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Ebook Standard handbook of machine design: Part 2

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(BQ) Part 2 book has contents: Journal bearings, belt drives, worm gearing, vibration and control of vibration, cam mechanisms, load cycle analysis, fluid power systems and circuit design, noise and its control, robots and smart machines, deflection,. and other contents. | CHAPTER 27 ROLLING-CONTACT BEARINGS Charles R. Mischke, Ph.D., RE. Professor Emeritus of Mechanical Engineering Iowa State University Ames, Iowa 21A INTRODUCTION / 27.2 27.2 LOAD-LIFE RELATION FOR CONSTANT RELIABILITY / 27.7 27.3 SURVIVAL RELATION AT STEADY LOAD / 27.8 27.4 RELATING LOAD, LIFE, AND RELIABILITY GOAL / 27.9 27.5 COMBINED RADIAL AND THRUST LOADINGS / 27.12 27.6 APPLICATION FACTORS / 27.13 27.7 VARIABLE LOADING / 27.13 27.8 MISALIGNMENT / 27.16 REFERENCES / 27.17 GLOSSARY OF SYMBOLS a AF b C5 C10 / F Fa Feq F1 Fr / L LD LR L10 Exponents; a = 3 for ball bearings; a = 10A for roller bearings Application factor Weibull shape parameter Static load rating Basic load rating or basic dynamic load rating Fraction Load Axial load Equivalent radial load /th equivalent radial load Radial load Integral Life measure, r or h Desired or design life measure Rating life measure Life measure exceeded by 90 percent of bearings tested n nD HI nR R V x Jc0 X Y 0 $ 27.7 Design factor Desired or design rotative speed, r/min Application or design factor at /th level Rating rotative speed, r/min Reliability Rotation factor; inner ring rotations, V = I ; outer ring, V = 1.20 Life measure in Weibull survival equation Weibull guaranteed life parameter Radial factor for equivalent load prediction Thrust factor for equivalent load prediction Weibull characteristic life parameter, rotation angle Period of cyclic variation, rad INTRODUCTION Figures 27.1 to 27.12 illustrate something of the terminology and the wide variety of rolling-contact bearings available to the designer. Catalogs and engineering manuals can be obtained from bearing manufacturers, and these are very comprehensive and of excellent quality. In addition, most manufacturers are anxious to advise designers on specific applications. For this reason the material in this chapter is concerned mostly with providing the designer an independent viewpoint. FIGURE 27.1 Photograph of a deep-groove precision ball bearing with .