scholarly journals STUDY OF TRANSPORTATION PROCESS AS A FACTOR OF RAILWAY TRACK OPERATION

2020 ◽  
pp. 60-65
Author(s):  
М. А. АРБУЗОВ ◽  
Є. В. АРБУЗОВА
Keyword(s):  
Lateral Force ◽  
Railway Track ◽  
Rolling Stock ◽  
Operational Parameters ◽  
Rail Head ◽  
Rolling Surface ◽  
Transportation Process ◽  
Longitudinal Slope ◽  
Technical Systems ◽  
Regional Branch

Abstract. The transportation process depends on the state of the technical systems involved. Technical systems depend on the organization of the transportation process. The paper considers the influence of operational parameters on the condition of the railway track. To study this problem, the most difficult section of the Slavsko-Lavochne-Beskid-Volovets track was chosen at the Lviv Railway regional branch. The influence of the missed tonnage, radius of the curve, longitudinal slope, speed and increase of the outer rail on the lateral wear of the rail head was investigated. It is established that all factors are influential. But the most influential - the longitudinal slope, in second place - speed, in third place - the radius of the curve. The effect of the slope on the rise was greater than the effect of the slope on the descent 3.3 times. A multiparametric mathematical law is established, which reflects the process of lateral wear of the rail head depending on the operational factors. This function allows you to predict the amount of lateral wear of the rail. Significant deviation of actual wear from the calculated, called excessive wear. From the analysis of data of the regional branch "Lviv Railway" it follows that 40% of the curved sections of the track with excessive wear are located on the section Slavsko-Lavochne-Beskid-Volovets. During the Lavochne-Beskid 1629 km pk9 race on the odd track, the test section of the track was equipped with strain gauges and prognometers, which were installed in the places of the smallest and largest lateral wear. There was an increase of 34% in lateral force in the cars in front of the pusher locomotive. No exceedance was detected. Observations at the Lavochne-Beskid race showed that the rolling stock was moving at a speed of 35 km/h. Thus, the established speed of movement of freight trains makes 60 km / h and during calculations is accepted as the minimum freight. That is, there is an under-realization of speed. Calculations show that this reduces the service life of the rails by 38%. Metal ingots in the shape of a wheel crest and a rolling surface were also found in the track. These ingots, formed from scales and drops of metal, are formed as a result of excessive braking in the pass sections, which is a consequence of the heavy weight of the train and steep descents. The paper develops recommendations for the transportation process in areas of complex plan and profile.

scholarly journals INVESTIGATION THE INFLUENCE DIFFERENCE OF THE WAGON’S WHEELS DIAMETERS ON ITS DERAILMENT BY QUASI-DYNAMICS METHOD

2019 ◽  
pp. 608-614
Author(s):  
A. Kuzyshyn
Keyword(s):  
Lateral Force ◽  
The Body ◽  
Rolling Stock ◽  
Wheel Pair ◽  
Rail Head ◽  
Rolling Surface ◽  
Significant Difference ◽  
Negative Effect ◽  
The Difference ◽  
Dynamics Method

In the article the author notes that the horizontal forces arising in the process of pressing the wheel flanges to the working edge of the rail, under certain conditions can be very significant. These forces, in combination with the wheel unloading, caused by the geometric deviation of the track in the plan and profile, can lead to rolling the wheel of the wheelset onto the rail head and, as a consequence, to the stock derailment. Such pressing of the wheel to the rail head in the straight part of the track can occur when faults in the running gears of the wagons: non-parallelism of the axles of the wheel pairs of the bogie frame by the difference in the bases of the side frames, wear of the guide axle-box openings; the difference of the flanges on one wheel pair is more than permissible, wear of the body and bogie bolster center plates, step bearing; a significant difference in the diameters of the wheels of the wheelset caused by the intense wear of the rolling surface of one of them, etc. The article deals with the investigation of the influence of the wheels’ diameters difference of the wheelset on the amount of lateral force for the empty and loaded state of the rolling stock wagon. The results obtained made it possible to conclude that an increase in the wheels’ diameters difference of the wheelset of a loaded wagon of rolling stock leads to more intensive growth of the lateral force, as compared with the exhaust. This is caused by the linear dependence of the lateral force on the mass of the wagon of the rolling stock. However, for both the empty and the loaded wagon, the increase in the lateral force value has a negative effect. In conjunction with the unloading of the wheel it increases the probability of rolling in the wheel of the wheelset on the rail head. Also, an increase in the action of the lateral force from the wheelset on the rail, causes increased wear of the rail, the wheel flange, which is pressed. At the same time, rolling surfaces of an irregular shape are formed on the surface of the other wheel. Therefore, it is important to ensure the maintenance of the wheels of a wheel pair with the smallest difference in its diameters. Key words: rolling stock, diameter difference of wheels, quasi-dynamics method.

scholarly journals Research of safety indicators of diesel train movement with two-stage spring suspension

2018 ◽  
Vol 234 ◽  
pp. 05003 ◽  
Author(s):  
Andriy Kuzyshyn ◽  
Andriy Batig ◽  
Sergei Kostritsa ◽  
Julia Sobolevska ◽  
Vitalii Kovalchuk ◽  
...  
Keyword(s):  
Traffic Safety ◽  
Motor Vehicle ◽  
Stability Margin ◽  
Accurate Method ◽  
Railway Track ◽  
Rolling Stock ◽  
Operational Parameters ◽  
Wheel Pair ◽  
Rail Track ◽  
Safety Parameters

The problem of the interaction of rolling stock with the rail track has been analyzed in the present paper. It has been established that in the process of transport science development a number of methods for determining the causes of wheel pairs derailment are developed, which, in a varying degree, take into account the peculiarities of their interaction. The problem of choosing the most accurate method for estimating the causes of rolling stock derailment becomes more complicated because of the lack of sufficient experimental data that would allow us to verify the adequacy of the models. The indicators of stability of the wheel against derailment, which are used on the railways of Ukraine and Europe, have been examined. Their dependences on the speed of movement were derived. It has been established that the increase of the speed of motion leads to the increase of the interaction power of the rolling stock with the rail track, which may, under certain operational parameters, provoke its derailment. As a result of the calculations, it has been shown that the use of norms for car design and calculation used on Ukrainian railways can lead to an inadequate estimation of traffic safety parameters, since it does not take into account the unevenness of the railway track. It has been established that the requirements of BS EN 14363: 2005 European norms are stricter in comparison with the norms for calculation and evaluation of the bearing elements strength and dynamic qualities of motor-vehicle rolling stock used on Ukrainian railways. A comparison of the experimentally and theoretically calculated values of the stability margin coefficient against wheel derailment of the first wheel pair of the diesel train car was carried out.

Analysis of failures in the operation of technical means on the example of the landfill of the Northern Railway

2020 ◽  
Vol 1 (4) ◽  
pp. 345-351
Author(s):  
O. V. Bykova
Keyword(s):  
Power Supply ◽  
Railway Track ◽  
Rolling Stock ◽  
Technical Equipment ◽  
Railway Transport ◽  
Available Bandwidth ◽  
Regulatory Documents ◽  
Transportation Process ◽  
Analysis Of Failures

Discussed issues that affect the reliability of various elements of the infrastructure of railway transport, such as the railway track, power supply devices, artificial structures, rolling stock, automation devices, telemechanics and communications. The main technical devices of railway transport are listed. The classification of failures in the operation of technical means of transport is given, depending on their category; classification of technical equipment, the failures of which are subject to obligatory accounting or to be accounted for in cases of their influence on the transportation process in accordance with regulatory documents in force in railways. As a result of working with the initial data on failures that caused train delays, the main services involved in the occurrence of failures in the operation of technical equipment at the Northern Railway training ground were identified; also provides an analysis of failures in the operation of technical equipment in the regions of the Northern Railway. Classifier of the causes of failures in the operation of technical facilities by services and the causes of the occurrence on the Northern Railway, which most failures fall on, is formed; identified the main reasons for the failure of the relevant units of the railway transport. The dependence of the available bandwidth on the reliability coefficient is given.

scholarly journals Assessing the influence of wheel defects of a rolling stockon railway tracks

Vestnik MGSU ◽  
2015 ◽  
pp. 61-72 ◽  
Author(s):  
Yuriy Nikolaevich Mazov ◽  
Aleksey Alekseevich Loktev ◽  
Vyacheslav Petrovich Sychev
Keyword(s):  
Plastic Deformation ◽  
Contact Zone ◽  
Rail Steel ◽  
Contact Stresses ◽  
Railway Track ◽  
Rolling Stock ◽  
Elastic Model ◽  
Wheel Load ◽  
Friction Forces ◽  
Rail Head

Transfer of the load from the wheels on the rail occurs at a very small area compared with the size of the wheels and rails. The materials near this site have a very large voltage. Determination of contact stresses is complicated by the fact that the magnitude of these stresses in the rails under actually revolving wheel load exceeds the yield and compressive strength of modern rail steel. We should note that the metal of the rail head, experiencing contact stresses, especially when the location of the pads is closer to the middle of the rail head, works in the conditions close to the compression conditions, and therefore can withstand higher voltage without plastic deformation than the standard compressible sample. But, as a rule, the observed hardening of the metal in the zone of contact stresses and lapping at the edges of the rail head indicates the presence of plastic deformation and, consequently, higher stresses in the wheel-rail contact zone than the yield strength of the metal rail even in the conditions of its operation in the rail head.The use of the design equations derived on the basis of the Hertz theory for metal behavior in elastic stage, is valid. The reason is that each individual dynamic application of wheel loads on the rail is very short, and the residual plastic deformation from the individual loads of the pair of wheels on the rail is actually small. This elastic-plastic deformation of the rail becomes visible as a result of gradual gaining of a missed tonnage of rails and wheels respectively. Irregularities on the running surface of the wheels are of two types. The most common are the so-called continuous bumps on the wheel, when due to the uneven wear of rail the original shape of the wheel across the tread surface distorts. But nowadays, more and more often there occur isolated smooth irregularities of the wheel pairs, due to the increased wear of the wheel because of the stopping and blocking of wheels of the vehicles - slides (potholes), etc.The motion of the wheels with irregularities on the surface of the rail leads to vertical oscillation of the wheel, resulting in the forces of inertia, which is an additional load on the rail. In case of movement of the wheel with isolated roughness on the tread surface of the slide there is a strike, having a very large additional impact on the rail. Such attacks can cause kinked rails, especially in the winter months when there is increased fragility of rail steel, because of lowered temperatures. This is an abnormal phenomenon and occurs relatively rarely, at a small number of isolated irregularities on a wheel of the rolling stock. As correlations connecting the contact force and local deformation in the interaction of the wheel-rail system, we use the quasi-static Hertz’s model, linear-elastic model and two elastoplastic contact models: Alexandrov-Kadomtsev and Kil’chevsky. According to the results of Loktev’s studies ratios of the contact Hertz’s theory are quite suitable for modeling the dynamic effects of wheel and rail for speeds up to 90 km/h for engineering calculations. Since the contact surface is homogeneous and isotropic, the friction forces in the contact zone are not taken into account, the size of the pad is small compared to the dimensions of the contacting bodies and characteristic radii of curvature of the undeformed surfaces, the contacting surfaces are smooth.When train is driving, the position of the wheelset in relation to the rails varies con- siderably, giving rise to different combinations of the contact areas of the wheel and rail. Even assuming constant axial load the normal voltage will vary considerably because of the differences in the radii of curvature of the contacting surfaces of these zones. Thus, the proposed method allows evaluating the influence of several types of wheel defects on the condition of the rail and the prospects of its use in the upper structure of a railway track on plots with different speed and traffic volumes. Also the results can be used to solve the inverse of the considered problems, for example, when designing high-speed highways, when setting the vehicle speed and axle load, and the solution results are the parameters of the defects, both wheelsets and the rails, in case of which higher require- ments for the safe operation of railways are observed.

Development of a device for application of vertical and lateral forces on rail head for determination of scale of strain measurement circuits for measuring influence of rolling stock on track

2020 ◽  
pp. 50-55
Author(s):  
Darya Vladimirovna Rasshhepkina ◽  
◽  
Mariya Viktorovna Zimakova ◽  
Dmitriy Vladimirovich Beloborodov ◽  
◽  
...  
Keyword(s):  
Strain Measurement ◽  
Structural Strength ◽  
Lateral Force ◽  
Rolling Stock ◽  
Vertical Force ◽  
New Device ◽  
Rail Head ◽  
Lateral Forces ◽  
Axis Of Symmetry

On the basis of analytical method of studying devices for the application of forces on a rail head and numerical method of calculating structural strength the authors have developed a new device for loading the rail head by vertical and lateral forces. The device that simulates force of wheel influence on rail allows applying vertical force on the axis of symmetry and with the offset of ±20 mm simultaneously with lateral force. Due to the lightened collapsible frame and the existence of roller bearings the device is comfortable in use, which contributes to the increase of speed of tests on the influence on track and researches in this sphere.

Develop a New Approach Measuring the Wheel/Rail Interaction Loads

2021 ◽  
Author(s):  
Yuriy Boronenko ◽  
Rustam Rahimov ◽  
Waail Mahmod Lafta
Keyword(s):  
Heavy Traffic ◽  
Lateral Force ◽  
Railway Track ◽  
Rolling Stock ◽  
Strain Gauges ◽  
Lateral Impact ◽  
Railway Engineering ◽  
The Right ◽  
And Control ◽  
The Impact

Abstract Determine and control the impact of rolling stock on the railway track, one of the significant subjects of railway engineering, especially with heavy traffic and innovative freight cars with increased axle loads. Different methods utilized to measure the lateral impact of rolling stock on a railway based on the use of strain gauges installed on the rail differ in the location of strain gauges and the specifics of processing the received signals. The shortage of these methods that the lateral force arising from the wheel/rail interaction determined when the wheel position over the strain gauges sections. Therefore, continuous registration of details in the wheel/rail contact is impossible. Multiple passes of the test rolling stock along the measuring section are required to receive the right results. In this article, a new method developed to continue recording the lateral forces of the wheel/rail interaction by measuring stresses in two sections of the rail on a significant part of the sleeper space. The railway track experiments approved this method’s ability to restore the lateral force of not more than 4% standard deviation along the measuring zone’s length and increased the volume of reliable statistical data obtained, improved the measurement accuracy, and reduced the time and cost.

Tribology of rail bogie

2018 ◽  
Vol 77 (4) ◽  
pp. 230-240
Author(s):  
D. P. Markov
Keyword(s):  
Contact Fatigue ◽  
Basic Element ◽  
Difficult Problem ◽  
Railway Track ◽  
Rolling Stock ◽  
Kinematic Parameters ◽  
Approximate Estimation ◽  
Railway Bogie ◽  
Classical Calculation

Railway bogie is the basic element that determines the force, kinematic, power and other parameters of the rolling stock, and its movement in the railway track has not been studied enough. Classical calculation of the kinematic and dynamic parameters of the bogie's motion with the determination of the position of its center of rotation, the instantaneous axes of rotation of wheelsets, the magnitudes and directions of all forces present a difficult problem even in quasi-static theory. The paper shows a simplified method that allows one to explain, within the limits of one article, the main kinematic and force parameters of the bogie movement (installation angles, clearance between the wheel flanges and side surfaces of the rails), wear and contact damage to the wheels and rails. Tribology of the railway bogie is an important part of transport tribology, the foundation of the theory of wheel-rail tribosystem, without which it is impossible to understand the mechanisms of catastrophic wear, derailments, contact fatigue, cohesion of wheels and rails. In the article basic questions are considered, without which it is impossible to analyze the movement of the bogie: physical foundations of wheel movement along the rail, types of relative motion of contacting bodies, tribological characteristics linking the force and kinematic parameters of the bogie. Kinematics and dynamics of a two-wheeled bogie-rail bicycle are analyzed instead of a single wheel and a wheelset, which makes it clearer and easier to explain how and what forces act on the bogie and how they affect on its position in the rail track. To calculate the motion parameters of a four-wheeled bogie, it is represented as two two-wheeled, moving each on its own rail. Connections between them are replaced by moments with respect to the point of contact between the flange of the guide wheel and the rail. This approach made it possible to give an approximate estimation of the main kinematic and force parameters of the motion of an ideal bogie (without axes skewing) in curves, to understand how the corners of the bogie installation and the gaps between the flanges of the wheels and rails vary when moving with different speeds, how wear and contact injuries arise and to give recommendations for their assessment and elimination.

Monitoring the technical condition of the railway track using the method of continuous recording of dynamic processes occurring due to the interaction between rolling stock and railway track

2021 ◽  
pp. 66-82
Author(s):  
Yuriy P. BORONENKO ◽  
◽  
Aleksandr V. TRET’YAKOV ◽  
Rustam V. RAKHIMOV ◽  
Mariya V. ZIMAKOVA ◽  
...  
Keyword(s):  
Practical Importance ◽  
Stability Margin ◽  
Technical Condition ◽  
Continuous Recording ◽  
Railway Track ◽  
Lateral Interaction ◽  
Rolling Stock ◽  
Monitoring Method ◽  
Wheel Pair ◽  
Interaction Forces

Objective: To develop the method to monitor the technical condition of the railway track. Me-thods: A strain-gauge wheel pair is used for continuous recording of vertical and lateral interaction forces in a dynamic wheel–rail system. Results: Stability margin factors of a wagon relative to de-railment have been determined and the defective (prone to derailment) sections of a railway track have been identified with the exact identification of their location (GPS coordinates) on the map using navigation devices. Practical importance: The developed monitoring method makes it possi-ble to promptly re¬gister and eliminate railway track defects

Dynamic Analysis of Steering Bogies

2016 ◽  
pp. 524-579 ◽  
Author(s):  
Arun K. Samantaray ◽  
Smitirupa Pradhan
Keyword(s):  
High Speed ◽  
Ride Comfort ◽  
Lateral Force ◽  
Rolling Stock ◽  
Wheel Wear ◽  
Active Steering ◽  
Load Fluctuation ◽  
Speed Up ◽  
Turning Radius ◽  
Secondary Suspension

Running times of high-speed rolling stock can be reduced by increasing running speed on curved portions of the track. During curving, flange contact causes large lateral force, high frequency noises, flange wears and wheel load fluctuation at transition curves. To avoid derailment and hunting, and to improve ride comfort, i.e., to improve the curving performances at high speed, forced/active steering bogie design is studied in this chapter. The actively steered bogie is able to negotiate cant excess and deficiency. The bogie performance is studied on flexible irregular track with various levels of cant and wheel wear. The bogie and coach assembly models are developed in Adams VI-Rail software. This design can achieve operating speed up to 360 km/h on standard gauge ballasted track with 150mm super-elevation, 4km turning radius and 460m clothoid type entry curve design. The key features of the designed bogie are the graded circular wheel profiles, air-spring secondary suspension, chevron springs in the primary suspension, anti-yaw and lateral dampers, and the steering linkages.

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