RT on Bottom Annular plate requirement

[WorleyP]

Need your assistance on the interpretation of the API 650 code regarding RT requirements on bottom
annular butt joints.

Please advise if my understanding is correct that no RT is required if the material falls to Group I-III
materials as per API 650 - Table 4.4a.

Appreciate your help.

 

[Duwe6]

If your annular plates are 'required' by 650, i.e. large diameter tank, then the RT requirements of 8.1 are mandatory. IF there was no requirement for an annular ring, AND the plates are Group I to III steel, RT is not mandatory. However, in North America, it would be tough to defend refusal to RT ring plates in court. Some RT of Annular Ring plates is 'Usual & Customary', even when not mandatory per 650.

 

[WorleyP]

Thank you Duwe6 for your help.

So, if the tank requires an annular plate regardless of its material group,

RT requirement of 8.1.2.9 will be mandatory.

 

[Duwe6]

Correct.