Browsing by Author "Bulakh, Maryna"

Now showing 1 - 3 of 3

Determination of the Filler Concentration of the Composite Tape
(MDPI, 2022) Baranovskyi, Denys; Myamlin, Sergey; Bulakh, Maryna; Podosonov, Dmytro; Muradian, Leonty
ENG: For the first time, a theoretical dependence was obtained to determine the filler concentration of the composite tape. On the basis of this dependence, a composite tape with variable mechanical and tribological properties can be obtained. It is proposed that the composite tape is welded onto the cylindrical surface of the central bowl of the rail truck bolster. The bench tests made it possible to determine the degree of wear of the central bowl of the rail truck bolster by means of a welded composite tape. The wear value of the central bowl of the rail truck bolster with welded-on composite tapes is 0.15–0.18 mm per 10,000 km of a freight car’s mileage. The predicted service life of the central bowl of the rail truck bolster with a welded-on composite tape is 320–420 thousand km.
Determination of the Risk of Failures of Locomotive Diesel Engines in Maintenance
(MDPI, 2023) Baranovskyi, Denys; Bulakh, Maryna; Michajłyszyn, Adam; Myamlin, Sergey; Muradian, Leonty A.
ENG: This article presents a mathematical model of the risk of failures, depending on the operating parameters, of locomotive diesel engines. The purpose of this study is to determine the risk of failures of locomotive diesel engines in maintenance. The theory of probability and the theory of logic and reliability are used in this theoretical study. The innovations and main works are the first approaches to calculating the risk of failures of locomotive diesel engines by hourly fuel consumption, which, under operational conditions, allows for extending the life of locomotive diesel engines during maintenance. As a result, a maintenance process for 5D49 diesel engines is developed in a locomotive depot. When managing the maintenance processes of 5D49 diesel engines in the locomotive depot, it is determined that the optimal mileage is 45,000 km. The resource of 5D49 diesel engines in the locomotive depot increased by 2.4% in the management of the maintenance process compared to the existing maintenance system.
Increasing the Corrosion Resistance of the Center Plate Unit in Railway Freight Car
(Politechnika Lubelska, Lublin, Poland, 2025) Bulakh, Maryna; Bieniaś, Jarosław; Ostapiuk, Monika; Molchanov, Dmytro; Lunys, Olegas; Muradian, Leonty
ENG: One of the most damage-prone components of a freight car is the center plate, which is highly susceptible to wear and corrosion. This study investigated the application of a composite coating based on a FeCrNi alloy with the addition of chromium carbide (Cr₃C₂) to protect the steel surfaces of the center plate from corrosion and mechanical degradation. The coating was applied using laser cladding and subjected to comprehensive testing, including electrochemical analysis (OCP, polarization, and electrochemical impedance spectroscopy), microhardness measurements, and microstructure evaluation using scanning electron microscopy (SEM). The results showed that the coating exhibited a stable corrosion potential, low corrosion current density, and high impedance at low frequencies, indicating good protection against ion penetration and electrode reactivity, while significantly improving the microhardness of the base material. This study demonstrates the potential of the modified FeCrNi-based coating in extending the service life, enhancing the operational reliability, and increasing the corrosion resistance of center plates in freight cars.