Cryo-freezing a 14" water main pipe - video

[Tooler2]

Interesting that they’re not installing a valve in the 14” pipe so future shut downs are a simpler process. I have five plumbers in my extended family and have helped freeze mains supply pipes many times, when the main valve is too worn to shut down the flow. So we would freeze the main then replace the valve. Voila, problem solved.

So how is the pipe frozen?

[hemmjo]

So how is the pipe frozen?

They use special refrigeration unit pumping refrigerant through a collar around the pipe. The collar is in effect the evaporator in the refrigerant system. You can see the braided steel lines running up to that device in the video. Or they may be using liquid nitrogen.