How to Jump a Nitrogen Line? 2

[mjb1855]

I need to put check valves and flow meters into my nitrogen lines and they cannot be down for very long. I'm going to cold seal them back together but does anyone know a good way to keep nitrogen flowing while I cut out a piece of pipe and insert what I need?

 

[11echo]

How large is your N2 piping? ...And what is the ANSI rating?

 

[Chance17]

Well --
1) You can hot tap upstream of desired meter and install a branch valve
2) you can hot tap downstream of desired meter and install a branch valve
3) you can install a bypass line between the branches and open to operation.
4) you can stopple the main line downstream of hot tap 1
and install a valve downstream of stopple
5) you can stopple the main line upstream of bypass 2
and install a valve upstream of stopple.
6) Install the check vlve a flow meter between the two main line valves.

Admittedly, the multisteps are not very convenient
The only real issue is the size of the byass line.
It will likely be 1-2 pipe sizes less than the main line size.
There are people that argue a full size hot tap is ok for non-flammables.
The bypass size depends on what your safety people will endorse.