Answer :
Answer:
0.016 in
Explanation:
1 ft = 12 in. So the radius r = 6 in
3 ft = 36 in
55 ksi = 1000 psi
The longitudinal stress of the vessel can be calculated as the following:
[tex]\sigma_{\phi} = \frac{pr}{2t_{\phi}}[/tex]
where p = 100 psi is the internal pressure, t is the wall thickness [tex]\sigma_{\phi} = 55000 psi is the maximum tensile stress
[tex]55000 = \frac{100*6}{2t_{\phi}}[/tex]
[tex]t_{\phi} = \frac{100*6}{2*55000} = 0.0054 in[/tex]
The hoop stress can be calculated as the following
[tex]\sigma_{\theta} = \frac{pr}{t_{\theta}}[/tex]
[tex]55000 = \frac{100*6}{55000} = 0.011 in[/tex]
As 0.011 > 0.0054 we will pick t = 0.011 as design to withstand the maximum stress. Taking into account of factor of safety design, the appropriate thickness is 0.011*1.5 = 0.016 in