A turnbuckle is needed to apply an 8kN force on a cable. If the efficiency of the turnbuckle is 40% and the force applied is 159.155N with a lever of 20cm in length.
a) Find the mechanical advantage.
Mechanical Advantage=Load/Effort
M.A.=8000N/159.155N
M.A.=50.265 (Ans.)
b) Find the velocity ratio.
Efficiency(ç)=(Mechanical Advantage)/(Velocity Ratio)
V.R.=(M.A.)/ç
V.R.=50.265/0.40
Velocity Ratio=125.66 (Ans.)
c) Find the mean pitch of thread.
V.R.=(Distance moved by effort)/(Distance moved by load)
V.R.=2ðL/(2Xpitch of thread)
2Xpitch of thread=2ðX200mm/126.66
2Xpitch of thread=1256.637/126.66
Pitch of thread=9.921/2
Pitch of thread=4.96mm (Ans.)
To find the mechanical advantage of the turnbuckle, divide the load (8kN) by the effort (159.155N):
Mechanical Advantage = Load / Effort
M.A. = 8000N / 159.155N
M.A. = 50.265
So, the mechanical advantage is 50.265. (Answer to part a)
To find the velocity ratio, divide the mechanical advantage by the efficiency:
Efficiency (ç) = Mechanical Advantage / Velocity Ratio
V.R. = M.A. / ç
V.R. = 50.265 / 0.40
Velocity Ratio = 125.66
Therefore, the velocity ratio is 125.66. (Answer to part b)
Finally, to find the mean pitch of the thread, use the equation:
V.R. = (Distance moved by effort) / (Distance moved by load)
V.R. = 2πL / (2 X pitch of thread)
Rearrange the equation to solve for the pitch of the thread:
2 X pitch of thread = (2π X 200mm) / 125.66
2 X pitch of thread = 1256.637 / 126.66
Pitch of thread = 9.921 / 2
Pitch of thread = 4.96mm
Therefore, the mean pitch of the thread is 4.96mm. (Answer to part c)