Weld Purging is the act of removing oxygen within the vicinity of a joint when welding, especially when joining metals such as stainless steel, nickel alloys, titanium, zirconium etc. However, completely filling tubes and pipes with expensive inert gas – such as argon – for weld purging is a time consuming process.
With the aim of avoiding such costly time loss and excessive waste of argon gas, Huntingdon Fusion Techniques (HFT®) has introduced its QuickPurge® tube, pipe and pipeline weld purging systems.
Whatever the size of pipe, QuickPurge systems reduce waiting times and pay for themselves in less than one weld. QuickPurge is simply inserted into a tube or pipe, inflated within the pipe to restrict the area to be welded before oxygen in removed within minutes.
For example, a 36 in. dia. stainless steel pipe can be purged down to 100 parts per million (ppm) of oxygen in under 32 minutes. Comparing this with weld purging using foam dams or other homemade devices that will outgas heavily into the welding zone, taking many hours.
Features of QuickPurge systems include:
- An additional gas input line, allowing extra purge gas to be introduced for high speed purging down to the lowest oxygen levels. This is ideal for larger diameter pipes, where quality welds are required. Extra cold argon gas input helps to mitigate the extra heat produced by the Plasma/TIG process.
- The advanced design of the QuickPurge system means that oxygen levels as low as 10 ppm can be reached every time, allowing zero colour welds to be achieved with no loss of corrosion resistance caused by oxidation.
- IntaCal® combined with the integrated PurgeGate® device makes it possible to safely inflate the systems with argon gas, for sealing and then purging the space between the dams where the weld joint is located.
All of the systems are manufactured with a hose for connecting a Weld Purge Monitor®, which can read oxygen levels down to as low as 1 ppm.
The materials used in the manufacture of QuickPurge are resistant to the higher weld temperatures that are present. Moreover, they do not outgas, thus preventing weld contamination.
For pre-heated chrome steel and high strength stainless steel pipe joints, HFT manufactures the HotPurge® systems for a higher and longer temperature exposure.
Read the article online at: https://www.worldpipelines.com/product-news/02022017/hft-welcomes-new-weld-purging-products/