Shaft,Keys&SpringShaft,Keys&Springy p gy p g

Shaftisarotatingmachineelementthattransmitsgrotationalmotionandpower

Shaftdesignprocedure1. Determinetherotationalspeedoftheshaft2. Determinethepowerorthetorquetobe

t itt d b th h fttransmittedbytheshaft3. Determinethedesignofthepower

transmission components or other devicestransmissioncomponentsorotherdevicesthatwillbemountedontheshaft,andspecifytherequiredlocationofeachdevicesp y q

4. Specifythelocationofbearings5. Proposethegeneralformofthegeometry

f h h ffortheshafts

PowertransmittedbyshaftPowertransmittedbyshaft

Theworkdonebythetorque:W=T.

is angle of rotation in radians isangleofrotationinradiansPower,Pistherateofworkor:

P=dW/dt=T.d/dtP= T, (rad/s)P T,(rad/s)P=2f.T

Unit:Unit:T(NewtonMeter)P(watts)T(poundfeet)P(poundfeet/second)

USunit:USunit:P(horsepower,H=hp)1h 550ft lb/1hp=550ftlb/s

H=P=2nT/(60.550)=2nT/33000(n=rpm,T=lbft,H=hp)

Maximum shear stress in a shaft:Maximumshearstressinashaft:

Akeyis Anelementusedtoconnectadrivemembersuch as belt pulley, chain sprocket or gear tosuchasbeltpulley,chainsprocketorgeartotheshaftthatcarriesit

A machinery component placed at the Amachinerycomponentplacedattheinterfacebetweenshaftandthehubofapowertransmitting element for the purposepowertransmittingelementforthepurposeoftransmittingtorque

T f ilit t bl d di bl Tofacilitateassemblyanddisassembly Installedinanaxialgroovecalledkeyseat

Square and rectangular keysSquareandrectangularkeys

Key seat dimensionKeyseatdimension

Alternativeofparallelkey

Stressanalysiskeylength

SplineSpline

SpringSpringis a flexible element used to exert a force or a torque, and at the same time to store energyand at the same time to store energy