Please run the thickness calculations based on the following options:
1) Corrosion Allowance of 1/16 inch on od of the shell and 1/16 inch on the id of the jacket.
2) Corrosion Allowance of 1/8 inch on id of the jacket only.
3) Corrosion Allowance of 1/8 inch on the od of the jacket only.
Once you have those calculations, please send me a copy for review of the material thicknesses required.
Thanks.