Vol 36, No 6 (2016)

A structural–parametric model of a piezo motor is formulated by solving the wave equation. The influence of geometric and physical parameters and external loads on its static and dynamic characteristics in the control system is studied. Transfer functions are derived for piezo motors used in nanodrives. The parametric structure of the piezo motor is determined and transformed.

The potential of acoustic tensometry in monitoring the nonplanarity of circular wood saws is considered. A suitable monitoring parameter is identified, and zones with the maximum residual stress are found. These results are recommended for use in monitoring nonplanarity.

Express monitoring of the strength of bolts is considered. In the proposed method, a spherical indenter is introduced in the material, the diameter of the residual impression is measured, and the plastic hardness is determined from the contact hardening module of the material.

The expansion of shaped pipe in oilfield borehole repair by means of various shaped draw bars is modeled by the finite-element method. The optimal draw-bar configuration is determined from the pressure on the tool and the effective strain. Recommendations are made regarding the shape of the draw bar.

The wear of a diamond tool in the dressing of continuous and discrete grinding wheels is studied. Formulas are derived for the wear of the diamond grains and the dressing tool when applied to a wheel with a discrete cutting surface.

Analytical formulas are derived for the internal surface characteristics of a large cylindrical workpiece after treatment by an abrasive–air jet as a function of the machining conditions. A formula for the productivity is also presented.

An automated information system is developed for the design of model sets required in the manufacture of large structural castings that may be used in the basic components of mechatronic machine tools. The analysis is based on 3D geometric modeling by means of the API function in the CAD system. The results permit the automated design and subsequent manufacture of model sets for numerically controlled machine tools.

This review covers the current state and prospects for the design of metal-cutting machines, including numerically controlled machines. The characteristics of common mechatronic modules are considered. The structure of metal-cutting machines is outlined, and means of complying with operational requirements are presented.

Besides traditional cutting tools, rotary tools are now being used. In view of their benefits, further research is advisable, with a view to their widespread use — in particular, in the machining of complex surfaces. The possibility of producing a helical profile by means of rotary tools in a traditional cutting configuration is mathematically established, with slip of the chip over the face (beginning at the larger diameter of a tapered tool).

Known criteria for the optimization of cutting processes are appraised. A new criterion for determining the optimal conditions in metal cutting is proposed.