Transactions

618 TRANSACTIONS OF THE A.S.M.E. OCTOBER, 1941T A B LE 1P R IN C IP A L D IM E N S IO N S A N D R A N G E OF T E S T C O N D IT IO N S FO R B E A R IN G S T E S T E DClearance ratio,mils per in. Top-half-------- diam ----- grooves,— Range of test conditionsz,T est DimensionsHori- w idth Xno. I X d, in. Vertical zontal depth, in. Feed type D rain type p, psi N, rpm centipoises Q, g p m1 3X3 2.0 3 .0 None O n up-com ing side Through ends of lining 57-521 8000 10-13 0 .6- 1.02 3 X 3 2.0 3 .0 13/4 x y «2 On up-com ing side Through ends of lining 57-521 4000-12000 11.5-18 0 .5 -1 .03 3X3 2.0 5 .0 13/4 X VS2 On up-coming side Through ends of lining 57-521 8000 12-18 2 .0 -3 .54 3 X 31/4 2 .5 5 .0 i3A y» On up-com ing side T hrough ends of lining 52-480 4000-12000 6-15 0 .6 -3 .55 3 X 31/4 2.0 5 .0 13/4 y« On up-coming side Through ends of lining 52-480 8000-12000 11.5-18 1 .2 -2 .8 56 3 X 31/4 3 .0 4 .7 13/4 x y«2 On up-com ing side T hrough ends of lining 52-480 4000-12000 6-20 0 .5 -3 .57 4X4 2 .5 3 .0 X i/ie On up-com ing side Through ends of lining 59-775 4000-12000 15-19 0 .9 5 -6 .68 4X4 2 .5 5 .0 2 yw On up-coming side Through ends of lining 59-775 4000-12000 1 0 .6 -1 7 .4 0 .9 -5 .59 6 X 43/4 1.3 2 .5 1 x yw On up-coming side y 2 X x/\ orifice 86-500 3600-6000 7-20 1 .7 -9 .010 6X8 1.3 2 .5 (2) 1 x yis On up-com ing side y 2 X y 4 orifice 51-355 3600 7.5 -1 6 2 .5 -9 .011 8 X 6V4 1.3 5 .0 11/4 x y 32 On up-com ing side Through ends of lining 59-416 3600-6000 6 .5 -1 9 .5 3 .0 -1 5 .5(diagonal)12 8 X 6V 4 1.3 2 .5 i y 4 X y s2 On up-coming side Through ends of lining 60-500 3600-6000 7-15.5 5 .0 -1 6 .0(diagonal)N o t e : Arc of b a b b i t t of loaded surface = 1 2 0 deg — 1 3 0 deg.B R A C K E TF i g . 4Z N Q /p V e r s u s / C u r v e s f o r 8 X G ' / V I x . 1 2 0 -D e g L in in gF ig . 2B e a r i n g T e s t S t a n dvariable, and it was found that, for each value of bearing pressure,the coefficient of friction varied exponentially with ZN/p; inother words a straight-line curve on log-log paper was obtainedfor / versus ZN/p at each value of unit pressure.Later, when the total flow of oil to the bearings was varied, itwas found that for each value of pressure the coefficient of frictionvaried exponentially with ZNQ/p. (It should be understood thatthe flow of oil Q is the total amount supplied to the bearing,which may be more or less than the amount of oil which flowsbetween the journal and lining on the loaded side.) The resultingvalues of / were then plotted against ZNQ/p for various valuesof p, Figs. 3 and 4. It was also found that a cross plot o f/ versusp at constant values ot ZJvy/p gave a straight-iine curve on loglogpaper. Thus, we are led to believe thatfor a given bearing when 1/a and a are constant, as illustrated inFigs. 3 and 4.The cross plot o f / versus p for constant values of ZNQ/p gavea check upon the accuracy of the test results.A detailed discussion of the results of the tests on all the bearingsneed not be given here. However, the results on one ofthe 3 X 3-in. bearings are of particular interest. The first teston this bearing was with 0.006-in. clearance in the vertical planeand 0.009-in. clearance in the horizontal plane and with no groove