The influence of the number of rollers and their diameter on the stiffness of a roller bearing is under investigation. It is found that, in the absence of radial clearance in a roller bearing, stiffness is a linear function of the number of rollers and is independent of the loading pattern. In the presence of clearance, the dependence of stiffness on the number of rollers is nonlinear and depends on the position of the rollers relative to the load line. It is shown that roller bearing stiffness is independent of roller diameter under any loading pattern.
The paper examines the nominal geometric parameters of YaMZ engine valves and their permissible deviations during defect identification and incoming quality inspection. Based on the evaluation of sorting results, it is recommended to replace the micrometer MK-25 used for inspection with the SI-25TsG digital indicator gauge with a digital head and a readout accuracy of 0.001 mm.
The design and operating principles of new rotary pulsation devices are described. The working cavity of these devices includes additional dispersion elements, whose interaction with the other components in the medium produces turbulent pulsations with velocity vectors in arbitrary directions. That increases the speed of particle flow through the heterogeneous medium and intensifies emulsification, dispersion, and mass transfer.
The design of air-centrifugal classifiers (ACCs) for separation of powders by density and size are considered. The influence of an additional tangential airflow on the boundary size of the separated fractions is under investigation. The ACC parameters are calculated based on the balance of centrifugal and aerodynamic forces acting on the particles. Computer modeling of the airflow and particle trajectories in a dust-gas environment inside the ACC confirms the effectiveness of introducing an additional flow to regulate the classification process.
The temperature at the working surface of a cutter in machining is analyzed. A method is developed for predicting the temperature of a tool’s working surfaces so as to select the optimal turning conditions and working life, while maintaining specified quality of machining.
This article presents the results of plasma surfacing of VT6 titanium alloy using reciprocating feed of 3- and 5-mm-diameter filler wires. Key aspects of upgrading a plasma surfacing system for large-diameter wires in a controlled-atmosphere chamber are discussed. It was established that a single plasma arc is insufficient for high-quality melting of 5-mm-diameter wire; good results were achieved only by using two plasma arcs arranged in a V-shape relative to the vertical feed of the filler wire. Using reciprocating feed of large-diameter wire allows for high-quality formation of the deposited metal, free of defects and with high mechanical properties, across various trajectories of the welding head.
The article substantiates the need to analyze risks associated with the interconnection schematics and assembly sequences of key components of an electric vehicle, such as the high-voltage battery and power electronics. The specific risks arising from improper assembly and connection are considered, including thermal runaway, short circuits, contact overheating, and malfunctions of the battery management system (BMS) or the inverter. The influence of the requirements of the international standards of functional safety ISO 26262 and electrical safety ISO 6469 on the processes of designing interconnection schematics and developing assembly sheets is analyzed. The article demonstrates that conventional FMEA methods are inadequate for assessing complex risks of electric vehicles and proposes instead a systematic approach based on Automotive Safety Integrity Levels (ASIL) and Hazard Analysis and Risk Assessment (HARA). Approaches to integrating assembly risk analysis into the ANPQP quality management methodology at all stages of the life cycle, from planning and design to verification and mass production, are considered. Special attention is given to environmental cleanliness controls, tightening torque validation, and operation traceability. The results of the study confirm that successful implementation of the strategy for ensuring the safety and reliability of electric vehicles requires systematic control of the assembly and connection processes, which are fundamental factors that influence final product quality.
The use of hierarchy analysis in assessing the quality of cylinder components in UNBT mud pumps is considered. Expert assessment is employed, as well as an approach integrating engineering, technological, and economic considerations. Three designs are considering in selecting the optimal component.
In-process testing has established that using the newly developed VIKSBOR abrasive wheels made of cubic boron nitride with intermittent dressing significantly improves the cost and environmental efficiency of creep-feed profile grinding of turbine blades made from nickel-based superalloys.
The great majority of modern machine-building production is based on the principle of small-scale production. This can be explained, first of all, by adaptation to the high dynamics of changes in consumer requirements. The lack of timely response leads to a decrease in the competitiveness of the enterprise and, ultimately, to its unprofitability. Small-scale production is characterized by a large range of products and a high frequency of launch into the technological system for manufacturing. Under these conditions, a rational character of the current loading of the technological system takes on a special role, since at the same time the productivity of production increases, the cost of its manufacture decreases and the throughput increases. Solving the problem by increasing the load level of the technological system turns out to be quite appropriate. One way to solve the problem is to constantly monitor the state of the technological system, on the basis of which decisions are made to change the distribution of operations of technological processes that are carried out within the technological system. The solution to this problem is based on the digitalization of information about the properties of the technological system and production tasks. The main mechanism of the search process is the modeling of the entire production process as a whole and the generation of various options from which the best solutions are selected.
The wear of disc harrow components is one of the key problems affecting tillage efficiency and agricultural product quality. Disc harrows are widely used in the agricultural sector for various operations, including plowing, harrowing, and seedbed preparation. However, over time, their components experience significant mechanical and physical stress, resulting in reduced tillage performance and shortened equipment service life. An in-depth analysis of wear mechanisms and identification of their contributing factors become necessary for optimization of the operation of disc harrows and improvement of the economic efficiency of agricultural production.
In this paper, we propose a hybrid graph-vector language model that combines both approaches. The model constructs a weighted semantic graph based on local textual contexts, capturing synonymy, part–whole, and associative relationships. The graph is then transformed into a vector representation using a modified Weisfeiler–Lehman markup procedure, which allows the use of standard classifiers without reworking the existing computing architecture.
The article substantiates the need to develop an adapted digital-system quality management (ANPQP) framework for electric vehicles in the context of import substitution and technological sovereignty. Attention is given to the specific risks associated with high-voltage systems, thermal runaway, and hardware–software interaction, as well as the limitations of conventional APQP and FMEA tools. The influence of the requirements of the standards of functional safety ISO 26262 [1] and electrical safety ISO 6469 [2] on design and verification processes is analyzed. A comprehensive approach is proposed, including a modified 6-point risk assessment scale, an integrated lifecycle matrix (ILCM), and computer-aided engineering (CAE) analysis for quality forecasting. The integration of digital platforms (Jira, Confluence, PLM) into the concept of end-to-end data traceability is substantiated. Methods of calculating an integrated indicator of quality and economic impact that showcase redirection of resources towards prevention are considered. The results of practical tests on a Russian-produced electric vehicle project confirm a 30
In the context of digital transformation, high-tech enterprises are faced with a need for continuous innovation. The effectiveness of innovative activity depends not only on technological potential, but also on the internal organizational environment, including knowledge management and internal marketing. This study combines the approaches of knowledge management, internal marketing, and strategic management to analyze their impact on the innovational activity of high-tech enterprises. The methodological basis of the research includes comparative analysis, systematization of practices, and case studies of leading companies in IT, biotechnology, and aviation. The results show that knowledge management promotes the creation and dissemination of knowledge, internal marketing promotes employee engagement and motivation, and the combined use of these factors maximizes the company’s innovational activity. The practical significance of the research lies in the possibility of using the proposed approaches in the development of corporate strategies for innovative development and personnel management. The limitation of the research is the focus on large high-tech companies, which opens up opportunities for further empirical research using quantitative methods.
The occupational health and safety information system of a machine-building enterprise is designed to prevent occupational injuries and diseases through risk management and safety control of working conditions. According to the ISO 45001 international standard, the purpose of an occupational health and safety management system is to create an environment for managing safety and health risks to prevent injury and damage to workers’ health and ensure safe working conditions. Modern occupational safety information systems can be constructed in different ways. The main approaches are a centralized architecture (a single platform for the entire organization) and a decentralized (distributed) architecture (several local subsystems by departments or functions). Let us consider their features and their advantages and disadvantages in the context of a large machine-building enterprise.
Complex housing components are analyzed. The possibility of finishing such components by vibrational water jet machining in a fine-grain medium is considered. The expediency of diluting the fine-grain working medium is discussed. The flow rate of the incoming liquid, the height of the abrasive, the vibrational parameters of the abrasive medium, its grain size, and the treatment time required for finishing are determined.
A closure equation is derived for a mathematical model describing the operation process of a gas turbine engine (GTE) with a free turbine, also known as a split-shaft engine. It is demonstrated that two closure equations are required: the first equation is universally applicable to all types of GTEs, whereas the second equation takes a certain form depending on the particular GTE type.
The influence of gyroscopic reactions on dynamic processes in a rotor–bearing system is under investigation. An experimentally validated mathematical model of a rotor–bearing system is presented that allows reproducing the features of nutation and precession motion during transient and steady-state rotor operation. It is established that stable precession motion is maintained by forces simulating the interaction of the rotor with the clutch, which depends on the angular deviation of the rotor. It is shown that active relay control reduces rotor oscillations. Switching occurs at the moment of velocity sign reversal.
The development of the digital economy is significantly transforming the competitive environment of high-tech markets. Under these conditions, the brand becomes an important strategic asset of the company, ensuring the formation of sustainable competitive advantages, consumer trust, and investment attractiveness. Brand positioning plays a special role, allowing high-tech companies to differentiate innovative products and create unique value for consumers. The purpose of the study is to analyze the brand positioning strategies of high-tech companies in the digital economy and identify the factors determining their effectiveness. The methodological basis of the research consists of methods of comparative analysis, a systematic approach and a case study of the practices of leading technology companies. The research results show that the most effective positioning strategies are those of technological leadership, ecosystem branding, digital customer experience orientation, and building trust in innovation. The results obtained can be used in the development of marketing strategies of high-tech companies in the context of the digital transformation of the economy.
Formulas are obtained for the accumulated strain in different regions of the workpiece. A method is outlined for taking the hardening of the deformed material into account in designing extrusion processes or producing square profiles from cylindrical workpieces.
