TUBE NEWS TN April 2019 | Page 18

No Draining the Pipe System with Pipe Freezing Eliminating the need to drain long sections of pipe for repairs or modifications and reducing shut down time is now possible with Pipe Freezing Systems. The Pipestoppers® Division at Huntingdon Fusion Techniques HFT® provides a cost saving solution with Qwik-Freezer™, the industry standard portable CO2 Pipe Freezing System. Ron Sewell, Chairman for HFT® said: “Pipelines containing water can be frozen using liquid carbon dioxide for repairs or modifications to be made. Creating a freeze plug is a very cost effective and quick way to perform pipeline maintenance without draining the system, meaning very little or no system downtime. After the work is carried out, the ice plug is simply thawed and the line is restored to full operation.” When the CO2 is injected into the space between the jacket and the pipe, at a temperature of -78oC, the pipe contents freeze and a secure ‘ice plug’ is formed, which seals the pipe. The ‘ice plug’ forms only in a section of the pipe covered by the jacket, so the resulting rise in pressure is very small and there is no damage to the pipe. The technique can be used safely on iron, lead, stainless steel, copper, brass and plastic pipe. “It is also extremely beneficial for pipework where valves need to be changed, in industry sectors such as petrochemical, building and maintenance services, food and beverage, hospitals, water treatment, shipping and aerospace.” Qwik-Freezer™ is available for pipe diameters up to 8” (200 mm). Even for smaller diameter freezes, Qwik- Freezer™ produces ice plugs that are significantly more reliable and robust, capable of withstanding far more pressure than the smaller plugs that other types of systems will produce. By not having to drain systems of liquids to make repairs, the savings made are able to justify the low relative cost of the Qwik-Freezer™ System. A specially designed flexible jacket is wrapped around the pipe at the point where the freeze is required. A nozzle in the jacket is then coupled to a cylinder of low cost liquid carbon dioxide by means of a high- pressure hose. Larger pipe diameters than 8” and the use of anti freeze and rust inhibitors can create the need for the liquid nitrogen (LN2) temperatures of the Accu- Freeze™ System in order to create a pressure bearing freeze plug. . www.huntingdonfusion.com 18 TUBE NEWS April 2019