Questions are considered for improving the efficiency of press-fitting rolling cutter bit teeth based on using high-frequency low-amplitude ultrasonic vibrations that intensify the assembly processes. A computer automated system is developed for scientific studies of the process of ultrasonic assembly (ultrasonic press-fitting) of hard alloy bits with simultaneous diagnosis of quality indices for the joint formed. Experimental studies are performed for the press-fitting force and strength properties of joints assembled by traditional methods and with the action of ultrasound that have shown a reduction in press-fitting force by up to 20% with a simultaneous increase in strength by 5%.Premature failure of drill bits and the existence of a reduction in drilling efficiency occurs due to crack formation within the body of a rolling cutter, in rings and the inter-ring space in zones of press-fitting teeth into a hole, particularly in rolling cutters of small diameter. Microcracks, that arise during tooth compaction are transformed into macrocracks with hundreds of thousands of loading-unloading cycles with loads from zero to the maximum during action of teeth on rock which leads to rolling cutter breakage and accidents during boring.Contact bonds that form during tooth compaction govern, on one hand, the force and accuracy parameters of the production process itself for joining components and, on the other hand, operating indices of the assembled rolling cutters. Control of assembly and engineering monitoring of the joints formed is traditionally accomplished by measurement of forces and moments applied to a component, and their coordinates with respect to the relative movement of teeth during press-fitting.The main complication in organizing management of press-fitting is connected with production and assembly errors that relate to deviations of dimensions, shape and surface roughness for assembled components, inaccuracy of the reciprocal position of assemblies with units for assembly position, disturbance of assembly conditions, inaccuracy in functioning of assembly equipment, etc. In Volgaburmash and SamGTU, research work has been carried for determining the optimum parameters for locating teeth in rolling cutter rings, and finite element methods have been developed making it possible to

The article proposes a new approach to the method of assessing the surface defects of the raceway of instrument bearings after profile grinding. The surface defects of the bearing raceways were studied on an optical-electronic complex on the basis of calculating the parameters of the autocorrelation function obtained as a result of computer processing of the video image of the surface. The purpose of this study is improving the profile grinding technology of bearings through the construction of an optical-electronic information-measuring system for monitoring the defects of raceways.

The paper proposes a model of an equal-wear shape of the working surface of grinding wheels operating in the self-sharpening mode, where the principles of system workability are used. It is established that to obtain engineering solutions, the wheel should be considered as a ceramic body that cuts into the ‘Voicht medium’. A disadvantage of the adopted model is that it does not consider the lag caused by strain. In addition, when grinding, the process temperature and the deformation rate are significantly higher than when the machine parts rub together. It is shown that the condition of equal wear of the wheel surface is provided by equal wear of the abrasive grains on the entire working surface, the density of the working grains on the elementary section of the contact surface. The paper presents conditions under which equal-wear shapes of wheels working with a longitudinal feed are provided.

This paper presents the results of our research into improving the design and fabrication quality of custom-molded corrective insoles by developing modern computer-aided modeling and programming methods that factor in changes in the mechanical properties of materials during use. This paper proposes a method for designing custom corrective insoles using the optimal insole structure and material. We used OrthoModel to design an insole model in a solid-body format and then exported it as an STL file. Then, using FreeCAD, we converted the STL file to a STEP file to better adapt the model for further use and analysis. Using the Ansys environment, we devised a finite element model for insole deformation and investigated the behavior exhibited by the material of the insole arch under different loads and combinations of EVA materials with varying hardness. The model yielded the stresses and deformations experienced by the insole arch during use, depending on the combination of the material and the geometry of the foot, and those stresses and deformations were experimentally verified. The calculated values for insole deformation served as input for programming the processing of the insole with a CNC machine. With a 3D insole model, it is possible to both fabricate the insole with a CNC machine and to print the insole with a 3D printer. The calculated cost price of fabricating custom-molded corrective insoles attests to the competitiveness of the proposed technique.

To restore the shape of curved low-stiff cylindrical parts such as shafts and axles, the process of straightening by transverse bending is considered with subsequent hardening by the method of surface plastic deformation based on the transverse rolling of the cylindrical part with flat plates. The stress states of parts during editing are determined using the Ansys Workbench software package. The results of the distribution of the intensity of operating voltages and residual stresses over the cross section of the cylinder, depending on the absolute compression, are presented. The process in question can be implemented without the use of environmentally hazardous lubricating cooling technological means, which makes it possible to attribute it in the future to one of the types of green mechanical processing technologies.