API 620 Tank: Hydrotest of new 3" installed nozzles

[Meck91]

We are planning to weld new 3", 300# nozzle on tank constructed to API 620, 6th edition back in 80's. Tank design pressure is 55 kPa (~ 8 Psi).
I am suggesting doing NDE of these nozzles per API 620, 11th Edition, Section 7.15 "Examination Method and Acceptance Criteria". Is NDE is sufficient to check the integrity of weld joints. Also,
I am thinking of performing a hydrotest of theis nozzle only by “CARBER Nozzle Test”. What should be the test pressure in this case? Note that the new tank was Hydro-pneumatic tested to 69 KPa (~ 10 Psig). Should I recommend hydrotest this nozzle at 10 Psig by CARBER or just above NDE per API 620 is sufficient.
Unfortunately, I cannot find any section in API 620 specifically regarding hydrotesting of additional nozzles.

Would highly appreciate your help.

Thanks,

Meck91

 

[fegenbush]

Alterations or repairs to API 620 tanks should follow the procedures outlined in API 653. For addition of a nozzle 12" or less, a hydrostatic test is not required, as it is not considered a major repair. However, if your contract may require testing in excess of the requirements of 653.

 

[Meck91]

Thank You very much for your inputs.