API 650 tank: what is tolerance of Bottom plate out of slope due to welding distortion or shrinkage

[Alirashid]

What is tolerance of Bottom plate out of slope due to welding distortion or shrinkage before and after hydro test.

 

[JStephen]

I don't think there is a specific tolerance. One of the standards (possibly AWWA D100) mentions that out-of-plane deviation of 1% of the radius is not uncommon, but that was not given as a specific tolerance.

 

[Alirashid]

Thanks

So What is the purpose of para 7.3.6.8 if there is no tolerance limit of distortion, It is mentioning that the measurements shall be taken before and after of the hydro test.

 

[JStephen]

I believe that is measuring subgrade movement/settlement below the bottom, not welding distortion in the bottom.

 

[Alirashid]

Thanks for your reference and clarification.