Dimension problem about the length of nozzle installed in vessel

[younghwi]

When i install nozzle at the top of the vessel as showned below,

the length of nozzle is 200 based on sufface of curvature --> see image below.

So does anyone know how can i install the nozzle based on center line of the nozzle?

If i measured the length based on centerline, it is less than 200.

[jleetemec]

Any Update on these? i would like to know as well