Vol 22, No 3 (2020)

In this article, we present the results of analysis of dimensional links in a structure of a rotary-dividing table. We show that dimensional links have a bearing on indicators of geometric accuracy. It is revealed that the dimensional chains which describe a process of forming accuracy indicators are related. It is established that some components of the dimensional chain change their direction in the process of achieving accuracy. In order to decrease alabour input of assembly some proposals based on the result of calculationare developed.

The analysis method cyclic error of working of hole after centrifugal honing operation are stated.

The methodology and results of calculating the residual stresses in thin surface layers of bearing rings with an arbitrary cross section after finishing abrasive and various methods of surface hardening of raceways are described. The calculation results were verified by modeling the process of formation of residual stresses caused by thermal deformations during circular mortise grinding of rings.

The article prezents the results of researches carried out to develop the design of drilling rock bin of small diameter, intended for drilling of additional sidetracks of horizontal wells. Recommendations on the development of fundamentally new bits.

The article presents the results of the study of technical and economic performance indicators of restored MNP in the processing of steels. As an assessment of the performance of the cutting edge of the plate, two evaluation criteria were taken: the rate of loss of the value of the face Km in € / cm3 and the cost of removing 1 m3 of chips S (1m3) in € during finishing and rough turning. The technique of obtaining the maximum performance of the process at the minimum cost of recovered plates is developed. Comparative tests of purchased and restored products in experimental and industrial conditions were carried out. As a result of the conducted experimental researches it is established that at final turning loss of cost of a face of a plate Km is 3-4 times lower at the restored plates , than at purchased. When working on rough modes restored plates criterion Km in 2-2. 5 times less.

The technique choice of a method installation work piece of taper roller when grinding its spherical ends.

The article presents the results of the development of technology recovery MNEs. The problem statement is connected with increase of durability, firmness and operational properties of MNP. The technology of plate recovery provides: development of technological scheme of MNP flow over the front surface and application of wear-resistant coatings from TiN. The optimal geometry of the restored tool, the sharpening scheme is determined, the characteristics of grinding wheels and cutting modes are selected. The technology of coating, scheme and modes of surface cleaning are developed, the parameters of coating quality are determined.

The article presents the results of research on the elimination of defects from bronze using electric welding and soldering in the central lithium technologies of SamSTU. The influence of the type and quality of welding on bronzes has been experimentally investigated. Based on the studies, the optimal modes of welding and soldering of defects from bronze were determined.

The article is the first to analyze the installation process of automotive glass, taking into account geometry deviations and the resulting unevenness of the formation of a gap around the glass perimeter during assembly. Based on the simulation of the assembly process using CAD / CAE, the formation of residual stresses in the glass is shown, the results are obtained, based on which conclusions can be drawn about the effect of geometry accuracy on the strength of the glass.

The article investigated the dependence of cutting conditions on the temperature of the cylinder liner during the boring process. A series of experiments were carried out to determine the temperature and sharpness forces during mechanical processing. The influence of cutting conditions (cutting speed, feed, cutting depth) and sharpness and temperature during machining, as well as thermal expansion of workpieces under different thread conditions (especially when high-speed cutting with a cutting frequency of up to 850 m / min) were investigated.

Examined the movement of microparticles in the air flow aimed at a flat shielding surface. The structure of the unsinkable jet has been refined, the core of the jet with its geometric, kinetic and dynamic parameters, reproduced on the treated surface, has been highlighted.

Studies were carried out to identify the relationship between the intensity of adhesion of the workpiece material particles on abrasive grains (AZ) of the grinding wheel with the physical and mechanical properties of the grains. The mathematical dependence for the calculation of the voltage at the contact area of the clip with AZ after the AU out of contact with the workpiece is obtained. Numerical simulation of local temperature when microreserve (scratching) samples of steel 3KH3M3F abrasive grains of various materials. The deformation of the adhesion and the stresses resulting from this deformation acting on the connection of the adhesion with grains from materials having different coefficients of linear expansion are calculated. It is established that with the increase of the difference of coefficients of linear expansion of the workpiece materials and AZ, the stresses contributing to the separation of the adhesion from the AZ surface increase. This makes it possible to predict a lower intensity of sticking of the workpiece material on the AZ of such materials. In the course of experimental studies, micro-cutting of samples by single abrasive grains was carried out. It was found that to a lesser extent wear out and salted AZ from elbor. Elbor has the maximum value of the coefficient of thermal conductivity among the tested materials and to a lesser extent wears out, so the local temperatures when cutting grains from Elbor are minimal. The difference between the coefficients of linear expansion of the material adhesion and elbor has a maximum value. Therefore, the contact area of AZ CBN with adhesion there is tension, contributing to the separation adhesion from this surface. As a result, AZ was ranked from various materials according to the criteria characterizing their wear and salting. Confirmed identified analytically the relationship between the intensity of brining of grain with a coefficient of linear expansion and thermal characteristics of the materials AZ.

Expound variation of models forming shape, their essence and protocols applicability in analysis true turning operations.

The article discusses the deformation of plates and shallow shells, taking into account the geometric nonlinearity and plastic deformations under variable loading. In the case of an elastoplastic material, unloading, secondary plastic deformations, material compressibility are taken into account. Geometric and physical relations and solving nonlinear differential equations of the theory of flexible gentle shells of elastoplastic material are given for an arbitrary loading cycle. The relationship between the intensity of stresses and strains, using the generalized Mazing principle, allows us to investigate the deformation of flexible plates and shells of cyclically ideal, strengthened and softened materials. In the expressions for the internal forces and internal moments, additional forces and additional moments are taken into account, taking into account the history of loading of plates and shells on the previous n-1-th loading.