-->//(Power Screws) Example 6.10
 
-->//Refer Fig.6.17 on page 204
 
-->//Yield tensile strength of 30C8 Syt (N/mm2)
 
-->Syt = 400
 Syt  =
 
    400.  
 
-->//Factor of safety fs
 
-->fs = 3
 fs  =
 
    3.  
 
-->//Punched holes diameter d (mm)
 
-->d = 50
 d  =
 
    50.  
 
-->//Mild steel sheet thickness t (mm)
 
-->t = 1.5
 t  =
 
    1.5  
 
-->//Ultimate shear strength of the sheet metal Sus (N/mm2)
 
-->Sus = 375
 Sus  =
 
    375.  
 
-->//Mass density of balls dense (kg/m3)
 
-->dense = 7280
 dense  =
 
    7280.  
 
-->//Mean radius of balls Rm (mm)
 
-->Rm = 500
 Rm  =
 
    500.  
 
-->//Assume screw pitch p (mm)
 
-->p = 8
 p  =
 
    8.  
 
-->//Coefficient of friction mu
 
-->mu = 0.15
 mu  =
 
    0.15  
 
-->//Minimum lead required lmin (mm)
 
-->lmin = 5 * 4
 lmin  =
 
    20.  
 
-->//Unit bearing pressure Sb (N/mm2)
 
-->Sb = 18
 Sb  =
 
    18.  
 
-->//Forward stroke displacement fsd (rad)
 
-->fsd = %pi/2
 fsd  =
 
    1.5707963  
 
-->//Time required for the forward stroke tf (sec)
 
-->tf = 1
 tf  =
 
    1.  
 

Screw

Nominal diameter of the screw(d) = 50.000000 mm

Core diameter of the screw(dc) = 42.000000 mm

Lead of the screw(l) = 24.000000 mm

Nut

Length of the nut(L) = 72.000000 mm

Mass of each ball(m) = 52.421082 kg

Diameter of each ball(dia) = 239.584467 mm