Hey guys,
I am working an internship and my project now is to design a rear lower control arm for a vehicle. The chromoly tubing has to withstand 6000lbs of compressive force. The length from bolt to bolt is 18.43".
Column Design:
I did Euler and JB Johnson column buckling equations and when solving for OD-ID I just assumed the more common 1-3/8" and 1-1/2" OD for control arm tubing. I get a little different answers from each way, but figure a wall thickness of .120"
Threads Design:
Then I have to figure out a thread callout, for the bung (12L14 material), to tap the inside of this tubing and still be able to withstand the force. I have been doing some calculations with 1-3/8" x 12 UNF thread. I haven't had any Design classes yet with threads so I'm not sure how to really go about this. I need to make sure the thread with withstand the force, and when the tubing is tapped, that it will not weaken the tubing to fail.
Any help will help, whether it be links, equations for threads and forces, or just time taken out to help!
Thanks,
Joe