Calculation of Oil Film Thickness on Bearing Raceway Grooves by Measuring Raceway Outer Ring Temperature

2021 ◽  
Author(s):  
Kenji Matsumoto ◽  
Hideharu Koga ◽  
Yuki Ono ◽  
Yuji Mihara
Keyword(s):  
Film Thickness ◽  
Outer Ring ◽  
Oil Film ◽  
Bearing Raceway

The Surface-Roughness of Bearing-Surfaces and its Relation to Oil Film Thickness at Breakdown

1949 ◽  
Vol 161 (1) ◽  
pp. 73-79 ◽  
Author(s):  
A. Cameron
Keyword(s):  
Surface Roughness ◽  
Film Thickness ◽  
Hydrodynamic Theory ◽  
Quantitative Relation ◽  
Metal Contact ◽  
Initial Contact ◽  
Frictional Drag ◽  
Average Roughness ◽  
Finished Steel ◽  
Oil Film

In this paper the relation of surface roughness of bearing surfaces to allowable film thickness is studied quantitatively with a simple Michell pad apparatus. The pads used were faced with white metal and ran against mild steel collars. The lubricants studied were water, soap solution, paraffin, and light oil. There was little difference in the frictional behaviour of any of the lubricants, except that the aqueous lubricants would not run with very finely finished steel surfaces. The onset of metal to metal contact was detected by an increase in the frictional drag, and also by the change in electrical conductivity between the pad and collar—an extremely sensitive method. The paper shows that there is, at any rate for this system, a quantitative relation between the total surface roughness of the rubbing surfaces and the calculated oil film thickness both at the initial metal to metal contact and seizure. Initial contact occurs when the outlet film thickness, calculated from normal hydrodynamic theory, falls to three times the maximum surface roughness and seizure occurs when it is double the average roughness.

Influence of Surface Waviness on the Thermal Elastohydrodynamic Lubrication of an Eccentric-Tappet Pair

2013 ◽  
Vol 135 (2) ◽  
Author(s):  
J. Wang ◽  
C. H. Venner ◽  
A. A. Lubrecht
Keyword(s):  
Film Thickness ◽  
Elastohydrodynamic Lubrication ◽  
Surface Waviness ◽  
Film Pressure ◽  
Oil Film ◽  
Working Cycle ◽  
Temperature Oscillations ◽  
Minimum Film Thickness ◽  
Traction Coefficient ◽  
Oil Film Pressure

The effect of single-sided and double-sided harmonic surface waviness on the film thickness, pressure, and temperature oscillations in an elastohydrodynamically lubricated eccentric-tappet pair has been investigated in relation to the eccentricity and the waviness wavelength. The results show that, during one working cycle, the waviness causes significant fluctuations of the oil film, pressure, and temperature, as well as a reduction in minimum film thickness. Smaller wavelength causes more dramatic variations in oil film. The fluctuations of the pressure, film thickness, temperature, and traction coefficient caused by double-sided waviness are nearly the same compared with the single-sided waviness, but the variations are less intense.

scholarly journals Artificial Neural Network Model for Monitoring Oil Film Regime in Spur Gear Based on Acoustic Emission Data

2015 ◽  
Vol 2015 ◽  
pp. 1-12 ◽  
Author(s):  
Yasir Hassan Ali ◽  
Roslan Abd Rahman ◽  
Raja Ishak Raja Hamzah
Keyword(s):  
Neural Network ◽  
Artificial Neural Network ◽  
Film Thickness ◽  
Spur Gear ◽  
Back Propagation Algorithm ◽  
Elman Neural Network ◽  
Feed Forward ◽  
Oil Film ◽  
Feed Forward Network ◽  
Artificial Neural

The thickness of an oil film lubricant can contribute to less gear tooth wear and surface failure. The purpose of this research is to use artificial neural network (ANN) computational modelling to correlate spur gear data from acoustic emissions, lubricant temperature, and specific film thickness (λ). The approach is using an algorithm to monitor the oil film thickness and to detect which lubrication regime the gearbox is running either hydrodynamic, elastohydrodynamic, or boundary. This monitoring can aid identification of fault development. Feed-forward and recurrent Elman neural network algorithms were used to develop ANN models, which are subjected to training, testing, and validation process. The Levenberg-Marquardt back-propagation algorithm was applied to reduce errors. Log-sigmoid and Purelin were identified as suitable transfer functions for hidden and output nodes. The methods used in this paper shows accurate predictions from ANN and the feed-forward network performance is superior to the Elman neural network.

scholarly journals Analysis of misaligned journal bearing lubrication performance considering the effect of lubricant couple stress and shear thinning

2021 ◽  
Vol 37 ◽  
pp. 282-290
Author(s):  
Junchao Zhu ◽  
Haiyu Qian ◽  
Huabing Wen ◽  
Liangyan Zheng ◽  
Hanhua Zhu
Keyword(s):  
Film Thickness ◽  
Couple Stress ◽  
Journal Bearing ◽  
Shear Thinning ◽  
Inlet Temperature ◽  
Stress Effect ◽  
Misalignment Angle ◽  
Oil Film ◽  
Stress Coefficient ◽  
Lubrication Performance

ABSTRACT This paper investigates journal bearings, and builds a lubrication model taking into account misalignment, the lubricant couple stress effect and shear thinning. In order to explore the sensitivity of couple stress fluid lubrication performance to oil film thickness, we introduce the critical oil film thickness coefficient. The results show that the sensitivity increases with the increase of the couple stress coefficient, and it is highest in the area of minimum oil film thickness. Compared with a parallel journal, increases in the misalignment angle strengthen the effect of couple stress. Shear thinning also plays an important role in bearing lubrication performance. For a low oil inlet temperature, the effect of shear thinning increases with the increase of the couple stress parameter. For a high oil inlet temperature, the influence is negligible. An increase in the misalignment angle will not further enhance the effect of shear thinning.

Studying Systems of Stabilization of Supports in Hydrostatic Machine Tool

2012 ◽  
Vol 622-623 ◽  
pp. 489-493
Author(s):  
Iskander Beisembetov ◽  
Sabyi Ussupov ◽  
Bakhyt Absadykov ◽  
Beken Arymbekov ◽  
Birzhan Bektibay
Keyword(s):  
Film Thickness ◽  
Machine Tools ◽  
Operating Conditions ◽  
Coefficient Of Performance ◽  
Operational Parameters ◽  
Automatic Stabilization ◽  
Design Elements ◽  
Oil Film ◽  
Hydrostatic Bearing ◽  
Automatic Control Systems

Development relevance to improve the operational parameters of the support units of machine tools in their design elements is introduced that increase the rigidity of the components, their carrying capacity, damp occurring vibrations in the process, the coefficient of performance (COP), smoothness of motion, positioning accuracy, reducing the wear of their working surfaces and maintain the original accuracy. A number of engineering development [1], [2], aimed at improving the above characteristics of the machine by changing and improving design of reference nodes used in these rails rolling bearings, aerostatic and hydrostatic guides, as well as the use of automatic control systems of its basic parameters, determine its quality. However, in some operating conditions in which errors occur, mainly due to the instability of oil-film thickness (gap) between the mobile and immobile elements of the hydrostatic bearing. For high accuracy requirements it will negatively affect the quality of machined parts and equipment performance. On this basis, it becomes apparent urgency of the problem of automatic stabilization of oil-film thickness (gap) in the IR. To ensure high precision equipment to improve power system hydrostatic bearing units of machine tools. This, in turn, creates the prerequisite for the development of stabilization systems of the gap in the hydrostatic bearing, with the help of which the thickness of oil layer in them would be kept constant even with significant dynamic load on the support.

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