The Isothermal Lubrication of Cylinders

Abstract

h en the hydrodynamic problem of cy linder lubrication is considered, tw o distin ct ty pes of solution emerge. For light loads th e cylinders retain th eir unl oaded geome try; the Marlin solution fo r th is condition is well kn own . Wh en th e contact forces are large, significant elastic deformation may occur ; th e resultin g elastohy drody namic regim e has been ext ensively analyzed in recent years.Equa tion s are now available for the calculatio n of min imum film thi ckn ess in th e "ri gid " and " elastic " situations. In thi s paper com puting m eth ods app ropriat e to each range of conditions are summarized, and th e natur e of th e solutions is considered in some detail . In particular the valid ran ge of application of th e " rigid" and "elastic" film thi ckn ess relation ships is discussed , An inte rm ediat e range of conditions between the "ri gid" and " elastic" regimes is defined .Finally, a chart is present ed to enable a parti cular problem to be located in th e "rigid," " interm ediat e," or "e lastic" zone s.

Temperature—The Key to Lubricant Capacity

“…Some rollers were operated without failure at film thicknesse s, comp uted bot h by the methods of Crook (6 ) and of Dowson and Whitaker (7 ) , considerably less than the undeformed asperity height, and yet others failed when the compu ted thick ness was greater. F igu re 9 is a"plo t of the relation betwee n the maximum contac t The same limitations for oil A as described by unit load in Fig.…”

“…The crit ical temperature for this Series 3 lubr icant was about the same as for the comparable plain mineral oil (A). However, th ere was a substa ntial difference in the surfaces of the rollers run 100 400 temperature and th e film thickness calculated according to Dowson and Whi tak er (7) . When calculated by th e meth od of Crook (6), the relationship was also very similar to F ig.…”

A Study of the Lubrication and Dynamics of Geometrically Perfect, Lightly Loaded, Cylindrical Roller Bearings with Particular Reference to Shaft Loci

“…. (11) where w is the angular velocity of a roller relative to the cage. Both cage and roller slip in lightly loaded roller bearings have been studied by several investigators (3x9).…”

An Advanced Apparatus for the Study of Roller and Cage Slip in High-Speed Roller Bearings

“…This author warned that the analysis was not appropriate to lightly loaded bearings. Boness [1] referred to these operating conditions as corresponding to the "intermediate" lubrication regime, defined by Dowson and Whitaker [11], in which the bearing surfaces are assumed to be rigid and the lubricant piezoviscous. While Poplawski's analytical predictions of slip correlated well with his test results (obtained with a 65 mm bore cylindrical roller bearing operating at a DN value of about one million [3]), they were not in agreement with Harris's predictions.…”