Roof external welding after hydrotest

[Amirrul]

Dear all,

Can we perform welding repair for roof plate(fixed) after completion of hydrotest?.do we need to re hydro again after repair?. Thanks.

 

[IFRs]

Yes, No. Hydro does not test the roof plate.

7.3.6 Testing of the Shell
After the entire tank and roof structure is completed, the shell (except for tanks in accordance with Annex F) shall be strength-tested and the foundation initially loaded by one of the following methods...

 

[Amirrul]

Thanks IFR for confirmation.

 

[HTURKAK]

No..In case of low pressure tank as per annex F. API 650 Annex F 'F.4.4 When the entire tank is completed, it shall be filled with water to the top angle or the design liquid level, and the
design internal air pressure shall be applied to the enclosed space above the water level and held for 15 minutes. The air pressure shall then be reduced to one-half the design pressure, and all welded joints above the liquid level shall be checked for leaks by means of a soap film...'

 

[IFRs]

HT is absolutely correct. If the OP has an Annex F tank the fixed roof must be complete before hydro.