Effect of cage dynamic unbalance on the cage’s dynamic characteristics in high-speed cylindrical roller bearings

2019 ◽  
Vol 71 (10) ◽  
pp. 1125-1135 ◽  
Author(s):  
Yongcun Cui ◽  
Sier Deng ◽  
Haisheng Yang ◽  
Wenhu Zhang ◽  
Rongjun Niu
Keyword(s):  
High Speed ◽  
Analysis Model ◽  
Skew Angle ◽  
Slip Ratio ◽  
Content Type ◽  
Roller Bearings ◽  
Dynamic Performances ◽  
The Relationship ◽  
Cylindrical Roller ◽  
Dynamic Unbalance

Purpose The purpose of this paper is to study the influence of the cage dynamic unbalance on the dynamic performances in cylindrical roller bearings. Design/methodology/approach The dynamic analysis model which considering cage dynamic unbalance is presented, and the relationship between the cage dynamic unbalance and the cage stability, the cage slip ratio and the cage skew angle is investigated. Findings Cage dynamic unbalance has a great effect on the cage stability. The cage dynamic unbalance which in an axial excursion affects the cage characteristics is greater than that only in the radial direction. The cage slip ratio and the cage skew increases with the cage dynamic unbalance, especially with the axial excursion. The non-metal cage is more sensitive to the cage dynamic unbalance than that of the metal cage. Originality/value The analytical method and model can be applied by the bearing engineering designers.

Effect of roller dynamic unbalance on cage stress of high-speed cylindrical roller bearing

2018 ◽  
Vol 70 (9) ◽  
pp. 1580-1589 ◽  
Author(s):  
Yongcun Cui ◽  
Sier Deng ◽  
Yanguang Ni ◽  
Guoding Chen
Keyword(s):  
High Speed ◽  
Roller Bearing ◽  
Radial Clearance ◽  
Analysis Model ◽  
Element Analysis ◽  
Content Type ◽  
Cylindrical Roller Bearing ◽  
The Impact ◽  
Cylindrical Roller ◽  
Dynamic Unbalance

Purpose The purpose of this study is to investigate the effect of roller dynamic unbalance on cage stress. Design/methodology/approach Considering the impact of roller dynamic unbalance, the dynamic analysis model of high-speed cylindrical roller bearing is established. And then the results of dynamic model are used as the boundary conditions for the finite element analysis model of roller and cage to obtain the cage stress. Findings Roller dynamic unbalance affects the contact status between roller and cage pocket and causes the overall increase in cage stress. The most significant impact on cage stress is roller dynamic unbalance in angular direction of roller axis, followed by radial and axial directions. Smaller radial clearance of bearing and a reasonable range of pocket clearance are beneficial to reduce the impact of roller dynamic unbalance on cage stress; the larger cage guide clearance is a disadvantage to decrease cage stress. The impact of roller dynamic unbalance on cage stress under high-speed condition is greater than that in low-speed conditions. Originality/value The research can provide some theoretical guidance for the design and manufacture of bearing in high-speed cylindrical roller bearing.

Theoretische Analyse eines neuen Loslagerkonzepts*/Theoretical analysis of a new floating bearing - The simulated operational behavior of FRB bearings in comparison to reference bearings

2015 ◽  
Vol 105 (05) ◽  
pp. 285-290
Author(s):  
C. Brecher ◽  
M. Fey ◽  
J. Falker
Keyword(s):  
Experimental Investigation ◽  
Theoretical Analysis ◽  
High Speed ◽  
Contact Point ◽  
Ball Bearings ◽  
Roller Bearings ◽  
Cylindrical Roller ◽  
Bearing System

Das Floating-Roller-Ball (FRB)-Lager ist ein Konzept für Radiallager als Loslager für Hochgeschwindigkeits-Motorspindeln, das die Vorteile von Zylinderrollenlagern und angestellten Mehrpunktlagern in einer neuen Wälzkörpergeometrie kombiniert. Zur Auslegung des ersten Prototyps wurde mithilfe eines Berechnungstools das theoretische Betriebsverhalten untersucht. Die Berechnungsergebnisse liefern Randbedingungen als Grundlage zur experimentellen Untersuchung des Lagerkonzepts.   Floating roller ball bearings provide a new floating bearing system for high-speed motor spindles, combining the advantages of both cylindrical roller bearings and elastically mounted multi-contact point bearings in a new roller geometry. To design the first prototype, the operational behavior of the bearing system was analyzed theoretically by a new calculation tool. The results provide the basis for the experimental investigation of the bearing concept.

Effect of links deformation on motion precision of parallel manipulator based on flexible dynamics

2017 ◽  
Vol 44 (6) ◽  
pp. 776-787 ◽  
Author(s):  
Chunxia Zhu ◽  
Jay Katupitiya ◽  
Jing Wang
Keyword(s):  
Parallel Manipulator ◽  
High Speed ◽  
Beam Theory ◽  
Parallel Manipulators ◽  
Dynamic Responses ◽  
Axial Deformation ◽  
Content Type ◽  
High Performing ◽  
Coupling Equations ◽  
The Relationship

Purpose Manipulator motion accuracy is a fundamental requirement for precision manufacturing equipment. Light weight manipulators in high speed motions are vulnerable to deformations. The purpose of this work is to analyze the effect of link deformation on the motion precision of parallel manipulators. Design/methodology/approach The flexible dynamics model of the links is first established by applying the Euler–Bernoulli beam theory and the assumed modal method. The rigid-flexible coupling equations of the parallel mechanism are further derived by using the Lagrange multiplier approach. The elastic energy resulting from spiral motion and link deformations are computed and analyzed. Motion errors of the 3-link torque-prismatic-torque parallel manipulator are then evaluated based on its inverse kinematics. The validation experiments are also conducted to verify the numerical results. Findings The lateral deformation and axial deformation are largest at the middle of the driven links. The axial deformation at the middle of the driven link is approximately one-tenth of the transversal deformation. However, the elastic potential energy of the transversal deformation is much smaller than the elastic force generated from axial deformation. Practical implications Knowledge on the relationship between link deformation and motion precision is useful in the design of parallel manipulators for high performing dynamic responses. Originality/value This work establishes the relationship between motion precision and the amount of link deformation in parallel manipulators.

Skidding research of a high-speed cylindrical roller bearing with beveled cage pockets

2020 ◽  
Vol 72 (7) ◽  
pp. 969-976
Author(s):  
Yanbin Liu ◽  
Zhanli Zhang
Keyword(s):  
Peer Review ◽  
Tilt Angle ◽  
High Speed ◽  
Hydrodynamic Lubrication ◽  
Roller Bearing ◽  
Front Wall ◽  
Dynamics Model ◽  
Content Type ◽  
Cylindrical Roller Bearing ◽  
Cylindrical Roller

Purpose This study aims to uncover the influencing mechanism of the tilt angles of the cage pocket walls of the high-speed cylindrical roller bearing on the bearing skidding. Design/methodology/approach A novel cylindrical roller bearing with the beveled cage pockets was proposed. Using the Hertz contact theory and the elastohydrodynamic and hydrodynamic lubrication formulas, the contact models of the bearing were built. Using the multibody kinematics and the Newton–Euler dynamics theory, a dynamics model of the bearing was established. Using the Runge–Kutta integration method, the dynamics simulations and analysis of the bearing were performed. Findings The simulation results show that the effects of the tilt angles of the front and rear walls of the pocket on the bearing skidding are remarkable. Under a 5° tilt angle of the front wall of the pocket and a 10° tilt angle of the rear wall, the bearing skidding can be effectively decreased in the rotational speed range of 10,000-70,000 r/min. Originality/value In this paper, a novel cylindrical roller bearing with the beveled cage pockets was proposed; a dynamics model of the bearing was established; the influence mechanism of the tilt angles of the front and rear walls of the pocket on the bearing skidding was investigated, which can provide fundamental theory basis for optimizing the pocket. Peer review The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-01-2020-0035/

scholarly journals The relationship between favorable conditions for innovation in technology parks, the innovation produced, and companies’ performance

2018 ◽  
Vol 15 (3) ◽  
pp. 286-302 ◽  
Author(s):  
Lucas Bonacina Roldan ◽  
Peter Bent Hansen ◽  
Domingo Garcia-Perez-de-Lema
Keyword(s):  
Organizational Performance ◽  
Analysis Model ◽  
Content Type ◽  
Practical Support ◽  
Proposed Model ◽  
Technology Parks ◽  
Effective Development ◽  
Favorable Conditions ◽  
The Relationship ◽  
Depth Interviews

PurposeInnovation is today considered a competitive differential for improving the performance of companies, and technology parks are seen as environments with favorable conditions for such innovation. The purpose of this study is to develop a framework for analyzing favorable conditions for innovation in technology parks, the innovations produced and organizational performance.Design/methodology/approachTo this end, the authors conducted bibliographic research and in-depth interviews with managers of companies based at the Tecnopuc Science and Technology Park, and managers of the park itself, to establish practical support for previous theoretical findings.FindingsAs a result, a framework was developed to link the favorable conditions for innovation, and organizational performance.Research limitations/implicationsThe analysis model proposed here synthesizes the contributions made by several scholars on the theme, allowing for a more detailed and integrated interpretation of the phenomenon, namely, the ways through which the effective development of innovation takes place in companies residing in technology parks and the contribution of innovation to the specific performance of companies.Practical implicationsThe use of the proposed framework can help direct park managers’ action towards those relationships or activities that prove to be ineffective in achieving desired goals.Originality/valueThe use of the proposed model in empirical surveys will allow for better understanding of the phenomenon involving the features of technology parks and their effects on innovation and the performance of companies installed there, considering that such parks allow them to access resources with lower transaction costs.

Negative grey relational model and measurement of the reverse incentive effect of fields medal

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Sifeng Liu
Keyword(s):  
Grey Relational Analysis ◽  
Research Output ◽  
Analysis Model ◽  
Content Type ◽  
Relational Analysis ◽  
Fields Medal ◽  
Definition Of ◽  
Grey Relational ◽  
Analysis Models ◽  
The Relationship

PurposeThe purpose of this paper is to construct some negative grey relational analysis models to measure the relationship between reverse sequences.Design/methodology/approachThe definition of reverse sequence has been given at first based on analysis of relative position and change trend of sequences. Then, several different negative grey relational analysis models, such as the negative grey similarity relational analysis model, the negative grey absolute relational analysis model, the negative grey relative relational analysis model, the negative grey comprehensive relational analysis model and the negative Deng’s grey relational analysis model have been put forward based on the corresponding common grey relational analysis models. The properties of the new models have been studied.FindingsThe negative grey relational analysis models proposed in this paper can solve the problem of relationship measurement of reverse sequences effectively. All the new negative grey relational degree satisfying the requirements of normalization and reversibility.Practical implicationsThe proposed negative grey relational analysis models can be used to measure the relationship between reverse sequences. As a living example, the reverse incentive effect of winning Fields Medal on the research output of winners is measured based on the research output data of the medalists and the contenders using the proposed negative grey relational analysis model.Originality/valueThe definition of reverse sequence and the negative grey similarity relational analysis model, the negative grey absolute relational analysis model, the negative grey relative relational analysis model, the negative grey comprehensive relational analysis model and the negative Deng’s grey relational analysis model are first proposed in this paper.

Authentic leadership, person-organization fit and collectivistic orientation: a moderated-mediated model of workplace safety

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Shuzhen Liu ◽  
Fulei Chu ◽  
Ming Guo ◽  
Yuanyuan Liu
Keyword(s):  
High Speed ◽  
Authentic Leadership ◽  
Positive Impact ◽  
Workplace Safety ◽  
Safety Behaviors ◽  
Safety Behavior ◽  
Content Type ◽  
Safety Compliance ◽  
Person Organization Fit ◽  
The Relationship

PurposeWorkplace safety has been a persistent issue for safety-critical organizations. Based on self-verification theory, this study investigates how authentic leadership affects safety behaviors in a collectivistic context.Design/methodology/approachThis research collected 259 matching questionnaires for high-speed railway (HSR) drivers and their supervisors in China. Specifically, HSR drivers were invited to fill in their general perceived authentic leadership, person-organization fit and collectivistic orientation. In addition, their direct supervisors were invited to assess their safety behaviors.FindingsAuthentic leadership exhibits a significant positive impact on safety compliance and safety participation, implying that authentic leadership positively impacts safety behavior. The person-organization fit partially mediated the relationship between authentic leadership and safety behavior (safety compliance and participation). Furthermore, collectivistic orientation moderates the relationship between authentic leadership and person-organization fit.Originality/valueThe findings of this study provide important insights into authentic leadership and person-organization fit for developing effective strategies to improve workplace safety.

Vibration response analysis of high-speed cylindrical roller bearings using response surface method

2020 ◽  
Vol 234 (2) ◽  
pp. 379-392
Author(s):  
Pravajyoti Patra ◽  
V Huzur Saran ◽  
SP Harsha
Keyword(s):  
Response Surface ◽  
Response Surface Method ◽  
High Speed ◽  
Dynamical Behavior ◽  
Roller Bearing ◽  
Interactive Effects ◽  
Response Analysis ◽  
Roller Bearings ◽  
Surface Method ◽  
Cylindrical Roller

The operating clearance in a bearing influences friction, load zone size and fatigue life of a bearing. Hence, an effort is made to investigate the effect of radial internal clearance on the dynamical behavior of a cylindrical roller bearing system with an unbalance present in the system. The differential equations representing the dynamics of the cylindrical roller bearings have been derived using Lagrange’s equations and solved numerically using the fourth-order Runge-Kutta iterative method. The nonlinear vibration signature has been analyzed due to the clearance and the same is represented by various tools like Acceleration-time plots, Poincaré plots and FFT plots. The approximation method is used to calculate the load distribution and deformation of the individual rollers located at a different position in the load zone, for a preloading/interference fit and positive internal clearance. A response surface method is used to analyze the severity involved in the system due to the combined effect of independent variables like rotor speed, radial load, and radial internal clearance. The observations presented here are not only useful to diagnose the bearing health condition with respect to parametric effects but also exhibit their interactive effects on bearing performance.

scholarly journals Experimental Study on the Skidding Damage of a Cylindrical Roller Bearing

Materials ◽  
2020 ◽  
Vol 13 (18) ◽  
pp. 4075 ◽  
Author(s):  
Qing Zhang ◽  
Jun Luo ◽  
Xiang-yu Xie ◽  
Jin Xu ◽  
Zhen-huan Ye
Keyword(s):  
High Speed ◽  
Large Scale ◽  
Failure Modes ◽  
Roller Bearing ◽  
Weight Ratio ◽  
Operating Conditions ◽  
Roller Bearings ◽  
Light Load ◽  
Cylindrical Roller Bearing ◽  
Cylindrical Roller

As large-scale rotating machines develop toward high rotating speed and high power–weight ratio, skidding damage has become one of the major initial failure modes of cylindrical roller bearings. Therefore, understanding the skidding damage law is an effective way to ensure the safety of machines supported by cylindrical roller bearings. To realize the skidding damage, a high-speed rolling bearing test rig that can simulate the actual operating conditions of aviation bearings was used in this paper, and the skidding damage dynamic behaviors of cylindrical roller bearings were investigated. In addition, to ensure the accuracy of the obtained skidding damage mechanism, the cylindrical roller bearing was carefully inspected by microscopic analysis when the skidding damage occurred. Out results show that instantaneous increases in friction torque, vibration acceleration, and temperature are clearly observed when the skidding damage occurs in the cylindrical roller bearing. Furthermore, under the conditions of inadequate lubrication and light load, the critical speed of skidding damage is rather low. The major wear mechanisms of skidding damage include oxidation wear, abrasive wear, and delamination wear. The white layers are found locally in the inner ring and rollers under the actions of friction heat and shear force.

Sign in / Sign up

Export Citation Format

Share Document