scholarly journals Method of multiscale coincidence of pulses for measuring temporary loads from moving vehicles in bridges and overpasses

2021 ◽  
pp. 160
Author(s):  
Andrey Levterov
Keyword(s):  
Highway Bridges ◽  
Road Transport ◽  
Technical Condition ◽  
Operating Conditions ◽  
Optical Methods ◽  
Rolling Stock ◽  
Bridge Structure ◽  
Time Intervals ◽  
Number Systems ◽  
Modern Development

Modern development of road transport is characterized by constant updating of the nomenclature of cars (including heavy-duty vehicles), by increasing of intensity and speed of their movement, especially in large metropolises and on roads of national and local significance. This complicates the operating conditions of spans of highway bridges to some extent, leads to their damage and early wear. The deterioration of the technical condition of the structures of the spans is largely due to the increased dynamic impact of the cars on the bridges. The purpose of this article is to measure the amplitude of oscillations of a bridge structure from temporary loads of rolling stock with non-periodic long-term loading by optical methods. In accordance with this goal, it is necessary to develop a technique and device for measuring the amplitude of oscillations of the bridge structure by converting the amplitude of oscillations in time intervals and their subsequent measurement by multi-scale pulse coincidence. In a number of works, digital deployment systems that use number systems with different bases, represented by a family of deployment functions, are considered in detail. Such digital systems in general, are described by the corresponding operating scheme. According to this operating scheme, a method of multiscale matching for measuring time intervals was developed, which formed the basis for measuring the vibration amplitude of the bridge structure. The given mathematical model of calculation of the number of measurement channels was used in the synthesis of velocity transducers and linear displacements based on optical (laser) deployment systems, information conversion devices of radar velocity sensors based on the Doppler effect. Similarly, a frequency comparison device, a digital frequency meter, a digital phase meter, and a number of other frequency-time group devices were synthesized.

scholarly journals MODEL FOR DETERMINATION OF CHARACTERISTICS OF RAILWAY TRAIN REGIME MAPS

2020 ◽  
pp. 132-142
Author(s):  
A. Falendysh ◽  
A. Gatchenko ◽  
O. Kletska ◽  
E. Kiritseva ◽  
M. Barybin
Keyword(s):  
Energy Efficient ◽  
Mechanical Energy ◽  
Technical Condition ◽  
Operating Conditions ◽  
Rolling Stock ◽  
Railway Transport ◽  
Ecological Requirements ◽  
Methods Of Calculation ◽  
Methods Of Operation

The article considers the issues of determining rational approaches to the creation of train maps, the rational use of diesel modes and the use of automated computer simulation system. Based on the obtained results, an energy-efficient mode of train driving is proposed and a mathematical model of the locomotive operation character is created. There is a need to review obsolete regime and train locomotive crews in the latest methods of operation. The basic values and methods of calculation for specific operating conditions on the basis of the law of conservation of mechanical energy are established. It is proposed to create a passport of each locomotive to determine the rational weight norms on the existing service shoulders. After all, overloading or underutilization of the locomotive's resource is associated with loss of profit or the emergence of emergencies. The necessity of the offered methods within the limits of ecological requirements to traction rolling stock is proved. The possibility of forming a rational system of mileage between technical inspections and repairs for each locomotive as a whole on the basis of forecasting and statistics is determined. It is recommended to further implement mathematical modeling and digital means of monitoring the technical condition after repairs to achieve economic efficiency of railway transport.

METHODS FOR ASSESSING THE TECHNICAL CONDITION OF BEARING HUBS IN MEANS OF TRANSPORT

2021 ◽  
Vol 113 ◽  
pp. 191-204
Author(s):  
Zbigniew STANIK ◽  
Andrzej KUBIK ◽  
Damian HADRYŚ ◽  
Csaba CSISZÁR
Keyword(s):  
Road Transport ◽  
Technical Condition ◽  
Operating Conditions ◽  
The Other ◽  
Motor Vehicles ◽  
Testing Device ◽  
Rolling Bearings ◽  
Regular Monitoring ◽  
Wheel Drive ◽  
Vehicle Inspection

This article presents two methods of testing bearing hubs, which may supplement the existing subjective and unreliable methods of diagnostics of rolling bearings used in wheel bearing hubs of motor vehicles and other means of road transport. One of the most important elements responsible for the safety of a vehicle is the bearing hub. Regular monitoring of the technical condition of bearings should become an obligation at vehicle inspection stations when carrying out a technical inspection of a vehicle, authorising it to travel on public roads. This article presents the results of vehicle tests with signs of damage to rolling bearings, using two test stands: one on which the dynamic balancer acted as a device for accelerating the wheel, and the other, which was designed as a test dedicated to automotive rolling bearings, where a dynamic weighbridge was used as the wheel drive, made it impossible to test the wheel at lower rotational speeds. The newly designed and manufactured bearing testing device eliminates the disadvantages of the previous stand, and additionally, enables the measurement of a fully loaded bearing hub, which enables the simulation of real operating conditions on the bearing hub.

IMPROVING THE ACCURACY OF DETERMINING THE FREQUENCY

2021 ◽  
Vol 73 (2) ◽  
pp. 23-31
Author(s):  
L.O. SAVIN ◽  
Keyword(s):  
Internal Combustion Engines ◽  
Internal Combustion ◽  
Road Transport ◽  
Technical Condition ◽  
Operating Conditions ◽  
Combustion Engines ◽  
Optimal Frequency ◽  
Average Operating

The paper substantiates a method for increasing the accuracy of determining the optimal fre-quency of maintenance of one of the most important units of automotive equipment operating in various climatic and road transport conditions - its engines, and also presents circuit proposals for the implementation of this method. The proposed approach makes it possible to significantly increase the accuracy of determining the optimal frequency of maintenance of internal combustion engines by taking into account their real technical condition when operating in different (different from the average) operating conditions. The article provides typical examples of calculating the determination of the optimal frequency of maintenance of automotive equipment, and also estimates the gain achieved when using the approach proposed in the work.

scholarly journals The operation of agricultural tractor with universal ecological oil

2013 ◽  
Vol 59 (Special Issue) ◽  
pp. S27-S33 ◽  
Author(s):  
J. Kosiba ◽  
Z. Tkáč ◽  
Ľ. Hujo ◽  
B. Stančík ◽  
I. Štulajter
Keyword(s):  
Environmental Impact ◽  
Technical Condition ◽  
Operating Conditions ◽  
Hydraulic Pump ◽  
Time Intervals ◽  
Agricultural Tractor ◽  
Lubrication Properties ◽  
Hydraulic Circuits

This contribution presents the results of the research into the characteristics of ecological oil labelled MOL Farm UTTO Synt in the tractor operating conditions. Biodegradable fluid was applied in the gear and hydraulic circuits of the tractor Zetor Forterra 114 41. The fluid was assessed for contamination and lubrication properties by its effect on the wear of tractor hydraulic pump during the application. The hydraulic pump was removed from the tractor at specified time intervals because of its technical condition relating to the flow efficiency. The measurements were calculated as flow efficiency with minimum environmental impact of oil on the hydraulic pump wear.

scholarly journals DETERMINATION OF THE TECHNICAL CONDITION OF A RAILWAY BRIDGE

2020 ◽  
pp. 32-39
Author(s):  
I. Seryh ◽  
E. Chernyshova ◽  
A. Degtyar
Keyword(s):  
Technical Condition ◽  
Operating Conditions ◽  
Industrial Safety ◽  
Normal Operation ◽  
Bridge Structure ◽  
Structural Elements ◽  
Railway Bridge ◽  
Technical Examination ◽  
Second Category

The reliability and durability of any structures, including in transportation, depend on operating conditions and on timely diagnostics of damages and defects arising during their normal operation. Proper diagnostics will allow to determine the degree of wear of the structures, as well as to identify causes of damages. This work will focus on industrial safety inspection, using railway bridge built in 1987 as an example. A comprehensive inspection included full technical examination of the bridge and all its structural elements. The outcome and all necessary repair recommendations are documented. Recommendations for reconstruction and restoration methods of the damaged elements and structures of the bridge are based on a scientifically accurate assessment of its technical condition to establish signs and causes of the damages. Based on the results of the comprehensive inspection of all the damages in the bridge structure, the technical condition of the bridge is assessed three points on a five-point scale. The identified failures in durability and safety are classified in the second category. The categories of defects found are mainly related to safety - B1, B2, durability - D2, D3, and repairability - P2, Р3.

scholarly journals Critical Review of EMC Standards for the Measurement of Radiated Electromagnetic Emissions from Transit Line and Rolling Stock

Energies ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 759
Author(s):  
Andrea Mariscotti
Keyword(s):  
Time Distribution ◽  
Communication Systems ◽  
Electromagnetic Compatibility ◽  
Transportation Systems ◽  
Operating Conditions ◽  
Rolling Stock ◽  
Intrinsic Variability ◽  
Statistical Characterization ◽  
Electromagnetic Emissions

Accurate and comprehensive methods for the assessment of radiated electromagnetic emissions in modern electric transportation systems are a necessity. The characteristics and susceptibility of modern victim signaling and communication radio services, operating within and outside the right-of-way, require an update of the measurement methods integrating or replacing the swept frequency technique with time domain approaches. Applicable standards are the EN 50121 (equivalent to the IEC 62236) and Urban Mass Transport Association (UMTA) with additional specifications from project contracts. This work discusses the standardized methods and settings, and the representative operating conditions, highlighting areas where improvements are possible and opportune (statistical characterization of measurement results, identification and distinction of emissions and line resonances, and narrowband and broadband phenomena). In particular for the Electromagnetic Compatibility (EMC) assessment with new Digital Communication Systems, the characterization of time distribution of spectral properties is discussed, e.g., by means of Amplitude Probability Distribution and including time distribution information. The problem of determination of site and setup uncertainty and repeatability is also discussed, observing on one hand the lack of clear indications in standards and, on the other hand, the non-ideality and intrinsic variability of measurement conditions (e.g., rolling stock operating conditions, synchronization issues, and electric arc intermittence).

scholarly journals Effect of transient processes on the switching stability of dc machines

2018 ◽  
Vol 239 ◽  
pp. 01036 ◽  
Author(s):  
Viktor Kharlamov ◽  
Pavel Shkodun ◽  
Andrey Ognevsky
Keyword(s):  
Magnetic System ◽  
Significant Proportion ◽  
Electrical Energy ◽  
Operating Conditions ◽  
Fine Tuning ◽  
Transient Processes ◽  
Rolling Stock ◽  
Electric Motors ◽  
Electric Rolling Stock ◽  
Switching Stability

Effective use of fuel and energy resources is one of the main tasks in modern industry and transport. The main directions of increasing the energy efficiency of the electric rolling stock of railways are considered in the paper. For the electric rolling stock of railways, a significant proportion of electric power consumption falls on traction needs. The consumption of electrical energy and its recovery directly depends on the proper operation and fine-tuning of the magnetic system and switching of traction electric motors of the rolling stock. The methods of testing traction electric motors currently used in railway transport do not fully correspond to their operating modes during operation. For more reliable control of their condition, a methodology for estimating the nature of the operation of traction electric motors in conditions close to real ones was proposed. Studies of the influence of transient processes on the quality of switching of traction electric motors taking into account operating conditions are carried out. Based on the results of the study, the analysis of the data obtained is carried out, and a criterion for estimating the switching stability of traction electric motors in transient operation modes is proposed. The proposed criterion allows carrying out quality control of the tuning of the magnetic system and switching of the traction electric motor, and also estimating the nature of its operation in various modes, taking into account the operating conditions.

Significant innovations of the foreign automobile in-dustry. Construction and technological measures

2021 ◽  
pp. 272-278
Author(s):  
V.А. Grushnikov
Keyword(s):  
Research Design ◽  
Road Transport ◽  
Conveyor Belt ◽  
Rolling Stock ◽  
Development Trends ◽  
Innovative Solutions ◽  
Wheeled Vehicles ◽  
Current Standards

Increasing the competitiveness and improving the consumer properties of the rolling stock of road transport is achieved by the development and implementation into practice of components and innovative solutions assembled on a conveyor belt of automobile wheeled vehicles that are ahead of the requirements of current standards. These innovations define development trends. Keywords: automobile rolling stock; structures; technologies; units; research; design; manufacture; operation

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.

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