Determine maximum shearing stress in shaft, Mechanical Engineering

Determine maximum shearing stress in shaft: 

A propeller shaft 100 mm in the diameter, is 45 m long, transmits 10 MW at 80 rotation per minute. Determine maximum shearing stress in shaft. Also compute the stress at 20 mm, 40 mm, 60 mm and 80 mm diameters. Demonstrate the stress variation.

Sol.:  

d = 100mm

L = 45m

P = 10MW = 10 × 106  W

N = 80RPM

Τmax = ?

τ20 = ?,  τ 40 = ?,  τ 60 = ?,  τ 80 = ?

By using the relation

P = 2  .N.Tmax/60 watts

10 × 106 = 2  .80.Tmax/60

Tmax = 1193662.073 N                                                                                       ...(i)

For solid shaft    τ = 16Tmax/  d3

τ = 16(1193662.073)/[  (100)3]

τ= 6.079 N/mm2

This is shear stress at outer surface that is;  τ100  = 6.079 N/mm2                                             .......ANS

Now stress is varies linearly along diameter of shaft, the shear stress at inner diameter of

the shaft that is; τ20 =  τ20   × d20/d100  = 6.079 × 20/100 = 1.22 N/mm2

τ100 = 1.22 N/mm2                                                                                                      ......ANS

τ40 =  τ100 × d40/d100  = 6.079 × 40/100 = 2.44 N/mm2

τ40 = 2.44 N/mm2                                                                             .......ANS

τ40 =  τ100 × d60/d100  = 6.079 × 60/100 = 3.66 N/mm2

τ40 = 3.66 N/mm2                                                                              .......ANS

τ40=  τ100 × d80/d100  = 6.079 × 80/100 = 4.88 N/mm2

τ40= 4.88 N/mm2                                                                                .......ANS

Posted Date: 10/27/2012 1:23:42 AM | Location : United States






Your posts are moderated
Related Questions
in orthographic projection why in quadrant is taken in anticlock wise

ismb 600 load capacity length in 8 meter

(a) Illustrate what do you understand by Steering Gear Mechanism ? Describe any one Steering Gear Mechanism. (b) Write short note on Pantograph.

Draw the bending moment diagram and shear force diagram: A cantilever beam of 8 m length is subjected to point loads of 15 kN, 10 kN, 25 kN and 20 kN at distances of 4 m, 2 m,

Discover the torque on the shaft: A steel shaft transmits 105 kW at 160 rpm. If the shaft is 100 mm diameter, discover the torque on the shaft and the maximum shear stress ind

Determine the work done per minute by a punch tool making 20 working strokes min when a 30 mm diameter hole is punched in 5 mm thick plate with ultimate shear strength of 450 MPa i

Determine the maximum bending moment: A 12 m span simply supported beam is carrying a consistently distributed load of 2 kN/m over a length of 6 m from the left end and point

Evaluate the tension in the rope: Determine the tension in the rope. Solution KE of the free-body of flywheel is developed due to (i) work-done by tension T in the rop

Magnetic Susceptibility and Ferromagnetic Substances: Magnetic Susceptibility: The magnetic susceptibility (c) of a substance is defined  as the ratio of the intensity of magn

State the Product Data Exchange Specifications In May 1984, a late night meeting of the IGES Organization Edit Committee was held. The outcome: the Boeing representative was