Bab 6- Kilasan aci

Contoh 1

Satu aci bulat padu 4 m bergarispusat 50 mm dikenakan dengan dayakilas sebanyak 2 kNm. Tentukan tegasan ricih maksimum dan sudut piuh di dalam aci.

G = 77 GPa

A solid circular shaft 4 m diameter 50 mm is the torque of 2 kN. Determine the maximum Shear stress and angle of twish in the shaft. G = 77 GPa

PENYELESAIAN

Data Diberi:

L = 4m

D = 50mm

T  = 2 kNm

G  = 77 GPa

Momen luas kedua kutub aci,

                              πD⁴

      J_{aci padu}       =   -------

                                32

                             

                              π (50)⁴

                        =   -------

                               32

     

                        =     613.6 x 10³ mm⁴

                        =     613.6 x 10^-9 m⁴

Tegasan ricih Maximum,

                              T R_max

      t_max            =   -----------           

                                 J                          

                              (2 x 10³ ) ( 0.025)

                        =   ----------------------

                                  613.6 x 10^-9

                        =     81.5 x 10⁶ N/m²

                        =     81.5 MPa _##

Sudut Piuh,

                             T L

      q                =  -------          

                              JG

                                ( 2 x 10³ ) (A)

                        =  --------------------                                                       

                               (613.6 x 10^-9 )(77 x 10⁹ )

                        =     0.169 rad _##