Hi Ray,

Thanks for your reply.

I'm not quite agree actually.

for Div.1.
Please refer to ASME VIII,Div.1, Ed 2007, Ad.2009, UG-16(d), UG-37(definition "t"), Appendix-L (Example. L-7.2)

For Div.2,
"3.2.10.2 Pipe and Tube
If pipe or tube is ordered by its nominal wall thickness, the manufacturing undertolerance on wall thickness shall be taken into account. After the minimum required wall thickness is determined, it shall be increased by an amount sufficient to provide the manufacturing undertolerance allowed in the pipe or tube specification."

Further explanation is welcome "Please"

Thanks..