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卷 39, 编号 8 (2019)
- 年: 2019
- 文章: 21
- URL: https://journals.rcsi.science/1068-798X/issue/view/14043
Article
Selecting the Gear Ratio of the Final Drive in Light Caterpillar Vehicles
摘要
Analysis of kinematic systems, final-drive designs, and the characteristics of the components permits the development of a method of selecting the gear ratio of the final drive and computer calculation of the strength of its components in a light caterpillar vehicle as a function of the gear ratio of the final drive and the speed of its components. A method is developed for assessing the calculations in terms of the basic strength parameters, so as to ensure rapid calculations with changes in the components, materials, speeds, and loads.
631-636
CNC Machine Tools and Digital Twins
摘要
Neural-network models used in the development of digital twins for production equipment are considered. Such a model of the dynamic stability of cutting is assessed. A spectrogram showing the vibrational amplitude and frequency of the elastic system in a CNC machine tool is presented. The fractional dimensionality of the corresponding attractors is determined.
637-644
Shaping of Cams for High-Torque Variable-Speed Drives
摘要
Attention focuses on the calculation of the working profile for three-dimensional cams in an oscillatory lever mechanism with a contacting spherical roller. That permits the creation of 3D surfaces for milling of the cams on CNC machine tools. Methods are proposed for determining the pressure angle and selecting the optimal parameters of the oscillatory mechanism in a nonfrictional high-torque variable-speed drive.
645-649
Hydrodynamic Calculation of a Thrust Bearing with an Adapted Profile
摘要
Hydrodynamic models are considered for thrust bearings with a profile adapted to the frictional conditions, when operating in incompressible electrically conducting lubricant. The basic operational characteristics of a bearing, with deformation of the frictional pair’s supporting system, are derived on the basis of the equation of motion of the material in the working gap, the continuity equation, and the Darcy and Lamé equations for a thin layer.
650-655
Production of Large Disks from Cylindrical Blanks by Plastic Deformation. 3. Final Stage of Central-Punch Introduction
摘要
Abstract—The final stage of central-punch introduction during the plastic deformation of large disks or hard-to-deform disks is mathematically described. The maximum force of punch introduction at the end of deformation is determined
656-658
Residual Stress in the Surface Layer after Asymmetric Lapping
摘要
Abstract—The influence of asymmetric uninterrupted lapping on the residual stress in the surface layer of the workpiece is investigated, with a view to increasing product strength.
659-664
Dual-Action Drilling and Milling Tool
摘要
Abstract—Analysis of drilling methods and drilling tools used in the oil and gas industry gives rise to a new dual-action drilling and milling tool, which ensures constant contact of the tool’s cutting edge with the face. That reduces the frictional forces in drilling and improves the tool’s wear resistance.
665-668
Smart Automated Design Utilizing Engineering Experience
摘要
669-671
Additive Technology in Restoring the Worn Spherical Surface of Crusher Cones
摘要
Abstract—Restoration of the spherical surface of a steel 35L cone housing by mechanized surfacing in protective gas is proposed. The method employed does not involve heating of the part before or in the course of surfacing. The coating produced has the required thickness and chemical composition, with specified structure. The coating is strongly bound to the restored surface and is free of pores and cracks.
672-679
Informational Model of State Change in a Mechanical System
摘要
The use of information theory to formulate an informational model of the change in state of mechanical systems is considered. By that means, models of the change in state of system components may be developed for different operating conditions. In regions of the system’s state space corresponding to critical values, the probability of a fault may be determined.
680-682
Assessing the State of Mechanical Systems of Different Complexity
摘要
Abstract—The use of information theory to assess the state of mechanical systems of different complexity is considered.
683-685
Electromechanical Converters in Guaranteed Power-Supply Systems for Drives of Machine Tools and Manufacturing Equipment
摘要
686-688
Drives in Systems Based on a Composite Electrical Machine with a Circular Field in the Air Gap
摘要
689-692
Production of Tool Coatings by Chemicothermal Plasma Methods
摘要
Abstract—Two methods are considered for the production of wear-resistant coatings for cutting and stamping tools: plasma nitriding with subsequent oxidation; and plasma chemical vapor deposition of metals with preliminary nitriding. The microstructure of the modified layers, their microhardness, and the tool life are discussed.
693-695
Influence of Nitriding on the Wear Resistance and Adhesion of Zinc Coatings on Steel
摘要
Chemicothermal treatment of steel is considered: specifically, diffusional zinc coating in a nitrogen-bearing medium; and nitriding of a preformed zinc-filled coating. The structure of the modified layers is investigated. Their microhardness and wear resistance increase as a result of solid-solution hardening by zinc and nitrogen.
696-698
Improvement in Ultrasound Liquid Machining by Activating Cavitational Clusters
摘要
In the erosion-free zone that appears during high-amplitude ultrasound treatment, the useful work is mainly performed by cavitational clusters. In the absence of collapse, the clusters grow and produce small-scale turbulence. As shown in the present work, cavitational clusters may be activated by the additional acoustic pressure arising when a low-amplitude source is coaxial with the high-amplitude source.
699-702
Improving Rivet Performance by Ultrasonic Shock Treatment
摘要
The reliability of rivets is improved if the residual compressive stress is uniformly distributed over the joint thickness, with simultaneous decrease in the riveting forces required. The possibility of improving rivet performance by ultrasonic shock treatment is considered. On that basis, a riveting method is proposed. Its effectiveness is analyzed.
703-704
Life-Cycle Approaches in Computerized Vehicle Design and Additive Technology
摘要
Computer engineering permits the creation of models closely matching actual processes and vehicle designs. Production costs may be significantly reduced, while additive technologies permit customized production, with minimal expenditure of time and materials in development and prototyping. Such technologies may expediently be used in digital design of vehicles, taking account of the complete product life cycle.
705-709
Additive Technology in Optimal Synthesis of Individual Vehicle Components and Mechanisms
摘要
Experience in optimal synthesis of individual vehicle components and mechanisms on the basis of additive technology is analyzed. A list of basic additive technologies is presented. The benefits of additive technology in combination with three-dimensional computer simulation are noted. The possibility of visualizing CAE calculations by means of additive technology is considered. In addition, the role of additive technology in the manufacture of individual vehicle components and mechanisms is discussed.
710-712
Conversion of Diesel Engines to a Gas and Gas–Diesel Cycle
摘要
The conversion of diesel engines to gas and gas–diesel cycles during the production process is analyzed. The requirements for conversion to natural-gas operation are presented. The power, efficiency, and environmental impact of diesel engines, natural-gas engines, and gas–diesel engines are compared.
713-716
Improving the Components of a High-Pressure Hydraulic System in a Piston Power Unit
摘要
Abstract—The influence of fuel-injector manufacture on the hydraulic characteristics of a piston power unit is explored. The existing fuel system for diesel engines is better suited to stable operation with no load, despite the losses associated with wear of its components and incorrect tolerances and gaps.
717-720