1. Design of Vessels Under External Pressure
Vessel Design
Design of Vessels Under External Pressure

2. Design of Vessels under External Pressure
Design of Shell: “k” can be get from the following graph:

4. Design of heads:
Hemispherical head:
Dished head:
Elliptical head:

5. Conical bottom:
Get the thickness of the conical bottom from:

6. Sheet 2
A Vacuum crystallizer of 1.25 m inside diameter is to be fabricated from mild steel (σall = 1000 Kg / cm2). Conical bottom with a height of 1.1 m is to be fabricated; the shell is 3.25 m in length. The crystallizer is to be designed for full vacuum service.
Calculate:
i-Thickness of the shell.
ii-Thickness of the conical bottom.
iii-Thickness of the top head (Dished head).

7. Design of jacketed vessels

8. Jacketed vessel Operation Preheating Steam Shut Down 12 psi 0 psi
Vessel : Under internal
12 > 8
Vessel : Under External
8 > 0
Vessel : Under internal
12 > 0
Jacket : Under internal
8 > 0
Jacket : Under internal
8 > 0
Jacket : Under internal
0 = 0

9. “Jacket” under internal
“Vessel” under internal
(any one of them)
under external
Take
tsh
& th

10. Jacketed vessel Operation Preheating Steam Shut Down 5 psi 0 psi 5 psi
Vessel : Under External
10 > 5
Vessel : Under External
10 > 0
Vessel : Under internal
5 > 0
Jacket : Under internal
10 > 0
Jacket : Under internal
10 > 0
Jacket : Under internal
0 = 0

11. “Jacket” under internal
“Vessel” under external
(with Pact )
under internal
Take
tsh
& th

12. It is required to design a jacketed vessel which will be placed indoor
It is required to design a jacketed vessel which will be placed indoor. The vessel has an internal diameter of 1.5m, length of 3m and the jacket has an internal diameter of 1.8 m. The maximum operating pressure in the vessel is 22 Kg / cm2 and the working temperature is 150ºC.The steam passes in the jacket with a pressure 11 kg / cm2 for heating purpose. The vessel and jacket are fabricated from carbon steel with σall =1000 Kg / cm2.
Calculate:
i-Thickness of the vessel and its bottom.
ii-Thickness of the jacket and its bottom.
Note: the type of bottom heads is elliptical.