Down-hole sizes

[willow]

Hello everyone,
I am relatively new to the petroleum industry and have recently been tasked with developing a line of annular ring sight windows for inspecting down-holes. I have already successfully developed the process and techniques for fusing our annular glass rings(borosilicate) to a variety of steels and compliant to NACE MR0175 standards. But now I need to know what the different down-hole sizes there are in the petroleum/oil industry in order to design these properly. Does anyone happen to know if there are some industry standard down-hole sizes?
Did I post this in the wrong section?
Thanks for all your help.

[willow]

It seems that what I am looking for is the different production tubing sizes.
from doing basic research i found that it can range from 5 to 10 cm but I need actual numbers.
Any help is greatly appreciated