Would grade 30 chain be sufficient for a lightly used practice stage that will only have one bot on it?
I hammock camp (make my own suspension) and while I have not broken out all the math, I am pretty confident it is strong enough for a one, maybe 2 bot hang.
Treating it as a basic statics problem, (ignoring the mass of the chain and pulling the “slack” of the catnary out) results in 5.47kN for 450lbs of robot hanging from the middle as a point mass. Reality is a bit more complex than that of course.
The absolute low end of my quick look online put the yield strength of 3/16" grade 30 at 1300 lbs ( 5.7 kN)
You should be fine as long as you don’t abuse it with shock loading or any other dynamics that send loads through the roof. Obviously the chain is different dimensions, so hooks may behave differently.
Thanks for the confirmation!
We will not place any bouncy bots on it. Hopefully no kids under it either! 
Good plan.
Keep in mind for 450lbs of static robot: there is ~somewhere~ in the neighborhood of 8kN pulling inwards on the field element, so make sure the frame this chain is attached to can handle that.
