Using of software systems in the design of new samples is increasingly important, but there is a problem in adapting computer models to obtain adequate results of calculations. The modern development of the IT systems gives the opportunity to significantly reduce the timing of the introduction of new equipment into production by reducing the number of field experimental test samples of the design technology. Every year using of complexes software in designing new samples is becoming increasingly important, but there is a problem in adapting computer models to obtain adequate results of calculations. UM Universal Mechanism complex was used to simulate the dynamic loading process of the boot node. Modelling of dynamic loadings on the running gears of freight cars showed a sufficient convergence with the results of running tests, about 87%. Therefore, the proposed model can be used for assessing of disturbing loads when the calculating of the reliability of the bucket units of freight cars was done.

The cars that are operated on the railways of Ukraine are equipped with axle boxes with cylindrical roller bearings. Many years of operating experience has shown that they have insufficient durability. One of the reasons is the uneven distribution of the load between the rollers in the bearings, caused by the design features of the wagon bogies. One of the possible ways to equalize the distribution of loads between the rolling elements can be the creation of a box housing with variable stiffness. The article provides a detailed analysis of existing design solutions. It has been established that the use of aluminum alloys for the manufacture of axle box housings, despite the low specific density of the alloy, is impractical due to their high cost, increased wear of the bearing surfaces, and insufficient service life. The use of rubber as gaskets to create variable stiffness also proved to be impractical. The reason is the inability of rubber to operate at low temperatures in winter. As a result, the destruction of the rubber required additional (unscheduled) axle box repairs. The manufacture of axle box bodies with cavities or grooves of various configurations in order to change the rigidity of the elements of the upper part of the axle box body turned out to be unpromising. The reason was the technological complexity of manufacturing, the difficulty of providing the necessary strength under dynamic loading conditions. The most successful was the design of the box body with two rectangular tides along the edges of the upper part in the roller loading zone. These lugs are located along the entire length of the hull and are the supporting surfaces for transferring the load from the side frame. A promising direction in the 70s of the XX century was the rejection of traditional massive axle boxes and the transition to the use of adapters (half axle boxes). However, this option had to be abandoned at that time due to the impossibility of ensuring reliable sealing of the bearings. At the same time, the modern experience of American railways shows that one of the promising areas for improving the design of roller axle boxes is the use of adapters in freight bogies of wheelsets equipped with cassette bearings. The adapter redistributes the load from the bogie to the cassette bearing, acts as a supporting part of a conventional axle box and limits the longitudinal, transverse and angular shifts of the wheel set relative to the bogie frame. In addition, the adapter allows you to reduce the tare weight of the car. However, the use of adapters is possible only if the bearings themselves are reliably sealed. Also, a promising direction can be considered the creation of a box body with variable stiffness, including the use of rubber-metal elements. Keywords: freight car, axle box, housing, bearing, adapter, support surface, actuation.

The article is devoted to the analysis of the level of safety on Ukrainian railways. The reliability of wagons plays an important role in ensuring safety. Uncoupling of wagons along the route due to failures of wagon structural elements causes transport incidents and can lead to an emergency. The most common reason for uncoupling a wagon from a train is axle box failures. The conducted studies show that the absolute number of uncouplings of wagons along the route has decreased compared to 1995. But the number of uncouplings caused by roller axle box failures remains at a high level with certain fluctuations. Functional dependences characterizing the change in the number of cuts over time are determined. For a more complete description of the change in the level of traffic safety on the railways, the performance indicators were considered depending on the overall performance of the railway transport. In particular, the number of working park was taken into account. It has been established that over the past decade, in relation to the working fleet, the number of wagon failures due to the fault of roller axle boxes remains practically at the same level. An analysis of the causes of failures shows that the main one is damage to cylindrical roller bearings. This is followed by end mount failures. Attention is drawn to the sharp increase in the number of failures caused by non-compliance with the technology of installation work. This indicates insufficient qualification of the service personnel. Lubricants for bearings have insufficient reliability. Also, a number of failures are caused by damage to the axle boxes. The lack of reliable methods for diagnosing axle boxes failures at an early stage in operation leads to the occurrence of fractures of the axle journals. One of the possible ways to increase the reliability of axle box units is the use of cassette bearings, which have a number of significant advantages.

The authors determined the intensity of the increase in wear of various elements of the body. It has been established that the lower trim, the roof slope and the lower part of the side wall have the greatest wear. It is proposed to use aluminum alloys for the modernization of passenger car bodies. The advantage of such a technical solution is an increase in the corrosion resistance of the body. The reduction of tare allows to reduce the specific resistance to train movement, reduce fuel and electricity costs for train traction. To reduce operating costs using the basic provisions of the locomotive traction theory, calculations were made to determine the energy consumption for the movement of a passenger train according to the profile conditions of the real section of the regional branch of the Southern Railway by diesel and electric locomotive traction with the base variant and the variant of passenger cars with reduced tare weight) in composition of the train. It has been established that the annual savings in energy costs for the traction of passenger trains when using passenger cars with a reduced tare weight is about 1 million UAH.

The efficiency of passenger transportation by rail depends on the level of technical condition of the passenger rolling stock. The repair and maintenance system is also important. The authors analyzed the technological states of a passenger car can during operation. It is shown that the time spent in these states and the set of technological operations that are performed at the same time do not fully reflect the relationship between the resources consumed for their implementation, the operating costs of these resources and the results. The article presents the results of systematization of the technological states of passenger cars. At the same time, the procedure for accounting for operating costs for the main types of economic activity of Ukrainian railway transport was used. A system of technical and economic indicators is proposed. It characterizes the availability and efficiency of the use of operating costs for the operation and maintenance of passenger cars in a technically sound condition. The concept of "economic and technological state of a passenger car" is substantiated. The systematization made it possible to combine, on a scientific basis, the technological and economic aspects of the operation and maintenance of passenger cars in a technically sound condition in the conditions of JSC "Ukrzaliznytsia". This will improve the system of indicators for the technical and economic evaluation of the effectiveness of the use of existing passenger cars. The proposed system will be used to justify options for updating the fleet of passenger cars through the acquisition of new models or the modernization of existing ones, taking into account the cost of the life cycle.