API 650 5.6.1.2 1

[tlg588]

Greetings,

Can someone tell me the reasoning behind the 72" minimum width requirement in this section? And why 48" is an allowable minimum for SS? I would like to understanding what is driving the requirement.

I understand that the requirement can be overridden with customer approval.

Thanks for the help.
Tim

 

[JStephen]

That kind of thing comes from somebody's idea of "good practice". It's not like the tank is going to fall down if you use 71" wide plate.
Generally, less welding instead of more is good, less opportunity for problems, less weld distortion. That has to be balanced against material, labor, and freight costs, though. With smaller plates, it also becomes harder to maintain weld clearances.