Showing papers in "Journal of Machinery Manufacture and Reliability in 2014"
TL;DR: Different mechanisms of parallel structure synthesized and patented by the employees of the A. A. Blagonravov Institute of Machine Science, Russian Academy of Sciences, are considered as mentioned in this paper.
Abstract: Different mechanisms of parallel structure synthesized and patented by the employees of the A. A. Blagonravov Institute of Machine Science, Russian Academy of Sciences, are considered. Mechanisms have different degrees of freedom and different numbers of connecting kinematic chains. They are meant for different technical applications.
27 citations
TL;DR: In this paper, the basic results of fundamental and applied studies obtained by the Department for Strength, Survivability and Machine Safety, in the framework of cooperation with the leading foreign and Russian scientific centers within the recent years, are presented.
Abstract: The basic results of fundamental and applied studies obtained by the Department for Strength, Survivability and Machine Safety, in the framework of cooperation with the leading foreign and Russian scientific centers within the recent years, are presented. Modern trends in the problems of strength, service life, survivability and safety of machines and structures are discussed. The prospective directions of scientific investigations at the modern stage of development of machines science are discussed.
23 citations
TL;DR: In this article, the authors considered nonstationary contact problems with moving boundaries for two elastic cylindrical or spherical Timoshenko-type shells and obtained a system of resolvent equations using the superposition principle.
Abstract: Nonstationary contact problems with moving boundaries for two elastic cylindrical or spherical Timoshenko-type shells were considered. A system of resolvent equations has been obtained using the superposition principle. Influence functions for the shells in the form of Fourier expansions have been found. A numerical-analytical solution algorithm has been constructed and implemented.
23 citations
TL;DR: In this article, an axisymmetric problem of hydroelastic vibrations of the walls of a channel with a pulsating layer of a viscous incompressible fluid is investigated, where the channel walls are formed by the concentric circular three-layer elastic plate and absolutely solid disk with an elastic coupling.
Abstract: An axisymmetric problem of hydroelastic vibrations of the walls of a channel with a pulsating layer of a viscous incompressible fluid is investigated. The channel walls are formed by the concentric circular three-layer elastic plate and absolutely solid disk with an elastic coupling. The laws of motion of the channel walls, their amplitude and phase frequency characteristics, as well as the hydrodynamic parameters of the fluid layer in the channel are found. An example of the computation of resonance vibrations of a hydromount with a three-layer elastic structural element is shown.
19 citations
TL;DR: The works presented at the meeting of the enlarged Academic Board devoted to the 75th anniversary of the Blagonravov Institute of Machine Science (IMASh RAS) are reviewed.
Abstract: The works presented at the meeting of the enlarged Academic Board devoted to the 75th anniversary of the Blagonravov Institute of Machine Science (IMASh RAS) are reviewed. The main stages of the scientific and reorganization activity of the institute are briefly described and both traditional scientific research lines and the results of the most advanced developments including applications of wave techniques in various industries are reported.
16 citations
TL;DR: In this paper, the operation of a magnetorheological transformer in which choke channels are replaced with a cylindrical clearance between two coaxial cylinders is considered, as well as the working and compensation chambers, are filled with a magnetic fluid.
Abstract: The operation of a magnetorheological transformer in which choke channels are replaced with a cylindrical clearance between two coaxial cylinders is considered. The cylindrical clearance, as well as the working and compensation chambers, are filled with a magnetorheological fluid. It has been shown that this design of the magnetorheological transformer is preferable for damping impact loads.
14 citations
TL;DR: In this paper, the Institute of Machine Science has become the national center for the development of machine science as one of the principal trends in engineering sciences in the Soviet Union and Russia.
Abstract: Taking into account basic scientific and applied problems set by the Russian Academy of Sciences, the Institute of Machine Science has become the national center for the development of machine science as one of the principal trends in engineering sciences in the Soviet Union and Russia, that form the basis for the development of most sectors of the domestic machine building industry. The development and generalization of results of studies of strength and service life of structural bearing elements has been considered one of the Institute’s principal areas of activity. One of the most important tasks in perspective will be to improve traditional and new approaches to solving a complex of interrelated tasks on strength, service life, survivability, risk, safety, and security on the basis of results of past and future basic studies and applied developments in this field.
11 citations
TL;DR: In this article, the authors provided the results of simulating the stress state of Novikov gearing wheel teeth influenced by the load distributed over the contact area and made on the basis of the standard reference profile with two bending intensity concentrators.
Abstract: This paper provides the results of simulating the stress state of Novikov gearing wheel teeth influenced by the load distributed over the contact area and made on the basis of the standard reference profile with two bending intensity concentrators. The simulation was carried out in the finite element environment ANSYS when solving the spatial contact problem. The dependence for determining the parameter that takes into account the longitudinal extent of the contact area and the influence of various geometrical factors is obtained. The graphs and tables presenting the results of studying the stress changes in the gearing are provided up to the face contact, which is necessary when studying the transmission work in conditions of multipair gearing.
10 citations
TL;DR: In this paper, a model of the relaxation of the nonequilibrium structure of grain boundaries in bulk nanomaterials, which are produced by deformation methods, under an ultrasonic wave effect is proposed.
Abstract: A model of the relaxation of the nonequilibrium structure of grain boundaries in bulk nanomaterials, which are produced by deformation methods, under an ultrasonic wave effect is proposed. Changes in the microstructure and the mechanical properties of nanostructured nickel produced by torsion under quasi-hydrostatic pressure and equal-channel angular pressing are experimentally studied. It has been shown that, at some moderate values of the amplitude, the ultrasonic effect leads to a decrease in internal stresses, as well as an increase in the thermal stability of the structure and the ductility of the nanomaterials.
10 citations
TL;DR: In this article, the impact of soils on the subsurface level is considered and blocked cutting is performed without carrying of soil particles over the ground surface, where the soil, condensed around the chisel of the tool due to air and the impact supersonic waves, are formed and propagated at an angle of the natural slope.
Abstract: Blocked cutting takes place at the impact of soils on the subsurface level — without carrying of soil particles over the ground surface. Lumps of soil, condensed around the chisel of the tool due to air (elasticity modulus increases up to 40 MPa) and the impact supersonic waves, are formed and propagated at an angle of the natural slope (≈45°) and decompress the soil.
9 citations
TL;DR: In this article, it is shown that the composition and structure of diamond-like carbon coatings deposited on friction surfaces of steel parts of lubricated friction units have a substantial effect on the degree of the orientation of molecules of a lubricant in a boundary film and, therefore, on the antifriction behavior of the lubricant under boundary lubrication conditions.
Abstract: It is shown that the composition and structure of diamond-like carbon coatings deposited on friction surfaces of steel parts of lubricated friction units have a substantial effect on the degree of the orientation of molecules of a lubricant in a boundary film and, therefore, on the antifriction behavior of the lubricant under boundary lubrication conditions. We present the results of research carried out in recent years at the Department of Friction, Wear, and Lubrication of the Blagonravov Institute of Machine Science of the Russian Academy of Sciences in collaboration with the Chemical Faculty of the Lomonosov Moscow State University and the 25th State Research Institute of the Ministry of Defense of the Russian Federation in order to enhance the lubricity of oils, as well as to simplify and cheapen their compositions, which is of great importance from the viewpoint of ecology.
TL;DR: In this paper, two mathematical models for determining the dynamic accuracy of manipulation systems of robots with elastic hinges are considered and the results of modeling the dynamics by two models are compared to the example of a three-link manipulation system.
Abstract: Two mathematical models for determining the dynamic accuracy of manipulation systems of robots with elastic hinges are considered. Mathematical models are the implementation of the method based on the Lagrange equation and using the transformation matrices of elastic coordinates. Mathematical models make it possible to determine the elastic deviations of manipulation systems of robots from programmed motion trajectories caused by elastic deformations in hinges, which are taken into account in directions of change of the corresponding generalized coordinates. One model is the exact implementation of the Lagrange method and makes it possible to determine the total elastic deviation of the manipulation system from the programmed motion trajectory. Another mathematical model is approximated and makes it possible to determine small elastic quasi-static deviations and elastic vibrations. The results of modeling the dynamics by two models are compared to the example of a three-link manipulation system. The considered models can be used when performing investigations of the mathematical accuracy of the manipulation systems of robots.
TL;DR: In this paper, deterministic and probabilistic estimates of strength are compared for the cases of serial loading based on the results of the use of the extreme value theory, and the need to clarify the traditional estimates obtained under the assumption of one-time loading is substantiated.
Abstract: In this paper, deterministic and probabilistic estimates of strength are compared for the cases of serial loading based on the results of the use of the extreme value theory. The need to clarify the traditional estimates obtained under the assumption of one-time loading is substantiated.
TL;DR: The article is devoted to the synthesis and analysis of new scheme, being the development of the well-known “ORTHOGLIDE” robot device, which is a scheme for manipulating mechanisms of parallel structure with four, five and six degrees of freedom when rotation is transferred by the same kinematic chain which provides the progressive motion.
Abstract: The article is devoted to the synthesis and analysis of new scheme, being the development of the well-known “ORTHOGLIDE” robot device, which is a scheme for manipulating mechanisms of parallel structure with four, five and six degrees of freedom when rotation is transferred by the same kinematic chain which provides the progressive motion.
TL;DR: In this article, a model of deep drawing of a thin-walled hemisphere with a flat bottom from a plane blank by a rigid punch, considering the work hardening and wall thickness variation is developed.
Abstract: A model of deep drawing of a thin-walled hemisphere with a flat bottom from a plane blank by a rigid punch, considering the work hardening and wall thickness variation is developed. Elastic bending and von Mises membrane rigid-plastic strain with different friction coefficients at the punch and die contact boundaries are considered. The computational model determines the distribution of the wall thickness and the material work hardening along the shell generatrix, the drawing force versus punch displacement relation, and the critical parameters of the process in which some defects are probable.
TL;DR: In this article, the authors developed and validated refined calculation methods for durability and survivability at the design stage and at the stage of operation of products under extreme loading conditions (large variable loads, high temperatures, vibration feedback).
Abstract: Improving the strength and reliability of machine parts and structures requires the development and validation of refined calculation methods for durability and survivability at the design stage and at the stage of operation of products under extreme loading conditions (large variable loads, high temperatures, vibration feedback). The establishment of such methods requires research in behavior of structural materials and coatings based on experimental studies in conditions close to operational loadings.
TL;DR: In this paper, an active double loop reversible temperature control system based on thermoelectric Peltier modules for controlling temperature fields of individual fiber optic inertial sensors, and the strapdown inertial navigation system containing these sensors, are constructed and investigated.
Abstract: Mathematical models of an active double loop reversible temperature control system based on thermoelectric Peltier modules for controlling temperature fields of individual fiber optic inertial sensors, and the strapdown inertial navigation system containing these sensors, are constructed and investigated. The supporting software is developed. Parameters of the temperature control system are selected. The performance of dynamic systems under severe temperature conditions is evaluated.
TL;DR: In this article, the properties of heat-resistant steels are improved by the use of the new complex technology of thermal and chemical-thermal treatment based on the formation of a finely dispersed structure during hot deformation and activation of diffusion saturation during ion-plasma nitriding.
Abstract: Values of hardness, wear resistance, and contact endurance limits for steels VKS-7 and VKS-10 found experimentally in various test conditions are presented. Characteristics of mechanical properties of heat-resistant steels are improved by the use of the new complex technology of thermal and chemical-thermal treatment based on the formation of a finely dispersed structure during hot deformation and activation of diffusion saturation during ion-plasma nitriding.
TL;DR: In this article, a comparison of results of measuring residual stresses and with the study of their effect on the fatigue strength of parts of gas-turbine engines after finish treatments by grinding, polishing, and surface plastic deformation is presented.
Abstract: The paper deals with a comparison of results of measuring residual stresses and with the study of their effect on the fatigue strength of parts of gas-turbine engines after finish treatments by grinding, polishing, and surface plastic deformation.
TL;DR: In this paper, a formula for calculating inspection times of monitoring the technical condition of a hazardous industrial facility, as well as the number of operation intervals between monitoring events depending on certain values of parameters of reliability of the facility were demonstrated.
Abstract: A formula for calculation of inspection times of monitoring the technical condition of a hazardous industrial facility, as well as a formula for calculation of the number of operation intervals between monitoring events depending on certain values of parameters of reliability of the facility were demonstrated. In addition, the monotonic behavior of the duration of equally possible operational intervals between monitoring events for facilities with monotonic changes in fault occurrence intensity was defined. A monotonic behavior in values of probabilities of flawless performance of the facility within intervals between monitoring events with equal duration of operation and monotonic change in intensity of faults occurrence were demonstrated.
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TL;DR: In this article, a wave hydro massager was developed and experimentally examined and the maximum oscillation amplitude was observed in the frequency range 88-504 Hz depending on the circulation of the water supply and pressure at the inlet to the massager being 0.2-0.6 MPa higher than atmosphere pressure.
Abstract: Wave hydro massagers, differing from similar devices by vacuum pressing action on the human skin, are developed and experimentally examined. The vacuum level created in different operational conditions is 1–9 kPa. The maximum oscillation amplitude is observed in the frequency range 88–504 Hz depending on the circulation of the water supply and pressure at the inlet to the hydro massager being 0.2–0.6 MPa higher than atmosphere pressure. The area of application of these devices is therapeutic massage given both in clinical and home conditions.
TL;DR: In this paper, the reliability of rapidly worn parts of technical fleet vessels is considered and Recommendations for improving their durability are given, based on which the problems of the reliability and reliability of quickly worn parts are considered.
Abstract: The problems of the reliability of rapidly worn parts of technical fleet vessels are considered. Recommendations for improving their durability are given.
TL;DR: In this paper, the authors describe a type of problem with a periodic distribution of stresses outside round holes and cracks for lateral shear, and the solution to the problem is reduced to solution of two nonlinear singular integral equations.
Abstract: Elastic media (a plane) weakened with a periodic system of round holes filled with plugs made of homogenous elastic material with the surface was covered by a homogenous cylindrical film. The plane is weakened by two periodic systems of straight line cracks with connections between edges at the tip regions. General concepts describing a type of problem with a periodic distribution of stresses outside round holes and cracks for lateral shear are proposed. The solution to the problem is reduced to solution of two nonlinear singular integral equations. The solution of these two equations define forces in relation to the tip regions. The condition for the propagation of a crack is formed considering criteria for the limiting shear of bonds inside the material.
TL;DR: In this article, a mathematical model of the inner step thread with an abrasive wheel without tilt of the tool spindle is described, and the problem of calculation of a shape of a curvilinear part of the profile of the grinding wheel and simulation of thread processing is solved for the evaluation of a possibility of cutting this thread with the required accuracy using a tool of a certain diameter.
Abstract: A mathematical model of the grinding process for an inner step thread with an abrasive wheel without tilt of the tool spindle is described. The problem of calculation of a shape of a curvilinear part of the profile of the grinding wheel and simulation of thread processing is solved for the evaluation of a possibility of cutting this thread with the required accuracy using a tool of a certain diameter. Examples of calculation of the process parameters for grinding various types of inner thread are shown.
TL;DR: In this article, an experimental investigation of the mechanical behavior of carbon fiber-reinforced plastic laminates under quasistatic and cyclic loading is performed, where a uniform nonlinear elastic deformation of carbon fibre reinforced plastic Laminates with uniform increment of the tangent modulus is studied.
Abstract: An experimental investigation of the mechanical behavior of carbon fiber-reinforced plastic laminates under quasistatic and cyclic loading is performed. A uniform nonlinear elastic deformation of carbon fiber reinforced plastic laminates with uniform increment of the tangent modulus is studied. A condition for the initiation of the microscopic damage process was identified. The analysis of discreet continuous stages of the damage process followed by energy release was conducted. A diagram of deformation up to full loss of carrying capacity of the material is plotted. The proposed approach can be useful for diagnostics of elements of composite structures in operation.
TL;DR: In this article, the contact interaction between a rigid sphere and a two-layered elastoplastic half-space (topocomposite) which imitates a surface hardened with the thin protective coating has been studied.
Abstract: The mechanics of contact interaction between a rigid sphere and a two-layered elastoplastic half-space (topocomposite) which imitates a surface hardened with the thin protective coating has been studied. The behavior of contact parameters of the deformation force, as well as its effective characteristics (load-carrying ability, yield point and compositional hardness) against the cost of the deformational hardening of the layered body base material has been investigated.
TL;DR: In this article, a method for Fourier series expansion was developed to describe strongly localized mechanical loads that can affect thin-walled shell structures in the form of bodies of revolution.
Abstract: A method for Fourier series expansion is developed to describe strongly localized mechanical loads that can affect thin-walled shell structures in the form of bodies of revolution. The results of calculations for shells loaded by local loads of various types are reported. The results of calculation of the stressed state using the Fourier series are compared with those obtained by the finite element method.
TL;DR: In this paper, a method of determination of the service life of the instrument for cold sheet s is developed based on correlation between the magnetic, mechanical and physical-chemical (chemical composition, thermal processing mode, plastic deformation, micro- and macrostress, positioning of dislocations, etc.) properties of the die tool materials.
Abstract: Based on the representative sampling of experimental data and processing of the obtained results, a method of determination of the service life of the instrument for cold sheet s is developed. The method is based on correlation between the magnetic, mechanical and physical-chemical (chemical composition, thermal processing mode, plastic deformation, micro- and macrostress, positioning of dislocations, etc.) properties of the die tool materials.
TL;DR: In this paper, the authors compared the results of measurements of residual stresses and study the influence of residual stress on the fatigue strength of samples made of titanium and nickel alloys after various types of treatment: turning with the use of various lubricating cooling tools, grinding, and surface plastic strain operation.
Abstract: In this paper, we compare the results of measurements of residual stresses and study the influence of residual stresses on the fatigue strength of samples made of titanium and nickel alloys after various types of treatment: turning with the use of various lubricating-cooling tools, grinding, and surface plastic strain operation.
TL;DR: In this article, a method for estimating the strength of structural elements made of composite materials with a thermosetting matrix, which was characterized by the presence of exfoliation-like defects and process-induced deformations, was proposed.
Abstract: A method for estimating the strength of structural elements made of composite materials with a thermosetting matrix, which was characterized by the presence of exfoliation-like defects and process-induced deformations, was proposed. In order to determine the process-induced deformations, a mathematical model, which considered thermal and chemical deformations, heat release in the course of matrix polymerization, as well as changes in the matrix properties in transition from the superelastic to the solid state, was implemented. A modeling of the deformation of a standard blank with an interstitial exfoliation-like defect was carried out. A quantitative defect of the effect of the process-induced deformations and the initial dimensions of the defects on the load at which the defect begins to grow was made.