Retrofitting a vertical tank to receive a dimple steam jacket 1

[nejenrod]

Specs:
Vertical Atmospheric Storage Tank
Built 7/14/1969
Shell- 20-91/2" seam to seam x 120"I.D. x 3/16" thick
Bottom Head- 120-3/8" O.D. x 1/4
Top Roof- 85.7 sq. ft. x 3/16
All three components are 304 s/s

The bottom head is welded to (8)4" Sch 40 pipe c/s.

New project is to store raw material that must maintain a temperature of 375oF.
The project team feels internal coils or half round jackets are not an option.
They want to weld a dimple steam jacket to encompass the shell and bottom head.

Question:
#1 Can the thin shell plating handle a dimple jacketing welded to it?
#2 Does maintaining that high heat create problems for the 304 s/s?
#3 Is there a better way to heat this tank?

 

[RVAmeche]

I haven't dealt with retro-fitting a dimple jacket onto a vessel but it doesn't seem like a good idea. The jacket vendor or someone will have to tell you the wall thicknesses are sufficient. A pressurized jacket would be an external pressure on the tank that it wasn't designed for. The temperature rating is also much higher. I'd be inclined just obtain a new tank that comes with a jacket. Otherwise retrofitting an internal electric heater may be a viable option.