Selected from Soldagem & Inspeção 2015 20(3) 262–274.
In the usual reference works, welding by the keyhole technique has always been associated with welding processes with high energy concentration, such as the laser process or the plasma process. Recent advances in TIG torches are changing how the TIG welding process should be viewed. An example of these recent advances is the torch with the trade name Infocus, the main feature of which, according to its manufacturers, is the capacity for concentration of energy at the electrode tip, by increasing the cooling power of the electrode, which differentiates the Infocus torch from a conventional TIG torch. This concentration of energy allows the Infocus torch to operate by the keyhole technique. Therefore, the aim of the present work is to study the feasibility of employing the keyhole technique with a conventional TIG torch, with the same working conditions as the torch known commercially as Infocus. The tests confirmed that the TIG process can operate by the keyhole technique, without the need for a torch with special characteristics. However, the electrode of the Infocus torch has a longer life, in comparison with a conventional electrode of the same composition, increasing process productivity.
Keywords: Keyhole, TIG, CF-TIG, Infocus
GONZÁLEZ OLIVARES, Erick Alejandro; GONÇALVES E SILVA, Régis Henrique; DUTRA, Jair Carlos (2015): Study of keyhole TIG welding by comparative analysis of two high-productivity torches for joining medium-thickness carbon steel plates. Welding International, v. online, Volume 31, 2017 - doi:10.1080/09507116.2016.1218603