Artykuły w czasopismach: „Rolling Contact”

1

Fernandez Rico, J. E., A. Hernandez Battez i D. Garcia Cuervo. "Rolling contact fatigue in lubricated contacts". Tribology International 36, nr 1 (styczeń 2003): 35–40. http://dx.doi.org/10.1016/s0301-679x(02)00097-x.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

2

Kuo, Chang Hung. "Elasto-Plastic Contact Stress Analysis of Hardened Elements under Repeated Contact Loading". Key Engineering Materials 823 (wrzesień 2019): 91–96. http://dx.doi.org/10.4028/www.scientific.net/kem.823.91.

Pełny tekst źródła

Streszczenie:

An elastic-plastic contact stress analysis is presented to study cyclic plastic deformation of surface hardened rolling elements under repeated contacts. The rolling contact is simulated by a Hertz contact loading moving across an elastic-plastic half-space. An exponential model with hardness varying with depth is employed for the surface hardened components, and the Chaboche nonlinear hardening rule is used to model cyclic plastic behavior of contact elements. Numerical results show that the hardened layer can effectively reduce the plastic deformation near contact surface. The contact elements with sufficient surface hardness may reach elastic shakedown state under repeatedly rolling contact. As the hardened layer reaches a certain depth, e.g. two times of half contact length, however, the effects of case depth on plastic strain and residual stress become negligible after hundred contact cycles.

Style APA, Harvard, Vancouver, ISO itp.

3

Dubina, Radek, i Jan Eliáš. "Effect of Rolling Resistance in Dem Models With Spherical Bodies". Transactions of the VŠB – Technical University of Ostrava, Civil Engineering Series. 16, nr 2 (1.12.2016): 11–18. http://dx.doi.org/10.1515/tvsb-2016-0009.

Pełny tekst źródła

Streszczenie:

Abstract The rolling resistance is an artificial moment arising on the contact of two discrete elements which mimics resistance of two grains of complex shape in contact rolling relatively to each other. The paper investigates the influence of rolling resistance on behaviour of an assembly of spherical discrete elements. Besides the resistance to rolling, the contacts between spherical particles obey the Hertzian law in normal straining and Coulomb model of friction in shear.

Style APA, Harvard, Vancouver, ISO itp.

4

YASHIKI, Takuya, Tekehiro MORITA, Yoshinori SAWAE i Tetsuo YAMAGUCHI. "Transonic rolling / sliding contact". Proceedings of Mechanical Engineering Congress, Japan 2018 (2018): J0420203. http://dx.doi.org/10.1299/jsmemecj.2018.j0420203.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

5

Dumitrascu, Alina Corina, Gelu Ianus i Dumitru Olaru. "Influence of the Contact Pressure on the Rolling Resistance Moments in Dry Ball-Race Contacts". Applied Mechanics and Materials 658 (październik 2014): 305–10. http://dx.doi.org/10.4028/www.scientific.net/amm.658.305.

Pełny tekst źródła

Streszczenie:

Based on a theoretical model and an experimental methodology for defining the rolling resistance moments in a modified thrust ball bearing having only 3 balls, the authors experimentally investigated the influence of the Hertzian contact pressure on rolling resistance moments between a ball and a race. The experiments were realized with balls having diameters between 1.588 mm and 4.762 mm with maximum Hertzian pressure between 0.2GPa and 1GPa, operating for rotational speed between 60rpm to 210 rpm. The experiments evidenced that the measured values of the rolling resistance moments have higher values that the theoretical hysteresis and curvature rolling resistance moments for low contact pressure. By increasing of the contact pressure to 1GPa the experimental values for rolling resistance moments are in good agreement with the theoretical models.

Style APA, Harvard, Vancouver, ISO itp.

6

Chang, L., Yongwu Zhao, P. B. Hall, R. Thom i C. Moore. "On Heat Generation in Rolling Contacts Under Boundary and Mixed Lubrication". Journal of Tribology 123, nr 1 (17.08.2000): 61–66. http://dx.doi.org/10.1115/1.1330733.

Pełny tekst źródła

Streszczenie:

This paper reports on experiments and theoretical analyses of heat generation and scuffing failure in rolling contacts. The experiments were conducted with dry contacts, and the theoretical analyses were carried out using a deterministic thermal contact model. The research reveals that heat generated by asperity plastic deformation in the direction normal to the contact can be significant in high-load, high-speed contacts under boundary and mixed lubrication conditions. Under near rolling conditions, heat generated by the plastic deformation largely dominates that by the friction and is the main source leading to contact scuffing. This heat generation is shown to be significant compared to frictional heating even at relatively large slide-to-roll ratios. Parametric studies show that the ratio of asperity-plastic-deformation heating to frictional heating is sensitive to slide-to-roll ratio, hardness and surface finish but insensitive to contact load, rolling velocity and fluid/asperity load sharing.

Style APA, Harvard, Vancouver, ISO itp.

7

Loewenthal, S. H. "Spin Analysis of Concentrated Traction Contacts". Journal of Mechanisms, Transmissions, and Automation in Design 108, nr 1 (1.03.1986): 77–84. http://dx.doi.org/10.1115/1.3260788.

Pełny tekst źródła

Streszczenie:

Spin, the result of a mismatch in contact radii on either side of the point of rolling, has a detrimental effect on traction contact performance. It occurs in concentrated contacts having conical or contoured rolling elements, such as those in traction drives or angular contact bearings, and is responsible for an increase in contact heating and power loss. This investigation examines the kinematics of spin-producing contact geometries and the subsequent effect on traction and power loss. The influence of lubricant traction characteristics and contact geometries that minimize spin are also addressed.

Style APA, Harvard, Vancouver, ISO itp.

8

Patzer, Gregor, Mathias Woydt, Raj Shah, Curtis Miller i Philip Iaccarino. "Test Modes for Establishing the Tribological Profile under Slip-Rolling". Lubricants 8, nr 5 (25.05.2020): 59. http://dx.doi.org/10.3390/lubricants8050059.

Pełny tekst źródła

Streszczenie:

The complex nature of slip-rolling contacts in many applications such as gear tooth flanks, rolling bearings, and heavy machinery often makes determining the friction and wear properties, as well as the fatigue resistance, of tribosystems difficult. The establishment of the tribological profile of a tribocouple under high Hertzian contact pressure and under slip-rolling will allow for the measurement and comparison of friction and wear coefficients as well as slip-rolling resistance by continuously monitoring the wear rate, coefficient of friction, temperature, oil film thickness, and/or electrical contact resistance using high-resolution signal analysis (HRA). A twin disc system can provide insight into the adhesive behavior of material and lubricant products such as alternative base oils and additives, ceramics, alloys, and thin film coatings. The strength and endurance of these products are often characterized through fatigue and resistance tests, which apply high Hertzian contact pressures to the rolling contact until seizure or failure is obtained. The further observation of the formation of tribofilms on the surface of contact yields information about the reactivity and thermochemical properties of additives. This review aims to illustrate how the implementation of different screening methodologies can be used as a meaningful tool for assessing the aforementioned tribological profile properties for the development of slip-rolling tribosystems.

Style APA, Harvard, Vancouver, ISO itp.

9

Nishida, Shin-ichi, Nobusuke Hattori i Tsubasa Miyake. "OS11W0289 Study on contact rolling fatigue of rails". Abstracts of ATEM : International Conference on Advanced Technology in Experimental Mechanics : Asian Conference on Experimental Mechanics 2003.2 (2003): _OS11W0289. http://dx.doi.org/10.1299/jsmeatem.2003.2._os11w0289.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

10

Wirsching, Sven, i Marcel Bartz. "Using exact macroscopic geometry in elastohydrodynamic simulations of point and elliptical contacts". Tribologie und Schmierungstechnik 69, nr 5-6 (15.02.2023): 54–61. http://dx.doi.org/10.24053/tus-2022-0045.

Pełny tekst źródła

Streszczenie:

In rib-guided roller bearings, there are a large number of different tribological contact forms. These include not only line contacts on the raceways, the cage and the rolling elements, but also point and elliptical contacts between the rolling element end face and the ring rib. Load is transmitted via these lubricated, concentrated rolling and rolling-sliding contacts. Depending on the load situation, these contacts contribute differently to the operating behavior of the roller bearing. Axial loads on rib-guided roller bearings are mainly transmitted via the point and elliptical contacts between the roller end and the ring rib. These oil-lubricated point and elliptical contacts can be calculated and designed using thermos-elastohydrodynamic (TEHD) simulations. In existing methods for the TEHD calculation of point and elliptical contacts, the macroscopic geometries of the contact partners are described in a simplified manner, similar to the theory according to HERTZ, using ellipsoids. However, contacts of real, complex geometry pairings of rolling elements and ribs, as used to optimize the axial load capacity or the frictional torque of roller bearings, can only be determined inaccurately with this method. Compared to the exact consideration of the macroscopic geometry, larger discrepancies in the lubricant film height, contact pressure and friction can be observed. For this reason, this paper presents a TEHD simulation that considers the exact macroscopic geometry of point or elliptical contacts. The macroscopic geometry is generated using mathematical functions and a ray-tracing method is used to generate the equivalent body for the TEHD simulation. Different geometry pairings of sphere, plane, cone and torus are investigated. The results for lubricant film height, contact pressure and friction are compared with the results from conventional TEHD simulations, which use a geometry description via ellipsoids. By comparing the calculated geometry pairings, the possibilities and limitations of the modified geometry description are assessed.

Style APA, Harvard, Vancouver, ISO itp.

11

Bhargava, V., G. T. Hahn i C. A. Rubin. "An Elastic-Plastic Finite Element Model of Rolling Contact, Part 1: Analysis of Single Contacts". Journal of Applied Mechanics 52, nr 1 (1.03.1985): 67–74. http://dx.doi.org/10.1115/1.3169028.

Pełny tekst źródła

Streszczenie:

This paper describes a two-dimensional (plane strain) elastic-plastic finite element model of rolling contact that embodies the elastic-perfectly plastic, cycle and amplitude-independent material of the Merwin and Johnson theory, but is rigorous with respect to equilibrium and continuity requirements. The rolling contact is simulated by translating a semielliptical pressure distribution. Both Hertzian and modified Hertzian pressure distributions are used to estimate the effect of plasticity on contact width and the continuity of the indentor-indentation interface. The model is tested for its ability to reproduce various features of the elastic-plastic indentation problem and the stress and strain states of single rolling contacts. This paper compares the results derived from the finite element analysis of a single, frictionless rolling contact at p0/k = 5 with those obtained from the Merwin and Johnson analysis. The finite element calculations validate basic assumptions made by Merwin and Johnson and are consistent with the development of “forward” flow. However, the comparison also reveals significant differences in the distribution of residual stress and strain components after a single contact cycle.

Style APA, Harvard, Vancouver, ISO itp.

12

Biboulet, N., L. Houpert i AA Lubrecht. "Contact stress and rolling contact fatigue of indented contacts: Part I, numerical analysis". Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology 227, nr 4 (12.11.2012): 310–18. http://dx.doi.org/10.1177/1350650112462954.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

13

Juettner, Michael, Marcel Bartz, Stephan Tremmel i Sandro Wartzack. "On the Transient Effects at the Beginning of 3D Elastic-Plastic Rolling Contacts for a Circular Point Contact Considering Isotropic Hardening". Lubricants 10, nr 3 (19.03.2022): 47. http://dx.doi.org/10.3390/lubricants10030047.

Pełny tekst źródła

Streszczenie:

In a three-dimensional transient simulation of the elastic–plastic rolling contact, transient effects can be observed at the beginning of the rolling until a stationary state is reached after rolling for a length of several times the contact radius. In most cases, the steady-state regime is in focus of scientific investigations, whereas the transient effects are hardly considered. In the present work, those transient effects at the beginning of a frictionless rolling contact of a rigid sphere on an elastic–plastic plane are studied in detail. The analysis is limited to isotropic strain hardening. In particular, the changes of the contact pressure during rolling, as well as the plastic strain state and plastic deformations remaining after rolling are investigated. This is intended to get to the bottom of existing explanatory approaches from literature, which are based on the change in conformity. Beyond that, a more profound explanation of the transient effects is developed by identifying existing correlations.

Style APA, Harvard, Vancouver, ISO itp.

14

Mokhtar, M. O. A., i A. A. Abdel-Ghany. "Elastohydrodynamic Behavior of Rolling Elliptical Contacts: Part II: Oil Film Thickness and Contact Profile". Journal of Tribology 107, nr 3 (1.07.1985): 352–57. http://dx.doi.org/10.1115/1.3261075.

Pełny tekst źródła

Streszczenie:

A spherically crowned circular disk in contact with a mating plain cylindrical one has been used in a two disk machine to conduct elastohydrodynamic (EHD) investigations with the contact zone describing elliptical shape. The oil film thickness variation has been accurately measured and herein presented under several contact situations with disks running with either pure rolling or combined rolling and sliding motion. Results confirmed that the introduction of a percentage slip over a rolling contact by either changing disks relative speed or skewing disks axes relative to each other, would affect the resultant oil film thickness by reducing it. However, the contact profile retained its shape with a mean oil film passage followed by a reduction at the trailing exit end. Compared with previous EHD theoretical and experimental findings, the present results come in line with previous predictions and confirm the importance of adopting thermal solutions in solving EHD situations.

Style APA, Harvard, Vancouver, ISO itp.

15

Ahmed, R., i M. Hadfield. "Rolling contact fatigue behaviour of thermally sprayed rolling elements". Surface and Coatings Technology 82, nr 1-2 (lipiec 1996): 176–86. http://dx.doi.org/10.1016/0257-8972(95)02736-x.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

16

Beer, O. "Nitriding of Rolling Contact Races". HTM Journal of Heat Treatment and Materials 74, nr 5 (10.10.2019): 317–30. http://dx.doi.org/10.3139/105.110392.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

17

Chue, C. H., i H. H. Chung. "Pitting formation under rolling contact". Theoretical and Applied Fracture Mechanics 34, nr 1 (sierpień 2000): 1–9. http://dx.doi.org/10.1016/s0167-8442(00)00019-7.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

18

Sosnovskiy, L. A., i S. S. Sherbakov. "Vibro-impact in rolling contact". Journal of Sound and Vibration 308, nr 3-5 (grudzień 2007): 489–503. http://dx.doi.org/10.1016/j.jsv.2007.04.031.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

19

TAKEHARA, Koh. "Traction of Rolling Contact Drives". Journal of the Society of Mechanical Engineers 88, nr 805 (1985): 1361–66. http://dx.doi.org/10.1299/jsmemag.88.805_1361.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

20

Meged, Y. "Cavitation in Rolling Contact Bearings". Materials Performance and Characterization 6, nr 1 (1.12.2017): 20170023. http://dx.doi.org/10.1520/mpc20170023.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

21

Kalker, J. J. "Wheel-rail rolling contact theory". Wear 144, nr 1-2 (kwiecień 1991): 243–61. http://dx.doi.org/10.1016/0043-1648(91)90018-p.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

22

Bogacz, R., J. Roňda i M. Brzozowski. "Corrugations in Rolling Contact Problems". ZAMM - Journal of Applied Mathematics and Mechanics / Zeitschrift für Angewandte Mathematik und Mechanik 67, nr 11 (1987): 567–68. http://dx.doi.org/10.1002/zamm.19870671110.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

23

BRACCIALI, A., i G. CASCINI. "ROLLING CONTACT FORCE ENERGY RECONSTRUCTION". Journal of Sound and Vibration 236, nr 2 (wrzesień 2000): 185–92. http://dx.doi.org/10.1006/jsvi.1999.2533.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

24

MIURA, Tetsuya, Atsushi MATSUBARA, Daisuke KONO, Iwao YAMAJI, Kazuma OTAKA i Kaoru HOSHIDE. "Influence of Rolling Contact Surface and Contact Load on Fluctuation of Rolling Friction Force". Journal of the Japan Society for Precision Engineering 84, nr 1 (5.01.2018): 97–102. http://dx.doi.org/10.2493/jjspe.84.97.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

25

Brock, Louis. "Rolling contact with slip on a thermoelastic half-space: comparison with perfect rolling contact". Journal of Mechanics of Materials and Structures 3, nr 3 (1.05.2008): 493–506. http://dx.doi.org/10.2140/jomms.2008.3.493.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

26

Seo, Jung-Won, Hyun-Kyu Jun, Seok-Jin Kwon i Dong-Hyeong Lee. "Rolling contact fatigue and wear of two different rail steels under rolling–sliding contact". International Journal of Fatigue 83 (luty 2016): 184–94. http://dx.doi.org/10.1016/j.ijfatigue.2015.10.012.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

27

Ivanov, A. P. "On rolling friction". Доклады Академии наук 485, nr 3 (21.05.2019): 295–99. http://dx.doi.org/10.31857/s0869-56524853295-299.

Pełny tekst źródła

Streszczenie:

The dependence of rolling friction on velocity for various contact conditions is discussed. The principal difference between rolling and other types of relative motion (sliding and spinning) is that the points of the body in contact with the support change over time. Due to deformations, there is a small contact area and, entering into contact, the body points have a normal velocity proportional to the diameter of this area. For describing the dependence of the friction coefficient on the angular velocity in the case of “pure” rolling, a linear dependence is proposed that admits a logical explanation and experimental verification. Under the combined motion, the rolling friction retains its properties, the sliding and spinning friction acquiring the properties of viscous friction.

Style APA, Harvard, Vancouver, ISO itp.

28

Zhou, R. S., H. S. Cheng i T. Mura. "Micropitting in Rolling and Sliding Contact Under Mixed Lubrication". Journal of Tribology 111, nr 4 (1.10.1989): 605–13. http://dx.doi.org/10.1115/1.3261984.

Pełny tekst źródła

Streszczenie:

Based on morphological tests in rolling and sliding contact, the effect of surface film, the subsurface heavily dislocated layer, crack initiation, crack propagation, and micropitting have been investigated by using a two-disk rig. A micro-macro contact model is presented for surface pitting in rolling and sliding contacts. In this model the pressures related to asperity interaction and the subsurface stress map along whole contact area have been analyzed by superimposing the asperity contacting loads on the Hertzian load for a given specimen surface. Compared to the experimental results, this model is capable of predicting the onset of micropits for given mechanical and lubrication conditions. Cracking is assumed to occur when the accumulated strain energy of the dislocation reaches a critical value. A three-dimensional crack propagating model has also been used for pitting life prediction in rolling and sliding contact.

Style APA, Harvard, Vancouver, ISO itp.

29

Wen, Zefeng, Xuesong Jin i Yanyao Jiang. "Elastic-Plastic Finite Element Analysis of Nonsteady State Partial Slip Wheel-Rail Rolling Contact". Journal of Tribology 127, nr 4 (21.06.2005): 713–21. http://dx.doi.org/10.1115/1.2033898.

Pełny tekst źródła

Streszczenie:

A finite element analysis with the implementation of an advanced cyclic plasticity theory was conducted to study the elastic-plastic deformation under the nonsteady state rolling contact between a wheel and a rail. The consideration of nonsteady state rolling contact was restricted to a harmonic variation of the wheel-rail normal contact force. The normal contact pressure was idealized as the Hertzian distribution, and the tangential force presented by Carter was used. Detailed rolling contact stresses and strains were obtained for repeated rolling contact. The harmonic variation of the normal (vertical) contact force results in a wavy rolling contact surface profile. The results can help understand the influence of plastic deformation on the rail corrugation initiation and growth. The creepage or stick-slip condition greatly influences the residual stresses and strains. While the residual strains and surface displacements increased at a reduced rate with increasing rolling passes, the residual stresses stabilize after a limited number of rolling passes. The residual stresses and strains near the wave trough of the residual wavy deformation are higher than those near the wave crest.

Style APA, Harvard, Vancouver, ISO itp.

30

Datta, J., i K. Farhang. "A Nonlinear Model for Structural Vibrations in Rolling Element Bearings: Part I—Derivation of Governing Equations". Journal of Tribology 119, nr 1 (1.01.1997): 126–31. http://dx.doi.org/10.1115/1.2832445.

Pełny tekst źródła

Streszczenie:

This paper, the first of two companion papers, presents a model for investigating structural vibrations in rolling element bearings. The analytical formulation accounts for tangential and radial motions of the rolling elements, as well as the cage, the inner and the outer races. The contacts between the rolling elements and races are treated as nonlinear springs whose stiffnesses are obtained by application of the equation for Hertzian elastic contact deformation. The derivation of the equations of motion is facilitated by assuming that only rolling contact exists between the races and rolling elements. Application of Lagrange’s equations leads to a system of nonlinear ordinary differential equations governing the motion of the bearing system. These equations are then solved using the Runge-Kutta integration technique. Using the formulation in the second part—“A Nonlinear Model for Structural Vibrations in Rolling Element Bearings: Part II—Simulation and Results,” a number of effects on bearing structural vibrations are studied. This work is unique from previous studies in that the model simulates vibration from intrinsic properties and constituent elements of the bearing, and takes into account every contact region within the bearing, representing it by a nonlinear spring.

Style APA, Harvard, Vancouver, ISO itp.

31

Arimoto, Suguru, i Morio Yoshida. "A Mathematical and Numerically Integrable Modeling of 3D Object Grasping under Rolling Contacts between Smooth Surfaces". Modelling and Simulation in Engineering 2011 (2011): 1–8. http://dx.doi.org/10.1155/2011/684034.

Pełny tekst źródła

Streszczenie:

A computable model of grasping and manipulation of a 3D rigid object with arbitrary smooth surfaces by multiple robot fingers with smooth fingertip surfaces is derived under rolling contact constraints between surfaces. Geometrical conditions of pure rolling contacts are described through the moving-frame coordinates at each rolling contact point under the postulates: (1) two surfaces share a common single contact point without any mutual penetration and a common tangent plane at the contact point and (2) each path length of running of the contact point on the robot fingertip surface and the object surface is equal. It is shown that a set of Euler-Lagrange equations of motion of the fingers-object system can be derived by introducing Lagrange multipliers corresponding to geometric conditions of contacts. A set of 1st-order differential equations governing rotational motions of each fingertip and the object and updating arc-length parameters should be accompanied with the Euler-Lagrange equations. Further more, nonholonomic constraints arising from twisting between the two normal axes to each tangent plane are rewritten into a set of Frenet-Serre equations with a geometrically given normal curvature and a motion-induced geodesic curvature.

Style APA, Harvard, Vancouver, ISO itp.

32

Jiang, Zheng Yi, Hai Bo Xie, L. M. Yang, Hong Tao Zhu, Dong Bin Wei i A. Kiet Tieu. "Mechanics of Asymmetric Rolling of Thin Strip with Effect of Work Roll Edge Contact". Materials Science Forum 561-565 (październik 2007): 115–18. http://dx.doi.org/10.4028/www.scientific.net/msf.561-565.115.

Pełny tekst źródła

Streszczenie:

Asymmetric rolling of thin strip has become important due to a significant decrease of rolling force, which contributes to obtain the extremely thin strip, to reduce the rolling passes, and to save the energy by a decrease of anneal treatment. In asymmetric rolling of thin strip, edges of work rolls may contact and deform when no or small work roll bending force is applied. Work roll edge contact forms a new deformation feature. In this paper, the effects of initial thickness of strip and friction coefficient on the rolling pressure, roll edge contact length and strip crown during asymmetric rolling of thin strip with work roll edge contact effect has been discussed, and the calculated rolling force with work roll edge contact is compared with the measured value.

Style APA, Harvard, Vancouver, ISO itp.

33

Tomaraee, Parviz, Aref Mardani, Arash Mohebbi i Hamid Taghavifar. "Relationships among the contact patch length and width, the tire deflection and the rolling resistance of a free-running wheel in a soil bin facility". Spanish Journal of Agricultural Research 13, nr 2 (29.05.2015): e0211. http://dx.doi.org/10.5424/sjar/2015132-5245.

Pełny tekst źródła

Streszczenie:

<p>Qualitative and quantitative analysis of contact patch length-rolling resistance, contact patch width-rolling resistance and tire deflection-rolling resistance at different wheel load and inflation pressure levels is presented. The experiments were planned in a randomized block design and were conducted in the controlled conditions provided by a soil bin environment utilizing a well-equipped single wheel-tester of Urmia University, Iran. The image processing technique was used for determination of the contact patch length and contact patch width. Analysis of covariance was used to evaluate the correlations. The highest values of contact length and width and tire deflection occurred at the highest wheel load and lowest tire inflation pressure. Contact patch width is a polynomial (order 2) function of wheel load while there is a linear relationship between tire contact length and wheel load as well as between tire deflection and wheel load. Correlations were developed for the evaluation of contact patch length-rolling resistance, contact patch width-rolling resistance and tire deflection-rolling resistance. It is concluded that the variables studied have a significant effect on rolling resistance.</p>

Style APA, Harvard, Vancouver, ISO itp.

34

Sun, Wei, Xiangxi Kong, Bo Wang i Xingzhan Li. "Statics modeling and analysis of linear rolling guideway considering rolling balls contact". Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 229, nr 1 (17.04.2014): 168–79. http://dx.doi.org/10.1177/0954406214531943.

Pełny tekst źródła

Streszczenie:

The linear rolling guideway is composed of rail, carriage, rolling balls, and other accessories and contains a large number of rolling interfaces between the rolling balls and the grooves. For such a complex nonlinear mechanical system, it is very significant to obtain the statics deformation and vertical stiffness under different loads for the structural design of guideway and mechanical analysis of Computer Numerical Control (CNC) machine tool. Therefore, the focus of this study is on the development of statics modeling techniques of the linear rolling guideway by analytical and finite element methods, considering the rolling balls contact. First, an accurate statics analytical modeling method was proposed by using the Hertz contact theory and revision of experiment results. Then, on the basis of considering contacts between rolling balls and grooves, the precise finite element modeling was studied. To improve the efficiency of analysis, the full finite element model of guideway was replaced by the component finite element model. At last, the created analytical and component finite element models were applied to analyze the effects of load and preload on the statics characteristics of single ball and the whole guideway system. The proposal of current study may provide a reference to create the precise dynamics model of linear rolling guideway.

Style APA, Harvard, Vancouver, ISO itp.

35

Tolcha, Mesay, i Holm Altenbach. "Numerical Modeling Rolling Contact Problem and Elasticity Deformation of Rolling Die under Hot Milling". Metals 9, nr 2 (13.02.2019): 226. http://dx.doi.org/10.3390/met9020226.

Pełny tekst źródła

Streszczenie:

In metalworking, rolling is a metal-forming process in which slab is passed through one or more pairs of the rolling dies to reduce the thickness and to make the thickness uniform. Modeling of rolling die contact with the slab primarily needs to describe the Tribology of contact phenomena. The central concern of numerical modeling is used in this work to indicate a set of equations, derived from the contact principle, that transfer the physical event into the mathematical equations. Continuum rolling contact phenomena is considered to explain how a contact region is formed between rolling die and slab and how the tangential force is distributed over the contact area with coefficient of friction. At the end, elasticity stress behavior of rolling die contact with the slab for a number of cyclic loads is modeled. The model includes new proposed constitutive equations for discontinuity of the velocity–pressure distribution in rolling contact from the entry side to exit side of the neutral point. To verify the model, finite element simulation and experimental data from the literature are considered. The results show good agreement with finite element simulation and experimental data.

Style APA, Harvard, Vancouver, ISO itp.

36

Wang, Wen Jian, Qing Fei Zeng, Jun Guo i Qi Yue Liu. "Study on Rolling Contact Behaviors of Three Kinds of Railway Wheel Treads". Advanced Materials Research 118-120 (czerwiec 2010): 151–55. http://dx.doi.org/10.4028/www.scientific.net/amr.118-120.151.

Pełny tekst źródła

Streszczenie:

The rolling contact behaviors between LMA, S1002 and XP55 wheelset and track in static rolling contact are analyzed using the rolling contact theory of three-dimensional elastic bodies with non-Hertz form and numerical program of CONTACT. The numerical results indicate that three kinds of wheel treads have different difference of rolling radius and equivalent taper. The rolling contact behaviors between three kinds of wheel treads and CHN60 rail have obvious difference. The comprehensive analysis indicates that the matching effect of LAM wheel tread and CHN60 rail is relatively superior. Furthermore, it is suggested that new wheel tread should be designed and optimized for the high-speed railway.

Style APA, Harvard, Vancouver, ISO itp.

37

Ghalme, Sachin G. "Probabilistic Life Models in Rolling Contact Fatigue". Advanced Materials Research 433-440 (styczeń 2012): 58–62. http://dx.doi.org/10.4028/www.scientific.net/amr.433-440.58.

Pełny tekst źródła

Streszczenie:

Rolling contact fatigue (RCF) is the name given to crack growth and material damage generated as a result of high loads transmitted between two surfaces which are rolling with relative to each other. An understanding of rolling contact fatigue failure mechanism and a prediction of lifetimes are of interest to both manufacturer and researcher. Subsurface originated cracks have been recognized as one of the main modes of failure for rolling contact fatigue (RCF) of bearings. Numbers of investigators have attempted to determine the physical mechanism involved in rolling contact fatigue of bearings and proposed models to predict their fatigue lives. This paper attempts to cover the most widely used probabilistic life models used in RCF.

Style APA, Harvard, Vancouver, ISO itp.

38

Wang, Guangqiu, i K. Knothe. "Stress Analysis for Rolling Contact Between Two Viscoelastic Cylinders". Journal of Applied Mechanics 60, nr 2 (1.06.1993): 310–17. http://dx.doi.org/10.1115/1.2900794.

Pełny tekst źródła

Streszczenie:

The two-dimensional viscoelastic rolling contact with Coulomb’s dry friction is considered for steady-state rolling. A so-called standard linear solid (three parameter model) is used to characterize the viscoelastic material behavior. Rolling contact stresses between two rolling cylinders are investigated by a boundary element method, based on the half-space theory. Numerical results are presented including the stress distribution at the contact surfaces and in viscoelastic bodies as well as rolling resistance.

Style APA, Harvard, Vancouver, ISO itp.

39

Howell, M. B., C. A. Rubin i G. T. Hahn. "The Effect of Dent Size on the Pressure Distribution and Failure Location in Dry Point Frictionless Rolling Contacts". Journal of Tribology 126, nr 3 (28.06.2004): 413–21. http://dx.doi.org/10.1115/1.1692053.

Pełny tekst źródła

Streszczenie:

Finite element simulation is performed for rolling contact over four different size spherical dents. Two rolling contacts are simulated using a portion of a sphere as a counter-face to the dented half-space. The effect of dent size on the pressure distribution and fatigue failure location for dry point contact is studied. The material model used was adjusted to match both the stress amplitude versus strain range curve and ratchetting experimental data for 52100 bearing steel.

Style APA, Harvard, Vancouver, ISO itp.

40

Shu, Xue Dao, De Yi Liu i Guang Xian Shen. "Analyzing Rolling Pressure of Rolling Strip by Multi-Object Contact Multi-Pole Boundary Element Method". Advanced Materials Research 428 (styczeń 2012): 14–18. http://dx.doi.org/10.4028/www.scientific.net/amr.428.14.

Pełny tekst źródła

Streszczenie:

For guiding production effectively and revealing rolling mechanisms, the analysis of rolling-pressure distribution regulation is very important. Because rolling strip belongs to multi-object contact engineering problem which involves coupling deformation, obviously the accuracy of disaggregate mathematical method is low. Therefore, in this paper,it is developed that multi-object, elasto-plastic and frictional contact multipole Boundary Element Method (BEM) by Fortran program. It can simulate five object synchronous contact accurately without artificial assumption.The three dimensional rolling-pressure distribution regulation of rolling strip has been obtained through this program. Through testing and calculating the load properties of bearing, the result shows that it is accordant for test and calculation. Therefore, multi-pole BEM is one of the effective numerical analytic tools of rolling contact problem, and the obtained result of rolling-pressure distribution can provide for reference value for analyzing rolling strip.

Style APA, Harvard, Vancouver, ISO itp.

41

Sandu-Ville, Florin Tudose. "Jacq Effect Influence on Thermomechanical Contact Fatigue". Applied Mechanics and Materials 658 (październik 2014): 377–80. http://dx.doi.org/10.4028/www.scientific.net/amm.658.377.

Pełny tekst źródła

Streszczenie:

The paper take into account the thermo – mechanical contact fatigue as an important component of global thermo – mechanical contact wear. This phenomenon is very important for contacts localized in enclosure, working non – stop, with few possibilities of intervention. It is presented in a synthetical way the theories concerning the location of the decisive stresses for mechanical rolling contact fatigue in connection with the primary crack in deterioration . Also, are made some considerations about the thermal effect Jacq and the consequences for the temperature gradient in a metallic wall. Most of the technological processes are carried out with heat release. An illustrated example is the rolling mill process where the thermal tide is at a high level. The reability evaluation for rolling mill rollers it is in connection with the position of the primary crack under the contact surface. This position give the type of the decisive stress for destruction. The importance of the paper is the connection between the thermal effect Jacq and the thermomechanical contact fatigue. Also, the influence of the changing slope for the temperature gradient concerning the position of the primary crack under the contact surface in thermomechanical contact fatigue [1].

Style APA, Harvard, Vancouver, ISO itp.

42

Nikas, George K. "Particle extrusion in elastohydrodynamic line contacts: Dynamic forces and energy consumption". Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology 231, nr 10 (16.02.2017): 1320–40. http://dx.doi.org/10.1177/1350650117693175.

Pełny tekst źródła

Streszczenie:

The author’s model of particle entrapment and thermoviscoplastic indentation built and experimentally validated in recent publications is utilised to calculate the contact forces on ductile, isolated interference particles passing through elastohydrodynamic, rolling–sliding, line contacts. The model is detailed and enriched by supplementary equations. A parametric study deals with the effects of particle size and cold hardness, kinetic friction coefficient, rolling velocity and slide-to-roll ratio of the contact on the particle contact forces, mean friction coefficient, temperature, plastic work and power required to deform a particle, as well as on dent volume and plastic strain rates of the indented contact surfaces. A factual selection of optimal conditions and parameter values that minimise the disruption of a contaminated contact is thus greatly facilitated.

Style APA, Harvard, Vancouver, ISO itp.

43

Seo, Jung Won, Hyun Kyu Jun, Seok Jin Kwon i Dong Hyeong Lee. "Rolling Contact Fatigue and Wear Behavior of Rail Steel under Dry Rolling-Sliding Contact Condition". Advanced Materials Research 891-892 (marzec 2014): 1545–50. http://dx.doi.org/10.4028/www.scientific.net/amr.891-892.1545.

Pełny tekst źródła

Streszczenie:

Rolling contact fatigue and wear of rails are inevitable problems for railway system due to wheel and rail contact. Increased rail wear and increased fatigue damage such as shelling, head check, etc. require more frequent rail exchanges and more maintenance cost. The fatigue crack growth and wear forming on the contact surface are affected by a variety of parameters, such as vertical and traction load, friction coefficient on the surface. Also, wear and crack growth are not independent, but interact on each other. Surface cracks are removed by wear, which can be beneficial for rail, however too much wear shortens the life of rail. Therfore, it is important to understand contact fatigue and wear mechanism in rail steels according to a variety of parameters. In this study, we have investigated fatigue and wear characteriscs of rail steel using twin disc testing. Also the comparative wear behavior of KS60 and UIC 60 rail steel under dry rolling-sliding contact was performed.

Style APA, Harvard, Vancouver, ISO itp.

44

Fujii, Masahiro, Akira Yoshida, Jiabin Ma, Sadato Shigemura i Kazumi Tani. "Rolling contact fatigue of alumina ceramics sprayed on steel roller under pure rolling contact condition". Tribology International 39, nr 9 (wrzesień 2006): 856–62. http://dx.doi.org/10.1016/j.triboint.2005.07.038.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

45

Kulkarni, S. M., G. T. Hahn, C. A. Rubin i V. Bhargava. "Elasto-Plastic Finite Element Analysis of Repeated Three-Dimensional, Elliptical Rolling Contact With Rail Wheel Properties". Journal of Tribology 113, nr 3 (1.07.1991): 434–41. http://dx.doi.org/10.1115/1.2920643.

Pełny tekst źródła

Streszczenie:

This paper presents an elasto-plastic analysis of the repeated, frictionless, three-dimensional rolling contact similar to the ones produced by the rail-wheel geometry. This paper treats an elliptical contact rolling across a semi-infinite half space. The contact shape and loading: semi-major axis (in the rolling direction), w1 = 8 mm, and semi-minor axis, w2 = 5.88 mm, reflect standard rail and wheel curvatures and a wheel load of 149 KN (33,000 lb). A three-dimensional, elasto-plastic finite element model, developed earlier, is employed together with the elastic-linear-kinematic-hardening-plastic (ELKP) idealization of the cyclic plastic behaviour of a material similar to rail and wheel steels. The calculations present the displacements, the stress-strain distributions, stress-plastic strain histories and the plastic strain ranges in the half-space. The cyclic plasticity approaches a steady state after one contact with further contacts producing open but fully reversed stress-strain hysteresis loops, i.e., plastic shakedown.

Style APA, Harvard, Vancouver, ISO itp.

46

Lv, Peng, Changling Tian, Yujun Xue, Yongjian Yu, Haichao Cai i Yanjing Yin. "Finite Element Analysis of Damage Evolution of Solid Lubrication Film in Rolling–Sliding Contact". Lubricants 12, nr 7 (18.07.2024): 258. http://dx.doi.org/10.3390/lubricants12070258.

Pełny tekst źródła

Streszczenie:

Based on the cohesive zone model (CZM), a finite element model of the film–substrate bearing system in the rolling–sliding contact state is established. Through analyzing the normal and tangential bearing states of the film–substrate system, the effects of the sliding–rolling ratio and the film–substrate adhesion strength on the interfacial stress and the interfacial energy release rate of the film–substrate system are studied. The results show that there is an almost symmetric stress distribution at both sides of the contact zone in rolling contact. In rolling–sliding contact, obvious shear flow along the rolling–sliding direction occurs at the front edge of the contact zone, which results in a significant increase in the shear stress at the interface at the front edge of the contact zone, increasing the risk of interface damage and delamination failure. Meanwhile, the shear flow causes a normal tensile stress concentration along the film surface behind the contact zone, which very easily causes the emergence and expansion of the film surface cracks. In addition, there is a clear positive correlation between the adhesion strength and the load-bearing capacity of the film–substrate interface. The tangential delamination damage mainly occurs at the interface regardless of the rolling or rolling–sliding contact state.

Style APA, Harvard, Vancouver, ISO itp.

47

Cabezas, Sebastian, György Hegedűs i Péter Bencs. "Thermal contact resistance for stationary and moving heat sources in angular contact ball bearings". Tribology and Materials 2, nr 3 (2023): 99–107. http://dx.doi.org/10.46793/tribomat.2023.015.

Pełny tekst źródła

Streszczenie:

Sliding friction is a common tribological effect that occurs between the contact surfaces of the inner components (inner race, outer race and balls) of a spindle rolling bearing during operation. This friction generally generates heat, which can affect the performance of the rolling bearing. To date, numerous studies have assumed that the contact surface between the inner components of the bearing is circular and stationary. While this assumption has yielded adequate results, it is not sufficient in the case of angular contact ball bearings, where the contact surfaces are elliptical and could be treated as either stationary or moving heat sources. This paper presents solutions for both, stationary and moving heat sources for elliptical contact surfaces in a spindle rolling bearing. The primary objective is to find the thermal contact resistances which are dependent on the shape of contact, the loads, the rotational speed and the material properties thereof, applying the mathematical expressions developed by Muzychka and Yovanovich. These expressions were used to calculate various thermal resistances, providing results applicable to the analysis of thermal models in spindle rolling elements. Through finite element analysis (FEA) performed in Ansys Workbench, the stationary and moving heat sources were compared, finding the heat distribution along the elements of the bearing. The findings herein are suitable for the creation of thermal networks in rolling bearings, which are essential to predict their thermal behaviour.

Style APA, Harvard, Vancouver, ISO itp.

48

Guo, Baoliang, Wenlong Wu, Jianxiao Zheng, Yumin He i Jinhua Zhang. "Dynamics Modeling and Analysis of Rolling Bearings Variable Stiffness System with Local Faults". Machines 11, nr 6 (2.06.2023): 609. http://dx.doi.org/10.3390/machines11060609.

Pełny tekst źródła

Streszczenie:

By analyzing the support of load-carrying rolling elements when the rolling elements fall into the fault position, the dynamics model of a rolling bearing variable stiffness system with local faults is proposed, considering the retention factor of the contact deformation. Then, this paper researches the change of effective contact stiffness, contact deformation, contact force, and the total effective stiffness of the rolling elements. The results show that the contact stiffness of the rolling elements abruptly decreases when the rolling elements fall into the fault position. The contact deformation and contact force of the load-carrying rolling elements in the load zone increase, rebalancing the external radial load while causing a sudden reduction in the total effective stiffness, resulting in the vibration of the system. When different rolling elements fall into the outer ring fault position, the change in total effective stiffness and the system response are equal in magnitude. Additionally, there is a significant outer race fault characteristic frequency accompanied by frequency multiplication in the fault characteristic spectrums. When different rolling elements fall into the inner race fault position, the total effective stiffness is modulated by the inner race rotation and varies dramatically, resulting in the amplitude of the system time domain vibration response also being modulated by the inner race rotation and varying dramatically. Additionally, there is a significant inner race rotational frequency accompanied by frequency multiplication, an inner race fault characteristic frequency accompanied by frequency multiplication, and a side frequency in the fault characteristic spectrums. The research can provide some reference for the effective diagnosis of the rolling bearing fault.

Style APA, Harvard, Vancouver, ISO itp.

49

Olver, A. V., i D. Dini. "Roughness in lubricated rolling contact: The dry contact limit". Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology 221, nr 7 (1.07.2007): 787–91. http://dx.doi.org/10.1243/13506501jet318.

Pełny tekst źródła

Streszczenie:

A difficulty with the standard fast Fourier transform (FFT) perturbation model of roughness in lubricated rolling contacts is that it does not necessarily converge towards the elastic case as the film thickness is reduced; rather it leads to a situation in which all the roughness is completely flattened. This is rarely the case for real engineering surfaces. Here, it is shown that this difficulty can be avoided by carrying out a Fourier transform of the elastostatically flattened roughness and using the resulting (complex) amplitude as the low-film thickness limit of each Fourier component in the elastohydrodynamic lubrication (EHL) analysis. Results give a plausible convergence to the elastostatic solution, which is nevertheless consistent with the expected near-full-film EHL behaviour and which becomes identical to the earlier model for roughness that, statically, can be fully flattened. As expected, hydrodynamic action persists at the finest scale, even for very thin films.

Style APA, Harvard, Vancouver, ISO itp.

50

M, Dmytrychenko, Savchuk A i Hlukhonets A. "FEATURES OF LUBRICANE LAYER CREATING IN A LOCAL CONTACT". National Transport University Bulletin 1, nr 48 (2021): 135–42. http://dx.doi.org/10.33744/2308-6645-2021-1-48-135-142.

Pełny tekst źródła

Streszczenie:

The article presents the results of research of the influence of the rolling speed parameter during pure rolling and 20% rolling with slip on the kinetics of formation of the lubricant layer thickness in the central contact zone. The aim of experimental research is establishing the impact of operational parameters of friction pairs - speed rolling (a pure rolling and 20% rolling with slip) the dynamics of the process of forming the lubricant layer thickness in the central contact zone between contacting surfaces experimental «steel ball - glass disc.» Oils of various operational purpose were used in the research work, namely motor oils for gasoline and diesel engines (М8Г2К, М10Г2К), universal motor oil (SAE15w40LUX) and universal motorgear oils (ЄМТ-8, ЄМТ ПРОТЕК) (I-40). The increase in rolling speed was shifted from 0 to 1.8 m / s; at a volumetric temperature (об'ємній температурі) of oils 20°С; contact stress of 251.5 MPa. The thickness lubricating layer in contact was determined by optical interferometry. According to the results of experimental researches concerning determination of the lubricating action of oils in different composition and operational purpose, it was found that during the period of friction steam kinetics of the formation of the lubricant layer thickness depends on the rolling speed - with the increase of which there is an increase in the lubricant layer thickness in the central contact zone, leading to the establishment of appropriate lubrication modes (from boundary to hydrodynamic). Decisive role kinematic viscosity of the lubricant, which depends on the base of oils and quantitative content of the additives. Based on the experimental data obtained in conditions of the rolling with slip, favorable conditions for reducing the initial rolling speed by setting the maximum lubrication regime when using lubricant which contained surfactants with polar molecules. KEY WORDS: ELASTOHYDRODYNAMIC CHARACTERISTICS, ROLLING SPEED, CLEAN ROLLING, SUSPENSION ROLLING, THICKNESS OF THE LUBRICATION LAYER

Style APA, Harvard, Vancouver, ISO itp.

Artykuły w czasopismach na temat „Rolling Contact”

Utwórz poprawne odniesienie w stylach APA, MLA, Chicago, Harvard i wielu innych