and connections affecting the tank SSS under non-axisymmetric loading, including beyond the elasticity of steel. Dependences between the parameters of intrinsic stiffness of the VST are obtained. The results of the finite element analysis made it possible to develop a technique for assessing the technical condition of the structure with the development of irregular subsidence of the external bottom contour. The proposed technique can be used by both operating and design organizations in making managerial decisions regarding the repair of RVS-20000 subjected to the base subsidence.


2019 ◽  
Vol 114 ◽  
pp. 04005
Author(s):  
Ngo Van Cuong ◽  
Lidiia I. Kovernikova

The parameters of electrical network modes often do not meet the requirements of Russian GOST 32144-2013 and the guidelines of Vietnam. In the actual operating conditions while there is the non-sinusoidal mode in electrical networks voltage and current harmonics are present. Harmonics result in overheating and damage of power transformers since they cause additional active power losses. Additional losses lead to the additional heat release, accelerating the process of insulating paper, transformer oil and magnetic structure deterioration consequently shortening the service life of a power transformer. In this regard there arises a need to develop certain scientific methods that would help demonstrate that low power quality, for instance could lead to a decrease in the electrical equipment service life. Currently we see a development of automated systems for continuous monitoring of power quality indices and mode parameters of electrical networks. These systems could be supplemented by characteristics calculating programs that give out a warning upon detection of the adverse influence of voltage and current harmonics on various electrical equipment of both electric power providers and electric power consumers. A software program presented in the article may be used to predict the influence of voltage and current harmonics on power transformers.


Author(s):  
Graeme G. King ◽  
Satish Kumar

Masdar is developing several carbon capture projects from power plants, smelters, steel works, industrial facilities and oil and gas processing plants in Abu Dhabi in a phased series of projects. Captured CO2 will be transported in a new national CO2 pipeline network with a nominal capacity of 20×106 T/y to oil reservoirs where it will be injected for reservoir management and sequestration. Design of the pipeline network considered three primary factors in the selection of wall thickness and toughness, (a) steady and transient operating conditions, (b) prevention of longitudinal ductile fractures and (c) optimization of total project owning and operating costs. The paper explains how the three factors affect wall thickness and toughness. It sets out code requirements that must be satisfied when choosing wall thickness and gives details of how to calculate toughness to prevent propagation of long ductile fracture in CO2 pipelines. It then uses cost optimization to resolve contention between the different requirements and arrive at a safe and economical pipeline design. The design work selected a design pressure of 24.5 MPa, well above the critical point for CO2 and much higher than is normally seen in conventional oil and gas pipelines. Despite its high operating pressure, the proposed network will be one of the safest pipeline systems in the world today.


Author(s):  
K.O. Kobzev ◽  
◽  
S.A. Vyalov ◽  
E.S. Bozhko ◽  
I.A. Zolotuhina ◽  
...  

This article deals with the problem of operating conditions of guide moving crossbars of hydraulic presses. Based on the study of hydraulic press operation processes, the need to develop and implement measures to ensure reliable and trouble-free operation of the press was identified. The conclusion justifies the idea that if these technical solutions are implemented, the service life of hydraulic presses will increase


Author(s):  
A.V. Golenishev ◽  
A.V. Nadezkin ◽  
M.E. Starchenko

Рассматриваются подходы по определению пороговых значений концентрации продуктов износа в отработанном цилиндровом масле, характеризующие переход объекта диагностирования судового крейцкопфного дизеля из одного технического состояния в другое. Показано, что существующие методики не учитывают индивидуальные особенности и техническое состояние деталей цилиндропоршневой группы. Предложено для решения задачи их трибодиагностики использовать разработанную имитационную модель, позволяющую провести моделирование процесса изнашивания цилиндровой втулки и поршневых колец судового дизеля и на основании полученных расчетов определить концентрацию продуктов износа поступивших в отработанное цилиндровое масло при различной скорости изнашивания трущихся деталей. Данные о фактической концентрации продуктов износа в отработанном цилиндровом масле в дальнейшем соотносятся с результатами моделирования, что позволяет оценить техническое состояние деталей цилиндропоршневой группы двигателя. Представлены результаты моделирования по определению пороговых значений концентрации продуктов износа в отработанном цилиндровом масле, характеризующее переход судового дизеля из исправного в несправное техническое состояние. Даны практические рекомендации по выбору пороговых значений содержания продуктов износа в отработанном цилиндровом масле для различных типов судовых крейцкопфных дизелей и условий их эксплуатации.The article examines approaches to determine the threshold values of the concentration of wear debris in used cylinder oil that characterize the transition of a ship crosshead diesel engine unit under test from one technical condition to another. It is shown that the existing methods do not take into account the individual characteristics and technical condition of the parts of the cylinder-piston group. To solve the problem of tribodiagnostics, it is proposed to use the developed simulation model, which allows modeling the wear process of the cylinder bushing and piston rings of a marine diesel engine and, based on the obtained results, determining the concentration of wear products issued in the used cylinder oil at different wear rates of the moving parts. The data on the actual concentration of wear products in the used cylinder oil are subsequently correlated with the simulation model results, which makes it possible to evaluate the technical condition of the parts of the engine cylinder-piston group. The article presents the results of modeling of threshold values determination of the concentration of wear products in used cylinder oil, that measure the transition of a marine diesel engine from a working condition to a malfunctioning technical condition. Practical recommendations are given on choosing threshold values for the concentration of wear products in used cylinder oil for various types of marine crosshead diesel engines and their operating conditions.


Sign in / Sign up

Export Citation Format

Share Document