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Article
Publication date: 2 August 2019

Yongcun Cui, Sier Deng, Haisheng Yang, Wenhu Zhang and Rongjun Niu

The purpose of this paper is to study the influence of the cage dynamic unbalance on the dynamic performances in cylindrical roller bearings.

Abstract

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.

Details

Industrial Lubrication and Tribology, vol. 71 no. 10
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 4 May 2020

Yanbin Liu and Zhanli Zhang

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.

Abstract

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/

Details

Industrial Lubrication and Tribology, vol. 72 no. 7
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 8 January 2018

Sier Deng, Jinfang Gu, Yongcun Cui and Wenhu Zhang

This study aims to analyze the roller dynamic characteristics and cage whirling of tapered roller bearing considering roller tilt and skew which provide a theoretical basis for…

Abstract

Purpose

This study aims to analyze the roller dynamic characteristics and cage whirling of tapered roller bearing considering roller tilt and skew which provide a theoretical basis for the design and application of tapered roller bearing.

Design/methodology/approach

Based on rolling bearing dynamic analysis, the dynamic differential equations of tapered roller bearing are established. Fine integral method and predict correct Adams–Bashforth–Moulton multi-step method are used to solve the dynamic differential equations of tapered roller bearings.

Findings

Friction at the flange contact between roller and large flange is the chief factor of roller skew. In comparison to cone speed, axial loads have more visible effect on roller skew, and proper speed or axial load is beneficial to sustain cage motion and decrease cage instability. Under the combined effort of axial load and radial load, the distribution of roller skew is correlated to the roller-flange contact load. In addition, roller skew angle in loaded zone is larger than that in unloaded zone; hence, it is helpful for cage stability if an extent radial load is applied. The pocket clearance of cage has very small influence on roller skew; therefore, a reasonable pocket clearance is suggested to assure minimum instability of cage. Friction coefficient of flange contact has a large effect on roller skew, and cage whirl is found to demonstrate a circular orbit with increasing friction coefficient.

Originality/value

The dynamic differential equations of tapered roller bearing considering roller large end/inner ring back face rib contact under various lubrication states were established. The impact of flange friction working conditions and cage pocket clearance on cage instability and roller skew were focused on. It is the first time that the ratio of the standard deviation of the cage-center translational speed to its mean value is used to access the instability of cage in tapered roller bearing.

Details

Industrial Lubrication and Tribology, vol. 70 no. 1
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 13 April 2020

Hui Li, Heng Liu, Hao Li, Shemiao Qi, Yi Liu and Fengtao Wang

The purpose of this paper is to investigate the effect of the cage-pocket wear on the dynamic behavior of the ball bearing.

Abstract

Purpose

The purpose of this paper is to investigate the effect of the cage-pocket wear on the dynamic behavior of the ball bearing.

Design/methodology/approach

Through analyzing the complicated relationship and interactions among the ball bearing elements, the dynamic modeling of the ball bearing was established considering the gravity, drag force from the oil, hydrodynamic effect on the cage and the dynamic simulations with different amounts of the cage-pocket wear loss of the ball bearing (BPWL) were obtained by solving the ball bearing dynamic equations using Runge–Kutta method.

Findings

The results show that the trajectory of the cage’s centroid presents two vibration modes with different amplitudes. In addition, those two different forms of trajectory of different amplitudes emerge alternatively with BPWL increase moreover the diameter of the trajectory decrease significantly with the BPWL increasing, which is consistent with the experimental result and last BPWL has lightly effect on the average skidding ratio of the cage, however, the BPWL would produce significant effects on the fluctuation of the skidding ratio, which can directly reflect the stability of motion to a certain extent.

Originality/value

Practice shows that the bearing failure resulting from the cage accounts for 25 per cent of the total failure of the rolling bearings. However, few discussions about how the wear of the cage-pocket would influence the dynamic characteristics of the cage. This study can provide important ideas for the design of bearing cage-pocket size and the fault identification of the ball bearing to decrease the failure rate caused by the cage.

Peer review

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-12-2019-0535/

Details

Industrial Lubrication and Tribology, vol. 72 no. 7
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 25 August 2022

Yanling Zhao and Chuanwang Wu

This paper uses numerical methods to investigate the collision and skidding of rolling elements in a cageless ball bearing. This paper aims to analyse the effects of the…

Abstract

Purpose

This paper uses numerical methods to investigate the collision and skidding of rolling elements in a cageless ball bearing. This paper aims to analyse the effects of the rotational speed and number of rolling elements on the rolling element collision and skidding.

Design/methodology/approach

Based on Hertzian theory and tribological theory, the collision contact model of the rolling element was established. Based on the proposed model, the differential equations of motion of the two degrees of freedom rolling element were constructed. The fourth-order Adams algorithm solved the collision contact force between the rolling elements. The sliding velocity between the rolling element and the inner and outer races was calculated.

Findings

The collision frequency and slip of rolling elements can be reduced by increasing the rotational speed appropriately and reducing the number of rolling elements by one.

Originality/value

The developed model can reveal the collision and slip characteristics of the rolling elements for cageless bearings. This study can provide theoretical guidance for the design and manufacture of cageless ball bearings.

Details

Industrial Lubrication and Tribology, vol. 74 no. 9
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 29 August 2019

Zhen Li, Yufan Lu, Chi Zhang, Jinlong Dong, Xiaoli Zhao and Liqin Wang

The traction behaviours of lubricating oil significantly affect the stability and lubrication regime of aviation high-speed ball bearings. Rolling elements will slide at a low…

Abstract

Purpose

The traction behaviours of lubricating oil significantly affect the stability and lubrication regime of aviation high-speed ball bearings. Rolling elements will slide at a low traction force (TF). Therefore, traction behaviours need to be studied, and a fitting expression for traction curves to rapidly calculate the traction coefficient (TC) should be developed.

Design/methodology/approach

The traction behaviours of an aviation lubricating oil were studied in severe operating conditions with a self-designed two-disc testing rig. Based on the least squares method and the Levenberg–Marquardt theory, a rapid calculation expression was developed by fitting the obtained traction curves. The correction of this expression was experimentally verified by comparing the TCs under different operating conditions. This expression was also used to modify the commonly accepted quasi-dynamic model of rolling bearings.

Findings

An increase of the load led to an increase in the TC. In comparison, the temperature and entrainment speed showed inverse effects. The proposed expression exactly predicted the trend of the experimentally acquired traction curve. The calculation with the modified dynamic model showed that the action of the TF on a single rolling element varied and that the temperature increase of the outer raceway is higher than the inner raceway, which is caused by the TF and relative sliding speed between the elements and raceways.

Originality/value

The proposed fitting expression is able to simplify the TC calculation of synthetic aviation lubricating oil in practical engineering applications. This paper can provide an important reference for the traction behaviour of synthetic aviation lubricating oil under severe conditions and assist with its rapid calculation and practical application in engineering.

Details

Industrial Lubrication and Tribology, vol. 72 no. 1
Type: Research Article
ISSN: 0036-8792

Keywords

Abstract

FOR a number of years now it has been evident that a successor to the well‐tried Vickers Viscount and Convoir 240/340/440 series was required. However, the big problem was to design an aircraft such that its economics and passengerappealweresub‐stantially better than the machines it would ultimately replace. Other important factors which had to be con‐sidered were improved reliability, easier and cheaper maintenance, higher standards of safety and means of reducing ramp times. Furthermore, the difficult choice of passenger capacity and cruising speed had to be made. Probably the easiest decision was to employ the twin‐engine configuration with the power plants placed in the now familiar rear position, one on cither side of the fuselage.

Details

Aircraft Engineering and Aerospace Technology, vol. 35 no. 5
Type: Research Article
ISSN: 0002-2667

Article
Publication date: 5 October 2018

Yongcun Cui, Sier Deng, Yanguang Ni and Guoding Chen

The purpose of this study is to investigate the effect of roller dynamic unbalance on cage stress.

Abstract

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.

Details

Industrial Lubrication and Tribology, vol. 70 no. 9
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 14 November 2023

Qiang Bian, Xiangyun Zhang, Bowen Jiao, Guang Zeng and Chunjiang Zhao

The purpose of this paper is to establish a dynamic analysis model of composite cylindrical roller bearings, investigate the effects of different working conditions on the…

Abstract

Purpose

The purpose of this paper is to establish a dynamic analysis model of composite cylindrical roller bearings, investigate the effects of different working conditions on the kinematic characteristics of composite bearings and compare the differences between them and solid roller bearings.

Design/methodology/approach

This paper establishes a dynamic analysis model for composite cylindrical roller bearings and proves the correctness of the established model by establishing dynamic vibration experiments and contact theory for composite roller bearings. Comparative analysis was conducted on the effects of coupling changes in rotational speed, load, number of rollers and filling ratio on parameters such as bearing static stiffness, contact stress and vibration acceleration.

Findings

The composite roller can enhance the bearing’s operational stability and minimize contact stress, but that a higher filling ratio is going to increase the bearing’s stiffness. The acceleration degree of bearing vibration, the load on the outer raceway nodes and the bearing stability all decrease as inner ring speed rises.

Originality/value

A dynamic calculation model of composite cylindrical roller bearings is established, and the influence of multiparameter coupling changes on bearing vibration and contact is studied, which lays a foundation for the structural improvement of the bearings.

Details

Industrial Lubrication and Tribology, vol. 75 no. 10
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 18 October 2018

Zuhao Li, Chenyu Wang, Chen Li, Zhonghan Wang, Fan Yang, He Liu, Yanguo Qin and Jincheng Wang

This paper aims to review the latest applications in terms of three-dimensional printed (3DP) metal implants in orthopedics, and, importantly, the design of 3DP metal implants…

576

Abstract

Purpose

This paper aims to review the latest applications in terms of three-dimensional printed (3DP) metal implants in orthopedics, and, importantly, the design of 3DP metal implants through a series of cases operated at The Second Hospital of Jilin University were presented.

Design/methodology/approach

This paper is available to practitioners who are use 3DP implants in orthopedics. This review began with the deficiency of traditional prostheses and basic concepts of 3DP implants. Then, representative 3DP clinical cases were summarized and compared, and the experiences using customized prostheses and directions for future potential development are also shown.

Findings

The results obtained from the follow-up of clinical applications of 3DP implants show that the 3D designed and printed metal implants could exhibit good bone defect matching, quick and safe joint functional rehabilitation as well as saving time in surgery, which achieved high patient satisfaction collectively.

Originality/value

Single center experiences of 3DP metal implants design were shared and the detailed technical points between various regions were compared and analyzed. In conclusion, the 3DP technology is infusive and will present huge potential to reform future orthopedic practice.

Details

Rapid Prototyping Journal, vol. 24 no. 8
Type: Research Article
ISSN: 1355-2546

Keywords

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