Weight reduction of the train by applying a new construction and testing process of the train car bogie

Author(s):  
Adam Lipski ◽  
Michał Piotrowski ◽  
Stanisław Mroziński

The algorithms and procedures of the train car bogie design which have been used so far are mainly based on the iterative approach: theoretical modeling—experimental studies of entire structures, until the assumed life is achieved. Such approach usually results in over-designing of the structure and the need for numerous expensive laboratory tests. Depending on the scale and nature of the object, more or less complex research systems are used for that purpose, but in the case of primary structures of the means of transport, usually multi-axial stands are used to apply load variable in time corresponding to the input function adopted in the design process. This approach is very costly, which is mainly caused by a high cost of preparing test objects for fatigue tests and a high cost of fatigue tests performed by using multi-axial testing stands. It should be noted that because of the nature of the fatigue, drawing conclusion on the correctness of the developed structure based on individual trials is associated with a significant uncertainty. Therefore it is often necessary to perform at least a few repetitions of fatigue tests. Thus there is a need to develop the design and testing methodology for complex technical objects such as bogies of railway vehicles, in order to limit the costs of research. The paper presents the proposal of method by which it is possible to optimize weight of railway vehicle bogies while limiting of costs of research by reducing the costs of test objects and the complexity of the test stand.

Author(s):  
N. I. Popov ◽  
◽  
A. V. Suvorov ◽  
S. M. Lobanov ◽  
S. A. Michko ◽  
...  

The article describes the results of laboratory tests of the effectiveness of the disinfectant Monochloride (Iodine chloride) 2%. Laboratory studies were carried out on test objects and test surfaces contaminated with test cultures of microorganisms, which included museum cultures of E. coli (E. coli 1257), S. aureus 209-P, mycobacteria (pcs. B5), and spores (B. cereus pieces. 96). Disinfection of test objects was carried out by the method of irrigation at a consumption rate of 0,25...0,3 l/ m2 with disinfection of smooth surfaces and 0,5 l/m2, with disinfection of rough surfaces. The treatment was performed twice with an interval of 60 minutes. Our work established that the Monochloride (Iodine chloride) 2% has a high disinfectant activity against Escherichia coli, Staphylococcus aureus, mycobacteria and spores. On the basis of the laboratory work, this tool can be recommended for production tests at veterinary surveillance facilities.


2016 ◽  
Vol 8 (4) ◽  
Author(s):  
L. Pugi ◽  
E. Galardi ◽  
N. Lucchesi

The object of this work is the development of an innovative wire actuator in collaboration with Velan ABV S.p.A., which will be mainly used in applications in which high efficiency and linear behavior are desirable specifications. In this work, the main features of the proposed actuator, which is protected by a patent, are evaluated and compared with respect to a conventional solution consisting of a scotch yoke (SY) transmission system. The comparison is performed using both the simulation results and the experimental data. In order to identify the efficiency and the dynamical response of the innovative actuator, the authors have designed a hydraulic test rig, which can be configured to perform different testing procedures. In this way, it is possible to perform both static tests to identify actuator efficiency, and dynamic ones, in which an assigned load or a valve impedance function is simulated to verify the response of the tested actuator in realistic conditions. Finally, the proposed test rig has been successfully employed to perform both reliability and fatigue tests in which the actuator is subjected to realistic and repetitive loads.


Author(s):  
Yueqing Zheng ◽  
Guangwei Yang ◽  
Hailong Cui ◽  
Yu Hou

To improve the stiffness of the orifice-type aerostatic bearing, a new construction of orifice restrictor with multiple orifices in series was proposed to enhance the restriction effect. The restriction effects of the restrictors with multiple orifices in series were studied numerically. Based on a circular aerostatic thrust bearing with a central feedhole, the effect of the bearing stiffness improved by the restrictors with multiple orifices in series was studied. The results show that the aerostatic bearing with the restrictors with multiple sub-orifices in series shows higher maximal bearing stiffness than the bearing with traditional simple orifice restrictor. For example, the maximal stiffness for aerostatic bearing with the restrictor of four sub-orifices in series is 57 N/µm, which is ∼11% larger than that of the bearing with simple orifice. With this construction, the restriction effect of the orifice restrictor can be enhanced by increasing the number of the sub-orifices, instead of decreasing the aperture of the orifice. This approach avoids the difficulty of manufacturing the orifice restrictor with too small aperture for achieving a high restriction effect. The feasibility of the restrictor with multiple sub-orifices in series proposed in this paper was verified with experimental studies.


2014 ◽  
Vol 630 ◽  
pp. 99-108
Author(s):  
Andrzej Korczak ◽  
Grzegorz Peczkis ◽  
Tomasz Synowiec ◽  
Ievgenii Altyntsev

This paper presents new construction of a submersible pump which is highly efficient due to the new solutions for flow channels. It includes the results of laboratory tests of the pump of the new construction. It also presents the results of numerical calculations of liquid’s movement in the flow channels of the pump, comparison of computing characteristics and characteristics measured in the laboratory.and an analysis of the essential parameters of the pump’s work which transgression could become a danger for the pump. In case of the danger the security system turns off the engine temporally or permanently.


2007 ◽  
Vol 353-358 ◽  
pp. 142-145 ◽  
Author(s):  
Ki Weon Kang ◽  
Byeong Choon Goo ◽  
J.H. Kim ◽  
Heung Seob Kim ◽  
Jung Kyu Kim

This paper deals with the fatigue behavior and its statistical properties of SM490A steel at various temperatures, which is utilized in the railway vehicle. For these goals, the tensile ad fatigue tests were performed by using a servo-hydraulic fatigue testing machine at three temperatures: +20°C, -10°C and -40°C. The static strength and fatigue limits of SM490A steel were increased with decreasing of test temperature. The probabilistic properties of fatigue behavior are investigated by means of probabilistic stress-life (P-S-N) curve and they are well in conformance with the experimental results regardless of temperature. Also, based on P-S-N curves, the variation of fatigue life is investigated and as the temperature decreases, the variation of fatigue life increases moderately.


2017 ◽  
Vol 754 ◽  
pp. 15-18 ◽  
Author(s):  
Tamaz Eterashvili ◽  
G. Abuladze ◽  
L. Kotiashvili ◽  
T. Dzigrashvili ◽  
M. Vardosanidze

Crack propagation after low-cycle fatigue (LCF) deformation has been studied in the chromium martensitic structural steel. Although the study of a fundamental mechanism of fatigue crack growth has received much attention over the last decade, it still remains a sufficiently complex problem and needs full understanding. Moreover, the recent studies show that the cracks propagate discontinuously even on the millisecond timescale, and their growth rate significantly depends on a microstructure of the material. In the present work the boundaries of the former austenitic grains were revealed on the polished surfaces of the thermally treated samples, which subsequently were undergone low-cycle fatigue tests. The experimental studies show that fatigue macrocracks mainly grow along the boundaries of the former austenitic grains, and changetheir propagation direction when crossing the grain boundary, however, remain within 45 ̊ interval with regard the cycling axis. In particular cases, when the boundaries of a martensite packets and those of the former austenite grains lay along the length of a packet, the macrocrack is better formed and with regular borders. After a macrocrack reaches a definite length ~30-50μ, a microcrack is nucleated ahead of the macrocrack tip, and is oriented along the substructure element of the steel. Further deformation tests provide an increase in the length of the main crack via aggregation of microcracks initiated ahead of it during the LCF. In the cases when the macrocrack is deviated, slip bands are formed in martensitic structures along the boundaries of martensite packets (laths). A correlation is revealed between the microcrack components and the substructure elements of the steel as well. The same results were obtained by fractography of the tested and fractured samples. However, in the latter case correlation was established between the cleavage facets and the dimensions of packets.


2019 ◽  
Vol 11 (1) ◽  
pp. 159-172
Author(s):  
Pablo Lupera Morillo ◽  
Gary Flores Cadena ◽  
Ricardo Merizalde

Purpose – In this research paper, the electrical and radiation characteristics of a proposed fractal antenna based on the Koch curve in the second iteration for reception of digital terrestrial television signals are designed and analyzed by laboratory tests. Methodology/approach/design – The design is based on the concepts of fractal geometry and on a previously designed antenna, which is adapted to obtain a different frequency of operation; the designed antenna is constructed in three different ways, finally, they are tested in the lab using vector-network-analyzer, that allows to measure parameters, such as: VSWR, gain and radiation pattern. Findings – The fractal antenna based on the Koch curve has the necessary characteristics to receive digital terrestrial television signals in the UHF band.


Author(s):  
Sh. A. Abdreshov ◽  
◽  
A. E. Aldiyarova ◽  
E. T. Kaypbaev ◽  
◽  
...  

The scientific article is aimed at substantiating the classification of hydraulic jet pumping units, developing an experimental model of an improved hydraulic jet pumping unit, conducting experimental studies - determining the useful flow Qгн depending on the flow rate of the centrifugal pump used Qн for two variants of the pumping unit operating according to the traditional and alternative technology of water lifting, determination of the head losses hснi and friction coefficients ξснi in jet pumps, increasing the ejection coefficient Ke from the swirl parameter S of water supply to the intake chamber of the jet pump and laboratory tests of the hydraulic jet pumping unit for agricultural water supply and irrigation of pastures. The results of experimental studies and laboratory tests of an experimental model of an improved water-jet pumping unit, developed at NAO KazNAU, are presented. An analysis is given of the results of comparative tests of a hydraulic jet pumping unit for two variants of the technological process: an alternative and a traditional one with an increase in the effective supply of an alternative option by 2-4 times, a decrease in the required pressure by 1.5-2 times and an increase in efficiency by 1.1-2 times. The aim of the study is to obtain results to substantiate the classification of hydraulic jet pumping units, to carry out experimental studies and laboratory tests of an improved hydraulic jet pumping unit operating according to an alternative water lifting technology, which allows to reduce the required head of the pumping unit, increase the useful flow and increase the efficiency of the improved hydraulic jet pumping unit. The work used patent research with a review of works that were carried out according to existing methods: identifying close analogues, analyzing existing works and using them in development. Experimental studies were carried out to study the technological process of water rise from wells, the processes occurring in the used jet pumps - determining the useful flow depending on the flow of a centrifugal pump, determining the pressure losses and friction coefficients in jet pumps, the ejection coefficient and checking the reliability of the theoretical assumptions obtained. Based on the analysis of the work performed and patent research on technologies for lifting water from underground water sources by hydraulic jet pumping units and designs developed for them, a substantiated classification of hydraulic jet pumping units is proposed, which allows, depending on the task at hand, to correctly choose the necessary structural and technological scheme, type of jet pump and its implementation in the development of the required effective standard sizes of the hydraulic jet pumping unit. The scheme of the test bench and the experimental model of the improved hydraulic jet pumping unit with measuring equipment and instruments for conducting experimental research and laboratory tests on a bench well is presented.


2020 ◽  
Vol 992 ◽  
pp. 184-193
Author(s):  
S.M. Aksenova

Review of literature on heat insulation materials shows that despite significant advancements in the developing new construction materials and methods for making them, the search for, and theoretical substantiation of, novel production methods and uses in construction in line with the today’s requirements and norms remains relevant. This paper dwells upon the general patterns in creating a porous structure in a material: foaming, aggregate grouting. It presents a study of how the formula and the technology affect the properties of foam glass concrete; experimental studies described herein are designed mathematically. Emphasis is made on the materials and products made of lightweight concrete based on porous aggregates; the paper also theorizes upon making durable high-quality products and structures from those materials: blocks, stones, partitions, panels, etc.


2013 ◽  
Vol 62 (2) ◽  
pp. 217-225 ◽  
Author(s):  
Stefan Brock ◽  
Tomasz Pajchrowski

Abstract The paper presents the problem of sensorless control of a permanent magnets synchronous motor (PMSM) without a damping cage for fan applications. Frequency control was used according to the principle of v/f = const. In order to reduce the power consumption of the drive system, the optimal voltage to the motor frequency characteristics was tested in the laboratory. The experimental studies was performed on a laboratory set of a drive consisting of two coupled PMSM machines, where one machine was supplied by a transistor inverter and the other was a passive load. A new criterion based on minimizing the module of stator current vector was proposed and an optimization algorithm in steady states was tested. The results of laboratory tests confirmed the validity of the applied solution for the fan drive.


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