It is important to purge the welding zone when welding or tack welding stainless, duplex, chrome steel and titanium tubes and pipes. Purging involves an inert gas being used to prevent corrosion, oxidation, discolouration and ensure an effective internal weld profile with no metallurgical defects.
With over 40 years of design and manufacturing experience for tube and pipe weld purging, Huntingdon Fusion Techniques (HFT®) has introduced its PurgElite®. This is the company’s range of low cost tube and pipe purging systems that are designed to achieve a clean, oxide free, zero colour weld.
Each PurgElite features IntaCal®, a purge gas feed device, which means that there is no complicated valve to adjust and set. A centrepiece glow positioning indicator RootGlo® comes as standard to ensure that the system can be positioned accurately inside the tube or pipe.
They do not include metal braiding on the high temperature resistant gas hose connecting the two inflatable dams, which could be welded to the root of a joint or could scratch the internal bore on removal.
HFT’s PurgeGate® valve is available as an accessory. It regulates gas flow and pressure during weld purging to prevent the dams from over inflating and bursting.
Quick connect/disconnect fittings with collets and O-ring seals for gas tight sealing, fitted with anti-release circlip are fitted to all systems in order to prevent parts from accidentally separating inside pipes.
Georgia Gascoyne, CEO at HFT, said: “We recently had a customer who was wasting money due to time and argon gas costs by filling entire pipework fabrications with argon in order to weld the stainless steel pipes in an inert environment. There were several 90o bends in the pipework, so the customer thought filling the whole pipework system was the only option.”
“To save welders the expense of completely filling tubes and pipes with an inert gas, PurgElite systems are available and manufactured to suit pipe diameters from 1 - 24 in. (25 to 600 mm). PurgElite is manufactured with a special spinal tube that is resistant to hot metal up to 300oC and is super flexible to allow movement around 180o bends if necessary. These spinal tubes are made of low outgassing rate materials, so there is no risk of weld contamination.”
Many fabricators still use homemade devices fashioned from foam, wood, metal and rubber. They are wasting vast amounts of money on expensive argon gas and labour by allowing their welders to continue in their old ways.
Read the article online at: https://www.worldpipelines.com/product-news/04112016/hft-introduces-new-purge-tools/