The use of Weld Purge Film® for Pipe Purging

PUBLISHED: 04 Aug 15

Weld Purge Film® in use
Weld Purge Film® in use

When tubes and pipes of certain materials, such as stainless steel, titanium, copper nickel and zirconium are welded together it is desirable to purge the oxygen out of the inside of the weld zone to prevent it from reacting with the hot metal and causing oxidation, porosity and corrosion.

Some products available include Inflatable Tube and Pipe Purging Systems PurgElite®, QuickPurge® and HotPurge™. These systems require an open end to enable the system to be retrieved after the weld is finished, meaning it is impossible to use one of these tandem system for closing welds.

To overcome this difficulty Huntingdon Fusion Techniques, HFT® has developed and manufactured Argweld® Weld Purge Film® kits, with water soluble materials that can be used for open assemblies and closing welds. The Film produces an impenetrable purge barrier, but which can easily be washed away when hydrostatically testing the pipe or just by normal wash out.

To obtain a quality purge is not easy and it has been customary to fill pipes with expensive argon gas and keep the gas running at what is thought to be a suitable flow rate for an estimated period of time. In today's climate of ever improving quality control and increasing demands on procedures with traceability, it is inappropriate to use such hit and miss methods to guarantee a satisfactory purge.

It is not desirable to simply pour gas into a pipe assembly in the hope that a good purge and ultimately, a good weld will be achieved. This technique rarely works.

It is so easy to cut a circle of water soluble film and place it a short distance inside each pipe end, before welding, using the Argweld® Super Water Soluble Adhesive™ to ensure a leak tight barrier, keeping the purging volume to the barest minimum.

Argweld® Weld Purge Film® will save operators large costs by minimising gas usage and cutting down dramatically on time taken to make a purge.

After welding, the water soluble film is simply washed away during the standard hydrotest cycle or by simply washing of the pipe interior and dissolved down to molecular level leaving no trace.

Huntingdon Fusion Techniques Limited, UK
Tel: + 44 1554 836 836
Email: marketing@huntingdonfusion.com
Web: www.huntingdonfusion.com

More news from this company:
Safe, fast and low cost pipe freezing with Qwik-Freezer™
Glass fibre Backing Tape gives improved weld root profiles
Special high quality, leak tight welding hose for argon feed
Tight sealing Low Profile Pipestoppers for limited spaces and restricted access
Huntingdon Fusion Techniques HFT® to Exhibit at World Nuclear
Lightweight aluminium plugs for heavy-duty applications
Cut costs, not corners with QuickPurge®
Achieve high quality welds with a close eye on your weld purge
Versatile, lightweight nylon plugs for Weld Purging
Improve weld quality with a low cost Trailing Shield®
Versatile Inflatable Stoppers for pipe plugging and stopping
Improve weld quality with precision ground Tungsten Electrodes
HotPurge®, for weld purging heat-treated chrome and high strength stainless steel pipework
Inflatable Rubber Plugs: lightweight but strong and highly resistant to petrochemicals
Successful titanium welding with Flexible Welding Enclosures®