What I have right now... is that
Syp,SS304=206.8MPa
F=π(.075m)2*206.8E6 = 3.66MN
and relating that to the current thickness we have at 5cm
σ=\frac{3.66MN}{.15m*.05m}=488MPa
And 488MPa < Sut,SS304 with Sut,SS304=517.02MPa
But I'm pretty positive I'm making some logical error here.