Journal of Machinery Manufacture and Reliability最新文献

This study addresses the practical application of the digital image correlation method for experimental investigation of significantly inhomogeneous residual stress fields using the “large hole” drilling technique. Specially designed polymer material samples were used, in which a high-gradient residual stress field was created based on the approach proposed by the authors. Recommendations for optimal relationships between the diameter of the hole-indicator of residual stresses and the geometric parameters of the sample were developed based on the analysis of numerical modeling results of typical problems. The research results demonstrate the effectiveness of using the digital image correlation method and the authors’ software for mathematical processing of tangential displacement fields to determine significantly inhomogeneous residual stress fields based on the “large hole” drilling method. The relative maximum deviation of residual stresses at characteristic points around the hole from their initial values does not exceed 4%, and the overall root-mean-square deviation is less than 7%.

The main problems of tribomechanics of high-speed electric centrifugal submersible pumps of the ESP AKM series (nominal speed 10 000 rpm) when operating in complicated oil wells are presented.

The results of computational and experimental studies of vane pump modeling are presented. The distribution of wear of the radial seals and the vibration velocity along the length of the pump section, as well as the assumed shape of the elastic line of the shaft during rotation, were obtained. The kinetic equation of abrasive wear, the equation of flow through the gap, and the equation of the rate of wear are proposed.

One of the main tasks when creating new technical solutions in mechanical engineering is the analysis of their novelty or innovativeness. The novelty and uniqueness of technical solutions is assessed by the degree to which the synthesized solutions differ from existing ones. The potential for development and improvement of technical solutions, as well as the ability to respond to environmental changes, is assessed. This article discusses two cases of determining the novelty of synthesized solutions in comparison with the basic set of options and reference options. Finally, it is concluded that the proposed approach improves the reliability of models adopted at the technical proposal stage.

An overview and classification of simulation programs are presented, and the history of the development of simulators in various fields of activity are examined. The geometric shapes of each element of the machine were compiled in the Autodesk Inventor application. Materials and textures were applied using the Blender application. To evaluate a virtual simulator for studying the technology of turning operations on the ST16K20 machine, function-oriented metrics were calculated. A fragment of the code listing is given for the development of a virtual simulator for studying the technology of turning operations on the ST16K20 machine.

This article is devoted to study of the process of restoring the boom pin of a remote-controlled demolition machine by applying a surface layer of caprolon with graphite filler in order to increase the service life and ensure the durability of the joint.

Buckling and ultimate failure loads for hybrid composite plates with different reinforcement structures under compression and shear loading are studied. The critical buckling loads and load-bearing capacity of hybrid plates under compression, shear, and their combined action are determined. The influence of the structural parameters of hybrid compositions on the postbuckling behavior and failure is shown; the ways of increasing the efficiency of combining heterogeneous layers under combined compression and shear are revealed.

A modern approach to personalized recommendation systems is presented, combining graph neural networks GNN with RL reinforcement learning methods. The GNN model is optimized for recommendation systems and is trained on vector representations of users and products, which are used to generate an initial list of recommendations that are fed into the RL model. Particular attention is paid to the architecture and operation of the integrated GNN-RL model. The results of experimental studies demonstrating the effectiveness of the proposed approach are presented.

The foundational aspects of fixation theory are updated, and a revised composition of bases is introduced: mounting, guiding, supporting, double guiding, double supporting, and triple supporting. These bases combine into five sets, each implementable through explicit or hidden bases or their combinations. This study finds that using sets of hidden bases poses significant challenges for object fixation, characterized by the need to determine the positions of support points by contact points on the object, which is achieved through mounting elements. When using a hidden base, the position of the support point is defined by the self-centering mechanism through contact points with the object to be based. Various design schemes for fixation and centering of objects using sets of hidden bases in self-centering mechanisms are considered.

The implantation of nanoparticles into materials using laser shock waves is an advanced method of surface strengthening of light metals and alloys. The strengthening is based on a combination of plastic deformation caused by the well-known laser shock peening and the high mechanical characteristics of solid nanoparticles. This article discusses specific interconnections between the strengthening mechanisms and the properties of the surface processed by laser shock waves. When such a technology is used, the strengthening effect is found to be provided by two main factors: the gradient microstructure caused by plastic deformation and the gradient depth distribution of implanted SiC particles. Three competing mechanisms affect the strengthening when a laser shock wave is applied to gradient reinforced layers: dispersion strengthening with SiC nanoparticles, grain refinement, and dislocation strengthening. The contribution of each strengthening mechanism to the total strengthening was studied using a modified Clyne computational model.