Proper Interpretation of Shell Design
Proper Interpretation of Shell Design
(OP)
I have a question regarding the wording of 5.6.1.1 in API 650.
"The required shell thickness shall be greater of the design shell thickness, including any corrosion allowance, or the hydrostatic test shell thickness, but the shell thickness shall not be less than the following:"
Does this mean the indicated minimum thicknesses are prior to adding a corrosion allowance? Or do you add the corrosion allowance to the design thickness, and if the thickness is still less than the indicated minimum, bump it up?
I did a quick search and It doesn't look this has come up before on the forum.
I'm relatively new to the code and any guidance would be greatly appreciated.
"The required shell thickness shall be greater of the design shell thickness, including any corrosion allowance, or the hydrostatic test shell thickness, but the shell thickness shall not be less than the following:"
Does this mean the indicated minimum thicknesses are prior to adding a corrosion allowance? Or do you add the corrosion allowance to the design thickness, and if the thickness is still less than the indicated minimum, bump it up?
I did a quick search and It doesn't look this has come up before on the forum.
I'm relatively new to the code and any guidance would be greatly appreciated.





RE: Proper Interpretation of Shell Design
Ensure you still consider all external loads such as wind, seismic and nozzle loads when considering plate thickness.
RE: Proper Interpretation of Shell Design
Calculate the hydrotest, no corrosion allowance needed.
Read the minimum.
Take the greater of the three.
RE: Proper Interpretation of Shell Design