Fastening Methods Research Articles

Study on the tightening scheme of electronic component screw assemblies based on finite element simulation

Abstract To improve the fastening effect of electronic components in mechatronic equipment, the tightening sequence and frequency have a significant impact on the structural performance of these components. This study identifies an optimal fastening method through experimental verification, although some measurement errors were noted; the method remains highly reliable. First, theoretical calculations and experimental analyses were conducted to determine the torque values under different conditions. Then, simulations were performed to study the impact on the stress of each screw. Finally, experimental validation of the simulation results was carried out, and a linear relationship (with a value of 0.82) between the measured and theoretical values was explored. Consequently, an optimized screw group fastening method is proposed, and the torque calculation process is simplified, thereby enhancing the reliability and lifespan of electronic components in mechatronic systems.

Experimental Evaluation of Geometric and Environmental Effects on Mechanically Fastened Non-Crimp Fabric Composites.

Corresponding to marine environmental regulations is important in shipbuilding and marine industries. The application of lightweight composite materials on ships is an effective approach to reducing the emission of greenhouse gases. The mechanical fastening method is a good candidate to assemble composites and conventional metals. The joint geometric and environmental effects are two important factors in mechanically fastened ship and marine structures. In this study, we evaluated the W/D (hole diameter to width ratio) and environmental effects on the bearing strength and failure mode of a mechanically fastened non-crimp fabric (NCF) composite material. To consider the effect of joint geometry, wherein hole diameters of 5, 6, 8, and 10 mm were machined. Further, by selecting three environmental conditions (UV, saltwater and low temperature), we evaluated environmental effects on bearing strength and failure modes of NCF composite specimens. The bearing strength increased as W/D decreased, and the bearing strength of the specimen exposed to low temperature and UV environments increased, while that of the specimen exposed to saltwater remained the same. From the failure mode analysis, the specimen that was exposed to salt fog showed the same failure mode as the unaged specimen. It was observed that the changes in the transition section and new failure mode in the xenon arc and low-temperature specimens.

Моделирование конструкций сборного абразивного инструмента

Introduction. Grinding is one of the most common types of finishing. It allows the production of surfaces with the required quality parameters and is one of the most available and productive methods for machining high-strength and difficult-to-machine materials. Grinding wheels represent the most prevalent application of grinding technology in mechanical engineering. The use of this abrasive tool helps to increase processing productivity by ensuring the removal of a significant layer of material. In addition, grinding wheels have a longer service life and are widely used in the implementation of hybrid technologies based on the combination of mechanical (abrasive), electrical, chemical, and thermal effects in various combinations. A variety of tool body shapes and types of abrasives allow the use of wheels in a wide variety of production areas. One of the ways to analyze and design a new tool is numerical simulation. In this research, graphic modeling was selected as the most appropriate method for representing the future design of the tool. This approach allows for a more straightforward conceptualization process compared to other modeling techniques. The purpose of the work is to simulate a modular abrasive tool in order to analyze and synthesize structures to increase the efficiency of tool support for the manufacture of products made of high-strength and difficult-to-process materials using traditional or hybrid processing technologies. Research methodology. Theoretical studies are carried out using the basic principles of system analysis, geometric theory of surface formation, cutting tool design, graph theory, mathematical and computer simulation. To solve the problem, we have studied the available designs of modular grinding wheels. There has also been the analysis of the types of abrasive parts, methods of fastening of the abrasive cutting part on the wheel’s body, the materials used for the manufacture of the body, the characteristics of the body of the wheel, and fastening schemes. Results and discussions. A simulation technique based on graphic modelling theory has been developed. A comprehensive investigation of the existing design of the grinding wheel has enabled the identification of the key structural elements that define its design. The data obtained has been used to create a generalized graphic simulation of a modular abrasive tool. This simulation integrates all the components and displays a conditional constructive relationship between them. The developed design methodology was tested on an example of two designs of modular grinding wheels. The theoretical studies established that the design efficiency of modular abrasive tools can be increased by 2–4 times by using the developed simulation technique.

Delamination prevention of composite joints with asymmetric carbon-fiber reinforced plastic adherends

The use of adhesive bonding in aeronautical applications has gained popularity due to its numerous advantages over traditional mechanical fastening methods. However, the issue of delamination still poses a significant challenge in fully embracing this technology in the industry. This study proposes a unique approach to optimize carbon fiber reinforced polymer (CFRP) single lap joints (SLJ) by introducing a curved joint design with varying adhesive thickness. The curvature is achieved through the intentional warpage caused by residual stresses resulting from an asymmetrical composite layup. While these residual stresses can potentially lead to cracks and distortions, this research aims to leverage their presence to enhance joint performance and mitigate delamination risks. A comprehensive analysis, involving both numerical simulations and experimental testing was conducted to compare the performance of the curved joint design with traditional configurations. The findings indicate that the curved joint design effectively prevents delamination while maintaining comparable joint strength. This demonstrates the potential benefits of employing curved joints for aeronautical components with curved geometries, affirming the feasibility and advantages of this approach. However, further optimization of the curved joint configuration is warranted to enhance its performance and expand its applicability to a broader range of applications.

Study of the dynamic process in a nonlinear mathematical model of the transverse oscillations of a moving beam under perturbed boundary conditions

The study of transverse oscillations of systems moving along their axis is a very difficult, but at the same time a very important task. Mathematical models of nonlinear transverse oscillations of a beam moving along its axis are analyzed in this paper work, both for non-resonant and resonant cases. The task becomes even more complicated if we additionally take into account the method of fastening the ends of the beam or the perturbation at its ends. We have obtained dependencies that can be used in construction, transport, industry, mechanical engineering and other domains of technology, ensuring the stability and safety of the operation of such mechanical systems. Mathematical models have been obtained for structural engineers to determine the amplitude–frequency response of relevant structures. These mathematical models are key to researching the dynamics of moving media. The obtained results allow considering not only the influence of kinematic and physical-mechanical parameters on the amplitude–amplitude frequency response of the medium, but also the fastening method. In addition, the correlations obtained in the paper make it possible to study not only the influence of the moving medium parameters on the nature of changes in the frequency and amplitude of oscillations, but also to consider the movement at the points of support of the medium. Namely, even at the stage of designing a pipeline for a liquid flowing at a certain speed, it is possible to consider the influence of the oscillation of the supports or their fastening method on the dynamics of the oscillatory process. The resulting dependencies allow designers to consider the influence of the characteristics given in the paper with a high level of accuracy and predict dynamic phenomena in them. In engineering calculations of various mechanical systems, the resulting dependencies can be used to optimize parameters to avoid negative destructive phenomena during operation.

Design for Assembly: Wrist Orthosis Design Concepts Proposals

This study investigates the integration of modern engineering techniques, including 3D scanning and additive manufacturing, in the design and production of wrist orthoses. The research aims to enhance orthotic devices by proposing three innovative fastening methods - Velcro straps, screws, and magnets - designed for use with 3D-printed orthoses. The study outlines the entire process from patient hand scanning to the final orthosis creation, emphasizing the precision and customization afforded by these advanced technologies. The proposed designs are intended to improve the comfort, effectiveness, and usability of orthoses for patients with musculoskeletal dysfunctions. The findings demonstrate the potential for significant advancements in personalized medical devices, offering new avenues for rehabilitation and patient care.

Technological features of OOG transportation by sea transport

The article discusses the features of the transportation of oversized cargo by sea on container ships. The main governing documents and rules for the confirmation and placement of oversized cargo are indicated. The problems are reflected in the guidance documentation, since at the moment it is impossible to take into account all the features of a specific oversized cargo when creating a loading plan and cargo fastening tools on a flat rack. The scheme of placement of oversized cargo on a container ship is given. Options for attaching oversized cargo to a flat rack are considered in detail. The loads are divided into categories, for each of which the methods of fastening are given in accordance with the peculiarities of the geometric shapes of the load and the weight distribution. The conclusion indicates the need to create a software module for standardizing the rules for loading oversized cargo, which will systematize all the characteristics of oversized cargo, calculate the best options for placing cargo on a ship, taking into account the safety requirements and optimality of the cargo plan, reduce accidents during loading / unloading and transportation. It was also noted that the standardization of the loading module for oversized cargo will allow integrating information about the transportation of oversized cargo into the overall system for determining the efficiency and quality of container shipping.

Design and fabrication of a wrist splint for burn patient rehabilitation using 3D printing technologies.

Severe and common injuries involving burns to the hands and wrists can often lead to permanent loss of motion. The issue is exacerbated by the delicate nature of tendons and muscles in the hands, along with the formation of scar tissue. While rehabilitation exercises can help improve the range of motion, early-stage recovery requires additional tension on the affected areas. To address this concern, a novel project was initiated, aiming to develop a specialized splint for later-stage rehabilitation. This innovative splint allows users to carry out their daily tasks while wearing it, constantly applying a beneficial load on the wrist, hand, and digits to enhance range of motion. The development of the splint involved leveraging Fused Deposition Modelling (FDM) 3D printing and medically safe materials for the initial prototype. Finite Element Analysis (FEA) was employed to analyze the design. The process underwent iterative design improvements and parameter adjustments, ultimately resulting in the final prototype. The FEA analysis confirmed the strength and durability of the PLA components, while the TPU digit resistance bands were evaluated using a hyper-elastic model. As a result, the final design effectively applies tension to the digits without compromising day-to-day tasks’ usability and wearer’s comfort. Future iterations of the splint could focus on enhancing fastening methods, reducing brace movement during usage, creating various sizes to accommodate different arm/hand dimensions, and optimizing mass-manufacturing processes.

Ethnic and Cultural Affiliation of the Xichaogou Burial Ground Based on Materials of the Xiongnu Culture Belt Plaques

Purpose of the work is to determine the ethnic and cultural affiliation of the population that left the Xichaogou burial ground. Xichaogou is an expressive archaeological complex located in the Liaoning region of China. The uniqueness of this necropolis lies in the fact that several hundred burials of varying degrees of preservation have been recorded in it. Inventory complexes of burials include ceramics, objects made of bronze, iron and stone. The materials of the site demonstrate the features of various cultures – Xiongnu, Buyeo, Han, Xianbi and etc. Since the burial inventory of the Xichaogou burial site demonstrates multicultural features, the question of the ethnic and cultural affiliation of the population that created this site is debatable.Materials and methods. In previous works, the problem of ethnic identification of the Xichaogou burial ground was solved on the basis of certain categories of grave artefacts. In this paper, the questions of the ethnic and cultural affiliation of the Xichaogou sie are considered on the material of the belt plaques decorated in the animal style. The main reason for this choice of material is that the shape and ornament of belt plaques reflect the ethnic and cultural identity of an individual or group in nomadic cultures. 17 belt plaques were found at the Xichaogou site. The entire amount of material is divided into 3 types according to such features as shape, rim ornament (teardrop-shaped, dotted, herringbone), manufacturing technique (presence of through openwork holes), method of fastening (presence of eyelets on the back side), function as part of a belt set (presence peg). A search for analogies to the groups of belt plaques in the Xiongnu culture, identified in the materials of the Sichagou site, has been undertaken.Result. It has been established that belt plaques from the materials of the Xichaogou burial ground find analogies in the vast territory of the Xiongnu culture in Northern Eurasia.Conclusion. It can be concluded that the population that created the Xichaogou site does not belong to the Xiongnu by ethnic origin, but was strongly influenced by this culture. The population of Xichaogou was formed on the basis of the local culture of the previous period. Various and diverse cultures of the eastern part of the Liaoning and the western part of the Jilin regions also contributed to its formation. At the current stage it is possible to identify the Xiongnu and Buyeo cultural components.

Mechanical Fastening Methods of Polymer-Based Composites

Mechanical Fastening Methods of Polymer-Based Composites

Container and contrailer transpportation by rail increasing by innovative fastening method implementation

Container and contrailer transpportation by rail increasing by innovative fastening method implementation

Оперативный геодезический контроль деформаций призабойной зоны при инновационных технологиях проходки туннелей

Purpose: To consider the issue on performance of operational control of deformations of tunnel bottomhole zone with the use of ground-based laser scanning technology when tunneling with New Austrian tunneling method which is the most progressive one and feasible in economics terms for underground building construction by mining. The essence of this method is in that as a support for tunnel bottom-hole zone, a self-supporting shell made of sprayed concrete without traditional fastening method usage is applied that allows to save time for tunneling significantly, especially of those tunnels which have complex geometry and non-standard dimensions. At the same, the conceptual basis for this method is the necessity to identify operatively bottomhole zone soil mass deformations that’s justified by the need to provide job realization safety. Methods: As a major method for to determine tunnel bottomhole zone geospatial position it is proposed to consider ground-based laser scanning technology. Scanning result processing was implemented in specialized software package Leica Cyclone 3DR. Results: Existing experience of geodetic check of deformations in tunneling by New Austrian method is considered. Processing results for data on ground laser scanning of a tunnel separate fragment are presented, a tunnel mathematical three-dimensional model is obtained and assessment of deviations of tunnel actual surface from obtained theoretical one is fulfilled. Practical significance: The obtained threedimensional model can be further used for geodetic monitoring of deformations. Theoretical bases for estimation required accuracy for deformation characteristics definition are substantiated which are based on the transition from construction tolerances to average quadratic errors of deformation characteristics definition and then to average quadratic errors of coordinates for laser scanning points. The enlarged stages of scanning are defined with view of tunneling technology of New Austrian method.

Seismic performance evaluations of modular house having 4-clip fastening method

Seismic performance evaluations of modular house having 4-clip fastening method

Study on Effect of Process Variable on Fastening Quality Using Process Monitoring Data of Flow Drill Screwed 590DP Steel/AA5052 combination

The reduction of the weight of a vehicle body to improve fuel efficiency has been garnering widespread interest in the automobile industry. As the use of lighter materials increases, the joint of the dissimilar materials becomes crucial to guarantee the rigidity of the vehicle body. Amongst the joining methods for various multi-materials, the flow drill screw (FDS) is a fastening method that can mechanically join two or more plates using fasteners at high speed with a one-sided approach. Several studies have been conducted on the FDS joint quality with process parameters. However, a majority of them are focused on similar aluminum combinations and joint quality with various rotation speeds and downforce. The monitoring data analysis for the FDS joint of 590DP Steel/AA5052 combination and its fastening quality with the various process variables has been investigated in this study. The downforce and feed rate affect the process time required for the penetration stage. The maximum temperature reached during the process decreases as the downforce and feed rate increase. In addition, the critical torque value must be satisfied to ensure a defect-free joint. The combination of the downforce, feed rate, and torque affect the size of the gap at the joint interface. A high torque value can reduce the gap in the final tightening step. However, the joint strength of the FDS did not show differences with the gap. All the joints failed the pull-out mode when the fastener was released from the lower aluminum sheet.

ВПЛИВ СТУПЕНЯ ЗАКРІПЛЕННЯ ОБМОТКИ В ТОРЦІ ПАЗА СТАТОРА ТУРБОГЕНЕРАТОРА НА ТЕРМОМЕХАНІЧНІ ХАРАКТЕРИСТИКИ ІЗОЛЯЦІЇ ЇЇ СТЕРЖНЯ

Based on the finite element method, a numerical method for calculating thermomechanical movements and stresses of the components of the stator winding of a powerful turbogenerator is proposed, taking into account its regime and structural factors. The results of studies of these characteristics in insulation along the length of the core in radial and axial directions in different variants of fixing the winding in the end zone of the core are presented. The regularities of distribution of maximum and average values of thermomechanical parameters in the groove and frontal parts with the traditional method of fastening and the presence of a free section of the core in the end zone of the stator in the nominal mode of operation of the generator are determined. Ref. 12, fig. 4.

Comparative Analysis of Cartons for the Substrate in Special Shoes of the Sandal-Glue Method of Fastening

Comparative Analysis of Cartons for the Substrate in Special Shoes of the Sandal-Glue Method of Fastening

Research into technology of fastening the mine workings in the conditions of unstable masses

Purpose.Determination of the rock stability along the strike of the mass, where the drift mining of the horizon -480 m is conducted, considering the possibility of using the improved types of supports in the conditions of the 10th Anniversary of Kazakhstan’s Independence mine at the Khromtau field with the substantiation of using the effective type of fastening that increases technical and technological, operational and economic indicators of the mine. Methods. Numerical modelling of the stress-strain state of the rock mass applied at the mine have been performed using the RS2 software in a two-dimensional formulation. The rock mass state, as well as the physical-mechanical properties of mine rocks are determined according to building codes and regulations (SNiP II-94-80), depending on the category of the rock stability. Findings. It has been revealed that the combined supports from rock bolts and shotcrete are the most rational type of fastening in the studied mine. The efficiency and prospects of using the combined supports have been determined, which ensure a decrease in their material consumption and cost while increasing the reliability of mine workings and the labor productivity of miners. The use of combined support allows to increase the economy of materials for support by 1.7 times, as well as to increase the drifting rate by 1.6 times in comparison with the metal support. Originality.The paper proposes a new approach to substantiation of an effective fastening method by comparing the costs when driving horizontal underground mine workings in the mining-and-geological conditions of the 10th Anniversary of Kazakhstan’s Independence mine. Practical implications.The research results can be used when planning mining operations, in particular, stable fastening methods at the 10th Anniversary of Kazakhstan’s Independence mine of the Khromtay deposit, as well as other mining enterprises with similar mining-and-geological conditions.

Effect of interference on the press fitting of railway wheel and axle assemblies

Press fitting is one of the common fastening methods used to assemble mechanical components. It has also received considerable critical many industrial applications, for example, railway wheel and axle are usually assembled by press-fitting. This process generates high stress on the axle-fillet area and fatigue is generally initiated due to the stress concentration. This paper attempts to propose the stress distribution and deformation of a railway axle. Various interference clearances were analyzed using finite element method. The contact pressure at the axle wheel seat along the axial direction was examined as it significantly influences the press-fitted components life. The analytical results from Lame’s theory [1] were compared with finite element analysis results for the wheel and axle press-fitting process. The results obtained from both methods were in good agreement and the maximum relative error of the contact pressure is by 11.08 %. Additionally, the results show that the Von-Mises stresses on the axle wheel seat and fillet areas were found to be increased if the interference increased.

소프트 웨어러블 슈트용 액추에이터의 토크 전달 향상을 위한 기능적 설계 연구

This paper proposes a functional design to improve the torque transmission of a wearable suit for walking assistance. The proposed functional design includes a soft actuator, lower-limb support module, and their fastening method. First, the features and functions of the soft actuator and lower-limb support module are described. In addition, according to the elasticity of the fixed band and the relative positions of the fixed band, soft actuator, and lower-limb support module, a fastening method to maximize the torque transmission performance was determined experimentally. Thus, an optimal fastening method was derived, and the functional design of a soft wearable suit applying this method was developed.

Застосування огородження склопластикового композитного перильного

Introduction. Innovative, new materials are increasingly used in transport construction, among which composite materials are becoming widespread.Small bridges and elements of large bridges, such as roadway slabs, pavements, railings, composite reinforcement, reinforcement elements, are made of composite materials.Recently, the use of polymer composite materials for the manufacture of lightly loaded structural elements of transport structures, such as lighting poles, drainage trays, railings.Much attention should be paid to the fiberglass composite railing, which has a number of advantages over traditional metal fencing. Unfortunately, at present there are no clearly defined in Ukraine regulations on fiberglass composite fencing, so this topic is relevant and necessary for the transport industry.Problem Statement. From the literature analysis it is established that the railings of highways and sidewalks are in difficult operating conditions, are constantly exposed to aggressive environments - water, chemicals, salts.Goal. Increasing the durability of the railing by using new materials.Results. The analysis of production of a fiberglass profile is carried out. On the basis of the conducted researches the general requirements to a protection of fiberglass composite washing machine are established. On the basis of the current normative documents the classification of a protection on a place of installation, type of filling of a skeleton, a method of fastening of risers is developed. The paper presents the main parameters and dimensions of the fence. Material requirements are set. Methods of control of a protection with establishment of a technique of test of a protection on resistance to action of horizontal and vertical loadings are developed. Recommendations on installation and installation of a protection of fiberglass composite washing machine are offered.Conclusions. The research results were used in the development of technical conditions for the protection of fiberglass composite washing machine.Keywords: road, composite, bridge, fencing, profile, fiberglass, artificial construction