# Shaft failure

1. Apr 20, 2012

### aortucre

Hey. This is my first post, I'm a Senior in Mechanical Engineering, I will help others as far as I can.

I'm trying to solve the problem from the picture. The shaft is loaded with 2 transverse loads, 2 moments and 2 torques. The critical point is immediately to the left of "B". The material is AISI 1020 HR steel. The shaft has a diameter of 1.00 inch. I'm trying to figure out if the shaft will fail.

As of now I've figured out that I have to obtain the general stress state at point B. My question is, how does the stress at point "C" affect the stress at point "B"??

If there was only 1 moment and 1 torque affecting point "B", that would be an easy problem, but having the other stress is confusing me.

Any ideas?

THAKS!!

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2. Apr 20, 2012

### OldEngr63

Are you concerned about the fact that your shaft is accelerating like a bandit?

3. Apr 20, 2012

### aortucre

The shaft is pinned at A and D. Thanks for your reply!

4. Apr 20, 2012

### OldEngr63

Then why is there a problem? What you need is the sum of all bending moments at the point of interest, not just the moment applied at that point, and the sum of all torques, not simply the torque applied at that point, where you calculate the equilibrium condition for an element at that location.