Service Life of Lubricating Grease in Ball Bearings (Part 1) Behavior of Grease and Its Base Oil in a Ball Bearing

Abstract As a new high-end bearing product, full ceramic ball bearings are favoured in a variety. However, there have been few studies on the lubrication of full ceramic ball bearings. The purpose of this study is to reveal the relationship between the vibration and temperature rise of full ceramic angular contact ball bearings and the lubricant viscosity, and to improve the service life of the bearings. In this study, the effects of lubricant viscosity on the vibration and temperature rise of silicon nitride full ceramic angular contact ball bearings under different axial loads and rotation speeds were tested. Herein, a mathematical model of oil lubrication suitable for full ceramic ball bearings is established and the relationship between the lubricant viscosity, lubricant film thickness, outer ring vibration and temperature rise of the bearing is analyzed. It was found that the vibration and temperature rise first decrease and then increase with the increase of lubricant viscosity. In this range, there is an optimal viscosity value to minimize the vibration and temperature rise of the full ceramic angular contact ball bearing. The contact surface wear of the full ceramic angular contact ball bearing varies greatly under different lubricant viscosities. There is no obvious wear on the contact surface under optimal viscosity, and the service life of the bearing is greatly improved. These results can play an important role in revealing the lubricant mechanism of full ceramic ball bearings and improving their service life under optimal lubrication.

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Ferrofluid lubrication for ball bearings to avoid starvation

Industrial Lubrication and Tribology ◽

10.1108/ilt-04-2020-0132 ◽

2020 ◽

Vol 72 (10) ◽

pp. 1227-1231

Author(s):

Mancheng Xu ◽

Guanghu Jin ◽

Qingwen Dai ◽

Wei Huang ◽

Xiaolei Wang

Keyword(s):

Magnetic Field ◽

Service Life ◽

Peer Review ◽

Design Methodology ◽

Ball Bearing ◽

Magnetic Circuit ◽

Ball Bearings ◽

Rolling Bearings ◽

Content Type ◽

Circuit Structure

Purpose This paper aims to prevent oil starvation and improve the service life of the rolling bearings. Design/methodology/approach A thrust ball bearing with magnetic circuit structure is proposed for ferrofluid lubrication. With the aid of magnetic field, ferrofluid can be maintained in the contact area of rolling bodies to delay lubricant loss. Experiments are performed to ensure the validity of the designed bearing. Findings Compared with conventional lubricant, service life of the ferrofluid lubricated bearing can be prolonged under magnetic field. In addition, with a proper magnetic field distribution, lubricant starvation may be limited under the conditions of present experiments. Originality/value This work provides a method to control the starved lubrication of rolling bearings with restricted lubricant supply. Peer review The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-04-2020-0132/

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Temperature Rise Prediction of Oil-Air Lubricated Angular Contact Ball Bearings Using Artificial Neural Network

Recent Patents on Mechanical Engineering ◽

10.2174/2212797612666190530115739 ◽

2019 ◽

Vol 12 (3) ◽

pp. 248-261

Author(s):

Baomin Wang ◽

Xiao Chang

Keyword(s):

Neural Network ◽

Artificial Neural Network ◽

Temperature Rise ◽

High Speed ◽

Ball Bearing ◽

Influence Factors ◽

Ball Bearings ◽

Ann Model ◽

Angular Contact Ball Bearing ◽

Artificial Neural

Background: Angular contact ball bearing is an important component of many high-speed rotating mechanical systems. Oil-air lubrication makes it possible for angular contact ball bearing to operate at high speed. So the lubrication state of angular contact ball bearing directly affects the performance of the mechanical systems. However, as bearing rotation speed increases, the temperature rise is still the dominant limiting factor for improving the performance and service life of angular contact ball bearings. Therefore, it is very necessary to predict the temperature rise of angular contact ball bearings lubricated with oil-air. Objective: The purpose of this study is to provide an overview of temperature calculation of bearing from many studies and patents, and propose a new prediction method for temperature rise of angular contact ball bearing. Methods: Based on the artificial neural network and genetic algorithm, a new prediction methodology for bearings temperature rise was proposed which capitalizes on the notion that the temperature rise of oil-air lubricated angular contact ball bearing is generally coupling. The influence factors of temperature rise in high-speed angular contact ball bearings were analyzed through grey relational analysis, and the key influence factors are determined. Combined with Genetic Algorithm (GA), the Artificial Neural Network (ANN) model based on these key influence factors was built up, two groups of experimental data were used to train and validate the ANN model. Results: Compared with the ANN model, the ANN-GA model has shorter training time, higher accuracy and better stability, the output of ANN-GA model shows a good agreement with the experimental data, above 92% of bearing temperature rise under varying conditions can be predicted using the ANNGA model. Conclusion: A new method was proposed to predict the temperature rise of oil-air lubricated angular contact ball bearings based on the artificial neural network and genetic algorithm. The results show that the prediction model has good accuracy, stability and robustness.

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Friction Tests of Ball Bearings with Comparison of Lubricants

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.866.375 ◽

2017 ◽

Vol 866 ◽

pp. 375-378

Author(s):

Sathitbunanan Sumate ◽

Wirote Ritthong

Keyword(s):

Energy Efficiency ◽

Electric Power ◽

Ball Bearing ◽

Maximum Load ◽

Engine Oil ◽

Ball Bearings ◽

Hydraulic Oil ◽

Proper Size ◽

Transmission Fluid ◽

Moving Parts

The ball bearings are the rotating components which are widely spread to moving parts for all machinery operation in general industry. This paper presents the ball bearing resistance tool which has a proper size and can handle the maximum load of 300 kg by using an electric power. The ball bearing resistance tool was used to test the bearings No. 6011 cm. The series of tests was performed in the ball bearings lubricated; engine oil SAE 10W/40, auto transmission fluid Dexron, and hydraulic oil. The rotational speeds for testing were vary; 500, 600 and 700 rpm respectively. At each speed, there were various weight; 50, 70, 90,110,130,150, and 170 kg respectively. The results show that the hydraulic oil generated the smallest coefficients of friction and energy efficiency for ball bearing operation.

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Preload-service life correlation for ball bearings on machine tool main spindles

Wear ◽

10.1016/0043-1648(94)90302-6 ◽

1994 ◽

Vol 172 (1) ◽

pp. 79-83 ◽

Cited By ~ 14

Author(s):

G.D. Hagiu ◽

M.D. Gafitanu

Keyword(s):

Service Life ◽

Machine Tool ◽

Ball Bearings

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Prediction of Ball Motion in High-Speed Thrust-Loaded Ball Bearings

Journal of Lubrication Technology ◽

10.1115/1.3452889 ◽

1976 ◽

Vol 98 (3) ◽

pp. 463-469 ◽

Cited By ~ 14

Author(s):

C. R. Gentle ◽

R. J. Boness

Keyword(s):

Computer Program ◽

High Speed ◽

Ball Bearing ◽

Viscoelastic Behavior ◽

Specific Situation ◽

Fluid Models ◽

Ball Bearings ◽

Theoretical Predictions ◽

Ball Motion

This paper describes the development of a computer program used to analyze completely the motion of a ball in a high-speed, thrust-loaded ball bearing. Particular emphasis is paid to the role of the lubricant in governing the forces and moments acting on each ball. Expressions for these forces due to the rolling and sliding of the ball are derived in the light of the latest fluid models, and estimates are also made of the cage forces applicable in this specific situation. It is found that only when lubricant viscoelastic behavior is considered do the theoretical predictions agree with existing experimental evidence.

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Study of the Stiffness Matrix of Preloaded Duplex Angular Contact Ball Bearings

Journal of Tribology ◽

10.1115/1.4041895 ◽

2018 ◽

Vol 141 (3) ◽

Cited By ~ 7

Author(s):

Shengye Lin ◽

Shuyun Jiang

Keyword(s):

Stiffness Matrix ◽

Degrees Of Freedom ◽

Ball Bearing ◽

Ball Bearings ◽

Fixed Position ◽

Angular Contact Ball Bearing ◽

Face To Face ◽

Radial Stiffness ◽

Proposed Model ◽

Stiffness Characteristics

This paper studies the stiffness characteristics of preloaded duplex angular contact ball bearings. First, a five degrees-of-freedom (5DOF) quasi-static model of the preloaded duplex angular contact ball bearing is established based on the Jones bearing model. Three bearing configurations (face-to-face, back-to-back, and tandem arrangements) and two preload mechanisms (constant pressure preload and fixed position preload) are included in the proposed model. Subsequently, the five-dimensional stiffness matrix of the preloaded duplex angular contact ball bearing is derived analytically. Then, an experimental setup is developed to measure the radial stiffness and the angular stiffness of duplex angular contact ball bearings. The simulated results match well with those from experiments, which prove the validity of the proposed model. Finally, the effects of bearing configuration, preload mechanism, and unloaded contact angle on the angular stiffness and the cross-coupling are studied systematically.

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The influence of base oil type on the rheological properties of ecological lubricating greases

Nafta-Gaz ◽

10.18668/ng.2021.02.07 ◽

2021 ◽

Vol 77 (2) ◽

pp. 127-135

Author(s):

Rafał Kozdrach ◽

Keyword(s):

Shear Stress ◽

Shear Rate ◽

Rheological Properties ◽

Measurement Data ◽

Measuring System ◽

Rheological Parameters ◽

Flow Curves ◽

Lubricating Grease ◽

Dispersion Phase ◽

Base Oil

The article presents the results of research on the influence the type of base oil in lubricating compositions has on the rheological parameters of selected lubricants. Vegetable, mineral, and synthetic dispersion phases were used to produce lubricating greases. The modified amorphous silica was used as the dispersed phase. However, as a modifying additive was used a substance containing the antioxidants, corrosion inhibitors, and EP/AW additives. The experiments on rheological properties were carried out using a Physica MCR 101 rotational rheometer (manufactured by Anton Paar), equipped with a diffusion air bearing and connected to a pneumatic supply – an oil-free Jun-Air compressor and air drying block. The device is equipped with a Peltier system for temperature control in the range of –20°C to 200°C and an external thermostatic VISCOTHERM V2 system, working in the temperature range of –20°C to 200°C. The rheometer control and measurement data analysis were performed using Rheoplus software. The tests were carried out using a cone-plate measuring system with a shear rate range of 0.01–100 s-1 at 20°C for lubricating compositions prepared on various oil bases. To evaluate the value of rheological parameters, the results of tests of the dependence between shear stress and shear rate (flow curves) were used. For the theoretical determined on the flow curves, the following rheological models were used: Bingham, Herschel–Bulkley, Casson, and Tscheuschner. The values of the shear stress (yield point) in depending on the type of dispersion phase has changed. This proves that the use of a base oil with the appropriate functional properties does not weaken, but reinforces the spatial structure of a lubricating grease. It has an important meaning when selecting construction parameters when designing a central lubrication system with grease made from a vegetable oil base (Abyssinian oil). The rheological properties of the lubricating grease are influenced by the type of base oil and thickener, any additives in the grease, the production technology of the grease, and the conditions in which it is used. The tests revealed an important influence of the base oil on the rheological parameters that describe the behaviour of lubricating compositions subjected to stresses and strains in a lubricating system.

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Oil Pumping in High Speed and High Loaded Ball Bearings

Volume 4: Turbo Expo 2004 ◽

10.1115/gt2004-53406 ◽

2004 ◽

Cited By ~ 3

Author(s):

Michael Flouros

Keyword(s):

High Speed ◽

Ball Bearing ◽

Research Programme ◽

Aircraft Engine ◽

Ball Bearings ◽

European Research ◽

Rolling Bearings ◽

Engine Design ◽

Oil Flow ◽

Total Oil

Trends in aircraft engine design cause increased mechanical stress requirements for rolling bearings. Consequently high amounts of heat are rejected which results in high oil scavenge temperatures. The direction of oil flow in the bearing can considerably affect the heat transported by the oil. An RB199 turbofan bearing and its associated chamber were modified to carry out the survey. The test bearing was a 124mm PCD ball bearing. The bearing has a split inner-ring employing under-race lubrication by two individual jets. The total oil flow could be devided to any ratio through the jets. This had an impact on the oil scavenge temperatures and the scavenge flows on both sides of the bearing. Significant reduction in the ‘heat to oil’ was achieved when oil was fed at certain proportions (ratio). This work is part of the European Research programme Brite Euram ATOS (Advanced Transmission and Oil Systems).

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