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Solution for the pressure and temperature in an infinite slider bearing of arbitrary profile
GILBERT, J. B., KARTZMARK, R. AND SPROULE, L. W. Hydrogen processing of tube stocks. Journal of the Institute of Petroleum, 53, No. 526, p. 317, (1967) Three hydrogen treating p r o c e s s e s for refining lubricating oils are described: hydrofining, mild hydrotreating and s e v e r e hydrotreating. Hydrofining is used to finish solventextracted base stocks. A variety of lubricants and speciality products can be manufactured by means of mild hydrotreating and its use for the production of naphthenic oils is described. Severe hydrotreating makes it possible to obtain high-viscosity index oils from raw petroleum feedstocks. For each of these p ro ce s s e s data is presented to illustrate the yields and quality of typical products. Comparison is also made with corresponding products refined by conventional p r o c e s s e s such as clay finishing, acid treating and solvent extraction. (Tribology 1968, abstract 16)
HALLING, J. Analysis of s p i n / r o l l conditions and the frictional-energy dissipation in ang~,l-~--contact thrust ball bearings. P r o ceedings of the Institution of Mechanical Engineers, 181, Part 1,No. 16 (1967) In current analysis of the contact conditions in angularcontact ball bearings, it is assumed that sliding occurs in all regions where tangential surface tractions are operative. However, other work in si m i l ar rolling-contact situations has demonstrated that some of this slip requirement may be accommodated by the elastic surface deformations. This type of analysis leads to areas of sliding and sticking coexisting within the contact areas. These concepts a r e here applied to angular-contact thrust ball bearings and produce some interesting deviations from the results obtained using the complete slip analysis. In particular, these concepts of mieroslip enable the determination of the sp i n / r o l l ratio at each race contact. Detailed calculations for conical thrust ball bearings illustrate the main discrepancy of the full slip analysis on o v er - est i m at i n g the frictional-energy l os s e s , such discrepancies being most marked with decreasing contact angle, increasing pitch/ball radii, and increasing coefficient of sliding friction. (Tribology 1968, abstract 20)
G R A T T E N , P. A. A N D L A N C A S T E R , J. K. Abrasion by lameilar solid lubricants. Wear, I0, No. 6, p.453 (1967) A n experimental technique designed to measure abrasiveness of lamellar solids is described. The apparatus used is a pin and disc machine with the pin mounted eccentrically. Results are given for tests conducted with a variety of grades of molybdenum disulphide, both as dry powder and as a dispersion in silicone fluid, using a bronze pin and a P T F E disc. It was found e a s i e r to interpret the results obtained when using dispersions than those for dry powders. The factors thought to be responsible for the abrasiveness of l a m e l l a r solids are discussed. (Tribology 1968, abstract 17)
HEINEMANN, R. W. AND SCHULTZE, G. R. Studies of fretting wear. 1. The effect of physical variables. Schmiertechnik, Sept-Oct, p. 239 (1967) Fretting wear is frequently not observed until subsequent frictional wear has caused the matching parts to become mutually displaced. This has led to the view that tangential s t r e s s e s cause the entire matching system to be mutually displaced. Evidence is produced that, instead, the initial stage of fretting wear involves only small s t r e s s e s leading to non-elastic twisting or displacement of part only of the G U N T E R , E. J. contact areas. Periodic stressing thus leaves the matching The influence of lubricant compressibility on the perforsystem at rest on a macroscopic scale. Only subsequently, mance of the 120~ partial journal bearing. Transactions of as the contact areas wear further, are further areas exposed the American Society of Mechanical Engineers, Journal of to fretting wear. The t e r m s 'static' and 'kinetic' fretting Lubrication Technology, 89, Series F, No. 4, p. 473 (1967) wear are introduced to describe these fundamentally diffeEffects of the increase of the compressibility parameter ~rent microscopic processes. Their genesis and remedial from 0 to co on the characteristics of the 120 degree bearing measures are discussed. (Tribology 1968, abstract 21) are discussed. Graphs are developed to illustrateunder what conditions the partial gas bearing m a y be treated by the incompressibility theory. For low-compressibility numbers it is shown that the bearing clearance ratio and pivot location can alter considerably and stillremain close to optimum conditions. A discussion is given on the optimum design values of the compressibility number. (Tribology 1968, abstract 18)
HAHN, E. J. AND KETTLEBOROUGH Solution for the pressure and temperature in an infinite slider bearing of a r b i t r a r y profile. Transactions of the American Society of Mechanical Engineers, Journal of Lubrication Technology, 89, Series F, No. 4, p. 445 (1967) A method of calculating the steady-state temperature and p r e s s u r e distributions in the lubricant film of an infinitelywide slider bearing is presented. The method is an iterative procedure and the bearing profile is assumed quite general. Viscosity of the lubricant is assumed to be a function of t e m perature and pressure, and the density is considereed as a function of temperature only. Heat t r a n s f e r between bearing surfaces and the lubricant is considered, also inertia t er m s are included plus a compressive work term. The solution of several examples are derived and the results compared with existing solutions. (Tribology 1968, abstract 19)
HEINICKE, G. AND HARENZ, H. The part played by chemical factors in lubrication by MoS2. Schmierstoffe und Schmierungstechnik, No. 21, p. 23 (1967) The e a r l i e r hypothesis of a physical mechanism to explain the effect obtained during working in of the molybdenum disulphide lubricant has been replaced by postulating a chemical mechanism, as evidenced by fluorescence spectral studies revealing iron sulphide formation on iron surfaces. This tribochemical reaction is confirmed by an experimental technique which avoids a r i s e in temperature by using brief, high-frequency impacts. The very sensitive method used to detect the chemical reaction consists in measuring the catalytic effect of the metal sulphide formed in accelerating the heterogeneous nickel and iron carbenyl formation r e a c tion. First, the additional effect of hydrogen sulphide and of nickel sulphide on this reaction is demonstrated, then a s i m i l a r effect is shown to occur during working in of the lubricant. Graphic evaluation of the measurements is adduced as evidence for substantial substrate-metal sulphide formation. (Tribology 1968, abstract 22) TRIBOLOGY January ] 968
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HALLING, J. Analysis of s p i n / r o l l conditions and the frictional-energy dissipation in ang~,l-~--contact thrust ball bearings. P r o ceedings of the Institution of Mechanical Engineers, 181, Part 1,No. 16 (1967) In current analysis of the contact conditions in angularcontact ball bearings, it is assumed that sliding occurs in all regions where tangential surface tractions are operative. However, other work in si m i l ar rolling-contact situations has demonstrated that some of this slip requirement may be accommodated by the elastic surface deformations. This type of analysis leads to areas of sliding and sticking coexisting within the contact areas. These concepts a r e here applied to angular-contact thrust ball bearings and produce some interesting deviations from the results obtained using the complete slip analysis. In particular, these concepts of mieroslip enable the determination of the sp i n / r o l l ratio at each race contact. Detailed calculations for conical thrust ball bearings illustrate the main discrepancy of the full slip analysis on o v er - est i m at i n g the frictional-energy l os s e s , such discrepancies being most marked with decreasing contact angle, increasing pitch/ball radii, and increasing coefficient of sliding friction. (Tribology 1968, abstract 20)
G R A T T E N , P. A. A N D L A N C A S T E R , J. K. Abrasion by lameilar solid lubricants. Wear, I0, No. 6, p.453 (1967) A n experimental technique designed to measure abrasiveness of lamellar solids is described. The apparatus used is a pin and disc machine with the pin mounted eccentrically. Results are given for tests conducted with a variety of grades of molybdenum disulphide, both as dry powder and as a dispersion in silicone fluid, using a bronze pin and a P T F E disc. It was found e a s i e r to interpret the results obtained when using dispersions than those for dry powders. The factors thought to be responsible for the abrasiveness of l a m e l l a r solids are discussed. (Tribology 1968, abstract 17)
HEINEMANN, R. W. AND SCHULTZE, G. R. Studies of fretting wear. 1. The effect of physical variables. Schmiertechnik, Sept-Oct, p. 239 (1967) Fretting wear is frequently not observed until subsequent frictional wear has caused the matching parts to become mutually displaced. This has led to the view that tangential s t r e s s e s cause the entire matching system to be mutually displaced. Evidence is produced that, instead, the initial stage of fretting wear involves only small s t r e s s e s leading to non-elastic twisting or displacement of part only of the G U N T E R , E. J. contact areas. Periodic stressing thus leaves the matching The influence of lubricant compressibility on the perforsystem at rest on a macroscopic scale. Only subsequently, mance of the 120~ partial journal bearing. Transactions of as the contact areas wear further, are further areas exposed the American Society of Mechanical Engineers, Journal of to fretting wear. The t e r m s 'static' and 'kinetic' fretting Lubrication Technology, 89, Series F, No. 4, p. 473 (1967) wear are introduced to describe these fundamentally diffeEffects of the increase of the compressibility parameter ~rent microscopic processes. Their genesis and remedial from 0 to co on the characteristics of the 120 degree bearing measures are discussed. (Tribology 1968, abstract 21) are discussed. Graphs are developed to illustrateunder what conditions the partial gas bearing m a y be treated by the incompressibility theory. For low-compressibility numbers it is shown that the bearing clearance ratio and pivot location can alter considerably and stillremain close to optimum conditions. A discussion is given on the optimum design values of the compressibility number. (Tribology 1968, abstract 18)
HAHN, E. J. AND KETTLEBOROUGH Solution for the pressure and temperature in an infinite slider bearing of a r b i t r a r y profile. Transactions of the American Society of Mechanical Engineers, Journal of Lubrication Technology, 89, Series F, No. 4, p. 445 (1967) A method of calculating the steady-state temperature and p r e s s u r e distributions in the lubricant film of an infinitelywide slider bearing is presented. The method is an iterative procedure and the bearing profile is assumed quite general. Viscosity of the lubricant is assumed to be a function of t e m perature and pressure, and the density is considereed as a function of temperature only. Heat t r a n s f e r between bearing surfaces and the lubricant is considered, also inertia t er m s are included plus a compressive work term. The solution of several examples are derived and the results compared with existing solutions. (Tribology 1968, abstract 19)
HEINICKE, G. AND HARENZ, H. The part played by chemical factors in lubrication by MoS2. Schmierstoffe und Schmierungstechnik, No. 21, p. 23 (1967) The e a r l i e r hypothesis of a physical mechanism to explain the effect obtained during working in of the molybdenum disulphide lubricant has been replaced by postulating a chemical mechanism, as evidenced by fluorescence spectral studies revealing iron sulphide formation on iron surfaces. This tribochemical reaction is confirmed by an experimental technique which avoids a r i s e in temperature by using brief, high-frequency impacts. The very sensitive method used to detect the chemical reaction consists in measuring the catalytic effect of the metal sulphide formed in accelerating the heterogeneous nickel and iron carbenyl formation r e a c tion. First, the additional effect of hydrogen sulphide and of nickel sulphide on this reaction is demonstrated, then a s i m i l a r effect is shown to occur during working in of the lubricant. Graphic evaluation of the measurements is adduced as evidence for substantial substrate-metal sulphide formation. (Tribology 1968, abstract 22) TRIBOLOGY January ] 968
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