ASME U2 stamp and singed UDS

[Alireza Moein]

Dear all
our company as an EPC contractor singed a contract with a vendor in order to manufactured a Gas dryer and let us have U2 stamp on it. the vendor asked us to issue UDS singed by AI inspector(user Design Specification singed by AI). now there are two question which need to be answered:
1- is it necessary to issue a singed UDS in order to have U2 stamp?
2- how can we have AI stamp on our UDS?

 

[AWDMIKE]

Hopefully someone with more 2017 Division 2 experience will respond herein, but to my knowledge there are now two classifications within Division 2, both of which requires a UDS to be developed but only one of which needs to be stamped by a certified engineer.
I believe the answers to your questions are 1) both classes need a UDS but only one needs to be signed/certified and 2) I have never seen an AI provide any signature/stamping on the UDS. If anything, the engineer in responsible charge of the UDS should be the one signing/certifying (again, if needed by classification) and not the AI.

Link

 

[TGS4]

To specifically answer your question:
1) Yes - a UDS is required. For Class 1 the UDS does not need to be certified, unless a fatigue analysis is required and the User is providing the data necessary for that analysis, as described in 2.2.2.1(f)(1) and 2.2.2.1(f)(2). For Class 2, the certification of the UDS is mandatory in all situations.
2) It is the engineer who takes professional responsibility for the UDS (meaning that they have been involved in the development of it) that certifies the UDS. The AI has no involvement in the UDS, other than to validate that one exists and is certified in accordance with the requirements in 2.2.1.

Your vendor is incorrect about the AI "signing" the UDS.