Huntingdon Fusion Techniques (HFT®) now manufactures Argweld® quick purge systems with glass treated silicone cloth that can resist temperatures up to 760ºC.
High strength steel joints must be pre-heated prior to welding and also require a post-weld heat treatment. Weld joints of this nature are often purged of oxygen and welded in an inert atmosphere to reduce the risk of ‘sugaring’, an imperfection that could allow metal pieces to break off inside pipework and cause damage to turbines.
HotPurge® has been developed by HFT, as an Inflatable pipe purging system for heat treated chrome and high strength stainless steel pipe joints where temperatures can reach 760ºC (1,400ºF) for many hours.
Luke Keane, Distributor Support for HFT said, “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”
HotPurge includes PurgeGate®, a revolutionary device to prevent over inflation of, and damage to the inflatable dams. No matter how high the user increases the pressure, in order to deliver more gas flow, PurgeGate prevents too much pressure being delivered to the inflatable dams, allowing an increased flow, to achieve a lower oxygen level or faster cooling of the weld zone.
Additionally, HotPurge ensures the purge space remains tightly sealed at all times as the inflatable dams maintain an even seal throughout the weld cycle, irrespective of pressure rises or excessive flow rates of argon (Ar) gas. The large central collar dramatically reduces the space to be purged and makes it easier to reach lower oxygen levels faster than with conventional purging systems.
These inflatable pipe purging systems can be used repeatedly for weld purging and will keep the oxygen levels well below 100 parts per million (ppm) throughout the welding cycle, ensuring oxide and coke free welds, without the metallurgical imperfections caused by exposure to too much oxygen.