Wheel Pairs Research Articles

АНАЛИЗ ИЗНОСА КОЛЕСНЫХ ПАР ВАГОНОВ УЛАН-БАТОРСКОЙ ЖЕЛЕЗНОЙ ДОРОГИ

The article is devoted to the analysis of the wear of the crest of the wheel pairs of freight cars of the Ulanbator Railway. Based on numerous experimental data, the factors affecting wear are investigated. According to the change in ridge thickness, the wear rate of the first wheelset over 5000 km is less than the third, and the wear of the second wheelset is less than the fourth. Subsequent 10,000 km and 30,000 km of run, this indicator changes in the opposite direction, therefore, it is necessary to change the sequence of wheelsets.

Substantiation of rational characteristics of mechatronic control systems of position Of wheel pairs

The article analyzes the schematic diagrams of rail vehicles with radial installation of wheelsets. Radial installation of wheelsets in curved sections of the track allows for optimal interaction of wheels and rails. This interaction is characterized by minimal lateral forces in the contact of the wheels and the rails and a decrease in wear of their contacting surfaces. Requirements are formulated for the characteristics of hardware and software that will ensure the technical implementation of mechatronic control systems for the position of wheel pairs of rail vehicles in the rail track in the horizontal plane. The devices included in the mechatronic automatic control system must represent a single closed system in which the parameters of various electrical, mechanical and hydraulic processes are inextricably linked. Due to the high requirements for reliability and time constraints to the formation and transmission of the control signal to the actuators, the operation of such a system for rail vehicles should be carried out in real time. A schematic diagram of a mechatronic positioning system for wheel sets is proposed, which allows them to be optimally mounted on a railses under various conditions of vehicle movement. On the example of movement a three-axle bogie of a 2TE116 diesel locomotive in the curve, comparative calculations are made. The calculation results showed the possibility of a significant reduction in the guiding forces and minimizing the attac angles of the wheelsets of the modernized bogy in comparison with the standard design bogy.

DETERMINATION OF THE STABILITY OF FREIGHT CARS TAKING INTO ACCOUNT THE RAILWAY TRACK PARAMETERS

Purpose. For prospective speed increase in the work is aimed to consider the complex conditions of the dynamic interaction of the railway track with rolling stock. The nature and level of this interaction depends both on the design of the unit of rolling stock, its state and speed, and on the design and condition of the track itself. Methodology. Evaluation of the possible rolling stock impact on the track was investigated by the analytical method. The track stress state was determined by calculation using dependencies between force factors and the characteristics of the stress-strain state of the track. When determining the static pressure of the wheel on the rail, the influence of rolling stock skews in the rail track according to the “herringbone” scheme is considered, in which the additional lateral effect of the wheel pairs of the bogies on the track structure is maximal. Findings. When conducting theoretical studies, the dependencies of the lift resistance coefficient by longitudinal forces were obtained taking into account various types of inertia forces on irregularities both on the wheel and on the rail thread. The values of the friction coefficient in the wheel-rail contact on the movement speed were also obtained. Originality. For the first time, the rules for calculating the railway track for strength and determining the dynamic loading of the rail carriage are combined. This improvement will make it possible to calculate the structural speed of the car based on the axial loads, inertia forces due to the wheel and rails` irregularities, and also take into account the longitudinal quasistatic forces arising in the train during braking modes. Practical value. Determination of the car lift resistance coefficient using the above methodology will allow a more thorough consideration and justification of the cause of wheelset derailment. The application of this calculation method will allow us to determine the strength of the railway track and the ballast layer, taking into account the uneven load of rail threads in the case of distortions of the freight rolling stock under the action of compressive quasistatic longitudinal forces.

A Differential Electric Drive for Electric Vehicles with an Independent Power Supply

In this paper, we consider the effectiveness of using a twin-engine electric drive from the point of view of acceleration dynamics and energy efficiency. To take into account the acceleration time of the electric vehicle and the energy consumed during the transition process, evaluation criterion G was introduced. By a “twin-engine system” is meant a system of electric drive of a wheel pair through two independent mechanical channels: the first is a “high-torque” channel implemented through the use of a gearbox with a high gear ratio, and the second is a “high-speed” channel implemented through the use of a gearbox with a low gear ratio or without a gearbox at all. The summation of power is carried out by means of a differential gear. We performed mathematical modeling of the operation of such a system. Asynchronous electric drives with vector control, which operate in the torque source mode, are used as electromechanical converters. An algorithm and a system for distributing torque between two channels are developed. The gear ratio of the “high-torque” channel gearbox was optimized by the criterion of G minimum. A quantitative comparison and analysis of transient acceleration processes in single- and twin-engine systems were performed based on the example of a 30-kW electric race car. It is concluded that it is effective to use a twin engine system for specific types of electric vehicles.

ИССЛЕДОВАНИЕ ПРОЦЕССА ТЕПЛОВОГО КОНТРОЛЯ КОЛОДОЧНЫХ ТОРМОЗОВ ПОДВИЖНОГО СОСТАВА МЕТОДОМ ИМИТАЦИОННОГО МОДЕЛИРОВАНИЯ

The development of heavy speed freight train communications in the Russian Federation results in the increased thermal loading of braking system elements of rolling-stock, in particular, in shoe brakes. Taking into account the requirements of branch program documents on wheel life increase, it is evident that the further development of freight communications requires a complex application of thermal diagnostics means for auto-brake equipment of rolling-stock during a train motion. 
 The statistics shows that the fifth part of wheel pair failures is connected with thermal-mechanical damages and the situation goes on to be aggravated. In view of this hardware and software means for thermal diagnostics of shoe brakes require further improvement. The purpose of this paper is the process investigation of shoe brake thermal control by method of computer simulation and the estimate of infrared optics position impact upon control results. 
 There is considered a model for the definition of a scanning path and computation of a signal level being part of a complex simulation model of wheel thermal control. The model offered is based on the methods of solid dynamics system investigations in the basis of which there is an application of theorems on mass center motion and changes of a solid kinetic moment. 
 The model is used for finding a form and a spot area at every time moment of scanning by a solution of a problem on a dynamic spatial intersection of a wheel surface with the control area. There are considered different versions of optics orientation to an object of control for each of which for the first time there are obtained calculated thermal signals from the object under control. The analysis has shown that at the optics orientation to wheels from the outside a wheel tread appears to be in the control area that allows defining a maximum temperature of a wheel. But at the realization of emergency brake application a sharp short-time temperature increase of a tread is possible which indicates an improper operation of a brake unit. 
 The optics orientation to a wheel from its inner side allows excluding false alarm indices at emergency brake application. The correctness of the results shown in the paper is confirmed by convergence with the results of wheel heating monitoring and environmental tests of experimental complexes of thermal control means of shoe brakes.

RESEARCH OF SCALAR CONTROL SYSTEM OF TWO TRACTION INDUCTION MOTORS FROM BY ONE INVERTER

Most adjustable-speed AC drive systems are constructed in such a way that one motor receives power from one inverter and uses vector control as the basic control principle. However, in some cases there is a need to power several motors in parallel from a single inverter, that minimizes the size, weight and cost of such a system. The most common examples of such systems are rail and urban electric vehicles, where two to four induction motors are connected to drive in parallel. Control of such a system is a difficult task, especially in conditions of unbalanced loads on the motors, that can occur in conditions of different adhesion of wheels with rails. The inability to provide individual control of the motor when powered by a single inverter can lead to a decrease in the safety level of such a vehicle due to the loss of stability when changing the current value of the adhesion coefficient of individual wheel pairs. Mechanical processes in the traction system are analyzed, in which each wheel pair is driven by a separate motor powered by a common inverter. It is shown that the identity of the values of the adhesion coefficients is an important condition for the stability of such a system, that cannot be guaranteed in the actual practice of the operation of the vehicle. Therefore, the development and research of control systems that are capable of operating the system in a variety of rail / road conditions is an important direction for the further development of such systems. The structure of mathematical model of traction electromechanical system consisting of two induction motors powered by one inverter is proposed. The adjustable-speed control is based on the scalar control system, that is the easiest to implement because it does not require the estimation of the state variables of the system components. Sinusoidal pulse width modulation is selected as the switch control signal method. Operation of traction electromechanical system with scalar frequency control law is investigated by mathematical modeling. It has been proven that changing the characteristics of a single wheel pair's adhesion can lead to a loss of stability by a system that is unacceptable in terms of providing a comfortable and safe operation of the vehicle. Keywords: traction electric drive, scalar control, adhesion, mathematical model, frequency control

The reduced wear of wheel pair flanges of freight cars

Reduced wear of rails and wheels of rolling stock is a very important task of railway transport. Solving this problem not only in-creases the lifespan of wheels and rails, but often leads to a positive reduction of fuel consumption for train traction, reduces noise when the train moves in curves. The intensity of wear of rails and wheels of rolling stock depends on many factors. The practice of Ulan Bator railway shows that since 1992, the flange of the wheels has started to wear out intensively, thereby increasing operating costs to repair and reducing service life of the railcar wheel pairs. In order to determine comprehensive measures for the rotation of wheel pairs as well as to determine the intensity of wear of the flange thickness of railcar wheel pairs, experiments have been con-ducted on the wear and turning of wheel pairs of freight cars. To substantiate comprehensive measures for the rotation of wheel pairs and determine the intensity of wear of the flange thickness of the railcar wheel pairs, experimental tests on a freight car after the overhaul with the 33-mm flange thickness have been carried out throughout the year.

Statistical study of the wear of wheel pair flanges of freight cars

Reduced wear of rails and wheels of rolling stock is a very important task of railway transport. The flange profile studies were conducted to determine the machining sizes for the flange of railcar wheel pairs. The studies made it possible to determine that the rejection criterion characterizing dangerous form of the flange wear is a horizontal projection forming the worn-out surface of the flange between the points located at about 2 mm below its top and 13 mm above the average taping line. There are calculations made on the wear of the wheel pairs of gondola cars of the EC70 model manufactured in China after three years of operation.

High Frequency Vibrations Arising in System Wheel-Rail. Part I. Mathematical Modeling of the Distribution Stress in Contact Zone Wheel-Rail

This study is devoted to study of most used existing models of contact two solids, in relation solution of problem dynamic interaction of wheel pair and the rails. In paper also proposed and approbate a new relationship to connect force of interaction, deformation of local indentation, displacement of contacting bodies, their mechanical and geometric characteristics, as well as the parameters of condition during operation in different modes. The stress isolines at point of interaction wheel-rail on straight section of track without taking into account the defects of the contacting bodies are obtained.

Performance Testing of Foldable Electric Powered Wheelch

This paper aims to design and test a foldable, lightweight wheelchair propelled by a pair of electric motors. Starting from literature review, the research team carried out the design and solid modeling of proposed wheelchair. Solidworks software was used to make the computer model. The wheelchair frame comprised of a chair like frame with two pairs of wheels on front and back. The defined electric wheelchair is completed with the coordination of manual and electric system. A pair of electric motor is fitted on wheels at backside which are controlled by the electronic controller powered by the battery. The folding mechanism developed on the wheelchair was aimed for ease of transport and storage. The frame material was selected to be aluminum alloy. Lithium ion battery and geared electric motors were used in the prototype and motion control was done by joystick. Locking mechanism was used for frame locking during operation. The prototype was subjected to different tests. The unfolded dimensions of wheelchair were 850mm × 620mm × 1400mm (0.738m3) and whereas the folded dimensions were 1100mm × 620mm × 520mm (0.354m3) that resulted 52.03% reduction in volume. The mass of wheelchair was measured to be 22kg. The tested data of wheelchair was found to be 10 km approximately.

Analysis of Pressure and Dynamic Tests of the Blocked Wheel Pair

The paper describes a modular design of a wheelset. Three prototypes of wheelsets and track were manufactured using the π theorem. Full-scale wheelsets for a cargo car truck were also manufactured. The results compare the movement dynamics of conventional and modular wheel-sets mounted on cargo car trucks.

Аналіз протекторів колісних систем сільськогосподарського призначення

Пошук чинних напрямів дослідження для підвищення ефективності сільськогосподарських агрегатів, за допомогою оптимізації колісних пар, малюнка протектора та певного рівня тиску у шинах транспортних агрегатів. Попередній досвід свідчить про те, що при використанні важких сільськогосподарських машин та тракторів на полях нерідко дає негативний ефект і приводить до пагубної дії на ґрунт. В сільськогосподарський техніці використовується багато різних колісних систем. Для кожного окремого випадку наприклад для різних ґрунтів, доріг, різних погодних умов, різних агрегатів потрібно використовувати різні параметри для колісних систем. Такі параметри як: різний рівень тиску в повітряних камерах коліс, різні малюнки на протекторі колеса, змінювати висоту малюнка протектора колеса для покращення рівню прохідності. Малюнок протектора відіграє одну з найголовніших ролей в процесі щоденної експлуатації сільськогосподарської техніки. Він впливає на прохідність по ґрунту після атмосферних опадів, самоочищення та бокову стійкість. Для важкої сільськогосподарський техніці бажано використовувати такі малюнки протектора, як: «ялинка», «ключка» та багато-блоковий протектор. Встановлено, що протидіяти ущільненню ґрунту, а також там де вкрай небажано його пошкоджувати, і потрібна рівна поверхня та недопустимість дефектів використовується шини з низьким тиском. Встановлено, що залишається недостатньо досліджено вплив геометричних параметрів колісних систем та їх ефективності. У зв'язку чим необхідно розробити комплекс заходів, що спрямовані на збереження родючості ґрунтів. Таким чином треба ще звертати увагу на економічні показники використовування колісних пар. Дана проблема є досі актуальною для сільського господарства України

Modelling and parametric study of a gasketed bell and spigot joint in a buried high density polyethylene pipeline

The performance of joints in gravity flow pipelines has recently been investigated since these elements influence the longevity of the pipeline system. A variety of pipe materials and joint configurations are available for gravity applications; for lined corrugated High Density Polyethylene (HDPE) pipelines, gasketed bell and spigot joints are the commonest configuration employed in North America. The purpose of the present research study is to develop a numerical model of this joint configuration that helps improve the understanding of its behavior by capturing the kinematics of the system while buried and subjected to surface load. The model provided estimates of springline rotation within 9% of the observed angle, and vertical displacement at the joint in the crown region within 8% of the experimental data from a previous research study. Other objectives include a parametric study to assess the influence of various factors that control joint performance such as surface load position and configuration, soil properties around the pipe, and the presence of pavement. The results from the parametric study indicated that the size difference of the loading pads employed in North America had little influence on the response of the jointed pipeline. It also confirmed that the single wheel pair configuration produces some of the largest demands across the joint compared to single and tandem axle configurations. The results demonstrated the significant influence that the soil and pavement have on the kinematics demands that develop across the joint due to surface loads.

Analytical design of control system mathematical models for mobile robots based on the methods of inverse problems of dynamics and modal PID controllers

Mathematical models of a three-wheeled mobile robot based on the variable state apparatus and in the operator’s form are presented. Based on these mathematical models, the synthesis of its adaptive control system is carried out according to the method of constructing Ziegler-Nichols PID controllers, as well as modal PID controllers. The design method of proportional controllers with double differentiation (PDD) of the autonomous robot is justified. The rules of wheel pair control are synthesized on the basis of reference models using a simple gradient scheme of the inverse problems method of dynamics in the formulation of P. D. Krutko for the problem of stabilizing (blanking) the angular velocities for a three-wheeled mobile robot. Simulink-models of robot movement are developed for cases with the use of PID-controllers which are adjusted by the Ziegler-Nichols method at synchronous deviation of wheels. Simulink-models of robot motion have been developed for cases using PID controllers set up according to the Ziegler-Nichols method for synchronous wheel deflection, modal and real PID controllers for differential wheel deflection, as well as double differentiation controllers. The analysis of modeling results is considered.

Smart Vibration Sensor for Axleboxes

This article describes the actual problem for railway transport, maximum thrust without boxing. The classification for dynamic modes operation of the locomotive drive is presented. An example of a system built for locomotive is presented. It is possible to use an encoder and vibration sensor inside a smart axle-box. These sensors based on a specially domestic designed ASIC. It is shown that vibration sensors could be positioned on the cover of an axle-box. Considering this fact, one could develop a system for predicting “before boxing” state of a wheel pair. That system could be based on domestically produced electronic components. This article is about developing a smart device for railway transport, in particular, for traction vehicle. The operating principle is based on express analysis of dynamic processes in the contact of the wheel with the rail, the characteristics of which are determined by the angular accelerations of the wheel pair and forward accelerations of the axle box, i.e. the bearing housing, which is rotating in the wheelset axle.

МОДЕРНИЗАЦИЯ ХОДОВЫХ ЧАСТЕЙ ТЕПЛОВОЗА ТЭ109

In the design of modern diesel locomotives equipped with three-axial bogies both in our country and abroad there is widely used a spring hanger made as cylindrical spiral springs of compression with the use of hydraulic shock absorbers. At that the boxes of wheel pairs are connected with frames with the aid of carriers. 
 A considerable drawback of such bogies is that these designs do not allow obtaining the angular turn of wheel pairs during their motion along curvilinear areas of a railway. That is why in practice an increased wear of wheel flanges of wheel pairs takes place. In Bunin SU of Yelets at the level of the invention (RU2604924) there is developed a promising design of a spring hanger excluding such a drawback and a series of computations for substantiation of its efficient design parameters. The investigation results are recommended by research and industrial companies in the field of heavy engineering both in our country, and abroad with the purpose of the further study of the design developed and its possible introduction in practice.

Расчет ресурса изнашиваемого оборудования электропоездов серии ЭС2Г

The article discusses the impact of operating conditions on the wear of the wheels for ES2G electric trains. Thanks to the information on the controlled parameters of the wheel pairs (rolling, flange thickness and rim diameter) of ES2G electric trains operated by the MCC (Moscow Central Circle ) and the Oktyabrskaya Railway, a comparative analysis of the wear surface intensities of the rolling surfaces for seamless-rolled wheelsets has been performed. The analysis of the dependences of the mathematical expectation for the controlled parameter on the operating time showed that the wear rate of the rim for the electric trains operated by the MCC is 2,9 % higher than by the Oktyabrskaya Railway. Similar results were obtained for milling bar (2,33 % ) and the ridge thickness (24,3). Based on the results , it was concluded that the wheelsets wear of the ES2G series electric trains differs significantly in the two compared sections of circulation. Electric trains serving the Oktyabrsky direction has the intensity wheel pair wear lower than the trains serving the MCC. This will allow more time before turning to restore the profile of the rolling surface. The estimated value for the durability indicator of 90 % of the resource before changing the wheel pairs for the maximum wear of the rim is 2 million km at the MCC and 4.4 million km at the Oktyabrskaya Railway.

Evaluation of the wear of the tire wheel pair at rolling friction

Evaluation of the wear of the tire wheel pair at rolling friction

ОСОБЛИВОСТІ ВИПРОБУВАННЯ НА МІЦНІСТЬ АВТОРЕГУЛЯТОРІВ ГАЛЬМІВНОГО ОБЛАДНАННЯ ПАСАЖИРСЬКИХ ВАГОНІВ

The automatic regulator РКЗТ-675 (РТПР-675) and РТПР-675M is installed in the brake lever transmission of the passenger car and used for automatical maintenance of gaps between the surfaces of rolling of wheel pairs and brake pads within the established limits irrespective of the wear of the rolling surfaces of wheels. The design of auto regulators allows you to change the stroke of the piston rod and the brake cylinder and to manually release and tighten the regulator. Scope of auto regulators: freight, passenger cars and electric trains of the main railways. The article is devoted to solving the problem of contradictions in clause 15.5.7 of the current departmental Ukrainian instruction ЦЛ-0013 for repairing brake equipment of the railway carriage of the existing requirement for mandatory compliance with screw unscrewing in size "a" within 300-350 mm when testing automatic regulators on an automatic test stand for strength under load a normalized force of 8t in the longitudinal direction, provided that there are no residual deformations of the automatic regulator screw along its length. The article aims to refute the dependence of the values of the stress state of an automatic regulator when testing its strength on a test bench from a change in its length in the entire possible range of screw unscrewing by size "a" in the allowable range of 0-600 mm. The problem is solved by calculation using two different methods, and the results of the stress state values of the automatic regulator with different lengths of screw unscrewing by size “a” are compared with each other. Based on this, the general conclusion is made that the size “a” (within the range of 0–600 mm) of the automatic regulator screw unscrewing when testing it for strength with the same load force (N = 8t ≈ 80 кН) in the longitudinal direction does not affect the calculated value of the screw tension σ = 113.23 MPa when tested on an automatic bench. The developers of the departmental Ukrainian instruction ЦЛ-0013 are invited to make in clause 15.5.7 corresponding changes regarding the requirement of optional observance of the value of the size "a" within 300-350 mm at the bench test of the automatic regulators for the tensile load under the standardized force of 8t.

Development of solid anti-friction elements for greasing the ridges of locomotive wheel pairs

Design work was carried out to develop solid anti – friction elements for greasing the ridges of locomotive wheel pairs (hereinafter referred to as TAEL rods). The results of laboratory bench and operational tests of TAEL rods were obtained in accordance with the procedure for admission of lubricants for the wheel-rail contact to use in grebnesmazyvatelyami lo-comotives operated on the Railways of the Russian Federation . Based on the test results, the developed TAEL rods were approved for use on the infrastructure of Russian Railways.