In widespread sources the results of calculations of the sizes of contact planes of anellipse form at interaction of locomotive wheels with rails of type P65 which small axes make 5-10mm depending on loading taking into account dynamic influence are resulted. These data do notcorrespond to the purpose and objectives of this study, which is to determine the size of the half-axisof the contact plane under vertical load on the head of the rail thread in the range from 100 kN to180 kN, when the wheel of the freight car rests on a bevel a wheel having a conicity of 1:10, with awheel radius r1 = 475 mm and a rolling surface radius of the rail head r2 = 80 mm. The size of thecontact plane of support of the rim of the wheel of a freight car on the surface of the head of the railtype P65 is determined in the work. The calculations were performed on the basis of preliminarydetermination of the location of the mathematical point of contact on the box curve, which outlinesthe surface of the rail head in cross section under deterministic conditions of pressing intermediaterail fasteners of separate type under the action of outstanding accelerations for freight -0.3 m / s2.The purpose of the calculations is to obtain the practical value of the maximum dangerous width ofthe rail track, which corresponds to the conditions of track expansion at vertical wheel load on therail 140 kN and at maximum spacing forces that provide the highest values of lateral displacementsrail thread with a surface adjacent to the chamfer of the wheel rim. Based on calculations by the Hertz-Bilyaev method, it was obtained that the average value of the contact strip of the rail and therim of the wheel of a freight car, at a vertical load P = 140 kN, is: b = 3.2 mm, so b / 2 = 1.6 mm.But if you round to the accuracy of measuring the width of the rail track - b / 2 = 1.6 mm.

The introduction of high-speed traffic in the railways of Ukraine is one of the priorityareas of development of the domestic railway industry. Foreign experience in the operation of highspeed and high-speed lines has a positive impact on the overall economic performance of thesecountries by increasing the mobility of means of production and human resources. In addition,increasing speeds requires the introduction of new types of rolling stock and railway structures withunconditional provision of the required level of safety. This is possible only through a comprehensiveapproach to these issues, both through experimental tests and theoretical calculations. This studytheoretically assessed the possibility of operating intermediate rail fasteners type KPP-5 Ukrainianproduction in areas where in the medium term, it is planned to increase speeds, i.e. to reach a levelof more than 160 km/h. To achieve this goal, multivariate calculations were performed to determinethe stress state that penetrates the elements of the railway track under the action of rolling stock.Four types of high-speed locomotives and electric trains, which have been operated on the railwaylines of the European Union for a long time, were selected as units of account in the study. For alltypes of rolling stock (locomotives and high-speed electric trains) for which calculations wereperformed, the obtained values of stresses acting in the elements of the railway track do not exceedthe allowable. That is, in terms of strength, intermediate rail fasteners type KPP-5 Ukrainianproduction can be operated in straight sections at speeds over 160 km / h with heat-treated rails typeR65 on reinforced concrete sleepers with laying diagram 1840 pcs / km with gravel ballast 40 cmthick. Analytical comparison of the level of stresses arising in the railway track elements in lines withintermediate rail fastening type KPP-5 made in Ukraine and the W30 rail fastening systemmanufactured by Vossloh showed approximately the same level of stress in the railway track elements.However, it should be noted that the above conclusions are only theoretical in nature and for thefinal determination of the possibility of operation of the intermediate rail fastening type KPP-5 inreal conditions (at speeds greater than 160 km / h) requires additional experimental studies.