Impact Test Requirement for Welds of API-650 Storage Tank when Design Metal Temperature is below -7° 4

[Sarahm554]

Dear All,

A Fuel Oil tank has been designed as per API-650 code and it is mentioned in this code that when design metal temperature is below -7°C impact test shall be carried out for all welds for all components. The statement in code is given as:

"9.2.2.2 When the design metal temperature is below -7°C (20 OF), impact tests of the weld metal shall be made for all procedures used for welding the components listed in 4 2.10 1, for welding attachments to these components, and for fabricating shell nozzles and manholes from pipe and forgings listed in 4.5.

In our case, design metal temperature is below -7°C i.e. -10°C but still welding engineer is insisting that impact testing is not required as per ASME Section IX (QW-403.5).

My question is that Tank is designed as per API-650 and there is no reference that ASME section IX would supersede the above statement of API-650 where impact testing shall be carried out when Design Metal Temperature is below -7°C.

Can anybody guide on this subject.

Thanks in advance

 

[IFRs]

Note that these impact tests are only for the weld procedure, not the actual welds on the tank. Does that help?

ASME Section IX does not supersede API 650 for 650 tanks.

If the manufacturer wants to put an API nameplate on the tank, his work must comply with the entire code, no exceptions unless the owner agrees. If they still resist, and the owner finds the exception acceptable, the name plate should have a note "section 9.2.2.2 not complied with" or something similar. If they want to build you a tank per ASME and you find that acceptable, they can put an ASME name plate on the tank but not an API 650 one.

If you represent the owner, and the manufacturer is giving you trouble, put your foot down and require compliance with API 650 in accordance with your contract with them.

 

[weldstan]

ASME Section IX does not address the design temperature at which impact testing must be performed. The design Code (API 650) does. In your case API 650 trumps ASME IX just as ASME B31.3 and ASME VIII do in that regard.