On the Significance of the Inlet Pressure Build-Up in the Design of Tilting-Pad Bearings

1990 ◽  
Vol 112 (1) ◽  
pp. 17-22 ◽  
Author(s):  
Cz. M. Rodkiewicz ◽  
K. W. Kim ◽  
J. S. Kennedy
Keyword(s):  
Thrust Bearing ◽  
Ambient Pressure ◽  
Inlet Pressure ◽  
Load Carrying Capacity ◽  
Integral Theorem ◽  
Lubricating Film ◽  
Tilting Pad ◽  
Load Carrying ◽  
Momentum Integral ◽  
Entrance Pressure

An operating tilting-pad thrust bearing generates a fore-region which is responsible for maintaining, at the bearing entrance, a pressure which is higher than the ambient pressure. This entrance pressure, in the presented analysis, is obtained by applying to the fore-region the momentum integral theorem. The solution of the lubricating film region is then obtained by using this modified inlet pressure. This solution yields the pressure distribution, the load carrying capacity, the film ratio and the frictional force for several values of the modified Reynolds number and various pivot positions. The analysis shows that there is a significant influence of the fore-region pressure on the bearing performance and that to properly design efficient tilting-pad bearing this effect should be taken into consideration.

Fluid Film Lubrication of Parallel Thrust Surfaces

1946 ◽  
Vol 155 (1) ◽  
pp. 49-67 ◽  
Author(s):  
A. Fogg
Keyword(s):  
Thrust Bearing ◽  
Fluid Film ◽  
Load Carrying Capacity ◽  
Low Friction ◽  
Metallic Contact ◽  
Tilting Pad ◽  
Load Carrying ◽  
Parallel Surfaces ◽  
Film Lubrication ◽  
Fluid Film Lubrication

During the course of an investigation into the general characteristics of various types of thrust bearing, it has been shown that opposed parallel surfaces, under certain conditions of operation, have a load carrying capacity approaching that of tilting pad bearings of the Michell type and of the same bearing area. Considerable evidence has been obtained, such as the low friction losses, the dependence of coefficient of friction on viscosity, speed and load, and the apparent absence of metallic contact, which strongly indicates that these bearings operate under fluid film conditions. Their performance does not seem to depend on a rounded inlet edge, and the apparent establishment of fluid film conditions without the usually accepted requirement of convergence of the bearing surfaces is regarded as a new phenomenon in lubrication. A tentative theory on broad lines is suggested as an explanation of the behaviour.

Paper 16: Tilting Pad Thrust Bearings: Rapid Design Aids

1969 ◽  
Vol 184 (12) ◽  
pp. 120-138 ◽  
Author(s):  
F. A. Martin
Keyword(s):  
Carrying Capacity ◽  
Thrust Bearing ◽  
Total Power ◽  
Load Carrying Capacity ◽  
Specific Load ◽  
Thrust Bearings ◽  
Size Number ◽  
Tilting Pad ◽  
Load Carrying ◽  
Chart Design

Two slide chart design aids are developed for tilting pad thrust bearings in order ( a) to give guidance on load-carrying capacity, considering such limits as allowable oil film thickness and maximum pad temperature, and ( b) to enable the designer to estimate directly the total power loss in double thrust bearing assemblies. These slide charts (each consisting of two sheets) enable variables such as pad size, number of pads, oil specification, specific load, and collar speed to be considered individually. Thus the designer has a tool from which he can obtain a ‘feel’ for bearing performance and see at a glance the interplay between all the variables.

scholarly journals EXPERIMENTAL STUDIES OF PRESSURE DISTRIBUTION IN TILTING PAD THRUST BEARING WITH SINGLE CONTINUOUS SURFACE PROFILED SECTOR SHAPED PADS

2012 ◽  
pp. 129-133
Author(s):  
ABHIJEET PATIL ◽  
P.B. SHINDE ◽  
S.P. CHAVAN
Keyword(s):  
Carrying Capacity ◽  
Thrust Bearing ◽  
Experimental Studies ◽  
Load Carrying Capacity ◽  
Slider Bearing ◽  
Design Data ◽  
Hydrodynamic Bearing ◽  
Tilting Pad ◽  
Load Carrying ◽  
Continuous Surface

The effect of the film shape on the load carrying capacity of a hydrodynamically lubricated bearing has not been considered an important factor in the past. Flat faced tapered bearing and the Raileigh's step bearing of constant film thickness have been the primary forms of film shapes for slider bearing studies and design data developments. There are indications in the literature that surface profiling/texturing can have significant and positive influence on the load carrying capacity of hydrodynamic pad thrust bearings. Therefore, the objective of this paper is to compare the experimental results of pressure temperature distributions in slider bearing with flat surface and with different single continuous surface profiled (Cycloidal,Catenoidal,Quadratic) sector shaped pads. Pressure results presented in this paper can provide a platform for validation of theoretical models. An experimental study has been performed to investigate the influence of single continuous surface profiled sector shaped pads in tilting pad thrust bearing. It has been found that with cycloidal shaped surface profiled sector shaped pads the pressure generated within fluid film is enhanced which in turn causes enhancement in load bearing capacity of hydrodynamic bearing.

scholarly journals Numerical analysis and experimental research on load carrying capacity of water-lubricated tilting-pad thrust bearings

2018 ◽  
Vol 19 (2) ◽  
pp. 201 ◽  
Author(s):  
Xiuli Zhang ◽  
Gengyuan Gao ◽  
Zhongwei Yin ◽  
Yanzhen Wang ◽  
Chao Gao
Keyword(s):  
Film Thickness ◽  
Thrust Bearing ◽  
Hydrodynamic Lubrication ◽  
Optimization Method ◽  
Load Carrying Capacity ◽  
Thrust Bearings ◽  
Lubrication Regime ◽  
Tilting Pad ◽  
Load Carrying ◽  
Minimum Film Thickness

Water-lubricated bearings are expected to be widely used because of convenience, green, safe and energy saving. The purpose of this study is to investigate the load carrying property of water-lubricated tilting-pad thrust bearings. A large amount of numerical analyses are undertaken based on computational fluid dynamics and the optimization method of pivot location and the calculation method of minimum film thickness are summarized. A thrust bearing is designed according to the numerical results and is tested by experiments. The experimental results validate the numerical method and the minimum film thickness to surface roughness ratio corresponding to the change of bearing lubrication regime from mixed lubrication to hydrodynamic lubrication is obtained.

Design and fabrication of the tilting-pad thrust bearing surface profile

2018 ◽  
Vol 70 (8) ◽  
pp. 1402-1407
Author(s):  
Zhanchao Wang ◽  
Fei Guo ◽  
Ying Liu ◽  
Xiangfeng Liu ◽  
Yuming Wang
Keyword(s):  
Thrust Bearing ◽  
Design Method ◽  
Surface Profile ◽  
Load Carrying Capacity ◽  
Laser Method ◽  
Content Type ◽  
Tilting Pad ◽  
Load Carrying ◽  
Bearing Load ◽  
Thrust Pad

PurposeThis paper aims to design a new surface profile with simpler processing technology, which makes the bearing load carrying capacity (LCC) close to that of conventional tilting-pad thrust bearing.Design/methodology/approachThe paper analyzes the LCC of the thrust pad with crown profile and designs a new profile, whose performance is similar to the crown profile. The laser method is introduced to fabricate the new profile. The profile with tiny crown height can be fabricated by the laser with the proper parameters.FindingsIt was found that there is an optimum value, which is best in terms of the capacity of tilting-pad thrust bearing reach. The new profile with proper parameters can replace the crown profile.Originality/valueThe new profile can replace the crown profile and is easier to be made. The new design method could be adopted for designing the pad surface profile of the tilting-pad thrust bearing.

Density Variation Effects in Stepped-Thrust Bearings

1959 ◽  
Vol 26 (3) ◽  
pp. 337-340
Author(s):  
C. F. Kettleborough
Keyword(s):  
Coefficient Of Friction ◽  
Carrying Capacity ◽  
Thrust Bearing ◽  
Density Variation ◽  
Load Carrying Capacity ◽  
Thrust Bearings ◽  
Load Carrying ◽  
The Coefficient Of Friction

Abstract The problem of the stepped-thrust bearing is considered but, whereas normally volumetric continuity is assumed, the equations are solved assuming mass continuity; i.e., the variation of density is also considered as well as the effect of the stepped discontinuity on the load-carrying capacity and the coefficient of friction. Computed theoretical curves illustrate the importance of the density on the operation of this bearing and, in part, explain results already published.

Deformation Effects on the Load Carrying Capacity of the Barrel Bearing in Axial Piston Pumps and Motors

2006 ◽  
Author(s):  
Peter A. J. Achten ◽  
Marc P. A. Schellekens
Keyword(s):  
Elastic Deformation ◽  
Carrying Capacity ◽  
Thrust Bearing ◽  
Pressure Profile ◽  
Load Carrying Capacity ◽  
Axial Piston Pumps ◽  
Load Carrying ◽  
Face Seals ◽  
Axial Piston Machine ◽  
Axial Piston

Most hydrostatic pumps and motors apply mechanical face seals, often also acting as a thrust bearing. The load carrying capacity of these bearings is very much dependent on the pressure profile generated in the sealing gap. Previous research, outside pumps and motors, has already shown that the gap pressure profile is largely influenced by small radial deformations of the seal lands. This paper discusses the elastic deformation of pump components and the effects of these deformations on the load carrying capacity of a barrel in an axial piston machine.

On the Influence of Finite Wall Conductance and Inertia Effects of Hydrostatic Thrust Bearing

1978 ◽  
Vol 100 (2) ◽  
pp. 271-278
Author(s):  
V. K. Kapur ◽  
Kamlesh Verma
Keyword(s):  
Analytical Study ◽  
Thrust Bearing ◽  
Necessary Conditions ◽  
Axial Magnetic Field ◽  
Constant Angular Velocity ◽  
Frictional Torque ◽  
Load Carrying Capacity ◽  
Inertia Effects ◽  
Parallel Disks ◽  
Load Carrying

An analytical study is presented on the influence of finite wall conductance and inertia effects in magnetohydrodynamic lubrication flow between two parallel disks, one of which is rotating with constant angular velocity, in the presence of the axial magnetic field. Numerical results showing the behavior of wall conductance and inertia effects on pressure distribution, load carrying capacity, critical speed, and frictional torque of the bearing are obtained. Results obtained will provide necessary conditions for wall materials to improve the bearing performance.

The Performance of Hydrodynamic Lubricating Films With Viscosity Variations Perpendicular to the Direction of Motion

1972 ◽  
Vol 94 (1) ◽  
pp. 44-48 ◽  
Author(s):  
E. B. Qvale ◽  
F. R. Wiltshire
Keyword(s):  
Film Thickness ◽  
Carrying Capacity ◽  
Load Carrying Capacity ◽  
End Effects ◽  
Parametric Curves ◽  
One Dimensional ◽  
Lubricating Film ◽  
Families Of Curves ◽  
Load Carrying ◽  
The Coefficient Of Friction

The effects of prescribed viscosity variations across a hydrodynamic lubricating film are studied. The film is strictly one dimensional and end effects are neglected. The viscosity variations are given by three families of curves. The considerable decreases (in the limit 100 percent) and occasional increases in the coefficient of friction that can occur for constant film thickness and load-carrying capacity are evaluated and the results are presented in terms of parametric curves. Important physical situations where these viscosity variations may be observed or produced are described.

The Effect of Centrifugal Stretching in High-Speed, Self-Acting Gas Bearings Operating under Steady-State Conditions

1974 ◽  
Vol 16 (3) ◽  
pp. 139-146
Author(s):  
K. S. H. Sadek ◽  
B. N. Cole ◽  
D. Dowson
Keyword(s):  
Radial Growth ◽  
High Speed ◽  
Load Carrying Capacity ◽  
Gas Bearings ◽  
Rotary Machine ◽  
Lubricating Film ◽  
Pressure Distributions ◽  
High Speeds ◽  
Load Carrying ◽  
Very High

The study reported in this paper arose from an investigation of methods of achieving oil-free compression of refrigerant vapours. One part of the investigation included a feasibility study of a high-speed rotary machine running in self-acting gas bearings lubricated by the refrigerant. In certain designs of very high-speed rotor-bearing arrangements, centrifugal or radial growth of the journal might disturb the shape and magnitude of the nominal clearance space and thus affect the performance characteristics of the bearing. The nature and magnitude of these changes in bearing performance for uniform and for two forms of non-uniform centrifugal growth have been examined theoretically. Typical gas-film pressure distributions are presented together with design charts showing how attitude angle and load carrying capacity vary with speed. Comparisons are made with the performance of bearings having the same eccentricity ratio on the mid-plane, and guidance is given on the calculation of uniform radial growth at high speeds. It is concluded that changes in lubricating film geometry resulting from centrigual stretching might have a significant effect upon the performance of certain high-speed, self-acting gas-lubricated bearings.

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