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Scientific and technical journal established by OSTU. Media registration number: ПИ № ФС77-75780 dated May 23, 2019. ISSN: 2220-4245. Subscription index in the online catalog «Subscription Press» (www.akc.ru): E28002. Subscription to the electronic version is available on the «Rucont» platform.
The journal is included in the Russian Science Citation Index and in the List of Russian Scientific Journals .

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  • V.4(48), 2021
    2-11

    Research of the forces acting on the latch of the vacuum switch vbo-25-20/630 uhl1

    The experience gained in the operation of high-voltage vacuum circuit breakers VBO-25-20/ 630UHL1 indicates an incorrect assessment of the mechanical resource of its individual components and elements. Despite the repeated improvement of the design of the main switch drive, applicable both as part of the new «Ermak» series locomotives starting from number 1000 series, and in earlier numbers, the dynamics of malfunctions continues to persist to the present time. One of the most important elements of the main switch is a latch designed to hold the elements of the drive mechanism in the on position, the failure of the latch entails the failure of the entire section of the locomotive. The article considers three latch upgrades previously proposed by the manufacturer, a kinematic scheme of the drive with a vacuum arc-extinguishing chamber of the switch is developed, the parameters of the preload and trip springs in the drive are calculated, the forces operating during operation are determined. On the example of the latest modernization of the latch using the finite element method in the SolidWorks Simulation software package, a strength calculation was carried out, according to the results of which the stresses arising in its design were determined. As a result of the analysis of the finite element model, the forces critical for the structure are determined, a graph of the dependence of the structural strength margin and the maximum stress in the structure on the acting forces is developed. According to the results of the study, the force at which the most favorable value of the safety factor is provided is determined, for which it is proposed to reduce the critical force by changing the parameters of the compression springs and disconnecting the drive of the arc extinguishing chamber. A loading diagram with the drawing dimensions of two modified springs has been developed.
  • V.2(22), 2015
    2-6

    State question reliability and durability insulation induction auxiliary machines

    This article presents an analysis of the reliability of asynchronous auxiliary machines (AAM) type NVA-55 electric locomotives «Ermak» in custody Art. Vihorevka (East-Siberian Railway) and Art. Smolyaninovo (Far Eastern) for the 2009-2011 year. Identified the weakest in terms of reliability components and analyzes the main types and causes of these types of faults AAM. One of the research objectives reliability AAM type NVA-55 is to determine the mean time between failures that could prevent failures in the organization of maintenance and repair, as well as extend the life of the machine. Defining the objective mathematical expectation of failure AAM for effective correcting the overhaul life mileage is not possible, since failures are largely have random and not permanent.
  • V.4(44), 2020
    2-8

    The probability calculating of failure categories of the locomotive equipment reliability

    The article discusses the specifics of the locomotive reliability indicators use in the Russian Railways. Examples of locomotive reliability indicators and the indicators used in the Russian Railways in the conclusion of service contracts, including under the life cycle contract are given. A method of transition from national standard to Russian Railways has been proposed. It is concluded that these procedures can be automated.
  • V.1(41), 2020
    20-29

    Design of industrial installation for strengthening polymer insulation of magnetic system of electric truck motor by heat radiation

    Constantly conducted studies of the reliability of electric equipment of traction rolling stock have shown that the most vulnerable element is the insulation design of the windings of power equipment, especially traction motors. Existing methods and means of restoration and repair of insulating structures of windings of traction motors of modern electric locomotives, based on drying polymer insulation in convective high-power electric furnaces, are energy and time-consuming. This technology has not undergone significant changes for over 50 years. In order to extend the polymer insulation life of electric vehicles of traction rolling stock, an insulation drying technology using thermal radiation was proposed that reduces the cost of electricity for repairs and increases the drying speed by reducing heat loss. The article is devoted to the design of a new device for drying the insulation of the windings of the magnetic system of the skeleton of the backbone of the electric locomotive traction engine by a rotating thermal field. The analysis of works and conclusions based on the results of theoretical studies related to mathematical modeling is presented. As a method of mathematical modeling, the finite element method was used in the work. A simplified 3D model of the winding of the core magnetic system with infrared emitters was created. According to the results of finite element mathematical modeling, temperature fields of heating the polymer insulation of the windings of the core of the traction motor were obtained. Based on this calculation, the work selected the optimal design parameters of the proposed device that provide the minimum energy costs for various sizes of the skeleton of the traction engines. Based on the proposed device variant, an application for a patent for a utility model has been filed, and this prototype is being assembled on the basis of the Ulan-Ude locomotive and car repair plant, a branch of Zheldorremmash JSC. New directions for further research are also set.
  • V.3(43), 2020
    20-27

    Multi-factor analysis of statistical information using fuzzy set theory techniques

    The article proposes a method of using the mathematical apparatus of the theory of fuzzy sets in automation of the locomotives reliability management, because when writing algorithms there is a problem of transition from not fully formalized concepts of human communication to formalizing software. Examples of the fuzzy sets use in calculating the locomotives reliability are described. When calculating the reliability parameters manually, the volume of calculations does not allow you to move to more complex algorithms. When there are automated systems, it is necessary for each indicator of the transportation process, which affects its reliability, to set the function of belonging to a dangerous and normal value using the mathematical apparatus of the theory of fuzzy sets. Then the risk of a dangerous event will be assessed in probability, taking into account the logical claim to the risk.
  • V.3(23), 2015
    24-31

    Fuzzy set in decision support system of locomotive complex information systems

    The article proposes the use of Fuzzy Sets theory in decision-making support system of locomotive complex IT-control systems. For this purpose the method of translation linguistic assertions into the language of mathematical logic proposed, which will be introduced on a built-in quality in the IT-control system of monitoring of technical condition and modes of operation of locomotives service company «TMH-Service» and management company «Locomotive technologies».
  • V.1(17), 2014
    26-30

    Basis of local life extension method insulation of electric machines of locomotives thermal radiation

    The main damaged knot of traction electric motors of a traction rolling stock is isolation, namely in the field of the basis of front part. The imperfect system of isolation in face part of front windings results in humidity. Also the increased intensity in this zone is the reason of low reliability. Authors propose the system of local insulation encapsulation energy of infrared radiation as life extension activities of electrical machines.
  • V.4(24), 2015
    27-33

    Performance features asynchronous electric locomotive auxiliary machines ac on east siberian line

    This article analyzes the conditions of work of asynchronous auxiliary machines (AVM) electric AC, mainly operated on the network of the East-Siberian railway. Presented the experimental data on the dependence of the motor phase currents ANE 225 locomotive VL 85 on the value of the supply voltage, the duration of start - MC with an induction motor, depending on the voltage of contact network, change the moment of resistance of the compressor depending on the air temperature. Reviewed the features work of the AVM, in particular, their alternate launch of its own needs winding of traction transformer. As a result of systematization of operating conditions affecting the isolation of AVM in order to optimize the parameter tracking their rate of wear, which resulted in the allocated two major factors of aging insulation overheating and vibration, and one factor that increases the probability of failure, regardless of the degree of aging of insulation - it moisturized
  • V.2(34), 2018
    29-35

    Assesment of observed reliability measuresof locomotive equipments

    One of the main tasks of optimizing the periodicity of maintenance operation and repairs is to obtain an economic effect with the preservation of high reliability of rolling stock equipment. To obtain an economic effect, it is necessary to conduct an investigation all possible factors affecting the operation of rolling stock under specific operating conditions. Their influence has a direct impact on the reliability of rolling stock.
  • V.3(51), 2022
    35-43

    Optimization of standards of repair runs in locomotives series 2(3,4)es5k on the basis of failures of the traction motor

    System of preventive maintenance and maintenance of the operable condition of the traction rolling stock. The subject of a global study of failures of traction motors in the event of a breakdown on the territory of the service locomotive depot «Dalnevostochnoye» and «Primorskoye» for 2019. The purpose of the study is to determine the possible norms of overhaul runs for the considered node in order to achieve the optimal number of locomotive calls for unscheduled repairs. In the work, the correct law of distribution of traction motor (TED) failures, the determination of the Sturgess, Pearson coefficients and other methods of mathematical statistics and the theory of justification of systems. The article defines an element that limits the norms of overhaul runs of traction motors; the theoretical distribution of traction motor failures due to a decrease in the insulation resistance of its windings has been obtained. As part of the study, the optimization of the norms of overhaul runs was carried out according to the conditions for conducting maintenance regarding the traction motor. As a result of the analysis of the causes of failures, it was found that more cases of placing locomotives for unscheduled repairs occur in the first mileage interval of locomotives due to poor quality diagnostics at TR-1 upon measuring the resistance of the insulation windings. Most of the failures occurring in the first period of operation are not associated with a change in the reliability of the considered node. When considering two normal peaks of failures, falling on the operating time intervals 14-21 and 28-35, the necessity of optimizing the norms of overhaul runs is determined. When considering two normal peaks of failures, falling on the operating time intervals 14-21 and 28-35, the necessity of optimizing the norms of overhaul runs is determined. The practical significance of the study lies in the possibility of using the option of optimizing the norms of overhaul runs to adjust the norms of maintenance and repair periods within specific depots.
  • V.4(52), 2022
    41-48

    Investigation of reliability and improvement of the efficiency of the hydrostatic fan drive of the diesel locomotive cooling system

    The design of the hydrostatic fan drive of the cooling system of diesel engines of passenger locomotives of the TEP70 all series is considered. According to the results of the analysis of malfunctions of components and parts of the cooling system of locomotives, it showed that the main reasons for the failure of the hydrostatic fan drive are: the destruction of the housing and overheating of the bearings of the hydraulic motor, oil leakage at the installation site of the rubber diaphragm and loss of rigidity of the spring of the thermostat. The reasons for which are often the temperature conditions and the life of the parts. The article discusses the issues of improving the efficiency of the hydrostatic fan drive of the cooling system of diesel locomotives. An increase in the life of the hydraulic motor can be achieved by eliminating idle from its operating time, since it is connected by a rigid coupling with the diesel shafts. Ensuring the independence of the operation of the hydraulic motor relative to the diesel engine is possible by changing the design of the hydraulic fan drive, by installing a viscous coupling for the transfer torque of the shaft only during the period of necessary useful work, when a certain oil temperature is reached. To increase the reliability of the thermostat, the possibility of installing an additional rubber diaphragm with increased tension force, for trouble-free operation of the thermostat when the pressure reaches 12 MPa and when the oil viscosity decreases, is considered. A malfunction of the thermostat often leads to the most serious consequences, up to the failure of the locomotive, where the most common cause is the loss of rigidity of the spring of the thermostat due to the jamming of the spool, which affects the redirection of the oil flow, and there is a high probability of an increase in the temperature of oil or water in the system. The considered main malfunctions of the hydraulic fan drive and ways to solve them will significantly increase the reliability of its operation and the efficiency of passenger locomotives.
  • V.4(36), 2018
    41-53

    Locomotive operating efficiency study

    Principal directions for increase of locomotive operating efficiency are determined in the article based on statistical estimates as per data on the main domestic locomotive series. Work ratio is suggested as universal indicator. It is demonstrated that in addition to locomotives' reliability enhancement, increase of the trains' haulage management system efficiency is also a large reserve. It is proven that the number of locomotive units can be reduced at least by 2,000 thous. units.
  • V.2(42), 2020
    44-52

    Defects recognition of axle caps of the rolling stock wheel-motor block based on the results of modeling an artificial neural network for predicting output diagnostic parameters

    The article presents the results of the research conducted by the authors, the purpose of which was to development a model for recognizing defects in axle caps of a wheel-motor block of a locomotive in order to implement automatic advance notification of management structures about the need for maintenance or repair operations to eliminate defects at an early stage of their occurrence. The research used the following interdisciplinary and mathematical methods: computer and mathematical modeling, methods of mathematical statistics, methods of the theory of artificial intelligence and parametric reliability. As a result of the research, a mathematical formalization of the model for recognizing one of the defects in the axle caps of the wheel-motor block of the locomotive - the groove (chipping) of the babbitt layer was obtained. With the help of the obtained model, it is possible to implement automatic recognition of defects, pre-failure states not only of axle caps, but also of other units of technical systems. The developed model can be used in monitoring systems, control, diagnostics of the technical condition of the locomotive fleet, in order to reduce downtime in repairs and forced costs for scheduled operations. The proposed model solves the range of problems described in the development concept of JSCo Russian Railways associated with the implementation of the actual repair system for the current technical condition of the locomotive, as well as with the digitalization of the company's advanced areas.
  • V.4(40), 2019
    54-61

    Determination of rational terms for rehabilitation of electric locomotive equipments

    The article is devoted to the definition of rational overhaul runs equipment of locomotives. This has an impact not only on the reliability of the rolling stock, but also on safety. As a method chosen for the implementation of this task, the functions of the failure rate are used, with the subsequent construction of the functions of resource distribution and determining 90 % of the resource of the equipment of electric locomotives. The proposed technique allows you to determine the rational timing of maintenance and repair of locomotives in the specific conditions of their operation. The calculations are based on information about changes in the technical condition of the wheel-motor block of VL10 electric locomotives.
  • V.2(50), 2022
    66-73

    Mathematical methods for reliability verification of data on reliability of locomotives, their operation and maintenance

    In the practice of railway transport and the locomotive complex, the average statistical data used in practice are not homogeneous, which is usually called “average temperature in the hospital” in the literature. The homogeneity of data is determined by their unimodality, i.e. the presence of one process in the sample. Unsuccessful sampling leads to its bimodality and even multimodality. It is proposed to check for unimodality of the initial data using the consequence of the law of large numbers, according to which, with an increase in the number of data, homogeneous samples tend to one of the distribution laws of a random variable: normal, exponential, lognormal, or another known law. Therefore, any unimodal sample must meet the goodness-of-fit test, which the article proposes to use the Pearson test (“chi-square”, χ2). The unimodality of the data is proposed to be estimated through the probability of compliance with the law of distribution of a random variable chosen for consideration, considering the probability of more than 0.3 (30%) to be sufficient. On the example of locomotive operation data and on-board microprocessor systems data, data are shown that cannot really be unimodal, but there is data that requires changing the sampling rules to achieve unimodality. For example, when considering the average daily runs of locomotives by series at specific home depots with participation in one type of traffic (main traffic, shunting or switching work), unimodality is achieved. An attempt to enlarge the data (take several series, several polygons, etc.) leads to the loss of unimodality. The article considers the unimodality of these on-board microprocessor control systems MSU-TP for diesel locomotives of the 2TE116U series. The expected operating time for the positions of the driver's controller turned out to be multimodal data. Unexpectedly, the current of the traction motors turned out to be unimodal, regardless of the driving position of the driver's controller.
  • V.3(27), 2016
    66-76

    Development electrooven alloy smelting technology vanadium steel rail

    The questions of the composition of the design and technology of smelting, casting and heat treatment of alloyed rail steels having high operational stability. Together specialists EVRAZ ZSMK Novokuznetsk and IrGUPS was proposed complex doping scheme of the rail steel and rail rolling floor EVRAZ ZSMK was conducted testing of the technology of smelting and eletropechnoy thermostrengthening superperlitnoy steel of high purity, which has high wear resistance. several experimental batches were produced rails, which are tested on the site of the saddle-point Irkutsk-Slyudyanka VSZHD with an unfavorable combination of operational loads, causing increased wear of the rails. The test results showed high wear resistance experienced rails and expediency of development of industrial production.
  • V.3(47), 2021
    69-77

    Determination of durability indicators of wheelset elements based on information on the distribution of the controlled parameter of diesel locomotives of the 2te25km series

    The method of determining the durability indicators of wheel pairs of locomotives is considered on the example of diesel locomotives of the 2TE25KM series operated on the Volga railway. For this purpose, the 90% resource of the wheel pairs of the studied series of locomotives was determined, and it was compared with the accepted standard indicator. In addition, a controlled parameter of the wheelset is selected, limiting the reliability of this node. To conduct the study, methods of mathematical statistics and probability theory were used, in particular, the Laplace distribution function, the Student's criterion, as well as the results of calculations of the dependencies of the mean value and the standard deviation of the controlled parameters, the initial values of developments and operating time corresponding to the probability of failure 0.5. In this study, a mathematical model for assessing the durability of wheelsets from the point of view of reliability theory was developed. The evaluation of the durability indicators of the wheelset elements was carried out on the basis of the type of random variable distribution law with its parameters obtained on a computer and adopted according to the Pearson criterion. As a result of the calculations, 90% of the life of the wheelset was obtained according to two controlled parameters, which amounted to 476.6 thousand km for the thickness of the bandage, and 282.6 thousand km for the thickness of the ridge. The results obtained were compared with the values adopted in the Technical Specifications for this series of locomotives (800 thousand km). km), as well as with statistical data on the values of controlled parameters obtained during processing and analysis - 240 thousand km. Due to the fact that in operation the average life of the wheelset is determined by a larger number of controlled parameters, taking into account unscheduled repairs, and in this study - only on the basis of the thickness of the bandage and the ridge, it is not possible to talk about full compliance with the calculated and actual data. According to the results of calculations, the limiting reliability of the wheelset is such a controlled parameter as the thickness of the ridge. For a more accurate assessment of the durability of wheelsets, it should also be taken into account that the intensity of wear of rolling stock equipment is affected by specific operating conditions, in this regard, inter-repair runs should be adjusted taking into account the influence of external factors during operation. In order to fully assess the durability of wheelsets in the future, it is necessary to take into account additional factors, in addition to those that affect the parametric change of random variables, as well as the fact that takes into account the monitoring and analysis of all controlled parameters of this node during the operation of locomotives.
  • V.4(20), 2014
    72-79

    The analysis of the factors defining reliability of locomotives at various stages lifes cycle

    In article from positions of uniform life cycle locomotives, from creation before write-off, the major factors influencing the level of their reliability are considered. Value of these factors will give the chance to connect mathematical model the potential level of reliability put in the specification on design of new locomotives with the actual reliability in specific conditions of operation and on this basis to determine the optimum parameters systems of maintenance and repair corresponding to maximum efficiency of use locomotives for all life cycle.
  • V.4(52), 2022
    75-82

    Improvement the design and technology of repair the diesel locomotives traction electric motors

    The subject of consideration of this article is the traction electric motor of a diesel locomotive. Traction electric motor (TED) is the main element of power transmission, therefore, the reliability of the locomotive as a whole depends on its reliability. The main causes of failures of traction motors in operation are considered. Based on the analysis of statistical data, it can be argued that the most damaged part of the traction motor is its armature. In the context of the introduction of new classes of insulation heat resistance by the new standard - GOST 2582-2013 - ensuring the reliability of the anchor is especially important. The causes of the most common failures of TED in operation have been established: violation of the integrity of the insulation of the winding by the sharp edges of the extreme sheets of the anchor core iron package when laying the winding in the grooves of the core, vibration of the extreme sheets of the anchor core iron package when exposed to electromagnetic forces with a frequency multiple of the number of poles of the electric motor, imperfection of the fastening system of the frontal parts of the armature winding, mismatch of the coefficients of temperature linear elongations copper windings, insulating materials and steel core of the armature. The result of the analysis of the design of serial TED were proposals to improve the design of the nodes most prone to failures. To eliminate breaks in the insulation of anchors in operation, a new design of pressure washers and an improved technology for impregnating anchors of commercially produced traction electric motors of locomotives are proposed. The proposed design solutions can be used both when creating new TED designs for promising locomotives and when upgrading serial designs. Thus, the application of the proposed design and technological solutions will increase the reliability of the diesel locomotives.
  • V.3(23), 2015
    79-85

    The diaognostics of traction substations power rectifiers converters

    Various converters are operated at electric railways traction substations whose rectifiers design includes plug-in power rectifiers and pill ones. Such a variety of rectifiers design causes the problem of the power supply reliable operation unavailability both of volumes and of quality information concerning the characteristics and diagnostic parameters of power semiconductors rectifiers. For a possible prediction of the diodes and thyristors proper operation, new instruments as well as simple technologies of the preventive diagnostics, correspondent to the state and industry standards and instructions should be developed. One of the most accurate methods to determine not only the serviceability of rectifiers but also to forecast their wear - life, is the diagnostic method of recurrent peak backward current. This method is the basis for the design of a peak backward current meter which is used on the Western-Siberian railway. Using this device the screening of about thirty thousand rectifiers was carried out which resulted in the sorting of out-of-work rectifiers, predicting long term rectifiers conditions. The statistical analysis of the research allowed to determine the number of measures to improve the reliability of traction substations converters.
  • V.1(41), 2020
    83-91

    Improving the design concepts of equipment for the assembly platform of a rail service car considering reliability rates and real state

    The factors affecting the operational reliability of the assembly platform of a rail service car maintaining the repair and installation on the railways are considered in the paper. An assessment and analysis of a system of quantitative indices of reliability is performed, the methods for their separate determination by mechanical equipment and hydro and electrical equipment is described. The strategy of maintenance and repair combined with the use of methods and means of a modern diagnostic system is considered; it ensures the estimation of the object reliability during its design, operation and repair.
  • V.3(31), 2017
    85-95

    Determination of spare parts and materials in repair of locomotives with registration of incidentally appearing faults

    The problems of optimization of organization of maintenance and repair of locomotives. The article presents new approaches for calculating the norms of spare parts and materials. Models of vehicle systems consisting of a fleet of operated locomotives are given, taking into account all conditions.
  • V.1(21), 2015
    95-102

    Building simulation model the required quality parameters at rail grinding

    It is considered how reliability of the grinding technology influences on the quality parameters of the treated surface. The results of analysis of relationship between quality of the rails grinding and conditions of its treatment are represented. Factors affecting on reliability of the technology are reviewed also. The model determining the reliability of the rails grinding technology in the railway is represented. Also the algorithm of calculation of the grinding technology reliability is represented. It’s reviewed how the quality parameters are formed during the rails grinding.
  • V.1(45), 2021
    95-104

    On the issue of improving the reliability and durability of traction electric motors of diesel locomotives

    At this time the traction electric motor (TEM) is one of the most important elements of the design of rolling stock, since the safety and stability of the transportation process on the railway network of JSC "Russian Railways" depends on its uninterrupted operation. This article is given a detailed analysis of the TEM failures of diesel locomotives of the 2,3TE10 v / series and the assigned fleet of the Novaya Chara locomotive depot of the East Siberian Traction Directorate. The section of circulation of diesel locomotives from Taksimo station to Hani station is one of the most difficult not only in the borders The East Siberian Railway, but also the entire railway network of the country. The analysis of the statistics of the reasons for the failures of the TEM of locomotives of the Novaya Chara locomotive depot for 2006 - 2012 showed that there is a rather extreme operation mode and that most of the failures are due to the breakdown of the insulation of the anchor winding of the TEM. During a research trip to the diesel locomotive maintenance site, a team of IRGUPSA scientists conducted full-scale measurements speed of movement, driving mode of the train, heating temperature of the TEM, taken into account the climate factors - ambient temperature, relative humidity, pressure and others. After studying the available information, it was proposed to additionally coat the insulation with FL-98 varnish in order to maintain and restore its properties in the conditions of the Winter locomotive depot during TR-3. IRGUPS has been working for a long time to study the process of drying insulation using infrared radiation (IR). The effectiveness of this method has been proven by numerous experimental studies. Several PhD theses have already been defended in various dissertation councils on this topic. This article presents also the statistics of failures of operated TEM already with additional varnish-impregnated insulation of open frontal parts after the implementation of measures based on the results of the work of the IRGUPS group of scientists. It is established that the method of applying the compound to the insulation of the frontal part of the windings of electric machines and encapsulating it with the help of IR radiation energy is effective in combating TEM failures due to insulation breakdown.
  • V.1(25), 2016
    96-104

    Minimization of risk when determining the duration of liner-tamping-straightening machines

    The authors propose a model of justification of the duration of the operation liner-tamping-straightening and construction machinery. Using this model, we can evaluate the efficiency and reliability of machines on any object. This allows you to most reliably predict the timing of production of certain types of works and their cost at the design stage. The article presents the indicators of full-scale tests and the estimation of reliability of manufacturing operations. One of the main factors of reliability of work of construction machines is the utilization of their time. All normative documents are obsolete data on the utilization of machines during the working time, which need updating, as the machines are constantly improving. To assess the reliability of working machines, the authors developed a database of the results of field tests liner-tamping-straightening machines, cranes, excavators, bulldozers, pipe layers, drilling rigs and dredges. To prove the validity of database values according to the results of full-scale tests were carried out two stages of verification: logical and mathematical. After sampling in accordance with GOST R 8.736-2011 was verified that it belongs to the law of normal distribution using the criterion of Pearson agreement. It was further calculated the reliability and risk of the planned volume of work in scheduled period of time. When it was considered the utilization ratio of machines time and the risk of deviation from the mean. The proposed approach to the assessment of duration of liner-tamping-straightening and construction machinery can be extended to any type of equipment and will allow to obtain numerical values for evaluating the reliability of production work in the scheduled time, which is very important in the construction, repair and maintenance.