卷 37, 编号 9 (2017)

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.

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.

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.

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.

An improved method is proposed for assessing cutter wear in the certification of rock-breaking tools.

The formulation of adequate requirements in manufacturing is outlined on the basis of structure–strategy theory.

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).

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.

Parameter specification in the trochoidal machining of a slot of constant width is considered. A formula is proposed for the displacement increment of the shaping circle as a function of the cutting depth.

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.

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.