Tribology in Machine Design 2009 Part 9 ppsx

... shown in Fig. 7.12, the ball is rolling about axis OA, and true rolling occurs at the inner-race contact B 246 Tribology in machine design (i) the applied load MK producing ... to ensure satisfactory operation cylinders of .engineering surfaces in sliding contact. Even surfaces in nominal rolling contact, such as ball-bearings, normally experience some m...

Ngày tải lên: 11/08/2014, 18:21

... low-running clearance when the bearing is fitted to a machine. However, it is important to bear in mind that running a bearing with no internal clearance at all can lead to thermal instability ... is readily accomplished since they are usually operating in the cryogenic working fluid. In cryogenic systems where radiation may also be present, 280 Tribology...

Ngày tải lên: 11/08/2014, 18:21

... be determined by examining the plasticity index, \\i. However, in the mixed lubrication regime in which /I is in the range 1.0-3.0, where most machine sliding contacts or sliding/rolling ... is particularly true in the case of the adhesive wear resulting from direct metal-metal asperity contacts. If lubricant molecules remain attached to 38 Tribology in...

Ngày tải lên: 11/08/2014, 18:21

... wear in lower kinematic pairs 105 the fact that when a>0 the machine will not sustain the load when the effort is removed. Thus, referring to the inclined plane, Fig. 4 .9, ... the shear stress in the film and Vis the relative sliding velocity. If all the friction work is converted into heat, then Figure 3.5 90 Tribology in machine design st...

Ngày tải lên: 11/08/2014, 18:21

... principle of uniform displacement outlined in case C. In other words, we have the case of a journal rotating in a bush under ideal conditions of wear. 108 Tribology in machine ... either to bring a machine to a state of rest, or to maintain it in a state of uniform motion while still under the action of driving forces and couples. In engine...

Ngày tải lên: 11/08/2014, 18:21

... established in the following areas: (i) Machine tools. Use of gas lubrication in grinding spindles allows attainment of high speeds with minimal heat generation. Sliding-element bearings 199 bearing. ... bearings have been designed with a reduced 212 Tribology in machine design more serious situation exists for the self-acting gas bearings during the period...

Ngày tải lên: 11/08/2014, 18:21

... 298 Index Viscous hydroplaning, 158 Wear rate, 13 Viscous shear, 210 Worm gears, 12 Wear in mechanical seals, 164 Yield strength, 14, 21 292 Tribology in machine design Cose ... rising slowly with further increase in velocity. There is, however, one important difference in the lubrication mechanism operating in plain journal bearings and in gea...

Ngày tải lên: 11/08/2014, 18:21

... fluctuating loads on cylindrical bearing films is more difficult to analyse. Squeeze-film action is important in cushioning and maintaining a film in linkage bearings such as those joining the ... Misalignment of machines, however, cannot usually be anticipated in the design of seals for general industrial use. Misalignment can be designed into either the mating ring, the primary...

Ngày tải lên: 13/08/2014, 05:21

... established in the following areas: (i) Machine tools. Use of gas lubrication in grinding spindles allows attainment of high speeds with minimal heat generation. 196 Tribology in machine design ... bearing arrangement, case (a). If n' = 20, as for the inner film of case (d), then for the same load number 190 Tribology in machine design increasingly eccentr...

Ngày tải lên: 13/08/2014, 05:21

... the practising designer: ESDU-78026, Equilibrium temperatures in self-contained bearing assemblies; Part I - outline of method of estimation; 58 Tribology in machine design integrals ... Press, 195 0, 196 4. 6. I. V. Kragelskii, Friction and Wear. Washington: Butterworth, 196 5. 72 Tribology in machine design contacts, consists of fatigue cracks which pro...

Ngày tải lên: 13/08/2014, 17:20