Vol 37, No 2 (2017)

The improvement of energy-saving modular electric furnaces for the thermal activation of minerals is considered. It is expedient to introduce a nonelectrified roasting module based on secondary energy resources so as to complete the dehydration and expansion of vermiculite and/or the thermal activation of sungulite–vermiculite conglomerates.

The spectral characteristics of hydraulic bearings and cable-based dampers are presented. In hydraulic bearings, the energy is absorbed by a rheological medium; in cable-based vibrational dampers, by contrast, the energy is absorbed by the dry friction of individual elastic wires within the strands of a steel cable system. In both cases, the experimental conditions are exactly the same. With the same spectra of the input vibrations, the output spectra are found to be considerably different.

A formula is derived for calculating the interaction forces of the bristles of an abrasive polymer brush and the edge being machined.

A method is proposed for calculating the cutting characteristics in the end milling of stainless steel workpieces. The calculation is based on analysis of the parameters for the chip-formation zone and takes account of softening of the material under the action of the cutting temperature. The calculated tool life and the torque are approximated by polynomial equations, which may be used to calculate the constraints on milling and to optimize the machining conditions.

By modernizing outdated machine tools for specific functions on modular principles, manufacturing and, in particular, metalworking may be brought to current standards without huge capital expenditures. As an example, the modernization of the 6М610F11-23 longitudinal milling machine and its utilization in the manufacturing of inexpensive molds offers a valuable means of import substitution for RUSAL.

The creation of a hard-alloy metal-cutting tool for the finishing of materials that are hard to machine is considered. To improve the machining quality and productivity, the use of a tool with 1-μm sharpness is proposed.

The boundary conditions in the contact of an abrasive wheel with a rubber coating and also in the contact of a single grain with rubber are investigated. The influence of the grain geometry of the normal and tangential stress in the contact zone with the rubber is analyzed. By numerical simulation of the work of a single grain, contact-stress curves may be plotted for the machining zone. An analytical formula is derived for the machining force when the wheel is held steadily against the workpiece.

A new approach is proposed to the design of grinding operations in multiproduct manufacturing. The method is based on predicting the capabilities of abrasive tools and making full use of their capabilities. That permits more efficient utilization of abrasive tools over a broad range of operating conditions and improves the machining efficiency, which is of great importance in multiproduct manufacturing.