Cost-effective technology of temporary setting trains aside from the traffic

The article determines main factors of the need for modern conditions of temporary setting aside trains from the traffic, which require consideration of this operation not as an emergency forced measure, the need for which arises because

of operational personnel errors, but as one of the elements of the transportation process technology that require it rational organization. These factors are: formation of large unloading areas in seaports taking into account recurring difficulties in its work, technical equipment failures and traffic safety violations, daily irregularity of train operation, etc. Principles of building a rational strategy for temporary setting aside trains from traffic are considered. It makes provision for: using the capabilities of the operaoperational area infrastructure as a whole for set aside trains, impermissibility of reducing the carrying capacity of previous sections of the difficult section below its carrying capacity as a result of set aside trains, selecting stations for set aside trains based on feasibility studies.

Use of a cost-effective strategy for the temporary setting trains from traffic in the event of operational difficulties will minimize the expenses of the JSC “Russian Railways” related to the need to carry out this element of the transportation process

technology.

Accounting power supply schemes for traction substations in the calculation of short circuits in the AC traction network

When calculating short-circuit currents in the AC traction network, it is assumed that each of the traction substations receives power from uncoupled external power supply sources with known resistances. In some cases, especially when powering

a group of traction substations from a high-voltage power line of a longitudinal power supply, the external power supply system affects not only the magnitude of short-circuit currents, but also their redistribution between adjacent traction substations of the interstation area where this circuit is considered. Such unrecorded redistribution can have a negative effect on short circuit protection.

The article considers the equivalent circuit of the traction network, taking into account resistance of the external power supply system. Particular attention is paid to the fact that in replacement circuits of direct and negative sequence value of reduced resistance of one phase of a multiwinding transformer, calculated from the

short circuit voltage, does not depend on the connection scheme of its windings. It is noted that in some cases it is difficult to obtain a complete scheme of an external power supply system. Considering that the short circuit in the traction network for the external power supply system is remote, it is proposed taking into account the reference network or traction substations as power sources, from which high-voltage transmission lines power the traction substations. Resistance of the supporting substations as power sources must takes into account connected equivalent power system.

Such equivalenting should be carried out by known values of currents or short-circuit powers at the inputs of the reference substation or, if such information is not available, by the rated values of the switched-off currents or powers of the switches of high-voltage line connections. The following power schemes for traction substations are considered: each from its own supporting substation, which is part of an electrically uncoupled external power supply system; from the double-circuit high-voltage line of longitudinal power supply when it is powered from different supporting substations; from the supporting network substation, the traction substation receives power from two lines, and from this the traction substations receive power from two lines in a circle pattern.

These three common cases cover all the most common power schemes for traction substations. For each of them formulas are given to determine the resulting equivalent resistance of the external power supply circuit, which should be taken into account in the replacement circuit of the traction network.

Results of comprehensive studies conducted by the Central Research Institute (VNIIZhT) and construction work of the Ministry of Railways (RZD) to increase the loading gauge of freight and passenger rolling stock on the railways of Russian Federation

The article presents the content and results of a set of studies on the scientific and methodological support for the modernization of structures and devices built according to the old loading gauge standards or its expired durability, the entire 1520 (1524) mm gauge railway network under the loading gauge standard T for rolling stock, allowing to increase axle and running loads of cars and due to this —

the mass of trains, as well as solve the global problem that arose in the middle of the last century to increase the efficiency of the most important branch of Russia — railway transport. Variants of increased loading gauges were developed (Тпр for any rolling stock, Тц for tanks, Та — for electric rolling stock, Тб — for passenger cars), which were included in the GOST 9238 – 83 “Loading gauges of railway rolling stock and structure clearance” and Ministry of railways instructions (no. TsP/4425 — for clearance of structures; no. TsV/4422 — for loading gauge of the rolling stock and no. TsD/4172 — for transportation of oversized and heavy  (nonstandard) freights), as well as zonal and flatcars loading gauges. Scientific and methodological studies carried out by the institute during the half-century period (mid-XX — early XXI) identified structures and devices that limit the use of rolling stock of loading standard T, its elimination during 1982 – 2005, as well as transition of industrial enterprises to the production of new freight and passenger cars of increased loading standards Тпр and Та, developed by the Institute. This identification was made on the basis of the overall classification of all railway infrastructure and access railroads of the former USSR. New regulatory framework

for railway rolling stock loading gauges and structure clearance (GOST 9238 – 2013) was developed based on a global survey of actual dimensions of all structures and infrastructure devices of the 1520 (1524) mm gauge railways (area 1520). Railway Research Institute of the Ministry of Railway Transport (currently, JSC “VNIIZhT”) made scientific and methodological support for the modernization of infrastructure objects, exhausted its life span for the 100-year period of operation. Scientific and methodological support carried out by the Institute allowed the creation and operation of rolling stock with an increased loading  gauge standard Тпр: for freight traffic — with increased running loads by 2 ton/m or more compared to European railways; for passenger traffic — more comfortable and 39 % more spacious double-deck compartment cars. Increasing the loading gauge of the rolling stock provides increased efficiency of rail transport by increasing productivity, reducing the required fleet of cars for the transportation of equal volumes as well as operating costs. At the same time achieved annual total economic effect amounts to 2,205 billion rubles. Introduction of the flatcar loading

gauge contributes to the organization of transportation of heavy trucks by rail and, therefore, improve the environmental situation.

Operation results of reversible converters of AC electric locomotives VL80R on the Krasnoyarskaya Railway

The article presents information about faults of reversible converters (RC) of AC electric locomotives of the VL80R series, fixed at the maintenance points of locomotives and locomotive depots of the Krasnoyarskaya Railway for the period 2014 – 2018. Authors provide data on the number of semi-conductor switches, their main parameters and technical characteristics for two types of converters — RC-2200 and RC-4000 operating on VL80R electric locomotives. Their influence on the RC construction scheme is shown. Revealed the causes of failures of the RC in the operation of electric locomotives. The role of maintenance of RC in electric locomotive and its monitoring system in ensuring reliable operation is shown as well as the statistical data on the quantitative and qualitative assessment of the types of failures of the RC. The article also shows statistics of changes in the number of converters of each type during the operation of electric locomotives. Information is given on the number of all faulty RCs on VL80R electric locomotives and an analysis of faulty RC-2200 and RC-4000s for a specified time period. The data is presented on the number of RC-2200 and RC-4000 failures per million km of the VL80R electric locomotive in terms of one section. Authors carried out analysis of statistics of this type of failure of the RC with reach-through breakdown of the shoulder. Information is given on the number of RCs with the reach-through breakdown of RC shoulders per million km of VL80R electric locomotives. It was concluded that for the period from 2014 to 2018, the number

of failing RCs due to dangerous shoulder punctures decreased significantly, which led to a significant reduction in the number of failures of electric locomotives due to this failure. So, for RC-4000 this decrease occurred 5.75 times, and for RC-2200 2.4 times. In addition, the reason for a more significant reduction in the number of

failures of electric locomotives with RC-4000 due to its faulty, is that RC-4000 is more modern and contains much fewer semi-conductor switches and additional elements. This increases the reliability of the RC. Thus, the replacement of obsolete RC-2200 with modern RC-4000 provided a reduction in the total number of faults of all RC in 2.3 times; decrease in the number of cases of RC failures per

million km of a locomotive in 4 times.

Methodology for calculating financial result for the owner of the infrastructure from increasing carrying capacity of the direction during operation in cars with increased capacity

In accordance with the draft Long-Term Development Program of the JSC “Russian Railways” until 2025, the main  driver of growth in freight turnover in this perspective will be a further increase in the transportation of hard coal. It will occur both due to the growth of coal production in Kuzbass and due to the development of new coal deposits. For the period up to 2025, the increase in coal loading by 4 – 5 % per year is predicted on rail transport. Under these conditions, it becomes necessary to increase the capacity of the transport complex, especially the carrying and transport capacities of the Eastern Operation Area.

The article presents the methodology for calculating economic effect of increasing the carrying capacity of the site during operation in cars with increased axle load. The scope of this methodology is specific areas (sections), taking into account their technical, operational and economic parameters.

Variant calculations were made, the results of which showed that an increase in the carrying capacity of a section with an increase in the mass of a train formed from cars with increased axle loads does not always give a significant positive effect in terms of value for the infrastructure owner.

Positive effect of the increase in carrying capacity in the form of additional profits from the additionally used traffic volume in the evaluated variant can be taken into account in the following cases:

• operation of large-capacity cars on freight-intensive sections where there is a lack of carrying capacity in the billing period, i. e. the carrying capacity of the section is less than its required value;

• exceeding the freight charge for the additional volume of freight carriage incurred transportation costs, i. e. if the tariff compensates for at least the dependent part of the cost of additional volume transportation.

Positive economic effect of the increase in carrying capacity in the form of increased money flow is achieved if the profit from the additional traffic volume in the direction exceeds the additional costs associated with changing the technology for servicing the traction arms while promoting high-weight trains formed from cars with increased axle loads. In other words, if there is no increase in the value of the indicator of mileage (in section-km) per unit of transport work, and the unit cost of maintaining one section with a new technology for servicing traction arms.

Modelling car motion and the calculation of the wear of wheels with the VNITsTT rolling surface profile

The wear problem of wheels along rolling surface or thin flange is currently involved a large circle of specialists. There are opinions that it is necessary to establish new limit values for wheel wear in operation, put into practice the re-profiling (profile grinding) of rails, install a larger number of floor-mounted lubricators in places of increased rail wear intensity, but one of the priority direction in this area is the development of a new surface rolling wheel profile for freight cars, the use of which will help to increase the turnaround time and increase the service life of the wheels in operation. Geometry of the rolling surface profile of the wheel should allow to provide a contact form between the wheel and the rail conformal or close to conformal. This solution has already found its application and achieved desired results on foreign railways (North America, South Africa, China, etc.). Authors developed a technique for designing a new wheel profile, which was used to build a profile of the rolling surface made by the Russian Research Center for Transport Technologies (LLC “VNITsTT”). As part of the study, calculations were carried out using the method of mathematical modeling of a freight car motion in the MEDYNA software package and performance indicators were evaluated on the VNITsTT rolling surface profile in comparison with the profile made according to GOST 10791 – 2011, and the wheel wear rate produced on the section of the track close to the average network operating conditions. Additionally, critical speed of the sinuous motion of the car was evaluated, which showed that despite the increased equivalent taper, the critical speed remained almost unchanged (an increase of 6 %). Theoretical calculation of the wheel resource based on the results of mathematical modeling has been made. According to the calculations, it was determined that the resource of the flange before turning for the RDCTT profile is 409.3 thousand km, and for the rolling surface — 663.3 thousand km, for the profile made according to GOST 10791 – 2011, the resource for the flange was 285.6 thousand km, and for the rolling surface 401.2 thousand km. Thus, the use of the VNITsTT profile is more effective than the profile made according to GOST 10791 – 2011 by 30.2 % for the flange and 39.5 % for the rolling surface. The developed VNITsTT profile, in comparison with the profile made by GOST 10791 – 2011, according to the results of calculations, confirmed the provision of standard indicators of the dynamic qualities of a freight car.

Test results of the resonant single-wire power transmission system for induction heating of the switch rail

The article provides results of tests of a resonant single-wire power transmission system for induction heating of a switch rail in the organization of train traffic in difficult winter climatic conditions.

Laboratory tests have shown the possibility and feasibility of applying heating by an induction method based on a resonant system for transmitting electricity at an increased frequency. Induction heating occurs in the metal due to the excitation of electric currents by an alternating electromagnetic field. With induction heating, only the conductive body is heated, and not the heating element. In the surface layer, called the penetration depth, 86 % of the total power is released, which saves energy. At resonance, active and reactive energy is used.

In the experiment a resonant single-wire system for transmitting electrical energy was used to power the induction heaters of the switch rail. Electrical and thermal parameters of the induction heating system were measured. Its advantages over the rail heating system with tubular electric heating elements (TEH) are considered.

Developed equipment operates according to the principle of “direct heating”, which allows to increase the heating rate or reduce electricity consumption at the same heating rate as compared to TEH. It is possible to use one power converter for several switches. Due to its higher heating temperature combined with relatively low power consumption, it is suitable for use in the northern regions.

Developed equipment is connected to AC network with a voltage of 380 V and 50 Hz, operating frequency range is 6–10 kHz, power consumption for heating a single object is 6–20 kW, and the voltage on the transmission line is less than 1 kV.

Estimation of the average time to failure of the turning steps according to the operation data

The purpose of this study is to determine the empirical law of the distribution of developments to the failure of the turning steps installed on passenger cars of locomotive traction.

The correct choice of the distribution law for each technical product allows for the current calculation of reliability indicators, predicting them, as well as developing preventive measures for a specific technical product and leveling costs both during production and during operation.

The article presents well-founded arguments that the failure time for turning steps is characterized by the Weibull distribution law. For confirmation, a statistical criterion for checking the deviation of the distribution from the normal one was applied.

On the basis of carried statistic analysis a histogram of frequencies and a line of the density function of samples of failure time in the data fixation period from 2010 to 2017 were built. Results of applying the χ2 agreement criterion in the same software environment revealed that the failure time of the closed turning step comply with the law of Weibull distribution. Authors suggest using the maximum likelihood method to identify Weibull distribution parameters, on the basis of which the value of the point estimate of the mean time to failure is calculated.

Based on the research, it is concluded that this type of distribution law and the process of finding its parameters should be introduced into the program and methodology for assessing the operational reliability of the turning steps, when calculating the average time to failure of the steps, and consider the possibility of applying this law for analogous products.

In conclusion, calculation of the pointed estimation of the average time to failure of the closed turning step was made on the basis of operational tests for one year in accordance with the adopted distribution law.

Development of the lubricant for side-mounted rail flange lubricators for traction rolling stock