Gear

·Terminologies, pitch diameter, diametral pitch (teeth per Inch of pitch diameter),module (metric), Wt, Wr (table 14-1)

·Principle: calc. stress due to bending and indentation of Teeth in contact, compare against strengths

·AGMA equations for bending, list of equations In fig14-17

·AGMA Equations for wear, list of equations in fig14-18

·need Lewis Form Factor Y (table14-2)

Shaft

·For fatigue analysis, need endurance limit, uncorrected from Sut (eqn 6-8), corrected by Marin factors (eqn 6-18, and factor eqns 6-19 to6-29)

·Get static stress Concentration factor Kt (normal) and Kts (shear) from geometry (figs. A- 15-x)

·Get fatigue stress concentration factor Kf and Kfs by modifying Kt with the q formula (eqn 6-32) and figs. 6-20 &6-21

Analysis using stresses:

oCalc. Normal stress (tension/compression) σ and shear stress τ, ,midrange (subscript m) and amplitude (subscripta)

oGet von Mises stress amplitude and midrange Stress (eqns 6-55 &6-56)

oApply appropriate fatigue Failure criterion (eqns 6-45 to 6-48) Analysis using moment andtorque:

oCalculate moment M and torqueT

oApply shaft design criterion (eqns 7-7 to7-14)

·Check For 1st cycle yielding txtbk eg 6-14 lastpart

·Design For keys (txtbk eg 7-6 or L23 Key Design Eg1)

Bearings

·Principle - load-life equation: Load × Life(1/a) = constant (eqn 11-2), left Side is the catalogue conditions, right side is the appliedconditions

·Apply Load-Application factor Ka to Load to account for un-smoothapplications

·For combined radial and axial load, use equivalent load Fe in the load-life equation (eqn 11-2, Table 11-1). Only if ratio of axial to radial load greater than e. Iterate to Ensurethat consistency of all Table 11-1columns.

·Apply reliability factor Kr To catalogue life if non-90% reliability is desired (SKF Life Equation page 12, L24 Bearing 2 lecture notes, Kr table Will be provided inexam)

·Remaining life in variable loading (eqn11-16)

Power screw

·Terminologies

·Mechanics Of powerscrew

·????_????, ????_????, efficiency, collar friction (eqns 8-1 to8-5)

Threaded fasteners

·Terminologies, Dimensions table 8-7

·Fastener Stiffness,Eq.8-17

·Member Stiffness, Eq. 8-20, 8-22 and8-23

·Bolt Strength, Table 8-9 to Table 8-11 (SAE, ASTM andmetric)

·Tension joint, static loading only, Terminology and equations txtbk section8-7

·Preload = 0.9 or 0.75 of proofload

·find n Against yielding eqn8-28

·joint Separation, eqn8-30

Welded joints

·Symbols

·Stress: in plane, eqns 9-4 & 9-5 to calc. Shear. Table9-1

·Stress: out-of plane, Table 9-2 eqn d beforeit.

·Strength: Table 9-3 for electrode and Table 9-4 for permissiblestress

·Staticloading

Springs

·Terminologies, Dimensions table10-1

·Spring Shear stress eqns 10-7, 10-5,10-1

·Spring Constant or rateeqn10-9

·Spring Allowable shear stress, Eq. (10-14), Table 10-4, 10-5 and10-6