HW6 Tips and Answers 

HW6.1
The P/A axial stress would go from a max of 211 MPa (tension) to a min of -33 MPa (compression).
For axial loading, Se would be 282MPa.  The proportional FOS would be 1.74.


HW6.2
The Assembly Wrench sees a bending moment of 60 FtLb = 720 InLb when it applies the torque.  Se should
come out to 28.5ksi.  Max stress will be 30.0ksi and the min stress is zero.  The proportional FOS is 1.265.

The Repair Wrench sees a bending moment of 85 FtLb, resulting in a bending stress of 42.6 KSI in alternate 
directions as the bolts are first removed, then replaced.  Se is the same as above.  a = 92.34ksi.  N = 8990 cycles.


HW6.3
The ball weighs 1.18Lb.  Im = 332.2. DeltaMax = 0.654in.


1) Everything that you need should be in the lecture notes.
2) Definitely draw the S-N diagrams.