Weld purging a variety of pipes of different diameters can prove complex and costly, particularly when whole pipework systems need to be filled with expensive argon gas. One solution traditionally used by welders is to construct homemade foam or paper dams that are placed either side of the weld, constricting the purge volume to make weld purging times shorter.
Homemade foam or paper purge dams have severe technical limitations however, that can lead to loss of welds when they leak or slip from position, thus flooding the welding zone with oxygen.
To overcome these challenges, weld purging experts Huntingdon Fusion Techniques HFT have designed and developed Argweld Weld Purge Film Kits to make weld purging affordable and successful.
Georgia Gascoyne, CEO for HFT, said: “Using our low cost Weld Purge Film Kits can save welders both time and money, ensuring oxide-free welds are achieved time and time again.”
“This water-soluble Weld Purge Film allows dams to be cut easily with the safety knife provided and once they are fixed into position using the water-soluble Weld Purge Super Adhesive provided, produce an impenetrable purge barrier that can easily be washed away during hydrostatic testing of the pipe or just by normal wash-out.”
Weld Purge Film Kits can be used on pipe diameters up to 900 mm (36”) and for temperatures up to 300ºC (572ºF) without the material burning and losing the weld purge.
These low cost Kits will save operators high costs by minimising gas usage and dramatically reducing the time taken to make a purge. Weld Purge Film Kits have been designed and developed by HFT. They contain product accessories needed to manufacture dams that will not come loose during welding.
A range of benefits
The technical advantages of using water-soluble film instead of other materials include:
- The total transparency of the film dams allows the welder to see the weld root as it is being laid.
- Vapour pressure of the film is very low and does not outgas harmful elements during welding that can mix with the hot metal and cause metallurgical defects.
- The Argweld Film does not contain water, like paper and sponge products do.
After welding, the water-soluble film is simply washed away during the standard hydrotest cycle or by flushing of the pipe interior, and dissolved down to molecular level, leaving no trace.
This article was written by Michaela Reay, Huntingdon Fusion Techniques.
For more information visit www.huntingdonfusion.com