


Том 37, № 9 (2017)
- Год: 2017
- Статей: 22
- URL: https://journal-vniispk.ru/1068-798X/issue/view/14013
Article



Active low-frequency vibrational-isolation system with compensation of dynamic forces
Аннотация
The feasibility of an active low-frequency vibrational-isolation system with compensation of the dynamic forces on the housing by means of antiphase inertial forces is considered. This system effectively reduces the forces transmitted to the housing from vibrations of an elastically suspended mass in the low-frequency subresonance range.



Optimizing the configuration of transport and storage systems
Аннотация
A method is proposed for selecting the configuration of transport and storage systems. The method permits optimization of the configuration of transport hubs and storage systems so as to facilitate loading, unloading, storage, and handling of loads, with minimal capital and operating costs.



Laser modification of frictional surfaces
Аннотация
Improvement in the physicomechanical properties and frictional characteristics of cylinder and piston surfaces in airplane internal-combustion engines is considered. A method of developing recommendations regarding the optimization of laser treatment is proposed on the basis of experiments and a model of surface wear.



Control of lubricant performance
Аннотация
Multifunctional optimization of the content of three-component lubricant (bitumen + stearic acid + foam glass) with respect to three criteria is based on experimental data. The three criteria are the frictional coefficient, the wear rate of the wheel rim, and the lubricant consumption.



Diagnostics of low-temperature structural stability
Аннотация
The failure of materials at low temperatures is studied. The acoustic signals emitted in the extension of steel 45 at low temperature are analyzed. In this conditions, the yield point and strength increase, while the relative elongation declines.



Improving the wear resistance of machine parts
Аннотация
Various types of operational faults in critical machine parts are analyzed. The possibility of eliminating the factors responsible for such faults at the manufacturing stage is considered. Thermodynamic analysis reveals the relation between the bulk wear rate and the surface quality.



Self-balancing high-speed mill
Аннотация
A long milling tool with a hollow shank is considered. A special chamber in the shank accommodates the compensation material. This design ensures that the tool is self-balancing. That reduces its vibrational amplitude and increases the productivity in high-speed machining.









Surface restoration and reinforcement
Аннотация
The carrying capacity of prestressed joints may be increased by plastic deformation of one surface using a flexible tool (rotating wire brush) and simultaneous coating application to that surface. An aluminum coating increases the frictional coefficient in the joint. Impact-friction treatment or dynamic cold working by hammer faces creates a strengthened nanostructured layer.









Reamers with composite 01 cutters
Аннотация
The design of expanding reamers with composite 01 cutting plates (based on boron nitride) is outlined. The geometric parameters required for the design documentation are presented for the internal machining of hydraulic cylinders (diameter 25–250 mm).



Single-turn worm mills for conical round-tooth gears
Аннотация
Facets must be machined at the end of gear teeth. The shaping of facets by single-turn worm mills is considered in detail. Deficiencies are found in familiar design methods for such mills. Formulas are proposed for the calculation of single-turn worm mills used in machining conical round-tooth gears.



Active adaptation in robotic assembly
Аннотация
A two-point contact model in robotic assembly is considered, in a quasi-static formulation. In the experiments, a robot equipped with a force and torque sensor is employed. The consistency of theoretical analysis with physical experiments is discussed.









Errors in shaping by a planetary mechanism
Аннотация
The proposed planetary reaming method permits discontinuous turning in which the cutting edge moves relative to the cutting surfaces. As a result, individual sections of the cutting zone move successfully in and out of the machining zone. Discontinuous turning is free of the deficiencies of continuous turning.



Energy planning in production shops with numerically controlled machine tools
Аннотация
A method is proposed for planning the energy expenditures in production buildings with numerically controlled machine tools. The calculations take account of the individual production operations, as well as the actual state of the machine-tool drives.



Standardization of terminology in the kinematics of cutting and surface shaping
Аннотация
New definitions are proposed for some terms in State Standard GOST 25762–83. Additional terms and definitions are proposed to describe surface shaping by cutting tools. The new terms eliminate some omissions in our general concepts regarding the kinematics of cutting and surface shaping.



Automated instrument for assessing abrasives
Аннотация
An automated instrument for monitoring the destructive compressive load on abrasive grains (measuring 400–1250 μm) between two rotating rollers has been developed. A modernized version of the instrument also permits determination of the grain size, shape, and microgeometric and topographic characteristics of abrasives. Equipped with a photometric unit and a module for processing numerical information, the modernized instrument permits multiple recording of each particle by six cameras (in both directions along three orthogonal axes), with assessment of the microgeometry. Such information regarding the grains, along with identification of their shape (plates, needles, isometric form, etc.), permits their quality assessment; their subsequent separation on vibrational sorters; and their most effective use in the abrasive machining of materials characterized by different hardness, brittleness, and composition, including composites.


