Question

The mean diameter of the square threaded screw if a jack is 40 mm and pitch of threads is 8mm find the torque required to raise a load of 20 KN taking
`${\mu}$`

Answer 1

Question :

The mean diameter of the square threaded screw if a jack is 40 mm and pitch of threads is 8mm find the torque required to raise a load of 20 KN taking${\mu}$ = 0.1

$\boxed{<u> </u><u>Answer</u><u> </u>}$

$Diameter = d = 40 mm, P = 8 mm \: \\ </p><p>\mu = 0.1 \: or = tan (\phi) \\ </p><p>W = 20 KN = 20 ×10^3N \: \\ </p><p>tan ( \alpha ) = \frac{P}{\pi \: d} = \frac{8}{3.14 \times 40} = 0.0636 \\ \\ </p><p>Force, \: \: {P}_{1} = W tan (\alpha+\phi) </p><p> = \: W [\frac{tan \alpha + tan\phi }{1 - tan \alpha \: \: tan\phi}] \\ \\ </p><p> = > 20 × 10^3 [\frac{0.636 + 0.1}{1 - 0.063 \times 0.1}] = 3280 N \\ \\ </p><p>Torque \: required = {P}_{1} \times \frac{d}{2} = 3280 \times \frac{40}{2} = 65600 \: N \: mm</p><p>$