Pipe Freezing

Pipe Freezing: Isolating a section of pipe by freezing the contents to form an ice plug.

Pipe Freezing is the state of the art method of freezing liquid pipe contents so that it forms an ice plug. The adhesion of ice to metal allows this plug to hold back the product to allow modifications to made to the existing system.

The freezing chamber is installed on the pipeline. The chamber is sealed to the pipe with special tape to contain the liquid nitrogen that will be injected. (Figure 1 – Left Picture)

Liquid nitrogen is injected and the pipeline monitored. When an ice plug is formed, the necessary modifications are made. (Figure 2 – Middle Picture)

When the modifications are complete, the injection hoses are removed, as well as the monitoring equipment and the freezing chamber. Your pipeline is returned to its original condition. (Figure 3 – Right Picture)


Koppl Pipeline Services’ method of Pipe Freezing sometimes causes concern to those individuals that have dealt with ruptured piping due to freezing. Ruptures occur when the ice plug forms, expands and causes pressure to build between the plug and a dead end. The pipe ruptures when the pressure builds beyond its designed pressure rating. Testing has indicated that radial expansion of the ice plug does not exert nearly enough stress on normal piping to cause failure. Koppl Pipeline Services’ experienced technicians take special precautions against this situation and can assure you a safe completion to your project.

Relief fittings are placed between the Freeze Chamber and a dead end and a pressure gauge is installed to monitor the buildup of pressure in the pipeline. Koppl Pipeline Services ice plugs can hold amazing amounts of pressure. With the natural adhesion of ice to steel and the “hourglass” effect, the ice plug can hold as much pressure as your pipeline. The “hourglass” occurs during the freezing process and temporarily reduces in diameter at a localized area inside our chamber. The plug conforms to the shape and locks itself into position.