API 650 Two-Side Welding

[JXWu]

Dear experts,
Is it a API 650 requirement that the second side of a double-side welded joint needs to be back-chipped at least one-third of the joint thickness?
I cannot find this requirement in the API 650 12th edition. Need advice.
Thanks

 

[Dhurjati Sen]

Dear JXWu,

Are you constructing a double-walled dome roofed tank?

Regards.

DHURJATI SEN
Kolkata, India

 

[JXWu]

This is a API 650 single wall cone roof tank