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ON THE INFLUENCE OF HARDENING TREATMENT OF FRICTION SURFACES ON THE RESOURCE OF TRIBOCOUPLE
Authors: V.V. IZMAILOV, Dr. Sc., M.V. NOVOSELOVA, Cand. Sc.
Abstract: An empirical formula is proposed to describe the dependence of the hardness (microhardness) of the material H on the depth h, which is a consequence of hardening during the processing of a part or the use of hardening technology. The formula contains two empirical parameters characterizing the degree of hardening of the material and the thickness of the hardened layer. The proposed analytical dependence H(h) made it possible to generalize the well-known in tribology Archard’s equation, which relates the wear rate to the hardness of the material of the wear part, to the case of contact of parts with a hardness variable over the depth of the material. Based on the generalized Archard’s equation, a formula was obtained for quantitative prediction of the frictional interface resource by the criterion of admissible linear wear. The quantitative assessment of the resource is the maximum value of the friction path. The influence of the parameters of the hardened layer on the estimation of the value of the frictional coupling resource and its error arising when determining the resource without taking into account the hardening of the surface layer is analyzed. It is shown that this error can be significant, especially for a significant degree of hardening.
Keywords: friction, wear, surface hardening, resource, prediction.
THE INFLUENCE OF THE MAGNETIC FIELD ON THE PERFORMANCE PROPERTIES OF LUBRICANTS
Authors: A.N. BOLOTOV, Dr. Sc., G.B. BURDO, Dr. Sc.
Abstract: The effect of the magnetic field on the physicochemical and tribotechnical properties of traditional lubricants and innovative nanostructured magnetic oils and liquids is considered. The reasons for changing these properties are analyzed. It is shown which factors primarily affect the polarizability of oils and the absorption of electromagnetic radiation. Methods of dielometry and infrared spectroscopy were used to evaluate the physicochemical properties. The integral effect of the magnetic field on the friction process of surfaces lubricated with traditional non-magnetic and magnetic oils was studied on an end friction machine. It is concluded that there is a significant change in individual physico-mechanical and chemical properties of magnetic lubricants under the influence of a magnetic field. A magnetotribological effect has been established, consisting in the influence of a homogeneous magnetic field on the lubricating properties of magnetic oil. The effect of homogeneous magnetic fields on the anti-wear properties of the oil is described. It is concluded that the field reduces the aggregative stability of the magnetic oil.
Keywords: magnetic nano oil, friction, wear, magnetic colloid, polymer shells, viscosity, lubrication
ENERGY PROPERTIES SURFACES LUBRICATED WITH MAGNETIC NANOSLUBRICATION
Authors: A.N. BOLOTOV, Dr. Sc., G.B. BURDO, Dr. Sc.
Abstract: The dynamics of changes in the contact potential difference between metal surfaces lubricated with magnetic oil and its components has been studied. It is shown that the lubricating properties of the studied liquids correlate with the magnitude of the change in the contact potential difference after their application. In order to predict the operational properties of friction units lubricated with magnetic oil, specific physical and chemical features of processes occurring on solid surfaces after applying magnetic lubricant have been studied in detail. Estimates of the energy changes occurring on the surface after applying magnetic oil to it were made based on the work of the electron output. The effect of dispersed magnetite particles on the output operation was studied using a two-component magnetic oil. Magnetite particles adhere to the surface under the action of Van der Waals or dipole interaction and partially shield it. It follows from the data obtained that the addition of magnetic particles to the triethanolamine liquid does not lead to a significant change in the output operation over the entire time range. At the same time, magnetite particles covered with a layer of adsorbed fatty acid molecules increase the work of the electron output.
Keywords: magnetic fluid, surface, electron work function, operational properties.
MULTILAYER NANOSTRUCTURED COMPOSITE COATINGS FOR MILLING CHROMIUM-NICKEL ALLOYS
Authors: M.Sh. MIGRANOV, Dr. Sc., E.V. ISAEV, Chief Researcher,
A.M. MIGRANOV, Researcher, I.I. MOSENZ, Chief Researcher,
A.S. GUSEV, Postgraduate, S.S. OPLESNIN, Researcher
Abstract: The paper presents the results of experimental studies of wear resistance of end mills with multilayer composite coatings during blade cutting of chromium-nickel alloys, which are widely used in critical, heavy-duty and high-temperature tribocontours of aerospace equipment. Promising and innovative wear-resistant coatings obtained on different installations and by different technologies are investigated.
Keywords: end mills, multilayer composite coatings, chromium-nickel alloys, heavy-duty and high-temperature tribocouplings.
INTEGRATED ASSESSMENT OF WEAR OF CUTTING TOOLS AND COMPOSITE COATINGS WITH THE EFFECT OF ADAPTATION
Authors: M.Sh. MIGRANOV, Dr. Sc., A.M. MIGRANOV, Researcher
Abstract: In the work on the basis of thermodynamics of nonequilibrium processes the methodology of research of wear of cutting tools and wear-resistant coatings with effect of predictable adaptation of friction surfaces is developed. The use of the methodology will make it possible to evaluate the self-organization of the tribosystem during metal cutting, will provide a scientifically validated approach to the selection and application of tools and cutting conditions with predictable properties of self-organization during friction. The proposed principles of selection and application of tool materials and wear-resistant coatings will significantly improve the efficiency of blade cutting machining.
Keywords: plastic deformation, cutting temperature, thermodynamics of nonequilibrium processes, tribosystem, self-organization, predictable adaptation, level and interval of self-organization.
THIN-WALL WORKPIECE AUTOMATIC REINSTALLING ON THE MANUFACTURY MACHINERY
Authors: A.P. ARKHAROV, Cand. Sc.
Abstract: The analysis of the known methods of thin-wall workpieces automatic reinstalling is carried out. Their advantages and disadvantages are revealed. The essence and implementation of the developed thin-wall bushing reinstallation method are disclosed. It is compared according to essential features with similar known solutions. The originality of the method and the achieved technical result are reflected.
Keywords: automation, reinstallation, method, workpiece, fastening, chuck, accuracy
COMPARATIVE PERFORMANCE ASSESSMENT
GROOVED ROLL SECTIONS
Authors: A.V. KONDRATYEV, Dr. Sc., S.M. KOCHKANYAN, Cand. Sc.,
T.I. LYSENKO, Senior Lecturer, A.A. GUSAROV
Abstract: The article presents the results of comparative studies of the efficiency of trough-shaped sorting with two types of intensifying devices – movable aprons and auger intensifier. Evaluation of the efficiency of roll sorting was carried out on the basis of multifactorial planning of the experiment for the rational parameters of the considered options for separating devices when fractionating the gravel mixture.
Keywords: trough-type swath sorting, movable aprons, auger intensifier, auger speed, disc speed, apron speed, material feed, screening efficiency, gravel
ANALYSIS OF THE FORCES AFFECTING A PARTICLE OF MILLING PEAT IN THE ZONE OF THE SUCTION FLUE OF A PNEUMATIC HARVESTING MACHINE
Authors: А.L. YABLONEV, Dr. Sc., D.M. SCHERBAKOVA, Postgraduate
Abstract: The suction efficiency of milling particles by pneumatic peat harvesters is largely determined by the air flow rate created by the pneumatic system. Attempts to analytically determine this speed were made by a number of scientists not only for peat, but also in related industries ‒ in the dedusting and pneumatic transport of sawdust. However, due to the specifics of peat milling chips, the topic is raised again. In the course of the study, it was found that the separation of a peat particle from the underlying surface is not affected by the Magnus force, but by the lifting force caused by the pressure difference above and below the particle. Mathematical models have been developed that make it possible to calculate the minimum air flow speed required to move a peat particle from its place and detach it from the underlying surface.
Keywords: peat, pneumatic peat harvester, suction nozzle, air speed, drag force, lifting force, Magnus force, Bernoulli equation
MULTIPELLISTOR THERMOCHEMICAL DETECTOR FOR GAS CHROMATOGRAPHY
Authors: L.V. ILYASOV, Dr. Sc.
Abstract: The results of new thermochemical detector development for combustible gases determination are discussed. Detector is denoted as multi pellistor thermochemical detector (MPTD) and produced using thermochemical sensitive point tribrach sensing elements type 2 (PTSE-2). Detector contains assembly of four measuring pellistor elements and four sensitive comparationpellistor elements, positioned the way so that their holders to form flow chamber. Pellistors are placed on the flow chamber central axis. Experimentally it was fond that for complete combustion of methane, that considered to be the most stable gas for catalytic oxidation, four sensitive measuring and four sensitive comparison elements are needed.
Mathematical model of detector signal is described and procedure of qualitative data obtaining using this model discussed. Possibility of MPTD application in gas chromatograph was shown experimentally in case of chromatograph operation using air or helium as carrier gas. Possibility of MPTD application in gas analyzing systems for determination of low volume combustion heat of hydrocarbon containing gases, and in self calibrate chromatographs was shown.
Keywords: thermochemical detector, multi pellistor, chromatograph, combustible gases and vapors
ALGORITHM FOR FRONTAL SIMULATION IN EMERGENCY RELEASE
ANALYSIS AND VISUALIZATION SYSTEM
Authors: Yu.N. MATVEEV, Dr. Sc., L.O. CHERNYSHEV, Postgraduate
Abstract: The article considers a frontal approach to building a cell model for prompt response to local releases of hazardous chemical substances into the atmosphere. A front modeling algorithm based on a hexagonal pattern of a two-dimensional grid is briefly described and solutions are proposed to ensure stability of the forecast result. In the objective function of solution search, the maximal convolution of partial criteria is applied. Examples of estimating model parameters based on Gaussian equation solutions as well as data from field observations are considered. The time plots for finding a solution when changing the level of detail of the contamination zone are given.
Keywords: operational response, data assimilation, frontal algorithm, cell model, performance
RAPID ALERT SYSTEM FOR BLAST FURNACE TUYERE BURNOUT
Authors: M.Yu. RYABCHIKOV, Cand. Sc., E.S. RYABCHIKOVA, Cand. Sc.,
E.S. MUKHINA, Senior Lecturer, M.A. TARASOV, Student
Abstract: The work is aimed at improving the existing methods for predicting tuyere burnout using a well-known technological parameter characterizing the drop in cooling water flow at the tuyere inlet and outlet. A distinctive feature of the proposed system is a two-level forecast in the form of an alert and a burnout warning. The forecast is based on an automated analysis of the retrospective data on the statistical properties of the drop in the cooling water flow rate. The paper gives examples of the changes dynamics in the difference of the of cooling water flow rate on the tuyere prior and directly during the burnout. We presented the structure of the alert system and examples of its operation in cases of gradual and avalanche-like development of the burnout.
Keywords: tuyere burnout, blast furnace, forecast, dispatch control, processing of retrospective data