Gondola Car Research Articles

INFLUENCE OF LATERAL DISPLACEMENT OF BOGIES ON THE FREIGHT CAR DYNAMICS

Purpose. The work is aimed at determining the influence of the lateral displacement of a freight car bogie, taking into account the value of the movement speed on its main dynamic indicators and interaction indicators of the rolling stock and the track. Methodology. The quantitative assessment of dynamic indicators was obtained by the method of mathematical and computer modeling. The design scheme of the car takes into account the interaction peculiarities of cars as part of the train: the possibility of all modes of body vibration in space, the transmission of longitudinal force from neighboring cars in vertical and horizontal directions, taking into account the technical condition of individual parts of the car and their design features, as well as various operating conditions. Findings. During the research, a mathematical model of a coupling of five freight cars was applied to study the dynamic loading of a gondola car and a track. Main dynamic and interaction indicators of the rolling stock and the track in case of transverse bogie displacement when moving along curved track sections assessment were assessed. The maximum possible values of the lateral displacement of the freight car bogie were substantiated. Originality. The mathematical model of the coupling of freight cars in the train has been improved. In the calculation schemes describing the vibrations of the cars, the peculiarities of the freight car bogies, lozenging of the bogie side frames are taken into account. The model makes it possible to study the effect of changing rotation angle of the central axis of the car body, which in turn leads to the lateral displacement of bogies relative to each other, on the main dynamic and interaction indicators of the rolling stock and the track. For the first time, the influence of transverse displacement of the bogie was investigated, taking into account the wear of its parts and assemblies when moving on track sections with unevenness. Practical value. The calculation results can be used to assess the influence of the bogie transverse displacement on the dynamic qualities of the rolling stock and interaction indicators of the rolling stock and the track, taking into account the wear of parts and units of the bogie when moving in straight and curved track sections with irregularities. The application of the results obtained will contribute to an increase in the stability of freight rolling stock in the conditions of increasing travel speeds, which in turn will allow developing technical conditions for the implementation of resource-saving technologies for transporting goods that meet the safety requirements of train traffic.

Research on stress intensity factor and fatigue crack propagation rate of the general-purpose gondola car body

In order to study the crack propagation characteristics of key parts of the general-purpose gondola car body, according to the structural characteristics and crack statistics results of the car body, the floor along the cross bearer weld was taken as the research object. The stress intensity factors under different conditions of the floor were studied, based on linear elastic fracture mechanics and finite element analysis. In addition, the crack propagation rates of the floor were studied by the Paris formula. These research results will provide a reference not only for formulating maintenance procedures for the general-purpose gondola car body, but also for evaluating the safety and reliability of wagon bodies.

Research of the Vertical Dynamics of the Supporting Structures of Freight Cars Made of Round Pipes

Purpose. This study is aimed at determining the vertical dynamics of supporting structures of freight cars made of round pipes. Methodology. Mathematical modeling of the dynamic loading of the supporting structures of the main types of freight cars made of round pipes (gondola car, covered car, flat car, hopper car) was carried out. The studies were carried out in a plane coordinate system – the XZ plane. At the same time, it was taken into account that the car is moving in an elastic-viscous track so that the reactions of the track are proportional to both its deformation and the rate of this deformation. The studies were carried out for the case of empty cars. The joint inequality is described by a periodic function. The calculation was performed at a speed of 80 km/h. Differential equations of motion were solved in the MathCad software package using the Runge-Kutta method. Findings. Based on the mathematical modeling of the dynamic loading of the supporting structures of cars made of round pipes, the main indicators of their dynamics were obtained: accelerations acting on the supporting structures in the mass center, forces acting in the spring suspension of bogies, dynamics coefficients. For gondola car, covered car, and hopper car, the acceleration at the mass center of the supporting structure is within 0.4 g, and for a flat car – 0.5 g. It was found that the obtained indicators of the dynamics of cars made of round pipes are within the permissible limits. The accelerations acting on the supporting structures of cars made of round pipes are almost the same as those obtained for prototype cars. At the same time, the motion of cars is assessed as "excellent" for gondola car, covered car, and hopper car and "good" for flat car. Originality. Mathematical modeling of the dynamic loading of the supporting structures of cars from round pipes was carried out and the main indicators of their dynamics were obtained. Practical value. The research carried out will contribute to the creation of recommendations for the design of supporting structures of freight cars of round pipes, and can also be useful developments in the creation of innovative car designs.

Method for determining non-uniform loading of gondola cars with bulk cargo

Methods of loading gondola cars with bulk cargo are considered and possible types of non-uniform cargo distribution in the car bodies are established.The most common methods of levelling bulk cargo in gondola cars in the Ukrainian railway network are determined. Designs of equipment for mechanization of levelling bulk cargo in gondola cars are presented, their advantages and disadvantages are considered. Based on the given analysis, it is established that the most efficient way to ensure compliance with the current regulations on the placement of cargo in cars is the timely detection of non-compliance with these requirements at the stage of loading.The analysis of existing methods for determining the non-uniformity of cargo distribution in the car bodies was conducted. Based on this analysis, a new method for determining the nonuniform distribution of bulk cargo in the car bodies is proposed, which can be used to preestimate the compliance of the actual placement of bulk cargo in the car body with the requirements of current regulatory documents immediately after loading and take prompt measures to eliminate the identified inconsistencies.

Проблемные аспекты в реализации информационной технологии «Автоагент» на железнодорожном транспорте (на примере Восточно-Сибирской железной дороги)

The article presents the technology of the railway divisions in handling the automatic registration of shipping documents for transportation of empty gondola cars in domestic traffic (“Autoagent”). Regulatory and technical documents defining the procedure for the implementation of the technology are studied in detail, and some setbacks in the registration of transportation documents based on paper medium are identified. The “Autoagent” system failures after updating the AS ETRAN program, which is in constant operation on the East Siberian Railway, are determined and analysed. Conclusion on the implementation and improvement of the experimental technologies and various programs that are in constant use are made.

Четырехосный полувагон грузоподъемностью 60 тонн с деревянной обшивой кузова 1947 года, модель 12-37

The authors of the article continue to publish materials on the development and design of car structures and their elements at the Ural railway car building plant. The results of the work for the period from 1936 to 1941, during which the design-engineering bureau of the Ural railway car building plant (Uralvagonzavod) developed more than 30 freight car projects, are presented. The device of a gondola car with a wooden covering with a new numbering of schematic drawings, with the assignment of the model number according to the type 37.00.000-0 is given. The elements of the gondola car that differ from the previous design are considered in detail: the overall size, side walls, ridge beam and its elements, bogie, automatic coupling and brakes, and others. The technical characteristics of the gondola car are given

Improving the Methodology for Calculating the Average Turnover of Gondola Cars of an Iron and Steel Plant

The average daily mileage of a wagon, its productivity and turnover determine the level of efficiency of rolling stock use. The car turnover is calculated and normalized not only for the fleet as a whole, but also for each type of rolling stock, for a particular region and road, depending on the nature of the transportation work. Accelerating car turnover increases its productivity and increases profit of an operator company. At the same time, its decrease negativ ely affects the capacity of the infrastructure, entails an increase in the cost of shunting and train work, which means that it will increase the cost of transportation. In modern conditions, turnover is determined for each participant in transportation in accordance with his area of responsibility. For an iron and steel plant, the use of an optimal methodology for recording the time spent by a wagon on its tracks allows us to adequately assess this important quality indicator, as well as to monitor its change as a result of introduction of new technologies for transport maintenance of workshops, reconstruction of station layout and optimization of the transportation process. The objective of the study is to improve the methodology for determining car turnover on access roads of a metallurgical enterprise for universal rolling stock in the context of dual operations. The authors use general scientific methods, mathematical methods, comparative analysis. This article presents the main provisions of the methodology, which will allow determining turnover of gondola cars subject to a single or dual operations in the form of a single indicator which is average weighted car turnover.

Structural optimization of the heavy haul wagon body based on MPSO-BP algorithm

Fatigue cracks usually occur at the welded joints of the heavy haul wagon body. To effectively limit the occurrence of such problems at the design stage, this study moves from the structural design strategy to the structural optimization method. First, when analyzing the results of the finite element simulation, the new structural design strategy not only considers the maximum stress, which can reflect the stress concentration position, but also focuses on the stress distributions at the key welded joints. Second, in order to further reduce the stress at the key positions, the study presents an optimization method that integrates an orthogonal experimental design, BP network, and MPSO algorithm. Finally, an 80 t gondola car body is optimized from the whole structure to the local area by the proposed method. Further, it is also verified that the structural optimization method of the heavy haul wagon body is reasonable and feasible.

Research of dynamic indicators and influence of different types of rolling stock on railway track

The technical level of rolling stock of railway transport directly affects the economic indicators of the transport industry and the economy of the country as a whole, which leads to the need for improvement of the control, quantitative assessment of the dynamic loading o f rolling stock to ensure safe and reliable communication at the railways. Therefore, in the process of designing and operating the rolling stock the quantitative assessment of dynamic loadings is a relevant scientific and technical problem. The purpose of this work is to study the influence of different types of rolling stock, taking into account the speed of movement on their main dynamic indicators and indicators of interaction of track and rolling stock. The basis of the research is the method of mathematical and computer simulation of the dynamic loading of a freight car using the model of spatial variations of the coupling of five cars and a software complex developed in the branch research laboratory of dynamics and strength of rolling stock (BRL DSRS). Theoretical studies have been carried out under condition of movement of several types of freight cars: a gondola car of the model 12-532, a hopper car for coal transportation of the model 12-4034 and a flat car with a long cargo of the model 13-401 and typical bogies 18-100 with the speeds from 50 to 90 km/h in the curves with radii 350 and 600 m, with superelevation 130 and 120 mm, correspondingly.

Calculated studies for the braking efficiency of freight trains under the rules of gost 34434-2018 with the application of universal formulas (four-axle gondola cars, covered railraod cars, platforms, dump cars)

Absence of normative values of the actual coefficients in new rules of GOST 34434-2018 does not allow implementing and determining the optimal characteristics of the brake according to the previously adopted conditions of braking efficiency (braking distance), which causes uncertainty in solving this problem. The uncertainty lies in the fact that the choice of the characteristics of the brake system of a freight car has to be carried out by enumerating a large number of variations. In this respect, the article provides tools for determining the actual coefficient of the press force of composite brake blocks on  wheels, satisfying the given braking efficiency of the freight train. Universal formulas are used as tools in the form of power dependence between the actual coefficient of press force of brake blocks and the braking distance of a freight train. The coefficients of universal formulas are obtained on the basis of computer simulation. Numerous examples show that the error in the use of universal formulas in calculation studies does not exceed 0.5% compared to the calculated ones according to GOST 34434-2018 methodology. Values of actual coefficients are given depending on the axial load of the car and speed at which the braking distances of the freight train correspond to the standard minimum permissible values. It is shown that performance of the calculation studies using universal formulas in the EXCEL environment allows automate the calculation process in full. A technique is proposed for determining the gear ratio of the brake lever mechanism of a freight car, at which a given braking efficiency is performed. The proposed technique allows you to perform multivariate studies on the selection of optimal parameters of the brake system of freight cars that meet the specified requirements for braking efficiency, and greatly facilitates the calculation studies.

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.

РАЗВИТИЕ МЕТОДОВ АНАЛИЗА ПРОЧНОСТИ И НАДЕЖНОСТИ НЕСУЩИХ КОНСТРУКЦИЙ ПОДВИЖНОГО СОСТАВА С ИСПОЛЬЗОВАНИЕМ МЕТОДОВ МАТЕМАТИЧЕСКОГО МОДЕЛИРОВАНИЯ

The purpose of the work is a procedure formation for the analysis of strength and reliability of rolling-stock bearing structure using methods of mathematical modeling. Its appraisal is shown by the example of improvements in a universal gondola car bearing structure. The procedure offered is formed by a mathematical modeling of bearing structure dynamic loading in the rolling-stock operation including shunting movement encounters. At the first stage of the procedure the dynamic computer simulations of a rail crew movement on way roughness are under development. As a result of modeling there are defined dynamic loads influencing a bearing structure in operation. The analysis of the stress-strain state of the bearing structure is carried out on the basis of detailed shell finite element models. The computation is carried out in a dynamic position through the method of the direct integration of nodal-relocation equations. The estimate of bearing structures fatigue life in a pivot area was carried out on the basis of the linear hypothesis of fatigue damages summation, the power approximation of a material fatigue curve and scheming dynamic stresses affecting the structure through the method of complete cycles. 
 Within the limits of the procedure the history of loading was presented as a step function. On the basis of the results of a stress-strain state in the bearing structure of a gondola car body in a static and dynamic location there is carried out the analysis of fatigue life in a pivot area of the gondola car and the conclusions were drawn regarding crack-like defect occurrence in a center plate arrangement of a frame. 
 There are offered three versions for updating the pivot joint of a gondola car with the purpose of its fatigue life increase. For each version of updating there are developed corresponding detailed finite element models of the pivot area and on their basis the analysis of strength and fatigue life is performed. 
 On the basis of computation results and taking into account the manufacturability of center plate arrangement production an efficient version is recommended for updating a pivot joint of a gondola car. The pivot joint modernization according to the version offered allowed decreasing maximum acting stresses in the pivot joint by 27% and increasing service life of the welded joint elements up to 29 years.

GONDOLA CARS DYNAMICS FROM THE ACTION OF LONGITUDINAL FORCES

Purpose. The aim of the work is to study the influence of longitudinal quasistatic tensile and compressive forces in gondola cars arising at stationary and transient modes of train movement on their main dynamic indicators and interaction indicators of rolling stock with a rail track, taking into account the possibility of speed increasing. The relevance of this study is related with the need to control the longitudinal forces arising during stationary and transient modes of train movement, with increasing speeds, masses and lengths of trains, especially freight ones, increasing the locomotives` power. Methodology. The main method for studying the dynamic loading of a gondola car on typical three-element bogies is mathematical and computer modeling of the interaction of rolling stock and track structure based on the model of spatial vibrations of freight cars` couplings. In a theoretical study, the influence of quasistatic longitudinal tensile and compressive forces is considered depending on the change in speed and the force value on the tension of 1 MN; 0.5 MN; 0 and before compression of 0.5 MN; 1 MN. Findings. As a result of theoretical studies and after modeling, taking into account the processes of oscillation of gondola cars under the action of quasistatic longitudinal forces limited by norms to ± 1MN (100 tf), the dependencies of the main parameters normalized by technical documentation are obtained taking into account the value of the movement speed. Originality. The influence of longitudinal compressive and tensile forces on the dynamic loading of a freight car is studied in order to solve the problem of forecasting the dynamics of rolling stock, taking into account the value of the speed along curved track sections. Practical value. Application of the results obtained can increase the stability of freight rolling stock and the strength of the railway track, which in turn will remove some existing restrictions on permissible speeds and increase the technical speed of trains. The obtained dependencies of the main normalized indices on the longitudinal quasistatic force will make it possible to predict the development of deviations and prevent their transformation into the dangerous ones for train movement.

Study on Key Technology of Railway Freight Car Body Fatigue Test

Car body fatigue reliability is a key technology for the development of railway heavy axle load freight cars. Therefore, a comprehensive test rig capable for carrying out car body fatigue test and complete car vibration test was designed and built in CRRC Qiqihar Rolling Stock Co., Ltd. (QRRS). This test rig was used to validate fatigue life of car body in accelerated fatigue test by simulating car body movement in service with input data derived from measurements in service lines. The success of such test depends on some key technologies such as collection of response signals in service line test, process of data collection, compilation of drive file for test rig, determination of test methods and evaluation of test results. A C70E-loaded general service gondola car was tested on test rig to evaluate its fatigue life with accumulated equivalent total mileage of 3.125 million kilometers. The test results indicate that this car body can survive for 25 years and meet designed life requirement. Comparison between response signals from test rig and target signals demonstrates that acceleration RMS error is less than 6%, and stress RMS error is less than 18% and fatigue accumulated damage error is less than 6%. It means that simulation accuracy of test rig has achieved the requirement. Such results demonstrate that related key technologies are applicable and suitable.

Mathematical model of spatial vibrations of a four-axle gondola car on bogies with elastic coupling of wheelsets and side frames

Mathematical model of spatial vibrations of a four-axle gondola car on bogies with elastic coupling of wheelsets and side frames

Analysis and prospects of container and rail transport

The article studies the main trends in the market of container transportation in rolling stock of various types, considers the process of transporting large-capacity containers in open wagons. The operational and economic aspects of removing administrative restrictions on the implementation of this type of transportation are noted. The dynamics of rental rates for rental of gondola cars and platforms in 2019-2020 is present. The summary characteristics of the gondola car fleet and fitting platforms on the Russian Railways network have been study. The analysis of the market share of the largest owners of gondola cars and fitting platforms was carry out. The advantages and disadvantages of using the technology of container transportation in open wagons are list. Solutions are propose to create a competitive environment in the container transportation segment of the transport services market.

Конструкции полувагонов 1937–1941 гг. и их модернизация

The authors of the article continue to publish materials on the development and design of gondola structures at the Ural car building plant. The article is devoted to the development of a gondola car by the Ural design Bureau in 1937 and its subsequent modernization. The design elements of the gondola car that differ from the previous model are considered: size, trolley, automatic coupling and brakes, manhole cover, parameters of the gondola car, etc. The results of the work of the Interdepartmental Commission are presented. A new design is considered: coupling buffer beam and the connection of the beams with the lower belt, the constituent elements of the cross section of a center girder and corner posts, etc.

Study on the Strength of 35t Coiled Steel Pallet for 100t Gondola Car

The Coiled Steel safety transportation has become an important part of railway freight transportation. Due to the special shape and heavy-weight of coiled steel, loading and reinforcing is very complexity, Displacement or rolling is much more likely to happen in transit. It will lead to eccentric loading, unbalanced loading, freight vehicle damaging, or serious accident due to coiled steel falls down from freight vehicle. At present, the coiled steel produced are larger in weight, larger in diameter and wider in plate width, with a maximum weight of 35t. The 100t gondola car is generally C100 and C100 A. It has the advantages of longer length, larger load and larger capacity in the middle. It is the best choice for loading larger weight coiled steel. This paper used SolidWorks to build the model according to the design structure of the special coiled steel pallet for loading 35t coiled steel on 100t gondola car. Then the stress distribution of the pallet is obtained through the strength simulation experiment. The results show that the maximum stress of the pallet occurs at the ribs in the middle of the clamp on the side of the pallet, which exceeds the allowable stress of the material. Finally, the pallet is optimized to meet the actual transport requirements.

Assessing the stopping brake retention guarantee for an innovative gondola car on the standardized down grade with a 27 t load from the wheelset to the rail

Assessing the stopping brake retention guarantee for an innovative gondola car on the standardized down grade with a 27 t load from the wheelset to the rail

A finite element analysis on mechanical behavior of Al/Al-Mg composites for the design of tank cars under actual measuring loads

The transportation safety of tank cars carrying concentrated nitric acids under conditions of heavy loads has attracted the increasing attention. The use of Aluminum/Aluminum-Magnesium(Al/Al-Mg) alloys to form laminated composites can solve the problems associated with the low corrosion resistance and strength of tank car bodies. In this work, a finite element analysis was used to simulate the tensile tests of the Al/Al-Mg laminated composites. In particular, the stress and strain behavior of the composites under tensile loads was investigated, and the corresponding mechanical properties of the composites were determined, which was verified by the tension test results. Furthermore, the effective load time history was obtained by processing the measuring data of C70E type gondola car body on three typical general railway line. Load spectra of car body were compiled using the rain-flow count method, which was applied to do the fatigue design for 70 t Al/Al-Mg tank body. Most importantly, in conjunction with the SN curve of the base materials and the lap-welded joint, based on the tank car finite element analysis results under various load cases, the fatigue life of the 70 t Al/Al-Mg tank body was calculated based on Miner's linear accumulative damage theory. The results showed a very promising application of such composite materials to meet the safety requirements.