The Pipestoppers® Division at Huntingdon Fusion Techniques (HFT®) have manufactured Qwik-Freezer™ – a portable carbon dioxide (CO2) pipe freezing system.
It is the only CO2 pipe freezing system that is capable of freezing pipes up to eight inches in diameter, but Qwik-Freezer can also produce ice plugs that are reliable and robust for smaller applications.
In order to freeze the desired liquid, a flexible jacket containing a nozzle connected to a cylinder of liquid CO2 is wrapped around the pipe. The CO2 is then injected into the space between the jacket and the pipe at a temperature of -78°C, creating a secure ice plug and effectively sealing the pipe.
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