Artículos de revistas: "Shaft hub"

1

Vetter, Sebastian, Erhard Leidich, Kai Neikes, Berthold Schlecht y Alexander Hasse. "The survival probability of shafts and shaft-hub connections". Engineering Failure Analysis 103 (septiembre de 2019): 195–202. http://dx.doi.org/10.1016/j.engfailanal.2019.05.007.

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2

Croccolo, D. y N. Vincenzi. "Stress concentration factors in compression—fit couplings". Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 224, n.º 6 (1 de junio de 2010): 1143–52. http://dx.doi.org/10.1243/09544062jmes1881.

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The aim of the present work is to define the maximum stress generated by the coupling of axially symmetric and continuous shafts press-fitted into axially symmetric hubs. The theoretical stresses given by the well-known formulae of the thick-walled cylinders theory are constant on the whole coupling surface, but if the shaft extends beyond the hub there is a stress concentration factor on the boundary zone. This occurrence is confirmed by finite element analyses performed by the authors on several different shaft—hub couplings. The analysed couplings have the shaft extended beyond the hub, the shafts press-fitted into the hubs, and both shafts and hubs loaded by an external pressure and an internal pressure. The stress concentration factors have been calculated in this work and their expressions have been derived as a function of some tensile and geometrical parameters. By combining the thick-walled cylinders theory with the proposed formulae, it is possible to evaluate the maximum stress located at the end of the hub without performing any numerical investigations.

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3

Lee, Dong-Hyung, Ha-Young Choi, Seok-Jin Kwon y Jeong-Won Seo. "Optimization of Contact Edge Profile for Minimizing Contact Pressure in a Press-fitted Shaft". MATEC Web of Conferences 165 (2018): 22029. http://dx.doi.org/10.1051/matecconf/201816522029.

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In the shrink or press-fitted shafts such as railway axles, the rotor of a steam turbine or coupling, a high-stress concentration takes place in the close of contact edge due to relative slip between shaft and boss in a press-fitted shaft and this is a major cause of fatigue failure of the shaft. The object of this paper is to build a finite element analysis model for analysing press-fitted and bending load condition in a pressfitted assembly and is to propose a hub shape optimization method to minimize a contact pressure in the close of shaft contact edge. Numerical asymmetric-axisymmetric finite element model was developed to predict the contact stress state of the press-fitted shaft. Global optimization method, genetic algorithm, and local optimization method, sequential quadratic programming, was applied to the press-fitted assembly to optimize the hub contact edge geometry. The results showed that the maximum contact pressure with optimized hub shape decreased more than 60% compared to conventional hub shape, the maximum contact stress affecting fatigue life reduced about 47%. In addition, hub shape optimization design could be a useful tool, able to increase the load capabilities of press fits concerning wear and fatigue behaviour.

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4

Dörr, Florian, Michael Funk, Mathias Liewald, Hansgeorg Binz y Marco Savino. "Determination of Friction Coefficients of Interstice of a Shaft-Hub-Connection Manufactured by Lateral Extrusion". Advanced Materials Research 966-967 (junio de 2014): 659–70. http://dx.doi.org/10.4028/www.scientific.net/amr.966-967.659.

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A combination of several manufacturing process steps in a simultaneous manner allows savings in energy costs, reduced investment and economizing logistical efforts. In particular, this investigation deals with manufacturing and joining of a frictionally engaged shaft-hub-connection by lateral extrusion. One key challenge of such new process management is the prior layout of both optimal friction conditions during manufacturing process on the one hand and highly expected static friction interaction of joined components in order to transmit tangential and axial forces on the other hand. Therefore, cylindrical, thin-walled hubs have been manufactured and joined to shafts. Several parameters describing the tribological system between shaft and hub such as contact surface topographies and lubricant, have been varied within this study. By measuring the radial deformation of the hub, the contact pressure is determined and a normal force applied to the contact surface of shaft and hub is calculated. When separating hub and shaft in a destructive manner, an extensive axial tensile force is applied and measured. According to Coulomb's friction law, specific friction coefficients are calculated depending on manufacturing process parameters as mentioned above.

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5

Yang, Guang Xue, Qiang Li y Ji Long Xie. "Experiment Research on the Influence of Fretting on Crack Propagation". Advanced Materials Research 228-229 (abril de 2011): 617–20. http://dx.doi.org/10.4028/www.scientific.net/amr.228-229.617.

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In order to investigate the influence of fretting induced by a shrink-fit shaft and hub subjected to rotating bending on crack propagation on different position, small specimens consisted of shaft and hub were tested on the four point rotating bending fatigue test machine. The experimental result shows that the fretting fatigue life of specimen with notch outside the shaft-hub contact is shortest, and the fretting fatigue life of specimen with notch inside the shaft-hub contact is longest.

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6

Radi, E., L. Lanzoni, A. Strozzi y E. Bertocchi. "Shaft-hub press fit subjected to bending couples: Analytical evaluation of the shaft-hub detachment couple". Applied Mathematical Modelling 50 (octubre de 2017): 135–60. http://dx.doi.org/10.1016/j.apm.2017.05.018.

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7

Ziaei, Masoud. "Bending Stresses and Deformations in Prismatic Profiled Shafts with Noncircular Contours Based on Higher Hybrid Trochoids". Applied Mechanics 3, n.º 3 (23 de agosto de 2022): 1063–79. http://dx.doi.org/10.3390/applmech3030060.

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This paper presents an analytical method for determining the bending stresses and deformations in prismatic, noncircular profile shafts with trochoidal cross sections. The so-called higher trochoids can be used as form-fit shaft-hub connections. Hybrid (mixed) higher trochoids (M-profiles) were developed for the special application as a profile contour for the form-fit shaft and hub connections in an earlier work by the author. M-profiles combine the advantages of the two standardised polygonal and spline contours, which are used as shaft-hub connections for the transmission of high torques. In this study, the geometric and mechanical properties of the higher hybrid trochoids were investigated using complex functions to simplify the calculations. The pure bending stress and shaft deflection were determined for M-profiles using bending theory based on the theory of mathematical elasticity. The loading cases consisted of static and rotating bends. Analytical, numerical, and experimental results agreed well. The calculation formulas developed in this work enable reliable and low-cost dimensioning with regard to the stresses and elastic deformations of profile shafts subjected to bending loads.

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8

Esebeck, G. v., M. Kising y U. Neuhof. "Investigation on Ceramic–Metal Joints for Shaft–Hub Connections in Gas Turbines". Journal of Engineering for Gas Turbines and Power 118, n.º 3 (1 de julio de 1996): 626–31. http://dx.doi.org/10.1115/1.2816694.

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This paper shows possibilities for joining ceramic rotors to metal shafts. The investigations presented include exemplary joining methods for shaft–hub connections for ceramic rotors in gas turbines, as positive, permanent locking, or a combination of both. Active brazing as well as the combination of brazing or adhesive bonding and positive locking are discussed. Different shaft–hub connections were tested. The results of experimental investigations as static shear, bending, and torsion tests as well as dynamic torsion tests will be presented. In addition to the experimental investigations, finite-element analyses were made. Elastic calculations on simple geometries have shown the influence of different parameters like the thermal coefficients and the geometry at the joint face. Calculations were done to reduce the induced tensile stress in the joint and to increase carrying capacity. The calculations were also transferred to the shaft–hub connections to optimize the geometry of the joint faces.

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9

Croccolo, D. y N. Vincenzi. "A generalized theory for shaft—hub couplings". Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 223, n.º 10 (29 de junio de 2009): 2231–39. http://dx.doi.org/10.1243/09544062jmes1437.

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The design of compression-fit joints, based on the theory of thick-walled cylinders, is usually referred to shaft—hub couplings carried out between two elements that have an axial symmetric shape. The stress distributions both inside the elements and on the contact surfaces can be defined by the equilibrium and by the compatibility formulae once the total radial interference and the internal and external pressure (the boundary conditions) are known. The complete tensile state of the coupling is defined by two principal stresses: the radial and the hoop tensions. The present article aims at extending the analytic calculation valid for two elements to a number of n elements by means of a sequential solution of the governing equation system. The elements in contact can rotate at a generic angular velocity and can, also, be made of different materials. The overall solution has been derived starting from the hypothesis of the simultaneous presence of axial symmetric geometries and axial symmetric loads. The mathematical model has been verified by comparing the theoretical results with some finite-element analysis calculations performed on the same coupled elements.

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10

Leidich, E., F. Reiß y R. Schreiter. "Investigations of hypocycloidal shaft and hub connections". Materialwissenschaft und Werkstofftechnik 48, n.º 8 (agosto de 2017): 760–66. http://dx.doi.org/10.1002/mawe.201700013.

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11

Meissner, Robert Jean-Phillipp, Mathias Liewald, Daniel Ulrich y Hansgeorg Binz. "Numerical study on the applicability to manufacturing of contact-stress-optimised shaft-hub connections joined by lateral extrusion". Manufacturing Review 7 (2020): 21. http://dx.doi.org/10.1051/mfreview/2020016.

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Shaft-hub connections, which are joined by plastic deformation of at least one component (e.g. joining by lateral extrusion), can meet today's contradictory requirements for high power densities with low manufacturing costs. As opposed to classical manufacturing methods, the tight manufacturing tolerances of shafts and hubs are not required here since the shaft is formed in the hub during the process to generate a combined frictional and positive-locking connection. However, plastic deformation generally results in an uneven distribution of contact stress, which causes negative effects such as increased hub stress and deformation, as well as the reduced transmission capacity of the connection. To overcome this effect, an iterative design approach for plastically stressed shaft-hub connections was developed in Ulrich et al. (2019)[1], in which the contact-stress distribution is influenced by contouring of the hub contact surface. Nonetheless, one major challenge in this process is the high sensitivity of the stress distribution to contour changes, particularly in the edge area of the connection, meaning that a dependency on tight manufacturing tolerances is present here, too. Therefore, an investigation is conducted to determine the extent to which deviations in the manufacturing process of the components, in the tool quality and during joining by lateral extrusion influence the resulting contact stress. In order to achieve this goal, numerical investigations are carried out, and the effects on the resulting contact-stress distribution are analysed. Finally, recommendations for manufacturing accuracy and process limits are derived in order to ensure manufacturability and enable the transfer of technology to industrial applications involving shaft-hub connections joined by lateral extrusion.

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12

Bertocchi, Enrico, Luca Lanzoni, Sara Mantovani, Enrico Radi y Antonio Strozzi. "Shaft-hub press fit subjected to couples and radial forces: analytical evaluation of the shaft-hub detachment loading". Journal of Mechanics of Materials and Structures 13, n.º 3 (31 de agosto de 2018): 283–96. http://dx.doi.org/10.2140/jomms.2018.13.283.

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13

Lü, Bao Zhan y Kun Liu. "Research on Stress and Strain in Isometric Polygonal Profile Connection Based on FEM". Key Engineering Materials 460-461 (enero de 2011): 369–73. http://dx.doi.org/10.4028/www.scientific.net/kem.460-461.369.

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Because of the problem of key joint or spline joint, the isometric polygonal profile connection was put forward, and the mathematical model of isometric polygonal curve was analyzed in this paper. Based on the periodicity characteristics of equivalent effective stress and total displacement in the whole structure through preliminary analysis, 1/3 structure of isometric polygonal profile shaft and hub was adopted during geometry model being established. The shearing strength in isometric polygonal profile hub and shaft, the main stress in hub and the total strain in shaft were calculated and analyzed based FEM.

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14

Ochs, Georg, Henrik Buse, Alexander Hüttinger, Markus Wöppermann y Jörg Hermes. "Vergleichbarkeit von Prüfmethoden auf unterschiedlichen Modellebenen zur Qualifikation einer Anti-Fretting-Paste". Tribologie und Schmierungstechnik 69, n.º 4 (26 de septiembre de 2022): 48–52. http://dx.doi.org/10.24053/tus-2022-0023.

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Anti-fretting pastes are an effective way of protecting the contact partners of shaft-hub connections in an industrial drive system from the wear phenomenon of fretting. qulification of an anti-fretting paste in the entire industrial drive system is not economically feasible due to the wide range of environmental influences. Therefore, the tribological system of a shaft-hub connection is abstracted along a test chain on model levels and investigated on model test rigs. the results are validated using a near-field application with real shaft-hub connections to finally derive a suitalbe model test for future qualification.

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15

Jusoh, Mohd Hanapi, Mohd Fais Ismail y Mohd Sailuddin Mamat. "Development of Conceptual Design for Wheel Hub Retainer Tool". Engineering, Agriculture, Science and Technology Journal (EAST-J) 1, n.º 1 (25 de julio de 2022): 1–6. http://dx.doi.org/10.37698/eastj.v1i1.111.

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A wheel hub retainer tool is a tool used to facilitate maintenance and drive shaft replacement. The drive shaft will suffer from wear and tear as the age of a car increases and the driving style is relatively rugged. on the side of the road. The method of opening the drive shaft nut manually requires a special tool as a hub retainer when the nut is opened so that the hub will not also rotate in the same direction as the nut rotation. The absence of special tools to hold the hub when opening the drive shaft nut led to the existence of various techniques and ways to open the drive shaft nut by mechanics. However, it is feared that this situation could cause damage to other components such as broken or bent bold studs that could slow down maintenance work or drive shaft replacement. The conceptual design for designing this tool involves a morphology chart and design selection based on Weighing Result Matrix Table. There are four design concept options that have been studied. Based on the selection of the best concept, a selected design concept involves five components that can be stitched together. As a result of this study, a concept design has been produced with the appropriate dimensions.

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16

Xiong, Ling, Peng Shang y You Lin Xu. "Exact Solution of Stress and Radial Displacement of Elastic Tapered Interference Fit". Applied Mechanics and Materials 423-426 (septiembre de 2013): 1438–43. http://dx.doi.org/10.4028/www.scientific.net/amm.423-426.1438.

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Tapered interference fits, which can transfer large torques, are widely used in the connection design for propeller hubs and shafts of large vessels. In this paper, a model was developed to study the influences of torques, rotational speeds and tapers on the tapered interference fit between a propeller hub and a shaft. Using the classic elastic plane stress theory, the exact solutions of the radial stresses, tangential stresses and radial displacements of the propeller hub and shaft are derived. Then the calculation method of the magnitude of the tapered interference fit was presented. Finally taking a screw propeller system as an example, the above solutions were calculated using the numerical method. The results show that improving the stress distribution of the propeller hub is an effective approach to increase the connection strength and torque transmission capacity. If the rotation speed has to be considered, the stress and displacement would be increased significantly due to the centrifugal force. The present analytical solutions are expected to be useful in the structure design of tapered interference fits for propeller hubs and shafts.

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17

Meeus, Hans, Björn Verrelst, David Moens, Patrick Guillaume y Dirk Lefeber. "Experimental Study of the Shaft Penetration Factor on the Torsional Dynamic Response of a Drive Train". Machines 6, n.º 3 (17 de julio de 2018): 31. http://dx.doi.org/10.3390/machines6030031.

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Typical rotating machinery drive trains are prone to torsional vibrations. Especially those drive trains that comprise one or more couplings which connect the multiple shafts. Since these vibrations rarely produce noise or vibration of the stationary frame, their presence is hardly noticeable. Moreover, unless an expensive torsional-related problem has become obvious, such drive trains are not instrumented with torsional vibration measurement equipment. Excessive levels can easily cause damage or even complete failure of the machine. So, when designing or retrofitting a machine, a comprehensive and detailed numerical torsional vibration analysis is crucial to avoid such problems. However, to accurately calculate the torsional modes, one has to account for the penetration effect of the shaft in the coupling hub, indicated by the shaft penetration factor, on the torsional stiffness calculation. Many guidelines and assumptions have been published for the stiffness calculation, however, its effect on the damping and the dynamic amplification factor are less known. In this paper, the effect of the shaft penetration factor, and hence coupling hub-to-shaft connection, on the dynamic torsional response of the system is determined by an experimental study. More specifically, the damping is of major interest. Accordingly, a novel academic test setup is developed in which several configurations, with each a different shaft penetration factor, are considered. Besides, different amplitude levels, along with both a sweep up and down excitation, are used to identify their effect on the torsional response. The measurement results show a significant influence of the shaft penetration factor on the system’s first torsional mode. By increasing the shaft penetration factor, and thus decreasing the hub-to-shaft interference, a clear eigenfrequency drop along with an equally noticeable damping increase, is witnessed. On the contrary, the influence of the sweep up versus down excitation is less pronounced.

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18

Zhao, Xiao Qing y Peng Shang. "Exact Solution of Stresses of Tapered Interference Fit". Applied Mechanics and Materials 556-562 (mayo de 2014): 4284–87. http://dx.doi.org/10.4028/www.scientific.net/amm.556-562.4284.

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Tapered interference fits can avoid the influence of keyways on the parts strength and transfer large torques. In this paper, a model was developed to study the influence of the taper on the interference fit between a propeller hub and a shaft. Using the classic elastic plane stress theory, the exact solutions of the radial stresses, tangential stresses and radial displacements of the propeller hub and shaft are derived. Then the calculation method of the magnitude of the tapered interference fit was presented. Finally taking a screw propeller system as an example, the above solutions were calculated by using the numerical method. The results show that the taper plays a key role in the interference fit. Improving the stress distribution of the propeller hub is an effective approach to increase the connection strength. The present analytical solutions are expected to be useful in the structure design of tapered interference fits for propeller hubs and shafts.

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19

Jones, I. A., Christopher E. Truman y Julian D. Booker. "Photoelastic Investigation of Friction and Residual Stress in Shrink-Fitted Shafts and Hubs". Applied Mechanics and Materials 1-2 (septiembre de 2004): 171–78. http://dx.doi.org/10.4028/www.scientific.net/amm.1-2.171.

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This paper describes initial investigations into the use of frozen-stress photoelasticity to study the development of slippage within shrink-fitted shaft/hub pairs, with the aim of studying the residual stresses remaining after partial slippage has occurred. Results to date show the feasibility of measuring the shear stresses along the partially-slipping interface between shaft and hub.

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20

Li, Wen Jing, Hua Sun y Rui Xiang Chen. "Contact Analysis and Optimization of a New Type of Propeller Shaft-Hub Connection Structure". Advanced Materials Research 328-330 (septiembre de 2011): 801–5. http://dx.doi.org/10.4028/www.scientific.net/amr.328-330.801.

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According to the characteristics of aero products, the products must be as simple and light as possible under the premise of ensuring the performance. Using the finite element analysis software ANSYS to establish a nonlinear contact model about a new type of composite shaft-hub connection structure which is used in the propeller. Based on the model to give a optimization about the elastic ring, part of the shaft-hub connection structure, which defines the semi-cone angleαand the width B of the elastic ring as the design variables, the stress of the elastic ring as the state variables. The optimization results lay the theoretical basis of designing a composite shaft-hub connection structure which meets the requirement of aero products.

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21

Pavlov, Valentin Fyodorovich, Vladimir Stepanovich Vakulyuk, Vyacheslav Petrovich Sazanov y Arsenij Vital'evich Efrosinin. "THE ESTIMATION OF ROLLER STRENGTHENING INFLUENCE ON THE ENDURANCE LIMIT OF SHAFTS WITH PRESSURIZED HUB". Journal of Dynamics and Vibroacoustics 5, n.º 4 (12 de marzo de 2020): 29–35. http://dx.doi.org/10.18287/2409-4579-2019-5-4-29-35.

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The influence of roller strengthening on endurance limit under bending of the 25 mm and 50 mm diameter shafts made of steel 20 and 25 mm diameter shafts made of steel 40X with a pressurized hub has been examined. It’s been stated that the endurance limit of roller strengthened shafts with a pressurized hub depends not only on a value of compressive residual stresses in their dangerous section but on the character of its distribution. The valuation of a surface hardening influence on the endurance limit of shafts by the surface residual stresses criterion and the average integral residual stresses criterion has been shown that the average integral residual stresses criterion calculated through the part’s dangerous section surface layer thickness equal the critical depth of the non-propagating fatigue crack can be recommended for the hardened shafts with a pressurized hub endurance limit increase prediction. It’s been shown that on a diameter of a shaft with a pressurized hub raising it is necessary to increase a thickness of a hardened surface layer with compressive residual stresses.

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22

Strozzi, A., A. Baldini, M. Giacopini, E. Bertocchi y L. Bertocchi. "Achievement of a uniform contact pressure in a shaft–hub press-fit". Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 227, n.º 3 (17 de octubre de 2012): 405–19. http://dx.doi.org/10.1177/0954406212461994.

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In this article, the achievement of a uniform elastic contact pressure in a frictionless, keyless, shaft–hub interference fit obtained by properly shaping the mating profiles is examined. The peculiarity of the hub mechanical response according to which, under the effect of a uniform pressure applied to the hub bore, the bore axial profile moves radially without any distortion, is exploited to simplify the determination of the mating profiles that return a uniform pressure. In particular, the hub radial deflection may be computed with a simple plane model, whereas only the shaft radial deflection requires a more complex analysis in cylindrical coordinates. Explicit approximate expressions are reported for the shapes to be conferred to the mating profiles to achieve a uniform pressure. Selected examples are presented to clarify the proposed design procedure and to preliminarily explore the effect on the pressure profile of simple shape errors.

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23

Mirsalimov, V. M. y P. E. Akhundova. "Minimization of contact pressure for hub–shaft friction pair". Journal of Friction and Wear 36, n.º 5 (septiembre de 2015): 404–8. http://dx.doi.org/10.3103/s1068366615050116.

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24

Citarella, R. y S. Gerbino. "BE analysis of shaft–hub couplings with polygonal profiles". Journal of Materials Processing Technology 109, n.º 1-2 (febrero de 2001): 30–37. http://dx.doi.org/10.1016/s0924-0136(00)00772-x.

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25

Dörr, Florian, Michael Funk, Mathias Liewald, Hansgeorg Binz y Robin Köstlmeier. "Influence of Internal Hub Profile on Joining Process of Shaft-hub-connection by Lateral Extrusion". Procedia Engineering 81 (2014): 1988–93. http://dx.doi.org/10.1016/j.proeng.2014.10.269.

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26

Santus, Ciro, L. Bertini y M. Beghini. "Fretting Fatigue Apparatus for Shrink-Fitted Shaft Assembly". Applied Mechanics and Materials 7-8 (agosto de 2007): 43–48. http://dx.doi.org/10.4028/www.scientific.net/amm.7-8.43.

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The present paper proposes a new test rig to perform fretting fatigue tests on a shrinkfitted shaft assembly. A shrink-fitted shaft is put under rotating bending by means of an eccentric offset at one end. The shaft is driven near to its first resonance condition to significantly reduce the required force to produce bending. Test parameters are the imposed bending stress amplitude, and the hub radial pressure obtained through conical fitting. The proposed apparatus allows for changing bending stress amplitude and hub pressure to generate fretting fatigue tests at different conditions. In particular, the role of slip amplitude in fretting fatigue can be investigated. At the present stage the proposed apparatus is under construction at the Mechanical Department of the University of Pisa.

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27

Glovnea, Marilena y Cornel Suciu. "Modeling of Strain and Stress States for Straight Rods with Particular Cross Sections Subjected to Torsion". Advanced Materials Research 837 (noviembre de 2013): 699–704. http://dx.doi.org/10.4028/www.scientific.net/amr.837.699.

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In the case of shaft-hub joints with cylindrical pins found in both macro and micro-devices, a longitudinal gutter with an almost half-circular cross section is practiced along the length of the shaft segment. The center of the circular arc is placed on the circular edge of the cross section. The present paper aims to model strain and stress states within such a shaft, when the material elastic properties are known along with shaft segment length and applied torque. Using the MathCad environment, 3D and constant stress level plots were obtained for the distribution of tangential stresses over the cross section. After application of torque, the transverse cross sections shift and become anti-symmetric as illustrated by the obtained 3D and constant strain plots.

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28

Kim, Bumcho y Gunhee Jang. "TuB-2-1 ROBUST SHAFT DESIGN AGAINST SHAFT DEFORMATION IN HUB PRESS-FITTING AND DISK CLAMPING PROCESS OF A 2.5" HDD". Proceedings of JSME-IIP/ASME-ISPS Joint Conference on Micromechatronics for Information and Precision Equipment : IIP/ISPS joint MIPE 2015 (2015): _TuB—2–1–1—_TuB—2–1–3. http://dx.doi.org/10.1299/jsmemipe.2015._tub-2-1-1.

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29

Kleditzsch, Stefan, Michael Lätzer, Birgit Awiszus y Erhard Leidich. "Numerical Investigation of Knurled Shaft-Hub Connections and Especially of the Joining Process". Materials Science Forum 773-774 (noviembre de 2013): 18–27. http://dx.doi.org/10.4028/www.scientific.net/msf.773-774.18.

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Faced with increasing cost pressures, manufacturers need to find new solutions for shaft-hub connections. One example is the knurled interference fit, where a shaft with knurls and interference is pressed in a soft hub with a cylindrical bore. At present the potential of the knurled interference fit is not fully used, because there are no general standards available for the design and for the joining process. But the joining process in particular has an important impact on the join strength. A predominantly forming joining process offers some advantages compared to cutting. Forming allows a clearly higher contact pressure over the groove because of the displacement of the hub material, which leads to greater axial reliability. Also, the natural material structure is preserved by the forming, and this, in combination with the hardening of the hub, should allow a higher transmittable torque. The Finite Element Method is used for detailed investigation of the joining process and the transmission behavior in the axial direction. With this method, the local loads, for example the hardening of the hub over the groove due to the formed join, are investigated as well as further parameter variations (e.g., chamfer angle, interference). Hence, an analytical approach for the determination of the necessary joining force was derived.

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30

Kahn-Jetter, Zella L., Eugene Hundertmark y Suzanne Wright. "Comparison of Torque Transmitting Shaft Connectivity Using a Trilobe Polygon Connection and an Involute Spline". Journal of Mechanical Design 122, n.º 1 (1 de enero de 2000): 130–35. http://dx.doi.org/10.1115/1.533556.

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The results of a finite element analysis of a trilobe polygon shaft connection used as an alternative for a spline for torque transmission is presented. These results are compared to the results of a finite element analysis previously performed on an involute spline. It is shown that the tensile stress in the polygon shaft is significantly smaller than in the involute spline and is smaller than all the other stresses in both the shaft and the hub in the polygon connection. Furthermore, the magnitudes and distributions of the maximum principal compressive stress, the shear stress, and the Von Mises stress are nearly the same on the shaft and the hub. It appears that polygonal connections can be more advantageous than splined connections because of lower stresses and the lack of stress concentrations typical of splines. [S1050-0472(00)00601-2]

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31

Lee, Dong Hyung, Seok Jin Kwon, Jung Won Seo y Won Hee You. "Effects of Hub Contact Shape on Contact Pressure and Fatigue Life in a Press-Fitted Shaft". Materials Science Forum 654-656 (junio de 2010): 1638–41. http://dx.doi.org/10.4028/www.scientific.net/msf.654-656.1638.

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The objective of this study is to clarify the effect of hub contact shape on contact pressure and fatigue life with regard to the selection of a suitable taper design near the end of the fit. A numerical asymmetric-axisymmetric finite element model was developed in order to determine the contact stress state of press-fitted shaft by using four types of tapered contact surfaces on the hub. The variations of fatigue crack initiation life according to the change of tapered contact surfaces on the hub were evaluated by using the Smith-Watson-Topper (SWT) multiaxial fatigue criterion. As the result, comparing with the contact pressure and the fatigue crack initiation life, maximum decrease of contact pressure and maximum increase of fatigue crack initiation life were obtained for the 1/400 m/m tapered hub subjected to a bending load near the fretting fatigue limit. Furthermore, as the change of bending load, the optimal amout of taper in hub which fatigue life gets into maximum is varied. Therefore, we suggest that the best performance, in terms of pressure distribution and fatigue life of press fit, can be obtained by using a proper taper values for the hub element.

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32

You, Xiao Mei, Lei Meng, Ji Shuang Dai y Bang Chun Wen. "Analysis and Optimization on Impeller Assembly Structure". Applied Mechanics and Materials 16-19 (octubre de 2009): 791–95. http://dx.doi.org/10.4028/www.scientific.net/amm.16-19.791.

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Complete contact is often used in assembling wheel hub and shaft which are used in the closed impeller assembly group of large turbine compressor. The interference is usually fixed. In the topic, based on the nonlinear contact theory and FEM, an impeller assembly is studied from finishing assembly to steady state, then the size and distribution of stress of the contact area between wheel hub and shaft is gotten. Then a structural optimization on the assembly is done. The stress distribution is changed reasonably when the structural redundancy is reduced. Then the incidence of shaft bending is reduced effectively and assembling performance of the impeller assembly structure is improved, the results can be used to offer reference for the design and manufacture.

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33

Lu, Xue Long, Jun Sheng Zhao, Xin Zhong Huang y Shuang Yong Wang. "The Radial Fretting Character Research of the Shaft-Hub of Compress Impeller Based on Virtual Orthogonal Experiment". Applied Mechanics and Materials 668-669 (octubre de 2014): 289–93. http://dx.doi.org/10.4028/www.scientific.net/amm.668-669.289.

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A three-dimensional model of as haft-hub of compressor impeller was set up by Pro/E. Based on the ANSYS; the finite element model was established, using the analysis method of combining submodle and paramesh. The shaft-hub of compressor impeller was simulated by virtual orthogonal design optimization method. Based on the fact that there existed radial fretting in the shaft-hub interference fit joint, researching the influence significance order and law of interference, friction coefficient and rotating speed to the maximum unit frictional work , the average friction work and the optimized parameter were obtained. It turned out that the results of the numerical simulation and orthogonal experiment were accurate and reliable, with the friction and wear effectively reduced, certain guiding references to actual assembly process were got.

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34

Posa, A. y R. Broglia. "Influence by the hub vortex on the instability of the tip vortices shed by propellers with and without winglets". Physics of Fluids 34, n.º 11 (noviembre de 2022): 115115. http://dx.doi.org/10.1063/5.0122751.

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Large-eddy simulations on a cylindrical grid consisting of 5 × 109 points are reported on both conventional and winglets propellers with and without a downstream shaft. Comparisons are focused on the influence by the hub vortex on the process of instability of the tip vortices. They demonstrate that in straight ahead conditions, this influence is actually quite limited for both propellers. The presence of the hub vortex at the wake core results in only a slight upstream shift of the instability of the tip vortices. Meanwhile, the development of the instability of the hub vortex is always delayed, compared to that of the tip vortices, and the former keeps coherent further downstream of their breakup. The results of this study highlight that the hub vortex is not a major source of instability of the tip vortices. Therefore, simplified configurations with no hub vortex, often adopted in the literature, can also provide a good approximation of the process of instability of the tip vortices shed by actual propellers. In contrast, the instability of the tip vortices could be the trigger of that of the hub vortex, whose development is slower. Therefore, experimental and computational studies aimed at analyzing the dynamics of the hub vortex should be designed accordingly, extending to further downstream distances.

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35

Wiater, M., G. Chladek y J. Żmudzki. "FEM numerical simulation of contact stresses between driving shaft and hub impeller of fuel pump". Journal of Achievements in Materials and Manufacturing Engineering 113, n.º 1 (1 de julio de 2022): 13–21. http://dx.doi.org/10.5604/01.3001.0016.0941.

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The aim of the work was to test the contact stresses in the model system of the turbine hub cooperating with the fuel pump drive shaft. The hypothesis of the work was that, by means of FEA, it is possible to assess the contact stresses in the materials of the turbine hub and the fuel pump shaft during torque transmission. A turbine with fibre-reinforced polyphenylene sulphide (PPS) composite cooperating with a stainless steel shaft (X46Cr13/1.4034) in a commonly used D-flat shape joint was selected for the experimental research. To assess contact stresses, the CAD model (NX, Siemens) of the entire turbine was limited to the hub area. The drive shaft is supported in accordance with the bearing in the fuel pump, and the possibility of rotation about the axis along the length of the torque-producing magnet is taken away. The system was loaded with a torque of 200 Nmm on the turbine. The turbine hub and shaft were calculated, taking into account the phenomenon of contact detachment or slip at the value of the friction coefficient of 0.1. The pressure transmission area was found in the area at the edge of the flat surface D-flat and on the opposite side of the D-convexity. The contact stresses on the D-flat side reached values close to the composite strength. The studies did not take into account the technological inaccuracies, thermal deformation, local material properties, and wear. The value of the friction coefficient was not measured in realistic conditions with fuel lubrication. FEA has been achieved, which allows to reduce the cost of experimental research. The proposed model allows for further studies of the influence of elasticity of various materials and structures on contact stresses in order to assess wear resistance.

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36

Young, Larry A., David R. Graham y Robert H. Stroub. "Experimental investigation of rotorcraft hub and shaft fairing drag reduction". Journal of Aircraft 24, n.º 12 (diciembre de 1987): 861–67. http://dx.doi.org/10.2514/3.45530.

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37

Luo, Hong Yun, Chun Jiang Liu y Kai Li. "Contacting Model Considerations of Interference Fit for Shaft-Hub System". Advanced Materials Research 118-120 (junio de 2010): 294–98. http://dx.doi.org/10.4028/www.scientific.net/amr.118-120.294.

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In this study, a contacting model was investigated for interference ﬁt shaft–hub system (rotor system) on rotational speed 30000 r/min by finite element method (FEM) which gives more complete and accurate results than the traditional method. 2-d and 3-d FEM contacting models were established first; then the stress distribution and contact state of rotor system which containing four interference ﬁt couples were analyzed with the contacting FEM model system while the rotor system rotates on 30,000r/min. Finally, an optimal design of shrink range of the rotor system above was debated.

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38

Braude, Bernard M. y John S. McLean. "Percutaneous sheath introducer shaft-hub disconnection during pulmonary artery catheterization". Canadian Journal of Anaesthesia 34, n.º 2 (marzo de 1987): 220–22. http://dx.doi.org/10.1007/bf03015356.

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39

Mouâa, Amal, Nor Eddine Laghzale y Abdel-Hakim Bouzid. "Elastic-Plastic Stresses in Shrink Fit with A Solid Shaft". MATEC Web of Conferences 286 (2019): 02001. http://dx.doi.org/10.1051/matecconf/201928602001.

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Shrink fit joining a solid shaft and a cylinder requires an accurate estimate of the residual contact pressure to transmit high powers, as in the case of gas turbines. Such torques require deformations of materials beyond their elastic limits. This paper presents an analytical model that analyses the stresses in a shrink fit assembly consisting of a solid shaft and a cylindrical hub operating in the elastic-plastic range. Assuming the hub to have a nonlinear work-hardening material behavior, the distribution of stresses as functions of the interference, and the effect of geometry on contact pressure and on interference are exhibited. To validate the analytic method, Finite Element Method was used.

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40

Lesniak, S., V. Dudnik, M. Borowy y O. Lesniak. "Strength of multilayer metal joints «shaft-sleeve-hub» of rotorcrafts obtained by plastic deformation". Journal of Physics: Conference Series 2131, n.º 5 (1 de diciembre de 2021): 052015. http://dx.doi.org/10.1088/1742-6596/2131/5/052015.

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Abstract Metal multilayer joints are used in the production and repair of transmission parts and control systems of rotorcrafts with intensively wearing surfaces in the form of smooth closed cylindrical and conical holes. The article describes two types of connections: rolled sleeve - hub and shaft - rolled sleeve - hub. The adhesion strength of the joints depends on the frictional forces that prevent the sleeve from displacing relative to the hub. The traction strength is determined by measuring the pressing force and the torque. It depends on the relative tension. An increase in the force of pressing the joint occurs with an increase in the relative tension of mandrel, in proportion to the hardening of the material. The smaller hub wall thickness leads to the more active effect of its springback to the foundation of contact pressure and an increasing of the traction force. Experiments have shown that the forces and moments of traction depend on the angle of the intake cone and the width of the cylindrical tape of the mandrel.

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41

Kelemen, Laszlo y Jozsef Szente. "Two Mathematical Models for Generation of Crowned Tooth Surface". Scientific World Journal 2014 (2014): 1–6. http://dx.doi.org/10.1155/2014/641091.

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Gear couplings are mechanical components to connect shaft ends and eliminate the misalignments. The most important element of the gear coupling is the hub which is an external gear having crowned teeth. The crowned teeth on the hub are typically produced by hobbing. The resulting tooth surface depends on several parameters. It is influenced by the size of the hob and the feed. In this paper two mathematical models of the crowned tooth surface are introduced for the generation of the idealized tooth surfaces. These are the profile-shifting and the two-parameter enveloping methods. Our aim is to compare the obtained crowned tooth profiles for the two examined models and to investigate the results. From our numerical results, it was found that the two profiles show indistinguishable differences.

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42

Lin, Li Sheng. "The Technique of Centrifugal Load Loading on a Tail Rotor Shaft Fatigue Life Test". Applied Mechanics and Materials 86 (agosto de 2011): 590–93. http://dx.doi.org/10.4028/www.scientific.net/amm.86.590.

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Tail Rotor Shaft (TRS) is a critical part in Helicopter Transmission System, and its loads are very complicated. This tail rotor shaft is made up of Hub and shaft, which incorporate structure design method used. During the flight, tail rotor shaft should suffer a type of large centrifugal load, due to three high-speed circumrotating. And the life of tail rotor shaft should be affected by the centrifugal load. This article discusses a method that considering the complicated structure of a tail rotor shaft, a set of special centrifugal load applying device and multi-load coordination fatigue test technology are used and carried out the centrifugal load applying triumphantly.

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43

Buschenhenke, F., M. Hofmann, T. Seefeld y F. Vollertsen. "Distortion and residual stresses in laser beam weld shaft-hub joints". Physics Procedia 5 (2010): 89–98. http://dx.doi.org/10.1016/j.phpro.2010.08.033.

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44

Mack, W. "Thermal assembly of an elastic-plastic hub and a solid shaft". Archive of Applied Mechanics 63, n.º 1 (1993): 42–50. http://dx.doi.org/10.1007/bf00787908.

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45

Shen, L. J., A. Lohrengel y G. Schäfer. "Plain–fretting fatigue competition and prediction in spline shaft-hub connection". International Journal of Fatigue 52 (julio de 2013): 68–81. http://dx.doi.org/10.1016/j.ijfatigue.2012.11.012.

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46

Бильдюк, Николай Александрович, Алексей Александрович Рак, Наталья Рудольфовна Туркина y Александр Евгеньевич Шашурин. "ANALYSIS OF CARRYING CAPACITY OF COGGED SPLINE CONNECTION OF HUB-SHAFT". ВЕСТНИК ОБРАЗОВАНИЯ И РАЗВИТИЯ НАУКИ РОССИЙСКОЙ АКАДЕМИИ ЕСТЕСТВЕННЫХ НАУК, n.º 4 (15 de diciembre de 2021): 28–34. http://dx.doi.org/10.26163/raen.2021.43.24.003.

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В программном комплексе ANSYS рассчитаны эквивалентные напряжения и перемещения для разных моделей шлицевых соединений. Было установлено, что эвольвентное шлицевое соединение имеет небольшие напряжения в контактной зоне, что продлевает срок его службы. Прямобочное шлицевое соединение имеет наибольшие эквивалентные напряжения и деформации в зоне контакта, такая конструкция может работать при больших моментных и осевых нагрузках, но с невысоким запасом усталостной прочности. In the ANSYS software package, equivalent stresses and displacements are calculated for different models of spline connections. It was found that the involute spline connection has low stresses in the contact area, which prolongs its lifetime. A straight-sided spline connection has the highest equivalent stresses and deformations in the contact zone, such structure can operate at high moment and axial loads, but with a low margin of fatigue strength.

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47

Madokuboye, Asima y Alfred E. Ogbonnaya. "Vibration Analysis of A 3-Bladed Marine Propeller Shaft for 35000DWT Bulk Carrier". European Journal of Engineering Research and Science 4, n.º 10 (19 de octubre de 2019): 78–86. http://dx.doi.org/10.24018/ejers.2019.4.10.914.

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Vibration Analysis of a 3-bladed Marine Propeller shaft for 35000 DWT Bulk Carrier was carried out. The objectives of the analysis were mathematically designing the 3-bladed propeller shaft, carrying out computer aided design of the shaft and numerically performing vibration analysis. The methodology include mathematically designing the marine propeller and the corresponding shaft, manual calculation of the natural frequency of the shaft, using solidworks to design the shaft and numerically performing vibration analysis on the designed shaft using Analysis System (ANSYS) software. Hub (boss) diameter of 0.17m was calculated. The hollow shaft has external and internal diameters of 0.10m and 0.09m respectively. Torques of 202Nm2 and 384.72Nm2 were obtained at the driver and driven shafts respectively. The natural frequency calculated manually was 249Hz while that of the ANSYS was 280Hz which gives an error of 12%. However, the numerical analysis carried out with ANSYS software also showed that a phase difference of 1800 occurs at the frequency of 280Hz which is a signal of possible misalignment of shaft. At this frequency, the displacement of the shaft has a maximum value of 7.87 . Reaction forces from the components of the shaft were also observed to play major role in the vibration of the propeller shaft. These reaction forces, which cause wearing of the stern tube and intermediate bearings due to friction, are represented by phase angles closer to zero degree. Wear due to friction is a major source of shaft misalignment.

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48

Madokuboye, Asima y Alfred E. Ogbonnaya. "Vibration Analysis of A 3-Bladed Marine Propeller Shaft for 35000DWT Bulk Carrier". European Journal of Engineering and Technology Research 4, n.º 10 (19 de octubre de 2019): 78–86. http://dx.doi.org/10.24018/ejeng.2019.4.10.914.

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Vibration Analysis of a 3-bladed Marine Propeller shaft for 35000 DWT Bulk Carrier was carried out. The objectives of the analysis were mathematically designing the 3-bladed propeller shaft, carrying out computer aided design of the shaft and numerically performing vibration analysis. The methodology include mathematically designing the marine propeller and the corresponding shaft, manual calculation of the natural frequency of the shaft, using solidworks to design the shaft and numerically performing vibration analysis on the designed shaft using Analysis System (ANSYS) software. Hub (boss) diameter of 0.17m was calculated. The hollow shaft has external and internal diameters of 0.10m and 0.09m respectively. Torques of 202Nm2 and 384.72Nm2 were obtained at the driver and driven shafts respectively. The natural frequency calculated manually was 249Hz while that of the ANSYS was 280Hz which gives an error of 12%. However, the numerical analysis carried out with ANSYS software also showed that a phase difference of 1800 occurs at the frequency of 280Hz which is a signal of possible misalignment of shaft. At this frequency, the displacement of the shaft has a maximum value of 7.87 . Reaction forces from the components of the shaft were also observed to play major role in the vibration of the propeller shaft. These reaction forces, which cause wearing of the stern tube and intermediate bearings due to friction, are represented by phase angles closer to zero degree. Wear due to friction is a major source of shaft misalignment.

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49

Sanders, Ross H. y Peter C. Owens. "Hub Movement during the Swing of Elite and Novice Golfers". International Journal of Sport Biomechanics 8, n.º 4 (noviembre de 1992): 320–30. http://dx.doi.org/10.1123/ijsb.8.4.320.

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Many golf coaches refer to a focal point or “hub” of a golf swing and encourage players to imagine the clubhead rotating about this point. The purpose of this study was to locate the hub of the swings of elite (handicaps 0–5) and novice golfers. Six novice and six elite players (all male) each performed 10 swings with the 3-wood provided. Motions of reflective markers attached to the vertex and chin of the subject and three points along the shaft of the club were recorded on videotape. The position of the hub at sampled instants during the swing was defined by the intersection of normals to the clubhead path. Among elite players the hub was not fixed and the pattern of hub movement was consistent. The radius of the hub to the clubhead reached a maximum near impact. Novice players tended to achieve maximum radius after impact and the hub patterns were inconsistent.

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50

Sun, Hua. "Optimization Design of the Composite Hub Connection Structure Based on ANSYS Software Technology". Advanced Materials Research 139-141 (octubre de 2010): 1068–72. http://dx.doi.org/10.4028/www.scientific.net/amr.139-141.1068.

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This article through analysing coupler's structure, involute spline's stress situation, the tooth face contact intensity, the tooth root bending strength, the tooth root shearing strength, tooth face wear ability and the external spline reverse and curving bearing capacity carry on the precise computation and the examination, simultaneously a multianalysis bulge tight joint set of structure and the correlation computation examination, has established the shaft bossing compound coupler main spare part structure type. In this article based on the shaft bossing composite construction optimization design is targeted mainly flexibility swelling ring shape to optimize the design, change that flexibility swelling ring cone-cone angle, which makes flexible swelling ring Auxiliary T-twisting greater. In the analysis, it is necessary to use the software ANSYS, through the creation of the shaft bossing composite construction of the parametrization model, a flexible swelling ring cone-cone angle of the design variables and flexibility swelling ring allowable material stress as binding conditions, bulging with flexible support ring-twisting as the objective function of T,right propeller shaft coupler hub composite structure axisymmetric analysis, contact analysis and design optimization, inflation reached a flexible support ring largest T-twisting, work stress does not exceed the allowable material stress, elastic swelling ring-cone angle of the optimal solution.

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