Hole on Blind Flange 16.5 for auxilarry connection

[dungun]

Hi
Any restriction to tap 1/2" or 3/4" on the blind flange?. What is the require for tapping.

 

[jte]

dungun-

Assuming you are referring to a B16.5 flange. In that case you have no restrictions provided that the blind is at least 2" NPS. See B16.5 section 6.8 and Table F6.

jt