- Email: [email protected]
Grease lubrication studies with plain journal bearings
SYSTEMATIC ABSTRACTS cuum and other controlled atmospheres. The properties which have been studied include elasticity, electrical resistance, and cohesion between whiskers. The atmosphere dependence of these properties suggests that surface adsorption of contaminants is the most important factor in producing changes in graphite friction. There is some evidence that the adsorbed gases reduce surface roughness on an atomic scale. This ability of the adsorbed film to smooth out surface asperities may be used to explain some of the friction and wear characteristics of graphite. The Relation Between Friction and Surface Microtopography. J. D. Huffington. Research, 14 (1961) 193195; 3 figs., I table, 6 refs. The way in which the frictional force (or the real area of contact) between surfaces varies with load depends for elastic deformation on the surface microtopography. A simple theoretical relationship has been obtained which defines surface “roughness” in terms of the real contact area which the surface produces when pressed against another surface. (See also Wear, 3 (1910) 26, 473.) a.3 Skin
Friction
Review of the Effect of Distributed Surface Roughness on Boundary-layer Transition. Albert L. Braslow (NASA). AGARD Refiort
77
254. April 1960. 13 pp. (Presented at AGARD Fluid Dynamics Panel, Boundary Layer Research Meeting, London, April 25-29, 1960.) This paper will deal with the effects on boundary-layer transition of discrete particles of roughness, that is, particles of a three-dimensional nature such as sand grains or rivets or spattered bugs. Two-dimensional roughness, such as spanwise ridges, will be discussed only to compare the transition phenomena with the three-dimensional roughness case. The Normal Impingement Jet on a Flat Surface.
P. Bradshaw
of a Circular
Air
and Edna M. Love.
AevonauR G M 3205,
tiral Resenrch Council (Gv. &it.)
1961. 8 pp. Measurements of velocity magnitude and direction, static pressure, and skin friction have been made in a circular turbulent jet impinging normally on a flat surface. The speed in the jet just before impingement was 135 ft./set and its radius was about 2.5 in. The region of increased static pressure near the stagnation point is roughly hemispherical, with a radius slightly larger than that of the jet. The maximum value of skin friction occurs at a radius approximately equal to that of the jet and is about 0.006 of the jet maximum dynamic pressure at the test Reynolds number. The virtual origin of the resulting radial wall jet is very close to the stagnation point.
3. LUBRICATIONAND LUBRICANTS 3.1 Lubrication Physical Base of Lubrication tion. (in German)
due to Adsorp-
W. Bollman
and H. Tannenberger.
buch des 6. Chronometrie,
Internationalen Munich, 1959,
Berichts-
Kongresses
fiir
pp. 755-766;
indentation test capable of selecting lubricants under loads up to 12 tons is described. This shows that a film formed by heating stainless steel in CClzFz will lubricate at 4oo’C when the steel is deformed by over 5o”/“.
II figs., 3 refs. The bases of a lubrication process are discussed where the lubrication is due to adsorbed layers of vapours. In this case the lubricated parts remain dry. Apart from the description of the apparatus the paper contains the results of a number of friction measurements with different classes of lubricating substances as well as a study on abrasion, It is found that saphire (acidic) is lubricated well by organic bases. A (vapour) lubricant can inhibit the abrasive action of wear debris.
Perturbation Solutions for Gas-Lubricating Films. W. A. Gross and E. C. Zachmanoglou. J.
Lubrication at Vapor-Deposited
Grease Lubrication nal Bearings.
High Temperatures With Surface Coatings. D. J. Baldwin and G. W. Rowe. J. Basic Eng. (I:zME Trans., Ser. D), 83 (2) (1961) 133-
Investigates friction of metals which have been coated with inorganic films by reaction with their surrounding atmosphere. A simple
Basic
Eng.
(1961)
‘39-144.
(ASME
Trans.
Ser.
D),
83
(2)
Perturbation solutions for large and small bearing numbers are developed and applied to steady, self-acting, infinitely long, journal and plane wedge films. Bearing films of this type develop load capacity as a consequence of relative surface motion. The solutions have validity for all ranges of geometrical parameters. Studies With
Plain Jour-
L. J. Bradford, E. M. Barber and J. R. Muenger. J. Basic Eng. (ASME Trans., Ser. D), 83 (2) (1961) 153-161. Grease-lubricated plain bearings will operate with relatively low coefficients of friction and low lubricant consumption as shown by an Wear,
j
(1962) 74-82
experimental investigation on j$-in.-diam bearings. Formation of a “rheodynamic” load-carrying film; cx+dencc of thixotropic behavior; and effects of \wiation of load, feed rate, and lubricant speed, clearance. properties are demonstrated. Hydrodynamic Lubrication of a Roller Bearing - Introduction of Parameters to Obtain Charts for Calculation. F. V’. v. Hackewitz. J. Appl. Mwh. (ASME Tmzs., SW. E), z8 (2) (1961) ~97-299. Relative and dimensionless magnitudes are introduced. They help to establish charts which represent Isothermal results for different bearing design and various running conditions.
Silicones in Lubrication. I>. R. Johnson and M. R. Porter. Brzt. Powev Eng., 3 (I) (1961) 46-50. Some unusual physical properties are pro-
4.
%hCHINE
4.1 Bearings Adiabatic Analysis of Elastic, Centrally Pivoted, Sector, Thrust-Bearing Pads. B. Sternlicht, G. I<. Carter and E. H. rlrwas. j. il~pl. MecA. (ASME Trans. SPY. E) I 28 (2) (1961) 179-187. Emphasizes the importance of temperature in thrust-bearing analysis. The analysis presented consists of simultaneous solution of the momentum, energy, and elasticity equations for centrally pivoted, sector-shaped, thrustb caring pads. Performance of Elastic, Centrally Pivoted, Sector, Thrust-Bearing Pads. I. B. Sternlicht, J. C. Reid, Jr. and E. B. Xrwas. ,r. Basic Eng. (ASME Trans., Ser. D) 83 (2) (1961) 169~178. Describes a method of analysis that was worked out for these bearings, which includes viscosity variations in the fluid film and an approximate calculation of the pad deflections caused by the hydrodynamic pressures. Equilibrium of moments is satisfied, laminar and adiabatic conditions are assumed, and the lubricant is incompressible. The Effect of the Method of Compensation on Hydrostatic Bearing Stiffness. Stanley B. Malanoski and Alfred iN. Loeb. J. Basic (1961)
Eng. (ASME 179-187.
Trans.,
SFY. D),
83 (2)
Capillary, orifice, and flow control valve compensation of hydrostatic thrust bearings
duced, due to the molecular structure 111 silicones, making them particularI>- valuably as high-tcmpcrature lubricants. Evaluation of Drawing Lubricants for Tantalum and Uranium. I<. I. Batista, G. S. IHanks, J. RI. Taub and U. J. Murphy. J.wbvi~&i~x Engineering, 17 (0) (1961) 414-418; 5 figs., 1 tables, I ref. A simplified testing dcxricc utilizing a draw bench and readily available auxiliary components has been de\,cloped for evaluating the friction-rcducingcharactcristicsofpossiblc lubricants for USCwith usual metals and alloys for which such information has not yet been developed. Data ha1.c been obtained for a variety of lubricants and die materials CIW plo)-cd with tantalum and uranium, t\vvosuch metals for which additional forming information has been needed. The device and procedure prox+des a means for extensive cvalustion of other combinations of dies, lubricants. and metals.
I’ARTS
are investigated theoretically with regard to the effect of these three methods of compensation on the stiffness of the lubricant film. Equations are derived which permit rapid determination of bearing stiffness at any given load and film thickness. Inertia Effects ings. D. Dowson. J. Ser. D),
in Hydrostatic Basic
83 (2) (1961)
Eng.
Thrust
(ASME
BearTrans.,
227-234.
Includes the predominant inertia terms in an analysis of hydrostatic thrust bearings. The influence of centripetal accelerations on the distribution of pressure is found to be considerable. For parallel surface bearings of constant film thickness the inertia effects are found to be detrimental to load capacity. In a stepped bearing, however, correct location of the step can result in an increased load capacity at speed. A consequence of the inclusion of inertia terms in the analysis is the existence of a velocity component in the axial direction. An Assessment of the Value of Theory in Predicting Gas-Bearing Performance. S. Cooper. J. Baszc Eng. (ASME Trans., SW. D),
83 (2) (1961)
195-200.
The object of the paper is to indicate the value of theoretical investigations of hydrodynamic finite bearings under steady-state conditions. Methods of solution of Reynold’s equation by both desk and digital computing, and methods of stabilizing the processes of solution, are described. The nondimensional
Friction
Review of the Effect of Distributed Surface Roughness on Boundary-layer Transition. Albert L. Braslow (NASA). AGARD Refiort
77
254. April 1960. 13 pp. (Presented at AGARD Fluid Dynamics Panel, Boundary Layer Research Meeting, London, April 25-29, 1960.) This paper will deal with the effects on boundary-layer transition of discrete particles of roughness, that is, particles of a three-dimensional nature such as sand grains or rivets or spattered bugs. Two-dimensional roughness, such as spanwise ridges, will be discussed only to compare the transition phenomena with the three-dimensional roughness case. The Normal Impingement Jet on a Flat Surface.
P. Bradshaw
of a Circular
Air
and Edna M. Love.
AevonauR G M 3205,
tiral Resenrch Council (Gv. &it.)
1961. 8 pp. Measurements of velocity magnitude and direction, static pressure, and skin friction have been made in a circular turbulent jet impinging normally on a flat surface. The speed in the jet just before impingement was 135 ft./set and its radius was about 2.5 in. The region of increased static pressure near the stagnation point is roughly hemispherical, with a radius slightly larger than that of the jet. The maximum value of skin friction occurs at a radius approximately equal to that of the jet and is about 0.006 of the jet maximum dynamic pressure at the test Reynolds number. The virtual origin of the resulting radial wall jet is very close to the stagnation point.
3. LUBRICATIONAND LUBRICANTS 3.1 Lubrication Physical Base of Lubrication tion. (in German)
due to Adsorp-
W. Bollman
and H. Tannenberger.
buch des 6. Chronometrie,
Internationalen Munich, 1959,
Berichts-
Kongresses
fiir
pp. 755-766;
indentation test capable of selecting lubricants under loads up to 12 tons is described. This shows that a film formed by heating stainless steel in CClzFz will lubricate at 4oo’C when the steel is deformed by over 5o”/“.
II figs., 3 refs. The bases of a lubrication process are discussed where the lubrication is due to adsorbed layers of vapours. In this case the lubricated parts remain dry. Apart from the description of the apparatus the paper contains the results of a number of friction measurements with different classes of lubricating substances as well as a study on abrasion, It is found that saphire (acidic) is lubricated well by organic bases. A (vapour) lubricant can inhibit the abrasive action of wear debris.
Perturbation Solutions for Gas-Lubricating Films. W. A. Gross and E. C. Zachmanoglou. J.
Lubrication at Vapor-Deposited
Grease Lubrication nal Bearings.
High Temperatures With Surface Coatings. D. J. Baldwin and G. W. Rowe. J. Basic Eng. (I:zME Trans., Ser. D), 83 (2) (1961) 133-
Investigates friction of metals which have been coated with inorganic films by reaction with their surrounding atmosphere. A simple
Basic
Eng.
(1961)
‘39-144.
(ASME
Trans.
Ser.
D),
83
(2)
Perturbation solutions for large and small bearing numbers are developed and applied to steady, self-acting, infinitely long, journal and plane wedge films. Bearing films of this type develop load capacity as a consequence of relative surface motion. The solutions have validity for all ranges of geometrical parameters. Studies With
Plain Jour-
L. J. Bradford, E. M. Barber and J. R. Muenger. J. Basic Eng. (ASME Trans., Ser. D), 83 (2) (1961) 153-161. Grease-lubricated plain bearings will operate with relatively low coefficients of friction and low lubricant consumption as shown by an Wear,
j
(1962) 74-82
experimental investigation on j$-in.-diam bearings. Formation of a “rheodynamic” load-carrying film; cx+dencc of thixotropic behavior; and effects of \wiation of load, feed rate, and lubricant speed, clearance. properties are demonstrated. Hydrodynamic Lubrication of a Roller Bearing - Introduction of Parameters to Obtain Charts for Calculation. F. V’. v. Hackewitz. J. Appl. Mwh. (ASME Tmzs., SW. E), z8 (2) (1961) ~97-299. Relative and dimensionless magnitudes are introduced. They help to establish charts which represent Isothermal results for different bearing design and various running conditions.
Silicones in Lubrication. I>. R. Johnson and M. R. Porter. Brzt. Powev Eng., 3 (I) (1961) 46-50. Some unusual physical properties are pro-
4.
%hCHINE
4.1 Bearings Adiabatic Analysis of Elastic, Centrally Pivoted, Sector, Thrust-Bearing Pads. B. Sternlicht, G. I<. Carter and E. H. rlrwas. j. il~pl. MecA. (ASME Trans. SPY. E) I 28 (2) (1961) 179-187. Emphasizes the importance of temperature in thrust-bearing analysis. The analysis presented consists of simultaneous solution of the momentum, energy, and elasticity equations for centrally pivoted, sector-shaped, thrustb caring pads. Performance of Elastic, Centrally Pivoted, Sector, Thrust-Bearing Pads. I. B. Sternlicht, J. C. Reid, Jr. and E. B. Xrwas. ,r. Basic Eng. (ASME Trans., Ser. D) 83 (2) (1961) 169~178. Describes a method of analysis that was worked out for these bearings, which includes viscosity variations in the fluid film and an approximate calculation of the pad deflections caused by the hydrodynamic pressures. Equilibrium of moments is satisfied, laminar and adiabatic conditions are assumed, and the lubricant is incompressible. The Effect of the Method of Compensation on Hydrostatic Bearing Stiffness. Stanley B. Malanoski and Alfred iN. Loeb. J. Basic (1961)
Eng. (ASME 179-187.
Trans.,
SFY. D),
83 (2)
Capillary, orifice, and flow control valve compensation of hydrostatic thrust bearings
duced, due to the molecular structure 111 silicones, making them particularI>- valuably as high-tcmpcrature lubricants. Evaluation of Drawing Lubricants for Tantalum and Uranium. I<. I. Batista, G. S. IHanks, J. RI. Taub and U. J. Murphy. J.wbvi~&i~x Engineering, 17 (0) (1961) 414-418; 5 figs., 1 tables, I ref. A simplified testing dcxricc utilizing a draw bench and readily available auxiliary components has been de\,cloped for evaluating the friction-rcducingcharactcristicsofpossiblc lubricants for USCwith usual metals and alloys for which such information has not yet been developed. Data ha1.c been obtained for a variety of lubricants and die materials CIW plo)-cd with tantalum and uranium, t\vvosuch metals for which additional forming information has been needed. The device and procedure prox+des a means for extensive cvalustion of other combinations of dies, lubricants. and metals.
I’ARTS
are investigated theoretically with regard to the effect of these three methods of compensation on the stiffness of the lubricant film. Equations are derived which permit rapid determination of bearing stiffness at any given load and film thickness. Inertia Effects ings. D. Dowson. J. Ser. D),
in Hydrostatic Basic
83 (2) (1961)
Eng.
Thrust
(ASME
BearTrans.,
227-234.
Includes the predominant inertia terms in an analysis of hydrostatic thrust bearings. The influence of centripetal accelerations on the distribution of pressure is found to be considerable. For parallel surface bearings of constant film thickness the inertia effects are found to be detrimental to load capacity. In a stepped bearing, however, correct location of the step can result in an increased load capacity at speed. A consequence of the inclusion of inertia terms in the analysis is the existence of a velocity component in the axial direction. An Assessment of the Value of Theory in Predicting Gas-Bearing Performance. S. Cooper. J. Baszc Eng. (ASME Trans., SW. D),
83 (2) (1961)
195-200.
The object of the paper is to indicate the value of theoretical investigations of hydrodynamic finite bearings under steady-state conditions. Methods of solution of Reynold’s equation by both desk and digital computing, and methods of stabilizing the processes of solution, are described. The nondimensional