Calculating Shear Stress in a Flange Coupling with 4 Bolts

[bennetg]

Homework Statement

A flange coupling is use to transmit torque of 1500 Nm between two shafts. The coupling has four 8mm dia. bolts equally spaced on a PCD of 175mm. Determine the shear stress on the bolts

Homework Equations

$fs=\frac{F}{A}$

The Attempt at a Solution

Back of the book answer = 85.3MPa. but I don't know how they get this answer.

 

[bennetg]

It's ok, disaster averted.

Just use t=F*r to convert the torque to a force acting on the bolt's.

Unfortunately TAFE forgot to give me this formula before giving me this question.