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In article are considered standard technologies of ultrasonic inspection of under-hub parts of press-fitted wheelset axles accordingly to existing regulations: GD (Guidance Document) 07.09-97 and STO (Standard of the Organization) Russian Railways 1.11.002-2008, and proposed improve-ment measures of nondestructive inspection that are confirmed by calculation and experimentally

A theoretical and practical study of gondola cars equipped with various models of trucks: 18-100 and 18-9810. Compiled design scheme, system of differential equations and bringing its solution for different types of trucks. The analysis of the solutions of this system are found depending on the amplitude of the pitching and bouncing speed carriage movement. Found dynamic forces on the one spring group. Based on the comparison of the two bogies conclusions about the benefits of truck 18-9810.

Based on the analysis of the empty rolling stock on the Krasnoyarsk and East Siberian Railways, the technical parameters that have a significant impact on the unloading of the wheel of the first wheel pair in the course of movement are determined. The design features of wagons influencing the safety coefficient of train traffic are considered. Statistical processing of these gatherings, according to the materials of official investigations, revealed a number of interesting features. One of them is non-normalized total gaps in the sliders along the diagonals of the wagons. This fact in the movement of empty car causes misalignment of the body, which in turn leads to a redistribution of the loads acting on the spring kits on the sides of carts and wagons. The influence of elastic suspension parameters (height, spring break) on the redistribution of loads acting on the sides of the trolley is considered. The misalignment of the body of empty wagons, especially wagons with a sufficiently small mass of unsprung parts and a high center of gravity, leads to a significant reduction in the safety factor. The calculation of the transverse guiding forces acting at the point of contact of the wheel and rail, as well as their effect on the unloading of the wheel. It is revealed that the body skew leads to a significant increase in lateral force, which affects the stability of the empty rolling stock.

A study of the influence of non-linear parameters spring of a freight car suspension (stiffness spring, length base of a bogie, roughnesses railway) on the amplitude and phase fluctuations bouncing body is completed. Defined own vibrational frequency jumps car body as a function of the parameters.

The influence of parameters of the spring suspension of freight wagon and axial load on its dynamic qualities and traffic safety. Showing the flaws of the standard three-piece bogie, influencing the dynamics and traffic safety. Investigated the horizontal dynamics of the of freight vechicle and the value of horizontal stiffness of spring suspension bogie for unoaden vechicle .

To increase the speed of the cargo delivery, freight wagons are being developed, intended for the design speed of 140 km/h. One of the important parts of a freight wagon is the bogie, the design of which determines the wagon dynamic behaviour. The bogie of such wagons uses a frame of a rigid design, which is susceptible to antisymmetric loads. The analysis of standards has shown that the strength test during designing a rigid bogie frame under the impact of maximum antisymmetric forces that may occur in operation when a wheel derails is not required, which can lead to a residual antysymmetric deformation of the bogie frame. Theoretical research is performed to estimate the impact of the residual antisymmetric deformation on traffic safety using the wheelset safety factor against derailment. The research results have shown that the bogie frame residual deformation leads to a load redistribution on the wheelset axle journal, which, in terms of the impact on the wheelset safety factor against derailment, is similar to the wagon rolling motion. The wagon rolling motion affects the reduction of the wheelset safety factor against derailment to a greater extent than oscillations during pitching and bouncing. Thus, the permission to operate wagons with the antisymmetric residual deformation of the bogie frame without its non-destructive testing can lead to traffic safety violation. In order to ensure the traffic safety of wagons with bogies having rigid frames and reduce economic losses at the design stage, bogies strength depending on the action of antisymmetric forces should be estimated.

The purpose of the work is to assess the energy efficiency of recuperative braking of a passenger DC electric locomotive when a train is moving at an unsteady and steady speed, to determine the degree of influence of the speed of movement and electric heating of passenger cars on the return of electricity during recuperative braking of an electric locomotive, to develop recommendations for improving the energy efficiency of passenger DC electric locomotives. The following methods were used: comparative analysis, methods of traction calculations, linear regression analysis, energy balance method. The equations of the energy balance of the movement of a passenger train and its components are considered in the mode of regenerative braking, allowing to identify the main factors affecting the return of electricity. The dependences of the return of electricity during regenerative braking, allowing to evaluate the influence of the train running mode and electric heating of passenger cars on the return of electricity during regenerative braking of an electric locomotive, are obtained. Developed recommendations to reduce the energy consumption of passenger trains. The conditions under which it is possible to increase the return of electricity during regenerative braking of passenger electric locomotives are determined. The developed proposals will allow increasing the energy efficiency of passenger DC electric locomotives.

Solidifying transportation of goods by rail, namely, tank wagons is accompanied a number of difficulties. These include: lowering the temperature of the transported oil, accompanied by the growth of its viscosity, the inability to quickly discharge, change in performance of transported oil products, an increase in idle tank cars. The analysis of the cooling rate of the goods transported, depending on the size and thickness of the insulating layer. Introduced formulas show that the presence of the heat-insulating sheath is cylindrical vessel radius deviation from the optimum value. When this thermal insulation reduces considerably the heat transfer coefficient in the surrounding area and to accelerate the discharge process.

The article describes trends in the technical development of fixing devices for containers, called a "fitting retainer". Containers have gradually conquered the transportation market in the USA, Europe and Asia. And each means of transport: road, marine and railway one needed devices to fix containers, because all participants of the transportation process are responsible for the safety of goods. In the period of the appearance of container transportations, commercial agreements between operators and transport companies played an important role, influencing the unification of overall dimensions and weights of containers and transported goods, which was a prerequisite to create fittings for containers and, as a result, fitting retainers for all means of transport. The domestic regulatory framework also required updating, monitoring a large number of flat wagon manufacturers and taking into account severe operating conditions of containers throughout the entire railway network. With the rapid development of the container transportation market on long routes from China to Europe and the transition to the technology of accelerated container train sets based on high-speed flat wagons, it becomes necessary to solve the issue of wind protection of empty containers and low loaded containers, taking into account the speed of up to 140 km/h. Well-known technical solutions from different manufacturers to fix containers in retainers of special shapes and with additional fixing through a retainer hole have been analyzed. An original technical solution of the fixing device is proposed, performed in the flat wagon opposite each fitting to install the container. By turning this device using man power, each corner of the container can be fixed to prevent empty containers from falling (tippling) from flat wagons when exposed to wind loads, which meets requirements of safety, operation and reliability of fixing the container in the flat wagon.

A study of the influence of non-linear parameters spring of a freight car suspension (stiffness spring, length base of a bogie, roughnesses railway) on the amplitude and phase fluctuations bouncing body is completed. Defined own vibrational frequency jumps car body as a function of the parameters.

The used liquid wash solutions utilization problem in railway depots of Russian Federation was overviewed. Postulated, that it is important to solve ecological and energy efficiency problem together on railways. Authors shows, that in this moment level of development and using resource saving technology in railway depots is too low. Economical, juridical and technological aspect of this problem was analyzed. Shows, that in present conditions we need to treat wash solutions in the closed water recycling process. Simultaneously waste products must be concentrated and then used, taking into consideration, that concentrated waste products contains flammable oil-products. Proposed to combust it and generate heat energy. Taking review of oil-containing waste products concentration and combustion methods. Shows, that heat energy can be used for grows up energy efficiency of railway depots. Described theoretical basics, results of carried experiments, and economic effect was estimated. It`s proved, that proposed technology is useful and can be realized. Preferred construction of washing machines and waste treatment facilities are recommended. Ways of next research work are selected and proved.

Transportation in tank cars of viscous liquid cargo (fuel oil, paraffins, industrial oils, cracking residues, etc.) is difficult with their solidification, accompanied by a sharp increase in viscosity. In fact, this leads to the need to warm up or partially warm up the transported oil product before unloading, usually carried out as a gravity discharge, in order to restore the fluidity of the delivered oil cargo. The process of unloading in this case with heating leads to a significant increase in the cost of transporting petroleum products, including the downtime of tank cars, and in general, a decrease in the turnover of rolling stock. According to the analysis carried out to determine the costs of the technological process of heating frozen petroleum products transported by rail, about 600 thousand tons of conventional fuel are spent per year, and the idle time of tank cars under unloading and subsequent cleaning of boilers from high-viscosity residues of oil cargo exceeds 1 million car-hours. The urgency of the issue of reducing the cost of railway transportation of viscous cargo is due to the intensive development of the Northern and Eastern regions of the Russian Federation. Important factors for transportation in these conditions are not only the negative average daily air temperature, but also long distances. The issue of reducing the cost of transportation of viscous petroleum products at low air temperatures is considered. Viscous petroleum products, when thickened, turn into a rheological liquid, which does not have a clear interface between the liquid and solid phases. The methods of transfer to the stratified state of hot fuel oil during its slow cooling and partial solidification with the formation of a heat-insulating layer of solidified fuel oil are applied. The positive effect is achieved by reducing the time and cost of thermal energy for unloading the delivered oil product by reducing the rate of its cooling during transportation. This, in turn, is achieved by suppressing the natural convection of the hot oil product on the cold walls of the boiler of the tank car in the first few hours after filling the tank. From the comparison of the experimental data and the calculation results, the values of the empirical coefficients of the equation for the heat transfer coefficient of liquid petroleum products are selected. The standard deviation of the absolute temperature of the liquid petroleum product was 8 %.

The article deals with the issue of the formation of defects of thermomechanical origin (sliders) on the rolling surface of wagon wheels during their skidding along the rail, since such defects affect traffic safety to a greater extent. In addition, such defects on the tread surface of the wheel are difficult to eliminate in the repair industry. It is known that the slider is formed when the wheel is jammed and its translational movement (sliding) along the rail, the so-called skid. As a result, in the area of contact between the wheel and the rail, intensive wear of the wheel material is observed, as a softer element, and a wear area (slider) is formed. The slider is evaluated by such a parameter as the depth relative to the wheel tread. An algorithm for calculating the depth of the slider is given under the condition of a short-term movement of the wheel along the rail skidding. The initial data were determined and a calculation was made with the construction of graphs that reflect the dependence of the slider depth on the speed of the rolling stock and the load on the axle of the wheelset during short-term skidding. A technique for calculating the maximum temperatures in a pair of sliding friction "wheel-rail" is described. The values of the maximum temperatures in the contact patch are calculated when the wheel moves along the rail skidding. Based on the results of the calculations, graphs of changes in the maximum temperatures on the wheel tread surface in the area of friction on the rail under various operating conditions were plotted. An assessment is made of the possibility of indirect determination of the depth of the hardened metal layer in the area of the slider, depending on its dimensions, measured when the wheelset was received for repair.

In the article the comparative analysis of the dynamic loading of the floor of the car with different types of trucks in various modes of movement (loaded, empty). Commissioning of the new trucks is due to an increase in accidents in the operation of a gondola carts 18-100.

The article solves the problem of optimal selection of rolling stock within groups according to the criterion of minimum sum of squared deviations of the current values of a given metric on the evaluation of their mathematical expectations for group objects. The solution obtained on the basis of methods based on ideas integer programming using Boolean variables and concepts of the relation between objects and between groups of objects.

The analysis of the development of the wheels increased hardness on the example of certain manufacturers, and changing regulatory and technical documentation for production (GOST). A mathematical analysis of the comparison operation wheelsets normal hardness of the wheel pairs of high hardness, based on the receipt of freight wagons from production to unscheduled maintenance. For comparison methods were used: Cramer - Welch and Laplace function. The estimation of av-erage mileage of cars on different types of wheel sets of freight cars and production technology. Developed the basic advantages of high hardness wheelsets.

The method of determining the costs of technological time of processing trains en route has been improved, taking into account the duration of all operations performed by wagons at stations for the effective organization of freight transportation technology on railway transport. A model for calculating the delivery time of goods has been developed to correctly determine the time spent by loaded wagons en route. A method has been developed for determining the time spent on technological operations at stations and the delivery time of goods. The developed method allows you to determine and plan in advance the amount of work that will be performed at the stations. The indicators affecting the duration of the time of delivery of the cargo are given. An improved formula for determining the delivery time of goods by rail is recommended. The article proposes a technology for calculating the daily mileage rate of wagon shipments, depending on the technological operations performed with wagons at stations and the distance of transportation. The reliability of the research results is confirmed by the use of modern calculation methods. Theoretical studies were conducted on the basis of the laws of mathematical statistics. The scientific significance of the results obtained is characterized by the improvement of methods for determining the costs of the technological time of processing trains and the timing of cargo delivery based on the systematization of conditionally constant and random factors affecting the transportation process on railway transport.

The article presents the results of research of a point magneto-induction sensor based on a mathematical model, which allows you to increase the reliability of automated systems for diagnosing technical condition rolling stock in the course of train movement by improvement the accuracy of the initial information, that is, the moments of fixation passing of wheelset axles over magneto-induction sensors. At the first stage of developing a stigmatic mathematical model the analytical dependence of the value of the magnetic flux in the magnetic core and the output EMF value on resistance of the air gap between the sensor and the wheel crest. At the second stage of development of the mathematical model found time dependence of the magnetic resistance of the air gap between the core of the magneto-induction sensor and the comb wheels of a railway car moving along a straight track at a constant speed. On the basis of application the developed stigmatic model allows evaluating the energy parameters of magneto-induction sensors depending on the properties of modern magnetic materials. The simulation results showed that the MMF value is constant the magnet determines the main parameters of magneto-induction sensors, so the use of modern magnets based on rare earth they allow to eliminate the traditional disadvantage of outdated types of magneto-induction sensors, that is, to reduce their size and weight. The application of the proposed stigmatic model expands the scope of possible solutions to extreme problems for selection and justification parameters of magneto-induction sensors, helps to improve the accuracy of systems for diagnosing the technical condition of the car fleet and traffic safety on railway transport.