Answer:
5.6 mm
Explanation:
Given that:
A cylindrical tank is required to contain a:
Gage Pressure P = 560 kPa
Allowable normal stress [tex]\sigma[/tex] = 150 MPa = 150000 Kpa.
The inner diameter of the tank = 3 m
In a closed cylinder there exist both the circumferential stress and the longitudinal stress.
Circumferential stress [tex]\sigma = \dfrac{pd}{2t}[/tex]
Making thickness t the subject; we have
[tex]t = \dfrac{pd}{2* \sigma}[/tex]
[tex]t = \dfrac{560000*3}{2*150000000}[/tex]
t = 0.0056 m
t = 5.6 mm
For longitudinal stress.
[tex]\sigma = \dfrac{pd}{4t}[/tex]
[tex]t= \dfrac{pd}{4*\sigma }[/tex]
[tex]t = \dfrac{560000*3}{4*150000000}[/tex]
t = 0.0028 mm
t = 2.8 mm
From the above circumferential stress and longitudinal stress; the stress with the higher value will be considered ; which is circumferential stress and it's minimum value with the maximum thickness = 5.6 mm
