The article presents the algorithm for the numerical studies on the model of contact temperature fields arising in a reinforcing steel plate welded to a modernized locomotive frame (for an electric locomotive VL80с), an algorithm and a program for the MathCAD 15 programming environment were developed.

Gearboxes used in electric locomotives are a critical unit, especially in freight rolling stock. The article presents the calculation of the main parameters of the two-way oblique traction transmission of the VL-80s electric locomotive (which is operated on the railways of Uzbekistan) based on a comprehensive analysis of the diagnostic parameters obtained using the Poisson normal distribution method for the identified failures according to the Uzbekistan depot data. Also, a Pareto diagram was constructed for the chassis of 3VL-80s electric locomotives based on the data of the Locomotive Operation Department of JSC Uzbekistan Temir Yollari, and probabilistic and statistical analyses of the failures and breakdowns of the wheel pair and the large gear wheel of the traction gearbox of the VL-80s electric locomotives were carried out. An algorithm and methodology for assessing the reliability of the large gear wheel of the traction gearbox of an electric locomotive are presented. As a result of a numerical calculation of the coefficients of the empirical regression equations using approximation and spline interpolation methods, a regression equation was obtained for the dependence of the standard deviation of the wear of the tooth of the large gear wheel of the traction reducer of the VL80s electric locomotive on the mileage.

The article presents a theoretical justification for the development of a test bench for dynamic durability tests of locomotive bogie frames, a theoretical justification for dynamic loading modes in order to bring the test conditions closer to real ones. In connection with the mass failure of electric rolling stock for JSC "Uzbekiston temir yullari" it is necessary to develop a new bench for testing the dynamic strength of bogie frames for locomotives with electric power transmission to wheelsets, which can be used to conduct bench endurance tests of bogie frames for locomotives on dynamic strength in order to extend the service life for factory repairs at locomotive repair plants. The proposed design of the stand for dynamic testing of electric locomotive bogie frames has a scientific novelty, which is protected by the Patent of the Republic of Uzbekistan for invention No. IAP 06795 [1] and has no analogues in the world.

This study presents multi-objective geometric optimization of a modular friction disk cutter for spur gear thermo-friction processing within the ANSYS Workbench 2024 R1. The integrated workflow—Geometry → Steady-State Thermal → Static Structural → Design of Experiments → Response Surface → Response Surface Optimization—enables selection of a rational tool geometry within a single parametric model. Variable dimensions (a, b, c) describe the load-bearing part: a characterizes the transitional thin profile zone, b is the massive supporting part, and c is the intermediate disk thickness controlling thermo-mechanical load transmission. Dimension c most significantly influences equivalent stresses and directional deformation, while maximum temperature depends on combined a and c effects. Based on Response Surface Optimization, the rational solution domain is concentrated near $a\approx 3 \mathrm{m}\mathrm{m}$, $b\approx 10 \mathrm{m}\mathrm{m}$, and $c\approx 4 \mathrm{m}\mathrm{m}$, yielding $P4\approx 33.306 \mathrm{M}\mathrm{P}\mathrm{a}$, $P5\approx 295.93 °\mathrm{C}$, and $P6\approx -5.7488·{10}^{-5} \mathrm{m}$. These values demonstrate a sufficient calculated safety margin within the finite element framework, providing a technically justified direction for prototype manufacturing. Although currently evaluated as purely computational without direct full-scale physical measurements, these results establish a foundation for subsequent experimental validation using thermal imaging and optical deformation analysis. Future research will focus on transient thermo-mechanical modeling with impulse cooling and experimental verification.

The engine is one of the most important and complex parts of the car. Most of the breakdowns occur in the piston group of the internal combustion engine, especially in the compression rings. This article presents a new design for an innovative repair kit for transport equipment units. Article...

This study investigates the effect of surfacing with Sv-10Х17Т welding wire on the tribological properties of steel samples. The research is motivated by the need to extend the service life of components operating under frictional loads while reducing the maintenance and repair costs. The focus is on a key element of the pipeline shut-off valves, the wedge of a wedge gate valve, which experiences high contact stresses and severe wear during operation. Laboratory tests were conducted under various friction conditions, involving dry friction, water-based media, and oil-based media. Parameters, such as the coefficient and moment of friction, contact temperature, mass loss, wear depth, surface microhardness (both before and after testing), and surface roughness (Ra), were systematically measured. Experiments with steel samples surfaced using Sv-10Х17Т welding wire were designed to replicate actual valve working conditions. The results showed that Sv-10Х17Т surfacing significantly increased wear resistance, reduced friction, and enhanced surface microhardness, particularly under prolonged dry friction. The microstructural analysis confirmed the formation of a hardened riveted surface layer with deformation strengthening and partial thermal treatment. These findings indicate that Sv-10Х17Т surfacing not only restores, but also improves the performance of the steel components, offering an effective method to extend the operational life. The outcomes of this research have practical value for mechanical engineering, as well as the repair and maintenance of pipeline equipment, turbines, gearboxes, bearings, valves, and other critical components.