nozzle and Reinforcement Pad acceptance criteria

[sokapo]

is there any reference for the acceptance criteria for the thickness of nozzle and Reinforcement pad(roof and shell) of a storage tank, after the tank have been in service for some time?

 

[gr2vessels]

sokapo,
If you are checking an existing tank, you have to refer to the design code used for that tank. You have to inspect and measure actual thicknesses, refer to the general API 653 requirements.
If you intend to modify an existing tank (adding nozzles), then again refer to API Std 653, Clause 9.8 and have handy the API 650.
cheers,
gr2vessels

 

[IFRs]

If you are new to the API tank world you may want to solicit the help of an expert for a variety of cost and risk based reasons.