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ON ENERGY CONSUMPTIONS IN LASER CUTTING OF HIGH-SPEED STEEL SAMPLES
Authors: M.V. NOVOSELOVA,
V.V. IZMAILOV
Abstract: The applicability of a power balance equation for laser cutting of high-speed steel with nitrogen as an assisting gas to improve process efficiency was assessed. Energy parameters obtained experimentally and through theoretical calculations were compared. It was found that material cutting was achieved with an energy per unit melt volume more than 18 J/mm3. The cut surface roughness of the studied samples corresponded to Ra = 1.3…6.8 μm.
Keywords: laser cutting, high-speed steel, energy balance.
SYNTHESIS AND KINEMATIC ANALYSIS OF THE SWING-ROCKER MECHANISM OF A BICYCLE DRIVE
Authors: A.A. GOLOVNIN
Abstract: The article is devoted to the synthesis and kinematic analysis of the lever mechanism of the rear wheel drive of a bicycle, the leading link of which is the usual bicycle carriage with full-turning movement of the cranks. For synthesis and kinematic analysis, a mechanism with the simplest structural scheme, namely a crank-rocker mechanism, has been selected. The general procedure for designing a lever mechanism has been adopted. The selection and justification of the tasks that must be solved during the synthesis and kinematic analysis process have been provided. The selection is justified by the tasks that must be solved during the synthesis and kinematic analysis process. As an indicator of the mechanism efficiency, it is proposed to use the ratio of the angle of the crank stroke to the angle of half a circle arc (180°). For the kinematic analysis, the graph-analytical method is adopted. The plans of velocities and the transfer functions of the mechanism for a number of characteristic positions of the mechanism on the working stroke are given.
Keywords: bicycle drive, crank-rocker mechanism, synthesis, kinematic analysis.
THE METHOD AND THE CHUCK FOR MOUNTING A KEYWAY SHAFT
ON MACHINE CENTERS IMPROVEMENT
Authors: A.P. ARKHAROV
Abstract: An analysis of known methods and chucks for installing shafts on the centers of metal-cutting machines for the processing is presented. The relevance of the work on creating a method and means for installing a shaft with a keyway is noted. The essence of the developed installation method is outlined, in which a keyway coupling is created to transfer torque from the machine spindle to the shaft by automatically placing the shaft on the machine centers and orienting its groove relative to the chuck jaws. The device operating and principle of the designed jaw chuck are disclosed, which also contains a clamp that prevents the shaft from turning when it is oriented in an angular direction as well as jaws for holding the shaft when it is transferred to the center line. Comparative analyzes on the distinguishing features of the created method and chucks with similar known solutions were carried out. The development originality and the achieved technical result are reflected.
Keywords: shaft, installation, keyway, method, thrust centers, jaw chuck, keyway coupling, orientation.
DISTRIBUTION OF ELEMENTAL COMPOSITION IN HIGH-SPEED STEEL AFTER LASER HARDENING
Authors: K.A. SAKHAROV
Abstract: Scanning electron microscopy and X-ray diffraction microanalysis were used to study the microstructure and chemical composition of P6M5 high-speed steel after laser hardening and laser tempering. In the laser hardening zone, almost all primary carbides dissolve in the matrix from the liquid phase, resulting in a highly alloyed solid solution structure and reducing the risk of premature tool failure due to chipping of large carbides in the cutting edge. Patterns of microstructure formation and the distribution of the main alloying elements were established.
Keywords: microstructure, high-speed steel, multichannel laser, scanning electron microscopy, X-ray microanalysis.
RELATIONSHIP BETWEEN ENERGY PARAMETERS OF LASER MELTING
AND MICROSTRUCTURE CHARACTERISTICS OF A NICKEL ALLOY
Authors: M.V. NOVOSELOVA
L.E. AFANASIEVA,
V.V. IZMAILOV,
Abstract: The possibility of using energy balance equations to estimate energy consumption during the deposition and modification of a wear-resistant NiCrBSi coating on a steel surface using powder laser cladding is demonstrated. A number of parameters were used to estimate the energy contribution of laser radiation to the workpiece: dimensional and dimensionless enthalpy, energy density, and a complex of process parameters. The influence of energy parameters on the coating microstructure is demonstrated. The secondary dendritic arm spacing (dendritic parameter) serves as a quantitative characteristic of the microstructure. By optimizing the corresponding energy parameters during cladding or laser surface modification based on the dendritic parameter, it is possible to achieve a coating structure that provides the desired mechanical properties, particularly microhardness and wear resistance.
Keywords: laser cladding, energy parameters, energy balance, dendritic parameter.
ANALYSIS OF MECHANICAL AND DESIGN PARAMETERS OF THE MTF-14 DRUM MILLING CUTTER FROM THE POINT OF VIEW OF THE USE
OF A HYDRAULIC DRIVE DURING MAJOR REPAIRS
Authors: I.M.o. GULIJEV
I.V. GORLOV,
Abstract: This article analyzes the mechanical and design parameters of the MTF-14 drum milling machine drive. It examines the design features of the milling machine drive gearbox and the potential for using a hydraulic drive during overhauls. A comparison of mechanical and hydraulic drives is provided in terms of the potential for using standard components during repairs. The key advantages of a hydraulic drive are described: increased reliability, increased service life of milling machine components, and improved controllability of milling modes. The key hydraulic system parameters required to ensure the operation of the milling machine are established. Recommendations for the practical use of standard components during overhauls are provided, taking into account the selection of modern hydraulic motors.
Keywords: hydraulic drive, drum milling machine, peat machine, hydraulic system, energy efficiency.
A METHOD FOR CALCULATING FLOW-CHANNEL PARAMETERS
FOR AN INCUBATOR SYSTEM INSTALLED AT DEPLETED PEAT DEPOSITS
Authors: A.A. ANDRIANOVA
А.L. YABLONEV,
Abstract: Placing an incubation system in a flow channel of a depleted peat deposit requires hydraulic calculations for both the system itself and the channel. Calculations for the incubation system components (the incubator nest and the supply corrugated PVC pipes) have been previously presented in several articles. This paper describes the authors' developed method for calculating a flow channel and identifying its key parameters – the hydraulic slope of the bottom, the water flow velocity, and the flow rate. An example of a channel calculation using the proposed method is provided. It is noted that a reasonable internal diameter of a corrugated PVC pipe is 25 mm, and the required slope for incubating peled eggs is 0.000 66…0.000 79. Equipment for digging and repairing the flow channel is recommended, and its brief technical specifications are provided.
Keywords: depleted peat deposit, corrugated PVC pipe, incubation system, incubator nest, flow channel, Chezy coefficient, flow rate, hydraulic slope.
ASSESSMENT OF WATER-PHYSICAL PROPERTIES OF LUMP PEAT
WITH APPLICATION OF PEAT MASS HYDROPHOBIZATION
BEFORE FORMING
Authors: A.V. KUPOROVA
Abstract: The article discusses the positive effect of hydrophobization of peat mass before molding on the water-technical properties of sod peat. The results of studies are presented to determine the water-absorbing and water-repelling abilities of sod peat samples. It has been established that the use of hydrophobic additives in the production of lump peat improves the quality characteristics of the initial peat raw materials, has a positive effect on the water-physical characteristics of the finished product, makes it possible to reduce the dependence of production technology on the meteorological conditions of the production region, as well as to reduce the drying elongation to zero due to moisture exchange with the deposit. Application of hydrophobic additives in technology of lump peat production makes it possible to reduce initial moisture content of peat mass before moulding, thus reducing energy costs for production.
Keywords: sod peat, extraction, field drying, hydrophobic additive, technology, water absorption, water-repellent ability.
DETERMINING THE THICKNESS OF A DISK OF A ROLLING SORTING AND SEPARATING DEVICE
Authors: A.V. KONDRATYEV
S.M. KOCHKANYAN,
Abstract: A mathematical model for calculating the thickness of a roll-sorting and separating device is presented. The model allows for the consideration of a complex of dynamic loads arising from the impact of the disk with heavy fraction particles, as well as centrifugal stresses caused by the rotation of the disks. The obtained calculation dependence allows for the establishment of a direct relationship between the kinematic, design, and technological parameters of the roll-sorting device. Based on the model, a graphical interpretation of the influence of the heavy fraction mass, rotational speed, and disk radius on the minimum allowable disk thickness is provided. The practical significance of the model lies in the possibility of rationally selecting disk thickness when designing roller sorting devices for gravel and crushed stone, which contributes to increased reliability and efficiency.
Keywords: roller sorting and separating device, shaft rotation speed, disc thickness, impact load, mathematical model, gravel, and crushed stone.
MAGNETIC LUBRICANTS IN MINING: PHYSICAL AND CHEMICAL PRINCIPLES, TRIBOLOGICAL CHARACTERISTICS
AND APPLICATION PROSPECTS
Authors: А.L. YABLONEV
A.N. BOLOTOV,
Abstract: Extreme operating conditions of mining equipment (abrasive dust, high humidity, shock and vibration loads, a wide temperature range) limit the service life of traditional lubricants and seals. This article presents an analytical review of the physicochemical, rheological, and tribological properties of magnetic lubricating fluids (MLFs) as a class of "smart" fluids and lubricants. Based on a critical analysis of the work of Russian and international authors, this article systematizes data on the influence of magnetite nanoparticle concentration, magnetic field parameters, and friction pair materials on the friction coefficient, wear, and load-bearing capacity of MLFs. The article summarizes the results of experimental tests of MLFs in magnetic fluid plain bearings, shaft seals, belt conveyor rollers, drilling tools, gearbox gears, as well as in magnetic separation processes, magnetoflotation, cutting fluids, and hydraulic fracturing. The tabular presentation presents quantitative indicators for reducing rotational resistance (up to 73 %), increasing water resistance (retaining properties after 24 hours in coal slurry), increasing service life (by 1,6…7 times), gold recovery during magnetic flotation (92…97 % versus 75…82 %), and reducing cutting tool wear (by 50…70 %). Key promising areas are identified: large-gap seals (up to 0,8 mm), hybrid "lubrication and sealing" systems, adaptive magnetorheological dampers, and intelligent monitoring systems for magnetic fluid condition. A forecast for technology development through 2035 is provided.
Keywords: magnetic fluid, ferrofluid, tribological properties, magnetic fluid bearing, magnetic fluid seal, belt conveyor, roller bit, magnetoflotation, cutting fluid, magnetite nanoparticles.
STUDY OF CONTAMINATED FLOW DISCHARGE DURING CLEARING BLOCKAGES IN PIPE-BRIDGES USED IN PEAT RAW MATERIAL ЕXTRACTION
Authors: L.V. LOBACHEVA
D.M. SHCHERBAKOVA,
Abstract: The article is devoted to the study of contaminated flow discharge during the clearance of blockages in pipe-bridges used in peat raw material extraction. Blockages in pipelines (caused by silt, wood debris, and peat residues) lead to water backup in cart channels and reduced extraction efficiency. The study examines changes in hydraulic parameters (pressure, velocity, flow rate) during hydrodynamic cleaning and evaluates the method’s effectiveness. For this purpose, a laboratory setup was created to simulate the discharge process. The principles of hydraulics for pressurized pipelines were applied, including hydraulic calculations using the Bernoulli equation and analysis of experimental data. The research revealed a dependence of outlet pressure on flow density and cross-section configuration, and confirmed the influence of local resistances. Recommendations have been developed to optimize the maintenance of pipe-bridges, aiming to improve the reliability of drainage systems.
Keywords: peat raw material extraction, pipe-bridges, contaminated mass, trench, Bernoulli’s equation, outlet cross-section, pressurized pipeline.
ALGORITHM FOR THE APPROXIMATE SOLUTION OF OPTIMAL CONTROL ON AN INFINITE HORIZON
Authors: Yu.N. MATVEEV
O.D. BELOVA,
Abstract: The article addresses the problem of finding an approximate solution to the optimal control problem over an infinite horizon through the synthesis of an optimal feedback control law for dynamical systems. A sequential reduction scheme is proposed to transition from a continuous problem formulation to a finite-dimensional discrete model. The method of successive approximations is applied to solve the resulting system of dynamic programming equations.
Keywords: optimal control; feedback control synthesis; dynamic programming; Bellman equation; method of successive approximations; discretization.
APPLICATION OF REGRESSION MODELS FOR PARTIAL AUTOMATION
OF WORKLOAD ESTIMATION IN IT PROJECTS
Authors: K.A. KARELSKAYA,
R.A. LUKYANOV,
Abstract: The article is devoted to the study of the potential of using regression models in the context of iterative-incremental methodology of IT project management. The first section of the paper reveals the theoretical foundations and methodological approaches underlying this area. The second part focuses on practical experience, as well as practical experience in setting up and developing regression models. as well as analyzing their effectiveness in assessing labor costs and resource planning, which contributes to improving the accuracy and effectiveness of management decisions in the field of information technology. Their effectiveness in assessing labor costs and resource planning in the field of information technology is considered.
Keywords: regression model, data scaling, machine learning, automation, evaluation of machine learning metrics, flexible methodology, AGILE, IT project management.
PLANNING AND OPTIMIZATION OF LINEAR CUTTING OF METAL PRODUCTS USING INTEGER PROGRAMMING METHODS
Authors: A.V. IVANOV,
Yu.N. MATVEEV
Abstract: The article considers the problem of optimal linear cutting of metal products in the production of reinforced concrete structures. The relevance of reducing production waste in the construction industry is substantiated. A three-stage methodology is described that combines the formation of cutting plans, the application of integer linear programming methods, and a procedure for selecting the optimal solution. The mathematical formulation of the integer linear problem is given and an applied example of cutting reinforcing bars is considered. The practical significance of the developed approach for minimizing metal waste at industrial construction enterprises is shown.
Keywords: linear cutting, metal products, integer linear programming, waste minimization, optimization.
AUTOMATED DECISION SUPPORT SYSTEM FOR PERSONALITY IDENTIFICATION TASKS USING VISUAL DATA
Authors: E.E. FOMINA
Abstract: The article presents an automated expert system for supporting decision-making in forensic medical identification of individuals using photo and video materials. The system is built on a modular principle, which ensures flexibility and the possibility of integrating new analytical algorithms. Special attention is given to the comprehensive extraction of both quantitative and qualitative biometric features, including analysis of the red border of the lips, the auricle, prediction of sex and racial affiliation, as well as gait analysis. Each module is focused on extracting specific features to form an individual profile. The decision support module aggregates data, performs weighted matching with a database of known individuals, and generates a final conclusion. The developed system enhances the objectivity, accuracy, and speed of identification by automating labor-intensive processes.
Keywords: automated system, decision support, identity verification, biometric identification, photographic materials, video materials.
SOLVING THE FORECASTING PROBLEM FOR SEQUENCES WITH AN ULTRA-LARGE NUMBER OF TIME SERIES
Authors: S.V. ALEKSEEVA,
S.A. VOINASH,
N.N. WERNER,
V.A. SOKOLOVA,
S.L. GOROBCHENKO
Abstract: This article addresses the problem of forecasting sequences containing an extremely large number of time series (up to 300,000 or more) characterized by non-stationarity, heterogeneity, and seasonality. The problem of choosing the optimal forecasting method is considered using sales data from a large distribution network as an example. The study provides a comparative analysis of several time series models implemented in Python libraries (pmdarima, statsmodels, skforecast, statsforecast, sktime), including ARIMA, SARIMA, and their modifications with exogenous factors (ARIMAX, SARIMAX). The choice of the most effective SARIMAX model is justified based on minimizing the RMSE error. To improve computational efficiency when working with large data sets, an approach is proposed based on preliminary clustering of series using the k-means, Euclidean, and DTW methods, as well as optimizing the number of clusters using the elbow and silhouette methods. It is shown that forecasting based on cluster centroids followed by inverse normalization significantly reduces computation time without critically losing accuracy. The results confirm the effectiveness of the proposed approach for generating reliable forecasts in supply chain management systems.
Keywords: time series, forecasting, big data, clustering, exogenous variables, k-means method, machine learning, Python, optimization, data analysis.