scholarly journals Criteria Justification for Assessing the Technical Condition of Gearboxes of Mining Machines Based on Infrared Thermography

2020 ◽  
Vol 174 ◽  
pp. 03003 ◽  
Author(s):  
Evgeniy Kuzin ◽  
Boris Gerike ◽  
Vitaliy Shachmanov
Keyword(s):  
Heat Release ◽  
Theoretical Basis ◽  
Technical Condition ◽  
Operating Conditions ◽  
The Body ◽  
Mining Machine ◽  
Belt Conveyor ◽  
Actual Load ◽  
Early Failures ◽  
Complex Technical Systems

The paper presents the relevance of advanced assessment of the technical condition of complex technical systems. One of which is the gearbox of a mining machine. The main reasons for early failures of bearings are shown. The main share is occupied by problems of lubrication, incorrect installation and maintenance. The analysis of types of destruction of gears of mining machines is presented. The main share is occupied by the surface coloring of the teeth and sudden fracture of the tooth as a result of dynamic load. The theoretical basis for determining the heat release of bearings is given. The calculation of heat release is given of a shaft belt conveyor gearbox as an example, which is confirmed by thermographic studies under operating conditions. Justification of criteria for evaluating the technical condition of gearboxes of mining machines in the form of temperature anomalies recorded on the surface of the body, The actual load on the output shaft is taken into account.

scholarly journals Promising model range career excavators operating time assessment in real operating conditions

2020 ◽  
Vol 242 ◽  
pp. 228 ◽  
Author(s):  
Sergey IVANOV ◽  
Polina IVANOVA ◽  
Sergey KUVSHINKIN
Keyword(s):  
Good Condition ◽  
Operating Time ◽  
Mining Industry ◽  
Negative Influence ◽  
Technical Condition ◽  
Operating Conditions ◽  
Economic Losses ◽  
Mining Machine ◽  
Mining Equipment ◽  
Detailed Assessment

The development prospects of the mining industry are closely related to the state and development of modern mining machinery and equipment that meet the technical and quality requirements of mining enterprises. Enterprises are focused on a quantitative assessment – the volume of mineral extraction, depending on the functioning efficiency of a promising series of mining machines, which include modern mining excavators. Downtime and unplanned shutdowns of mining excavators directly depend on the operating conditions of the mining machine, which has negative influence on the machine as a whole and its technical condition, which entails a decrease in the efficiency of using expensive mining equipment and economic losses of the mining enterprise. The rationale for external factors that affect the operating time and technical condition of mining excavators is given. For a more detailed assessment of the influence of external influences on the efficiency of operation of mining machines, the influencing factors are divided into two groups: ergatic, directly related to human participation, and factors of a natural-technogenic nature, where human participation is minimized. It was revealed that factors of a natural-technogenic nature have the greatest influence. An algorithm is proposed for a comprehensive assessment of the technical condition and forecasting of operating time both in nominal and in real operating conditions, taking into account factors of a natural and technogenic nature. It is proposed, based on the developed program for planning and evaluating the life of a mining excavator, to adjust the schedules for maintenance and repair (MOT and R) in order to minimize the number of unplanned downtime of a mining excavator and maintain it in good condition.

scholarly journals Geotechnology of restoration of culverts in complex ground conditions without their decommissioning

2019 ◽  
Vol 265 ◽  
pp. 05003
Author(s):  
Nicolay Perminov ◽  
Andrey Perminov
Keyword(s):  
Experimental Design ◽  
Technical Condition ◽  
Operating Conditions ◽  
The Body ◽  
Construction Site ◽  
Engineering Structures ◽  
Design Work ◽  
Concrete Pipes ◽  
Ground Conditions ◽  
Water Disposal

In the article, on the basis of extensive theoretical and experimental research carried out, innovative geotechnology for repair of culverts is presented, which provides an improvement in the conditions for interaction between the body of the structure and the soil massif with increasing technogenic impacts. The analysis of the technical condition of the culvert transport and engineering structures under special operating conditions is given. Factors determining their premature emergency condition and interfering with stable functioning under increasing loads and impacts have been studied. On the basis of many years of experimental and theoretical and experimental design work, geotechnology «Saturn» has been proposed, suitable for repairing all types of culverts on railroads and highways, engineering infrastructure facilities, and especially for repair and reconstruction of pipes under conditions of a constant intensive watercourse with nonstandard (atypical) constructive solutions, as well as located in hard-to-reach and difficult for the organization of the construction site sections of the route. The experience of successful application of the developed technology "Saturn" on the railroad during the repair and reconstruction of long-maintained culverts of stone and concrete pipes under the conditions of a constant intensive watercourse and at water disposal facilities during repair of deep tunnels without their decommissioning is described.

Investigation of the interaction of car wheels with the stand rollers during braking

2021 ◽  
Vol 13 (1) ◽  
pp. 68-77
Author(s):  
Igor Мarmut ◽  
◽  
Andriy Kashkanov ◽  
Vitaliy Kashkanov ◽  
◽  
...  
Keyword(s):  
Traffic Safety ◽  
Technical Condition ◽  
The Body ◽  
Power Model ◽  
Equilibrium Equations ◽  
Design Features ◽  
Complex Objects ◽  
Passenger Cars ◽  
Wheel Drive ◽  
Four Wheel Drive

The article discusses the issues of modeling conditions for obtaining diagnostic information about complex objects. As an example, the study of the braking qualities of four-wheel drive cars on an inertial roller stand is considered. Diagnosing the technical condition of cars from the point of view of traffic safety is one of the most important problems. This is especially important for systems whose technical condition affects traffic safety: especially braking systems. Foreign and domestic experience testifies to the effectiveness of instrumental control. The diagnostic equipment includes roller stands, on which you can check the braking properties of cars. As shown by many studies, in particular, carried out at the Department of Technical Operation and Service of Automobiles, KhNADU (HADI), inertial stands provide more reliable information about the technical condition of the car. Such stands allow you to reproduce the real speed and thermal modes of the brakes (especially those equipped with ABS). To improve the accuracy of diagnosing a car on a roller stand, it is necessary to have an idea of the nature of the interaction of the car wheels with the rollers. The studies of wheel rolling on the stand rollers have been carried out by many authors since the 80s of the last century. However, all these studies were carried out on uniaxial stands and for mono-drive vehicles. Nowadays, a large number of passenger cars have four-wheel drive. Rolling of the wheels of such cars on rollers and their interaction has practically not been studied. Therefore, a return to the study of this issue is relevant. A power model of the system of interaction between the car and the stand has been developed, taking into account the design features of the stand and the design features of the car's suspension. The power model of the system under consideration contains the equilibrium equations of the body and two bridges and the equations of motion of the rollers and wheels of the car. Based on the results of the analysis of the acting forces in the "car-stand" system, the braking moments on the wheels M and the coefficients of the use of the load q during the braking tests of a 4x4 vehicle were determined. The obtained research results allowed to improve the theory of interaction of a car wheel with the rollers of an inertial diagnostic stand.

Probabilistic Analysis of Intermediate Floor Steel and Wooden Structures in the Old Urban Development Building

2014 ◽  
Vol 633-634 ◽  
pp. 1140-1147
Author(s):  
Vladimir Alekseevich Sokolov
Keyword(s):  
Information Theory ◽  
Urban Development ◽  
Probabilistic Analysis ◽  
Technical Condition ◽  
Probabilistic Methods ◽  
Technical Diagnostics ◽  
Structural Elements ◽  
Complex Technical Systems ◽  
Technical Systems ◽  
Wooden Structures

The article suggests an approach to determine structural elements technical condition, based on the mathematical probabilistic apparatus of technical diagnostics. Diagnostics are performed using probabilistic methods of complex technical systems conditions recognition. Probabilistic parameters are calculated according to Bayes’s rule. The paper shows a diagnostics example of intermediate floor elements and systems in the old urban development building. Both the suggested method and information theory methods are used during diagnostics.

Combustion Improvement System in Boilers and Incinerators

2003 ◽  
Author(s):  
Wlodzimierz Blasiak ◽  
Weihong Yang
Keyword(s):  
Temperature Distribution ◽  
Heat Release ◽  
Combustion Chamber ◽  
Flue Gas ◽  
Operating Conditions ◽  
Waste Incinerator ◽  
The Novel ◽  
Biomass Waste ◽  
Injection Angle ◽  
Waste Incinerators

This work presents the main features, advantages and evaluation of applications of the novel “Ecotube” combustion improvement and emission reduction system by Ecomb AB of Sweden and Synterprise, LLC of Chattanooga, Tennessee. In the Ecotube system, the nozzles used for mixing are put on the suitable position inside the combustion chamber to control uniformity of temperature, mixing and reactants distribution in boilers and incinerators since the formation and reduction of pollutants (NO, CO and VOC) and in-furnace reduction processes (Air/Fuel staging, SNCR, flue gas recirculation and SOx reduction by dry sorbent injection) are related directly to mixing in a combustion chamber. The novel Ecotube combustion improvement system allows better control of mixing of the gases for example from a primary combustion zone with secondary combustion air or a recirculated flue gas. By means of the novel system it is possible to better control the residence time and to some degree gas phase temperature distribution as well as the heat release distribution in the furnace of the waste incinerators or boilers. This new combustion improvement system can be applied to supply different gas or liquid media — for example air, fuel, urea or even solid powder. Using the system a more efficient and environmentally clean combustion or incineration process can be performed. The Ecotube System may be used to meet increasingly stringent environmental emissions regulations, such as NOx SIP Call, while it delivers added benefits of reduced and stabilized CO and reduced fly ash and improved boiler efficiency. The study tool used in this work to present influence of the Ecotube system design on temperature as well as uniformity of reactants and flow field is numerical modeling. Using this tool, the influence of the position of the Ecotube system and the injection angle of the nozzles are studied. The studied boilers included the biomass waste incinerator, municipal solid waste incinerator and coal fired boiler. The concept of the Heat Release Distribution Ratio is proposed to classify the heat release inside the upper furnace of the boilers or incinerators. The results show that Ecotube spreads reaction zone over a larger furnace volume. The furnace flame occupation coefficient can be as high as 45% with the Ecotube system and it is around 40% higher comparing with the conventional multinozzle mixing system. Ecotube system allows keeping far more uniform heat release distribution, more uniform temperature distribution, and thus longer life of the heat transfer surfaces inside the furnace. Position of the Ecotube system and the injection angle of the nozzles are of primary importance and can be used as a technical parameter to control the boiler operation at different loads and varying operating conditions.

scholarly journals Методика для трибодиагностики судовых крейцкопфных дизелей на основе имитационного моделирования

2020 ◽  
Author(s):  
A.V. Golenishev ◽  
A.V. Nadezkin ◽  
M.E. Starchenko
Keyword(s):  
Diesel Engine ◽  
Simulation Model ◽  
Technical Condition ◽  
Operating Conditions ◽  
Marine Diesel Engine ◽  
Threshold Values ◽  
Piston Group ◽  
Marine Diesel ◽  
Cylinder Piston ◽  
Wear Products

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.

scholarly journals The influence of centrial forces on crankshaft bearing lubrication is in emergency modes of the engine of the car

2021 ◽  
Vol 12 (2) ◽  
pp. 112-121
Author(s):  
Oleksandr Khrulev ◽  
◽  
Olexii Saraiev ◽  
Iryna Saraieva ◽  
◽  
...  
Keyword(s):  
Internal Combustion Engines ◽  
Operating Mode ◽  
Internal Combustion ◽  
Technical Condition ◽  
Operating Conditions ◽  
Combustion Engines ◽  
Connecting Rod ◽  
Oil Supply ◽  
Technical Expert ◽  
The Difference

The analysis of the crankshaft bearing condition of the automotive internal combustion engines in the case of insufficiency and breakage of oil supply to them is carried out. It is noted that this fault is one of the most common causes of damage to rubbing pairs in operation. At the same time, the different groups of bearings are often damaged, which cannot be explained within the framework of existing models of plain bearing lubrication. The objective of the work is to develop a mathematical model of oil supply to connecting rod bearings in emergency mode, taking into account the characteristic features of the bearing design. The model also, depending on the nature of the damage, should help to determine and explain the causes of bearing failures if they occur in different modes when operating conditions are broken. A computational model has been developed that makes it possible to assess the effect of design differences in the features of oil supply and the action of the centrifugal forces during crankshaft rotation on the oil column in the lubrication hole where oil is supplied to the conrod bearing. Calculations of the change in time of the oil supply pressure to the connecting rod bearings for the various designs of the crankshaft lubrication holes have been performed. It is shown that, depending on the operating mode of the engine and its design, the oil pressure in front of the connecting rod bearings does not disappear immediately after oil supply failure to crankshaft. Moreover, the lower the crankshaft speed is, the longer the lubrication of the conrod bearings will continue. The calculation results are confirmed by the data of the expert studies of the engine technical condition, in which the crankshaft was wedged in the damaged main bearings was found in the absence of serious damage to the connecting rod ones. It has been found that such features of the damage correspond to an rapid breakage of the oil supply to the crankshaft in the case of such operational damage as the oil pump and pressure reducing valve failure, the oil filter seal and oil pan destruction, etc. The developed model explains the difference in lubrication conditions and in the damage feature to the main and connecting rod bearings in the emergency cases of the oil supply breakage, which are observed during operation, and helps to clarify the failure causes. This makes it possible to use the model and the obtained data when providing auto technical expert studies of the failure causes of automobile internal combustion engines This makes it possible to use the model and the obtained data when providing auto technical expert studies of the failure causes of automobile internal combustion engines when the operating conditions are broken.

scholarly journals TECHNICAL CONDITION OF CORRUGATED METAL TRANSPORT STRUCTURES

2021 ◽  
pp. 38-50
Author(s):  
J. J. LUCHKO ◽  
V. V. KOVALCHUK
Keyword(s):  
Bearing Capacity ◽  
Technical Condition ◽  
The Body ◽  
Soil Environment ◽  
Metal Structures ◽  
Advantages And Disadvantages ◽  
Methods Of Calculation ◽  
Analysis And Synthesis ◽  
The Impact ◽  
Corrugated Metal

Purpose. The purpose of the work is to establish the real technical condition of transport structures made of corrugated metal structures on the basis of the analysis of scientific and technical sources.And to analyze the experience of operation of metal corrugated structures in the soil environment and to form and generalize the problems of ensuring the reliability and durability of structures made of metal corrugated structures in the conditions of operation on railways and highways of Ukraine. Methodology. To achieve this goal, a review of scientific and technical sources and regulations of different countries on the technical condition of transport facilities in Ukraine was conducted. In particular, data on the distribution of bridges and pipes made of corrugated metal structures by mode of transport are given. It is shown that the development and implementation of new technologies for the repair of existing defective pipes and small bridges, both on the railways and highways of Ukraine is a very important issue. A thorough analysis of the experience of operation of corrugated metal structures in the soil environment in different countries was conducted. Data on the main inadmissible defects of pipes and the reasons of their development are given. CMS' (corrugated metal structures) corrosion and other defects are given. A number of examples of overpass defects, collapse of bridges and structures with MCS in operation are presented. The qualitative indicators of metal corrugated structures, their advantages and disadvantages are also considered, the problems and the analysis of ensuring the reliability and durability of the structures with CMS in the conditions of operation on the railways and highways of Ukraine are formulated. Findings. An analysis of domestic and foreign scientific and technical sources on the technical condition of transport facilities in Ukraine was conducted. In particular, the experience of operation of corrugated metal structures in different countries of the world is studied and generalized. The analysis and synthesis of problems of ensuring the reliability and durability of buildings with CMS in the conditions of operation on the railways and highways of Ukraine. Originality. As a result of the analysis of the technical condition of transport facilities operated on railways and highways of Ukraine, it was found that about 15 % of transport facilities – small and medium bridges and culverts on Ukrainian railways and about 45 % of transport facilities on Ukrainian roads have unacceptable defects and require immediate repair and replacement. Also, it was established on the basis of research that there are no methods for assessing the load-bearing capacity of transport facilities with CMS in the presence in the body of the embankment of the railway or highway metal corrugated structures with a diameter greater than 6 m. It was determined that standards don't include regulations on design and monitoring of CMS on railway tracks. Practical value. On the basis of these data it was possible to offer directions of theoretical and experimental research and methods of calculation, tests of CMS and diagnostics of a technical condition of transport structures with CMS. In particular, the measurement of the impact of the environment on the bearing capacity of the CMS and the measurement of residual deformations of the corrugated metal pipe on the railway track. Execution of the analysis and synthesis of methods of calculation of transport constructions with CMS will lead to improvement of methods of calculation of CMS.

scholarly journals Algorithms and models of power losses in circuit breakers installed in networks

Vestnik MGTU ◽  
2020 ◽  
Vol 23 (4) ◽  
pp. 345-353
Author(s):  
E. I. Gracheva ◽  
A. N. Gorlov ◽  
A. N. Alimova
Keyword(s):  
Power Supply ◽  
Low Voltage ◽  
Technical Condition ◽  
Active Power ◽  
Operating Conditions ◽  
Public Utility ◽  
Electrical Networks ◽  
Power Losses ◽  
Circuit Breakers ◽  
Technical Parameters

Determination of the main characteristics of the topology and technical condition of equipment underoperating conditions is necessary for analyzing and assessing power and electricity losses in intrashoplow-voltage industrial power supply networks. A comparative analysis of the technical characteristicsof automatic circuit breakers VA57-31 (KEAZ), NSX100 TM-D (Schneider Electric), DPX3 160 (Legrand), Tmax XT1 TMD (ABB) has shown that the main technical parameters of the machines are close in their values. At that it has been found out that automatic switches of the BA57-31 series have the lowest value of power losses per pole (7.5 W), whereas the automatic switches of the Tmax XT1 TMD series have the highest value (10 W). Thus, under the operating conditions of the equipment, the lowest value of power and electricity losses is characteristic of low-voltage electrical networks with installed circuit breakers of the BA57-31 series, and the highest value of losses is noted in in-shop systems with installed circuit breakers Tmax XT1 TMD. Using catalog data, the dependences of active power losses in circuit breakers on rated currents have been established; the algorithms have been developed and the obtained dependences have been modeled using approximating functions. The standard deviation of the compiled approximating functions has been calculated. Analytical expressions of the dynamics of power losses per pole have been determined as a function of the rated current. The graphical dependences of the investigated parameters of low-voltage equipment have been presented. The developed models are recommended to be used to increase the reliability of the assessment and refinement of the amount of active power and electricity losses in low-voltage electrical networks of industrial power supply systems, agrotechnical complexes, and enterprises of the public utility sector.

scholarly journals Assessment of the technical condition of lift guides using a magnetic field

2021 ◽  
Vol 2130 (1) ◽  
pp. 012003
Author(s):  
P Lonkwic ◽  
T Krakowski ◽  
H Ruta
Keyword(s):  
Early Stage ◽  
Technical Condition ◽  
Operating Conditions ◽  
Measuring Head ◽  
Cross Sectional ◽  
Correct Operation ◽  
Emergency Braking ◽  
Wear And Tear ◽  
Equipment Failures ◽  
Novel Concept

Abstract The systems that monitor individual components of machines and devices are under constant development. The ability to detect damages at an early stage allows failures to be prevented, so any uncontrolled downtime can be predicted in a controlled manner. Continuous monitoring of technical condition is an activity that also helps to reduce the losses due to equipment failures. However, not all areas can be monitored continuously. Such areas include lift guides where wear and tear can occur naturally, i.e. through abrasion of the material layer due to interaction with moving guide shoes or after emergency braking. Emergency braking causes local damages to the guide through plastic deformation of its surface resulting from indentation of the knurled roller of the brake. Such places are cleaned mechanically, which results in local reduction of the cross-sectional area. In such a case, it is difficult to continuously assess the technical condition of guides due to the prevailing operating conditions. Therefore, a concept of a head enabling assessment of the technical condition of guides at every stage of their operation has been developed. This article presents the novel concept of a magnetic head used for assessing the technical condition of lift guide rails that are the running track of lifting equipment. The initial tests were performed on the original test setup. The concept of the developed measuring head was verified for correct operation on specially prepared flat bars with holes. The results obtained in the form of laboratory tests proved that the proposed measuring head concept can be applied to the measurements under real conditions.

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