Different Periods Of Operation Research Articles

ИССЛЕДОВАНИЕ ФИЗИКО-ХИМИЧЕСКИХ И ПРОТИВОИЗНОСНЫХ СВОЙСТВ МОТОРНЫХ МАСЕЛ ПО ЗАВЕРШЕНИИ ПРОЦЕССА ЭКСПЛУАТАЦИИ

There is given the study of viscous properties of engine oil, depending on the temperature before and after change on modern domestic gasoline and diesel cars, the determination of spectral characteristics and X-ray fluorescence analysis of wear particles after mileage. The degree of viscosity of semi-synthetic oils of two types is estimated. The oils were cooled and heated up to 150 °C. A digital viscometer was used, the dynamic viscosity of all oils decreased with increasing temperature, which is associated with oxidation in waste oil. To assess the effect of motor oil on engine operation, IR spectrometric analysis is performed and the thickness of the lubricating film is determined. The test results showed a qualitative and quantitative change in the characteristic frequencies of the new engine oil and the spent one after 10,000 km. X-ray fluorescence analysis makes it possible to analyze wear products and determine which mechanism in the engine is most susceptible to wear. Lines have characteristic absorption frequencies and indicate a change in physico-chemical properties of oil in the engine. An increase in contamination and in the viscosity of used oils is associated with the presence of impurities formed during the oxidation and polymerization of the base oil. It is necessary to increase the number of samples and sampling during different periods of operation so that you can verify the same effect throughout the entire engine operation. The results obtained indicate that these methods can be used to analyze and control the mode of operation of oils in the engine, allowing to determine the wear and further apply appropriate additives to the oil to improve performance properties.

Evaluation of Spatiotemporal Transit Accessibility: Weighted Indexing Using the CRITIC‐MCDM Approach and Performance Gap Analysis

Transit performance is greatly influenced by its accessibility, which considers the spatial distribution of transit facilities with different periods of operation. The present study analyzes the spatiotemporal variation in transit accessibility and proposes a modification to enhance the evaluation process. The proposed modification involves assigning weighted indexing to the public transport coverage index (PTCI) using the CRITIC (criteria importance through intercriteria correlation) MCDM technique. The indicators exhibit temporal and spatial variations based on network and operational characteristics, with temporal variations relying on the number of scheduled transits and spatial variations influenced by the network and other operational attributes. The case study conducted in Surat, India, reveals that areas such as the city center and inner fringe have a higher concentration of scheduled transits and bus stops. However, demand fulfillment, measured by the offered seat capacity per population, is relatively low in most zones. To prioritize areas for resource allocation and policy implementation, the use of “RAdial REferenced Scatter QUAdRant (RARE SQUARE) Performance” charts are developed, which provide a straightforward tool to validate findings. The study highlights a low relative transit demand in the city, resulting in a mode share of approximately 2.5%.

Assessment of the transport capabilities of inland waterways

The article is devoted to the assessment of the transport capabilities of inland waterways on the example of the Siberian region. As the main indicator of this assessment, the authors propose the product of the coefficient of the class of the depth of the ship's course of the river for the period of its operation. The introduction contains the normative documents on the basis of which the proposed methodology is based. It is proposed to calculate the resource of rivers according to two options: in the first – the guaranteed depth of the ship's course is used, in the second - the change in the class of the depth of the ship's course of the river during the entire navigation is taken into account. Based on the proposed methodology, calculations of the resources of the four main Siberian rivers were made. Thanks to this indicator, it became possible to calculate and compare the resources of rivers with different periods of operation and different depths of the ship's course. The Lena River has the least resource in the region, since its upper reaches are sharply limited by the depth of the ship's passage, and the lower reaches by the period of operation.

ВЛИЯНИЕ УСЛОВИЙ ФОРМИРОВАНИЯ ВОДОНЕФТЯНЫХ ЭМУЛЬСИЙ НА ИХ СТРУКТУРНО-МЕХАНИЧЕСКИЕ СВОЙСТВА

Abstract. The Republic of Kazakhstan is one of the leaders in the production of hydrocarbons. However, the oil produced in Kazakhstan, especially from the Severnye Buzachi oil and gas field, has a high viscosity and, therefore, belongs to the category of unconventional resources with a high content of metals associated with asphalt-resinous components. This problem is common to all countries producing oil in the Caspian basin. Analysis of the development of the Severnye Buzachi oil and gas field indicates a sharp increase in water availability at the initial stage of development, which is due to an excessively large difference in the rheological characteristics of reservoir oil and water. As a result, an oil-water emulsion is formed at the bottom of the well and in the trunk, which can acquire many different states with various physical, mechanical and technological properties. A significant number of works have been devoted to the study of the properties of oil-water emulsions. Oil in the Caspian basin is characterized as viscous and heavy with a high content of metals, especially vanadium and nickel, which interact in oil with asphalt-resinous components. These properties of oil reduce oil recovery. These properties and methods of optimizing oil production were considered on the basis of the North Buzach oil and gas region of the Republic of Kazakhstan. The structural and mechanical properties of water-oil emulsions of crude oil have been experimentally studied. Based on the measured parameters, the shear stress values were calculated at the shear rate of the walls, and then flow curves were constructed for different temperatures and oil-water ratios. As a result, the regularities of changes in rheological properties depending on the water content and temperature were revealed and a formula was obtained that allows determining the values of the effective viscosity complex of oil-water emulsions. Based on the results obtained, optimization of technological modes of oil preparation for further transportation and processing in different periods of operation can be carried out in this area. Keywords: oil-water emulsion, demulsification, rheology, heavy oil, oil and gas field, Northern Buzachi, resins, asphaltenes, emulsifier, reagent, turbulence, flow, experimental studies, viscosity.

Анализ результатов проведенных геолого-технических мероприятий и их влияние на компонентоотдачу

The article considers the results of carrying out geological and technical measures on the wells of the Astrakhan gas condensate field. The main objectives of this study are to establish the relationship between the tectonic structure of the AGCF and the porosity and reservoir properties of the reservoir rocks that make up this field, as well as the description of oil and gas potential based on the lithological and stratigraphic features of the field. The results 
 of the calculation of the economic efficiency of the results of geological and technical measures are given. At the field in different periods of operation, various technologies were used to increase the productivity of wells. Geological and technical measures were carried out at the AGCF wells using a set of coiled tubing during development after drilling and during the development after a workover of wells from the machine at the wells of the existing well stock. Based on the results of the subsoil user's assessment, it was found that for all wells, as a result of geological and technical measures, a positive effect was obtained, expressed in an increase in production rate at the same working pressure. The results of the hydrochloric acid treatment were summed up; the average increase in production rate for complex treatments is indicated; the final average increase in debit is indicated. The efficiency of the hydrochloric acid treatment carried out for the first time is emphasized; the average increase in production rate based on the results of hydrochloric acid treatments is indicated. Conclusions were drawn about the reservoir properties of reservoir rocks of the field and the degree of homogeneity of the lithological composition, on the basis of which information was obtained on the economic efficiency of the experiments, the use of which is possible only after the development of modern technologies for influencing the reservoir.

Changes in the kinematic viscosity of engine oil during the operation of marine diesel engines

A prerequisite for the long-term and safe operation of marine diesel engines is the high quality of operational materials, which include engine oils and coolants. The required quality of operational materials is ensured by the introduction of additives into their composition, which are now increasingly used as nanoparticles. During operation, as a result of the destruction of additives, the operational properties of coolants and engine oils deteriorate. The conducted studies allowed us to evaluate the change in the lubricating ability of engine oils of two brands that are used in marine diesels during operation. As a characteristic of the lubricating ability of the oil, its kinematic viscosity was used. The experimental determination of the kinematic viscosity of engine oil samples having different periods of operation, and the subsequent mathematical processing of the experimental results made it possible to determine the dependencies characterizing the change in the kinematic viscosity of engine oil during its operation. The research results confirm the possibility of scientific justification for extending the use of marine diesel engine oils, which reduces operating costs and increases the environmental safety of marine diesel engines.

Research of wear resistance of a covering of shafts of the turbocharger of the diesel engine restored by means of a gas-dynamic spraying

The analysis of tribological researches on the most perspective way of restoration of a primary resource of engines by means of a gas-dynamic spraying is resulted in article. It was found that to reduce the coefficient of friction and increase the wear resistance of the coating is theoretically justified the use of copper-zinc powders brand C-01-11, applied by gas-dynamic spraying. It is established that the physical and mechanical properties of the coatings (roughness, microhardness, friction coefficient) on the restored turbocharger meet the requirements of the manufacturer. The coefficient of friction in the connection, the rotor shaft (reduced powder with copper and zinc), with a plain bearing (made of tin-lead bronze Bros - 10 - 10) is 20 % less than in the connection where the rotor shaft is made of steel 40. The total wear in the bearing assembly with the restored gas-dynamic sprayed rotor shaft is 20 % lower than in the assembly where the rotor shaft is restored by the basic technology. The technology of restoration of a surface of a shaft of a rotor of the turbocompressor, under the bearing of sliding (gas-dynamic spraying) which increases its resource by 23 % in comparison with basic technology of repair of a shaft of a rotor is developed. This allows you to increase its operating time with the established regulatory and technical documentation for overhaul of the engine. A stand for testing diesel turbochargers with recovery technology has been developed, which allows to determine the parameters and characteristics of diesel engine turbochargers in different periods of operation, running-in and adjustment. Tests on the stand showed that turbochargers with restored rotor shafts according to the proposed technology after 2000 operating hours increase all performance by 13 % more than turbochargers repaired by the basic technology. Operational tests have shown that turbochargers repaired using the proposed technology have an operating time of 989 moto-hours more than turbochargers repaired with existing technology

Анализ причин повреждений и отказов судовых валопроводов

The paper highlights the problem of a ship shaft line failure, which entails significant economic losses, because most vessels of the Russian fleet are equipped with a shaft line. A large number of domestic and foreign works are devoted to studying the causes of damage and failures of ship shafting. The complexity of collecting, systematizing and analyzing statistical data on breakdowns and damages of shafting lies in the fact that the data refer to different periods of time, different periods of operation and types of ships, and are also contained in various sources. There has been considered the approach to systematization of modern statistical data on damages and failures of ship shafting elements collected on the basis of defect-technological lists of the Astrakhan shipyards and from other sources. Information on breakdowns of ships, their elements and ship shaft lines within 2010 - 2019 provided by the Russian River Register of Shipping is given. The analysis of accidents on ships of the class of the Russian Maritime Register of Shipping. The places of occurrence and the nature of the propeller shaft cracks have been established, which makes it possible to assess the nature and magnitude of the destructive loads, as well as the real safety margins. The general classification of the location of the propeller shaft cracks in the order of the frequency of their occurrence is given. There have been shown the results of the analysis of defect-technological lists, which make it possible to establish the causes of ship shafting failures, which led to emergency repair, and the most common defects identified during the scheduled dock repair of ships. The influence of the diameter of propeller shafts on the nature and size of defects, as well as the frequency of their manifestation, is estimated. Based on the results of the analysis, certain measures have been proposed to reduce the number of accidents in shafting of projected vessels, and the most promising directions for improving the already developed structures of shafting in operation are outlined. The results of the analysis are in addition to the ongoing research and development work to improve the reliability of ship power systems.

ОЦІНКА ЕКОНОМІЧНОГО ПОТЕНЦІАЛУ РЕГІОНІВ ТА ЇХ МОЖЛИВОСТЕЙ

Based on the analysis of methods for quantitative assessment of the economic potential of regions in the context of available resources, the direction of this process is systematized in the following areas: economic-geographical, production, demographic, information and macromodels. The necessary characteristics of the economic potential of cities and settlements, including the territory, population, production, investments and loans have been formulated. They reveal the main components of existing opportunities, which make it possible to create a basis for an objective assessment of the potential for socio-economic improvement, its acceleration and increase in effectiveness. For a wide coverage of the directions of changes and reflecting their dynamics, it is proposed to take into account the influence of the time factor on the expected development results based on the financial and mathematical apparatus known in the investment theory, reflecting the change in the value of cash flows in different periods of operation. Based on the diversification of regional economies, including economic, technical, social, innovative, investment, scientific and technical and other areas of activity, attention is focused on a comprehensive analysis of all components when calculating the potential. The article formulates the sequence of process stages of assessing the communities’ resource potential. It is proposed to form initial information in the context of three blocks: resource, economic development, growth reserves. This allows you to structure data based on the main aspects of the availability and reproduction of resources, which will provide a rational choice of development strategy. A vision of the assessment system characteristics has been formed, which is obliged to encompass the main constituent elements, which will make it possible to establish the nature of development and the necessary requirements for it. To generalize the assessment, methods are classified that provide the final characteristics, capabilities and scope of their application. The system of indicators for assessing the efficiency of using the economic potential of the region is considered, which includes two main blocks, target and resource.

New method for monitoring the residual life of high pressure hoses

The presented method is designed to monitoring the residual life of hydraulic drive elements. In this work, as an element of the hydraulic drive, high-pressure hoses are used, which are used in hydraulic drives of technological equipment of transport and technological machines. As a diagnostic parameter that characterizes the technical condition of the high-pressure hose, the frequency of natural oscillations of the pipeline with the liquid is adopted. Experimentally, the dependence of the natural oscillation frequency of the high-pressure hose on the dynamic loading cycles of the harmonic type was obtained, which were used to determine the probability of failure of pipelines and to find a strategy for their replacement. The probability of failure of high-pressure hoses for different periods of operation is determined on the basis of the obtained experimental dependences of the natural vibration frequency of pipelines on their operating time. Using the obtained dependences of the probability of failure of high-pressure hoses, it is possible to determine the possible residual life of pipelines and the need for their replacement. This method can be used to determine the probability of failure of other elements of the hydraulic drive, such as hydraulic cylinders, hydraulic valves, pumps, and others.

Emitters and Filters Performance under Treated Sewage Water Reuse with Drip Irrigation

An experiment was carried out under open field conditions on black cotton soil at Agriculture College, Nagpur to study the performance of different types of emitters and filters while using irrigation water of different qualities for different periods of operation. Eight treatments comprising of irrigation water quality as main treatment [domestic treated sewage water (DTSW) from a phytorid sewage treatment plant and deep open well water (WW)], sub-treatments comprising of emitter type (inline and online) and time of operation (60 h and 120 h) of drip system were planned. Gravel filter, followed by disk filter, was used to filter water of different quality. Partial clogging percentage of gravel filter was higher in case of DTSW. Emission uniformity coefficient decreased rapidly in DTSW compared to WW. Mean discharge reduction percentage was 13.23 % in gravel filter, and 18.72 % in disk filter. Emitter’s emission uniformity percentage in WW was better than in DTSW. The manual operation time (i.e. time interval between two consecutive maintenance events) for disk filter was shorter than gravel filter in both treatments. Domestic treated sewage water could be used for crop production with proper maintenance of filter, lateral and emitters.

Emitters and Filters Performance under Treated Sewage Water Reuse with Drip Irrigation

An experiment was carried out under open field conditions on black cotton soil at Agriculture College, Nagpur to study the performance of different types of emitters and filters while using irrigation water of different qualities for different periods of operation. Eight treatments comprising of irrigation water quality as main treatment [domestic treated sewage water (DTSW) from a phytorid sewage treatment plant and deep open well water (WW)], sub-treatments comprising of emitter type (inline and online) and time of operation (60 h and 120 h) of drip system were planned. Gravel filter, followed by disk filter, was used to filter water of different quality. Partial clogging percentage of gravel filter was higher in case of DTSW. Emission uniformity coefficient decreased rapidly in DTSW compared to WW. Mean discharge reduction percentage was 13.23 % in gravel filter, and 18.72 % in disk filter. Emitter’s emission uniformity percentage in WW was better than in DTSW. The manual operation time (i.e. time interval between two consecutive maintenance events) for disk filter was shorter than gravel filter in both treatments. Domestic treated sewage water could be used for crop production with proper maintenance of filter, lateral and emitters.

Comparative analysis of the ecological state of soils near waste landfills of different periods of operation

Comparative analysis of the ecological state of soils near waste landfills of different periods of operation

Reliability forecasting model for power transformers that have fulfilled their standard service life

Today, the urgent tasks of the heat and power industry of the Russian Federation, as many other countries, are the problem of exceeding the service life of high-voltage electrical equipment of transformer and traction substations. This state of affairs leads to adverse consequences in the electric power system, which directly reduces the reliability of power supply to consumers, as well as to increase operating costs and technical losses of electric energy. Under the maximum load of transformers that have fulfilled the standard service life, constant monitoring is required to develop recommendations on the operation and operation modes of power transformers. The article considers the issue of calculating the reliability of power oil transformers. According to the collected statistical information, the most damaged parts of power transformers are identified. The main indicators that characterize the level and condition of the power transformer windings are shown. Using quantifiers of the distribution of the Chi-square, the upper and lower limits of the time between failure of the windings of power transformers for different periods of operation are determined, confidence limits with probability α = 0.9, 0.95, 0.99 are determined. According to the obtained data, the distribution of the Chi-square received a failure flow of the main element - the windings of power transformers with different periods of operation. There is a linear dependence of the decrease in reliability of the power transformers depending on the period of operation.

Viability of turbine blade material with a long service life

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.

Application of the complex parameter of strength and ductility to assess the state of the blades’ material at different periods of operation

The paper is devoted to the study of the material’s condition of guide blades made of heat-resistant nickel alloy with different operating time. It is established that the structure of the blade material and their mechanical properties are not satisfactory for further operation. To recovery the performance properties and structure of the blade material, several types of heat treatment were tested and the optimal one was chosen. The complex parameter of strength and plasticity is calculated and on its basis the estimation of degree of recovery of blade’ material after heat treatment is carried out.

Real-Time Simulation of Force Parameters for Diagnostics of Ceramic Tool Condition During Milling of High-Hardness Steel Parts

Cutting ceramics is a high-performance tool material for high-speed machining of hard steels and alloys. Ceramic materials have high hardness and heat resistance in a wide range of temperatures, as well as chemical passivity in relation to most of the workpieces. However, the wider application of ceramic cutting tools is limited due to the low reliability - unpredictable fragile fracture of the cutting edge in different periods of operation. The study discusses mathematical simulations of force parameters in the milling of hardened steels using ceramic cutting tools. The simulation results were used to develop a system for the metalworking technological system state diagnostics. Mathematical software for calculations of the set of force parameters through computer simulations with taking into account the tool wear has been developed. The developed system allows calculating and graphically displaying a set of force parameters appearing during face milling of hardened steels in the real-time.

Tuning Strategies for Overcoming Fouling Effects in Proportional Integral Derivative Controlled Heat Exchangers

Fouling is one of the main causes of industrial problems regarding operation and control of shell and tube heat exchangers. Although fouling is a time dependent phenomenon, most papers in the literature focus on fouling mitigation in steady-state heat recovery. In this work, a lumped parameter model to describe time-varying conditions and their influence in controller tuning is presented. For each modeling cell, there are four input variables (inlet temperatures and flow rates for shell and tube sides), which generate two output signals (outlet temperatures for shell and tubes). The influence of fouling in process control is evaluated by considering intermediate values of thermal resistance of fouling (Rf), simulating its variation with time. The model was implemented in MATLAB/Simulink, and simulations have been carried out for different periods of operation. A step change was applied in the shell flow rate to evaluate the response in the tube outlet temperature. Results show that periodic fitting in pro...

Time-Dependent Desalination Tests for Small-Scale SWRO Pilot Plant Installed at Urla Bay, Turkey

In this work, performance data from a small-scale reverse osmosis (RO) plant based on seawater FilmTec spiral wound RO membranes for different periods of operation are presented and analyzed. A prototype RO set-up with a 2,200 L/d capacity was installed and operated at Urla Bay which was located in Izmir, Turkey. This study typically investigates RO performance in terms of permeate flux, salt and boron rejections. Thin-flm composite membrane-based RO technology was successfully used with this RO set-up, which gave an average salt rejection of more than 95%. It was found that over a period of 36 hours of continuous operation, the permeate flux decreased by approximately 4% of its initial value but salt rejection stayed nearly constant. In this study, long-term data were also compared with a full-capacity operation using two paralleled membranes and a lowered-capacity operation with a single membrane. The results show that the small-scale RO system was successfully operated to mimic typical large-scale RO plants installed for production of potable water.

Development of Unrecoverable Displacements of the Dam of the Sayano-Shushenskaya Hydroelectric Power Plant While in Use Under Design Load Parameters (1990 – 2016)

Questions regarding the adaption of the dam of the Sayano-Shushenskaya hydroelectric power plant once the designed normal pool level had been reached in 1990 are considered. The impact of natural and technogenic factors on this process at different periods of operation of the structure (prior to repair of the dam and foundation (1990 – 1996), during repair (1996 – 2003), and following repairs (2004 – 2012) are investigated. Causes for amplification of asymmetry in operations between the left-bank and right-bank parts of the dam are established. Data attesting to the existence of a stabilized state of the structure in 2013 – 2016 are presented and conditions that will prevent the development of unrecoverable processes in the near future are formulated.