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//Function to round-up a value such that it is divisible by 10
function[v] = round_ten(w)
v = ceil(w)
rem = pmodulo(v,10)
if (rem ~= 0) then
v = v + (10 - rem)
end
endfunction
//Obtain path of solution file
path = get_absolute_file_path('solution6_10.sce')
//Obtain path of data file
datapath = path + filesep() + 'data6_10.sci'
//Clear all
clc
//Execute the data file
exec(datapath)
//Calculate force required to shear the sheet W (N)
W = (%pi * d * t * Sus)
//Compressive stress in the screw sigmac (N/mm2)
sigmac = Syt/fs
//Core diameter of the screw dc (mm)
dc = ((4 * W)/(%pi * sigmac))^(1/2)
dc = ceil(dc)
//Obtain the correct number of starts for the screw n
for n = 1:1:%inf
//Calculate the lead of the screw l (mm)
l = n * p
if (l > lmin) then
break
end
end
//Obtain the correct nominal diameter d in multiples of 10 (mm)
for d = dc:1:%inf
d = round_ten(d)
//Calculate the mean diameter of the screw dm (mm)
dm = d - (0.5 * p)
//Calculate the lead angle alpha (degree)
alpha = atand(l/(%pi * dm))
//Calculate the angle of repose (fi)
fi = atand(mu)
//Calculate the torque required Mt (N-mm)
Mt = (W * dm * tand(fi + alpha))/2
//Calculate the new core diameter dcNew (mm)
dcNew = d - p
//Calculate the stress in the screw CNew (N/mm2)
CNew = ((W * 4)/(%pi * (dcNew^2)))
//Calculate the torsional stress tau (N/mm2)
tau = (16 * Mt)/(%pi * (dcNew^3))
//Calculate the maximum shear stress tauMax (N/mm2)
tauMax = (((CNew/2)^2) + (tau^2))^(1/2)
//Calculate the afctor of safety fsNew
fsNew = ((50/100)*Syt)/tauMax
if(fsNew > fs)
break
end
end
//Calculate the efficiency of the screw eta (%)
eta = (tand(alpha)/tand(fi + alpha))*100
//Calculate the number of threads z
z = (4 * W)/(%pi * Sb * ((d^2) - (dcNew^2)))
z = ceil(z)
//Calculate the length of the nut L (mm)
L = z * p
//Calculate the shear stress in the screw tauS (N/mm2)
to = p/2
tauS = (W/(%pi * dcNew * to * z))
//Calculate the shear stress in the nut tauN (N/mm2)
tauN = (W/(%pi * d * to * z))
//Calculate the work done by the punch work (J)
work = (W * (t/2))/1000
//Work done by balls workB (J)
workB = work/(eta/100)
//Calculate the average angular velocity wavg (rad/s)
wavg = fsd/tf
//Calculate the maximum angular velocity wmax (rad/s)
wmax = 2 * wavg
//Calculate the mass of the one ball m (kg)
m = ((workB * 2)/(((Rm/1000)^2) * (%pi^2)))/2
//Calculate the diameter of the ball dia (mm)
dia = ((m * 6)/(%pi * dense))^(1/3)
//Print results
printf('\nScrew\n')
printf('\nNominal diameter of the screw(d) = %f mm\n',d)
printf('\nCore diameter of the screw(dcNew) = %f mm\n',dcNew)
printf('\nLead of the screw(l) = %f mm\n',l)
printf('\nNut\n')
printf('\nLength of the nut(L) = %f mm\n',L)
printf('\nMass of each ball(m) = %f kg\n',m)
printf('\nDiameter of each ball(dia) = %f mm\n',dia*1000)
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