200 kW is to be transmitted by each of two separate shafts. A is running at 300 rpm and B at 350 rpm. Which shaft must have greater diameter?
As power is same,
T_{A} > T_{B}
or
∴
A circular bar AB of length L is fixed at end A and free at B. Torque T is acting simultaneously at B and C. What is the strain energy U stored in the bar?
Torque on part BC = T
Torque on part AC = 2T
For a power transmission shaft transmitting power P at N rpm, the diameter is proportional to
∴
∴
If a shaft is rotating at N revolutions per minute with an applied torque TNm, the power being transmitted by the shaft in watt is
For a circular shaft of diameter d subjected to torque T, the maximum value of the shear stress is
⇒
∴
What is the maximum torque transmitted by a hollow shaft of external radius R and internal radius r?
∴
A solid shaft of circular crosssection is subjected to a torque T which produces a maximum shear stress τ_{s} in the shaft. The diameter of the shaft should be
From the equation of torsion
⇒
The ratio of torque carrying capacity of solid shaft to that of a hollow shaft is given by
where K is ratio of inside to outside diameter?
τ should be same for both hollow and solid shaft
⇒
⇒
∴
A shaft subjected to torsion experiences a pure shear stress τ on the surface. The maximum principal stress on the surface which is at 45° to the axis will have a value of
A solid shaft of diameter, d and length, L is fixed at both the ends. A torque T_{0} is applied at a distance L/4 from the left end as shown in figure given below.
The maximum shear stress in the shaft is
T_{1} + T_{2} = T_{0} ......(i)
From the equation of torsion
T_{1} = 3T_{2 }......(ii)
From equation (i) and (ii)
⇒
and
Shear stress τ ∝T
Therefore maximum shear stress in the shaft witi be due to torque T_{1}.
⇒








