Вплив якості спорудження нафтопроводів на їх експлуатаційну надійність

Abstract

Дисертацію присвячено розробці заходів підвищення рівня якості спорудження нафтопроводів для підвищення їх експлуатаційного ресурсу. Запропоновано метод оцінки якості функціонування нафтотранспортної системи, який дозволяє за характером зміни показників якості визначити залишковий ресурс нафтопроводу. Проведено експериментальні дослідження залежності зміни втомних напружень границі плинності матеріалу труб в залежності від циклічного навантаження з метою встановлення характеру зміни напружень від числа циклів навантаження для різних умов експлуатації сталі. Встановлено доцільність і необхідність консервації нафтопроводу при умовах неможливості введення його в експлуатацію після завершення будівництва.

Диссертация посвящена разработке мероприятий повышения уровня качества сооружения нефтепроводов для повышения их эксплуатационного ресурса. Предложен метод оценки качества функционирования нефтетранспортной системы, который позволяет по характеру изменения показателей качества определить остаточный ресурс нефтепровода. Проведены экспериментальные исследования зависимости изменения усталостных напряжений границы текучости материала труб в зависимости от циклической нагрузки с целью установления характера изменения напряжений от числа циклов нагрузки для разных условий эксплуатации постоянные. Установлена целесообразность и необходимость консервирования нефтепровода при условиях невозможности введения его в эксплуатацию после завершения строительства

The research work consists of entry, four sections, general conclusions, list of the used literature and additions. Quality of oil pipelines building is a main scientific problem and for its solving permanent integration of achievements is necessary. The quality of an oil pipeline building is properties, which determine the degree of its accordance to the requirements, that are given. It is already clear from it it is comparative common determination many-sided nature of notion of quality, that opens up in a number of such properties how firmness, durability, impermeability, corrosive firmness, faultless, longevity and in., is If to take into account that research of every properties separately or by a group requires development of the special mathematical and physical theories, complication of problem of quality of main oil pipelines becomes clear. In the first section the analysis of the state of the oil transport system of Ukraine is made, qualities of building of oil pipelines, review of literary sources after direction of research, what a purpose and tasks of researches is formulated on the basis of. The thermodynamic method of analogy is worked out for avaluating quality in functioning of oil transport system, which allows to estimate a residual resource of an oil pipline by the type of the qualities change. The second section is devoted to analytical research of prognostication of reliability and longevity of the pipeline systems due to quality of their building. The estimation method of quality functioning of the gas-transport system allows to define the remaining resource of oil pipeline, is offered by the character of change of indexes of quality. In the third section quality of every building is determined by quality of the materials expended in building, and quality building and installation the works of. On the stage of building of oil pipeline the definite level of quality, which determines reliability of functioning of the system, is mortgaged. In the process of exploitation there is assimilation of quality, that is the dispersion related to the senescence of building and materials, that results in the decline of level of reliability. The decline of level of reliability during exploitation of the system results in growth of frequency of refusals and in the end determines the resource of the technical system. Consequently, for determination of resource it is necessary to set the initial level of reliability, character of its falling during exploitation and granitsyo after which exploitation of the system inadvisable as a result of high intensity of refusals. The mechanical tests of steel pipe for measure estimation of degradation of its properties for the period of exploitation of oil pipeline Odessa-Brody are considered.Тhe mathematical model of unstationary motion of petroleum is created in an oil pipeline, caused by the jumping changes of serve of petroleum in an oil pipeline, which it is set on the basis of, that pressure fluctuations in an oil pipeline within the limits of unstationary process take place in the range of frequencies 0,4 - 0,6 1/s, and amplitude of pressure fluctuations makes 0,1 - 0,5 MT. Experimental researches of dependence of change of tireless tensions of border of fluidity of material of pipes are conducted depending on the cyclic loading with the purpose of establishment of character of change of tensions from the number of cycles of loading for different external environments permanent. The fourth section is devoted to research of influencing of dynamics of change of mechanical descriptions of steel on the resource of pipeline. Optimization of process of technical maintenance of building of the naftotransportnih systems foresees abbreviation of expenditures on transporting, that, in the end, results in the decline of his prime price. Consequently to the questions of development of rational strategies of technical maintenance of elements of oil pipeline and estimation of remaining resource of the systems of the distant transporting of oil and gas considerable attention is spared. Expedience and necessity of canning of pipeline is set subject to the condition impossibility of introduction of it in exploitation after completion of building. For 6 years of exploitation of area of pipeline, that was not subject to canning, a remaining resource went down on comparison with forecast on 10,4 %. In the case of canning of pipeline in the environment of limestone milk on this period a remaining resource went down on comparison with forecast on 6,5 %, that saving of pipe steel in the environment of limestone milk testifies to high quality. All reliability indexes, in the end, rely on the technical state of linear part of oil pipeline, stabilities of its structure, term of saving of values of parameters of the technical state in the set scopes. Exceeding by even one structural parameter of maximum value means violation of integrity or working fitness of oil pipeline. Frequency (probability) of violation of working fitness of oil pipeline, that is frequency of refusals during exploitation, determines the level of his faultless. The increase of frequency of refusals worsens the indexes of repair fitness and negatively affects longevity of linear part of naftopovodou. On the base of research results a complex field mothodology is developed, which is called “Prediction of cracks growth in welding joints of pipelines under pressure including the residual tension”.