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Self-lubricating composites of porous nickel and nickel-chromium alloy impregnated with barium fluoride-calcium fluoride eutectic
248
LITERATURE
naphthenic base oil provided an improvement in the life performance equivalent to that obtained with the paraffinic base lubricant. Extreme Values of the Pressure Coefficient of Viscosity. E. Kuss, Angew. Clzem., Intern. Edition in English, 4 (II) (rg6.j) 944-950; 7 figs., I table, 14 refs. The pressure coefficients of viscosity of hydrocarbons and ethers containing 2-4 phenyl groups linked either directly, viu methylene bridges, or via CH(CHa) bridges, were studied with a view to elucidating the reason for the extreme viscosity-pressure behavior of certain mineral oils. Measurements were made in the range of i-2ooo atm at 25, 40, 60, and 80°C. The results show the existence of a simple relationship between molecular structure and viscosity-pressure coefficient, and suggest applications in control engineering and lubrication technology. (See also the abstract of “Extremes of Viscosity-Pressure Dependence”, Wecsv, o (1966) 242.) Self-lubricating Composites of Porous Nickel and Nickel-Chromium Alloy Impregnated with Barium Fluoride-Calcium Fluoride Eutectic. H. E. Sliney, U.S. ;Vatl. Aerma, Spuce B d&n., Tech. iVote. NASA TLV-G3484, 1966, rg pp. MOSS Lubrication of Various Metals. H. F. Barry and J. P. Binkelman, Lubricatiort Eng., zz (4) (1966) x39-145; 9 figs., 3 tables, r4 refs. Coefficients of friction were measured for unbonded films of MO&, when used as a dry lubricant for bearing surfaces made from a variety of metals. In al1 cases, the mating surfaces were of the same composition. The data indicate that the friction coefficient is dependent upon the air humidity and the metal substrate. In dry air, there appears to be essentially no change in the MOSS friction coefficient due to changing load or speed in the limited range studied. Thus, the MO& films appear to obey Amontons’ law. Also, in dry air there appears to be essentially no relationship between metal hardness and the observed friction. In moist air, the apparent decline in the MO& friction coefficient with increasing speed and/or load is believed to be due to frictional heating which causes a reduction in surface humidity. In boundary lubrication tests, MO& added to a mineral oil prevented scoring or reduced frictionon most metals tested, except titanium and lead. Evaluation of Solid-lubricant Dispersions. A. J. Stock, Lubricalion Elag., za (4) (x966) 140--x52; IO figs., I table, 14 refs. Wear,
IO (1967) q--259
4. MACHINE
z4NI) CURREST
EVEN’W
PARTS
4.r. Uails The Unity of Engineering as Illustrated by Transport Technology. F. ‘l. Barwell, Inaugural lecture, University College of Su-ansea, Gt. Britain; II figs.. 2 tables, IL refs. Roaring Rails. (in English) B. M. Belgaumkar, J. Sci. Eng. Res. Imdia, 8 (Pt. 2) (1964) 249-256. For abstract see AppL. Mech. Rev., 19 (9) (19Gfd 774. 4.2.
Bearings
Determination of Performance Characteristics of Hydrostatic Bearing Systems that Support a Rigid Body. W. Shapiro, V. Castehi and S. Heller, ASLE Trans., 9 (1966) 2722282. An analysis of a system of hydrostatic bearings used to support a rigid structure subjected to either specified loads or movements is described, and results of sample problems are shown. The governing equations are developed, considering generalized system supply circuitry and arbitrary selection of fixed type compensating elements for each bearing. The equations have been programmed for solution on a high-speed digital computer. The methods of solution and conceptual flow chart of the program are described. From specified loads (or alternatively displacements) of a point on the body chosen as the origin, individual bearing performance parameters, resultant body displacements (or alternatively loads), and the hydraulic system parameters are determined. An Adiabatic Solution for the Finite Slider Bearing (L/B = 1) A. A. Raimondi, ASLE Trans., 9 (1~66) 283-298.
The classical case in lubrication of two flat rectangular surfaces has been solved to account for the variable properties of the lubricant. The effect of varying viscosity and density with temperature has been taken into account by solving simultaneously the Reynolds Equation and the Energy Equation for a square pad (LIB = r) with a digital computer. The case of two insulated plates is used; no heat conduction is allowed. The solutions are compared with the classical theory which assumes the lubricant to have constant properties. Curves showing the pressure and temperature distributions are presented. Design curves are given for the performance of fixed pad bearings, pivoted pad bearings with central pivots as well as optimum pivots, and parallel surfaces. A
LITERATURE
naphthenic base oil provided an improvement in the life performance equivalent to that obtained with the paraffinic base lubricant. Extreme Values of the Pressure Coefficient of Viscosity. E. Kuss, Angew. Clzem., Intern. Edition in English, 4 (II) (rg6.j) 944-950; 7 figs., I table, 14 refs. The pressure coefficients of viscosity of hydrocarbons and ethers containing 2-4 phenyl groups linked either directly, viu methylene bridges, or via CH(CHa) bridges, were studied with a view to elucidating the reason for the extreme viscosity-pressure behavior of certain mineral oils. Measurements were made in the range of i-2ooo atm at 25, 40, 60, and 80°C. The results show the existence of a simple relationship between molecular structure and viscosity-pressure coefficient, and suggest applications in control engineering and lubrication technology. (See also the abstract of “Extremes of Viscosity-Pressure Dependence”, Wecsv, o (1966) 242.) Self-lubricating Composites of Porous Nickel and Nickel-Chromium Alloy Impregnated with Barium Fluoride-Calcium Fluoride Eutectic. H. E. Sliney, U.S. ;Vatl. Aerma, Spuce B d&n., Tech. iVote. NASA TLV-G3484, 1966, rg pp. MOSS Lubrication of Various Metals. H. F. Barry and J. P. Binkelman, Lubricatiort Eng., zz (4) (1966) x39-145; 9 figs., 3 tables, r4 refs. Coefficients of friction were measured for unbonded films of MO&, when used as a dry lubricant for bearing surfaces made from a variety of metals. In al1 cases, the mating surfaces were of the same composition. The data indicate that the friction coefficient is dependent upon the air humidity and the metal substrate. In dry air, there appears to be essentially no change in the MOSS friction coefficient due to changing load or speed in the limited range studied. Thus, the MO& films appear to obey Amontons’ law. Also, in dry air there appears to be essentially no relationship between metal hardness and the observed friction. In moist air, the apparent decline in the MO& friction coefficient with increasing speed and/or load is believed to be due to frictional heating which causes a reduction in surface humidity. In boundary lubrication tests, MO& added to a mineral oil prevented scoring or reduced frictionon most metals tested, except titanium and lead. Evaluation of Solid-lubricant Dispersions. A. J. Stock, Lubricalion Elag., za (4) (x966) 140--x52; IO figs., I table, 14 refs. Wear,
IO (1967) q--259
4. MACHINE
z4NI) CURREST
EVEN’W
PARTS
4.r. Uails The Unity of Engineering as Illustrated by Transport Technology. F. ‘l. Barwell, Inaugural lecture, University College of Su-ansea, Gt. Britain; II figs.. 2 tables, IL refs. Roaring Rails. (in English) B. M. Belgaumkar, J. Sci. Eng. Res. Imdia, 8 (Pt. 2) (1964) 249-256. For abstract see AppL. Mech. Rev., 19 (9) (19Gfd 774. 4.2.
Bearings
Determination of Performance Characteristics of Hydrostatic Bearing Systems that Support a Rigid Body. W. Shapiro, V. Castehi and S. Heller, ASLE Trans., 9 (1966) 2722282. An analysis of a system of hydrostatic bearings used to support a rigid structure subjected to either specified loads or movements is described, and results of sample problems are shown. The governing equations are developed, considering generalized system supply circuitry and arbitrary selection of fixed type compensating elements for each bearing. The equations have been programmed for solution on a high-speed digital computer. The methods of solution and conceptual flow chart of the program are described. From specified loads (or alternatively displacements) of a point on the body chosen as the origin, individual bearing performance parameters, resultant body displacements (or alternatively loads), and the hydraulic system parameters are determined. An Adiabatic Solution for the Finite Slider Bearing (L/B = 1) A. A. Raimondi, ASLE Trans., 9 (1~66) 283-298.
The classical case in lubrication of two flat rectangular surfaces has been solved to account for the variable properties of the lubricant. The effect of varying viscosity and density with temperature has been taken into account by solving simultaneously the Reynolds Equation and the Energy Equation for a square pad (LIB = r) with a digital computer. The case of two insulated plates is used; no heat conduction is allowed. The solutions are compared with the classical theory which assumes the lubricant to have constant properties. Curves showing the pressure and temperature distributions are presented. Design curves are given for the performance of fixed pad bearings, pivoted pad bearings with central pivots as well as optimum pivots, and parallel surfaces. A