1. 416 書名： Essentials of Mechanical Engineering Design, 1/E 作者： Shigey Mischke Budynas 書號： MX0398

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5. 420 8-2 Bearing life Common life measure: Number of revolutions of the inner ring (outer ring stationary) until the first tangible evidence of fatigue Number of hours of use at a standard angular speed until the first tangible evidence of fatigue Rate life (90%) -minimum life, L10 life and B10 life Median life is the 50% (or average life)

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7. 422 In above equation: a=3 for ball bearing a=1/3 for roller bearing Catalog rating lb or kN Rating life in hours Rating speed rpm Desired life

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9. 424 Reliability set x=L/L 10 by Weibul distribution Minimum value of the variate Characteristic parameter corresponding to the 63.2121 percentile value of the variate

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11. 426 Along a constant reliability contour (BD) Along load line (AB) But F B =C 10

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13. 428 Equivalent load Axial load Radial load V=1 when inner ring rotate V=1.2 when outer ring rotate V=1 for self aligning bearing Common expression

14. 429 C 0 : basic static load rating

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21. 436 K

22. 437 Damage done by equivalent loads F e1,F e2 and F e3 is In general form Eq. 8-10 can be written as → →

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24. 439 For continue load

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31. 446 αis the half the include cup angle

32. 447 Location of reactions

33. 448 Relating load, life and reliability Solve for x D gives x D =L/L 10 For Weibull model: x0=0, θ=4.48,b=3/2 For roller bearing:

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36. 451 Timken:

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45. 460 Outline of design assessment: 1.Bearing reliability for the load imposed and life expected 2.Shouldering on shaft and housing satisfactory 3.Journal finish, diameter and tolerance compatible. 4.Lubricant type according to manufacturer’s recommendations; lubricant paths and volum supplied to keep operating temperature satisfactory 5.Preloads, if required, are supplied

46. 461 Bearing Reliability For x0=0, θ=4.48, b=3/2

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52. 467 8-11 Lubrication Elastohydrodynamic lubrication Purpose of the antifriction-bearing lubricant: 1.To provide a file of lubricant between the sliding and rolling surfaces. 2.To help distribute and dissipate heat. 3.To prevent corrosion of the bearing surfaces. 4.To protect the parts from the entrance of foreign matter.

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55. 470 Preloading Alignment Enclosures