Huntingdon Fusion Techniques (HFT®) have developed the HotPurge® Inflatable Pipe Purging System to prevent the oxidation of extremely hot welding zones.
The new invention has been designed for heat treated chrome and high strength stainless steel pipe joints where temperatures can reach 760°C for prolonged periods of time.
HotPurge is manufactured as standard with self-regulating PurgeGate® – meaning that even if excessive rates of argon (Ar) gas flows through, the PurgeGate prevents too much pressure being delivered to the inflatable dams. This allows the increased flow to achieve a lower oxygen (O2) level and faster cooling of the weld zone.
Luke Keane, Distributor Support for the UK-based company, explained, “HotPurge allows the purge to be safely continued for up to 24 hours whilst pre-heating, welding and post weld heat-treating with the purge system remaining in place.”
Each system also includes a RootGlo® band, which can illuminate inside the pipe for up to 20 hours. Additionally, its inflatable seals maintain an even seal throughout the weld cycle irrespective of pressure rises or excessive Ar flow.
The systems also keep O2 levels below 100 parts per million (ppm) throughout the welding cycle, ensuring oxide and coke free welds without metallurgical defects, and have been designed to fit pipe diameters from 6-96” wide.