Double Freezing technique for large diameter Valve replacement
Replacing valves in a pipeline can be a challenge, especially when the pipelines have liquids running through them. One option is to completely drain the system to make the repairs, which can prove costly with respect to loss of expensive fluid, heating or cooling costs, security matters, time that system is down plus labour costs.
Pipe Freezing Experts Huntingdon Fusion Techniques HFT® recently introduced the Qwik-Freezer™ Systems to their Pipestoppers® Division. These systems create ice plugs or freeze seals in the pipes, avoiding the requirement to drain systems.
Qwik-Freezer™ is the industry standard portable CO2 Pipe Freezing System, in use around the World, covering pipe diameters from 3/8” – 8” (9 – 200 mm).
The quick and easy to use system requires very little set-up time and is the only CO2 Pipe Freezing System capable of freezing larger pipe diameters.
Georgia Gascoyne, CEO for Huntingdon Fusion Techniques HFT® said: “Qwik-Freezer™ has become the preferred solution for a wide range of water-carrying 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.”
Once liquids have been brought to a standstill, 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 liquid carbon dioxide by means of a high-pressure hose. For valve replacement, a second jacket is installed on the other side, creating a double freeze, blocking flow on both sides of the valve.
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 the 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 itself. The technique can be used safely on iron, steel, lead, stainless steel, copper, brass and plastic pipe.
Huntingdon Fusion Techniques HFT® have an Exclusive Distributor network, which can be found at: www.huntingdonfusion.com.