Shielding gas

About: Shielding gas is a research topic. Over the lifetime, 6697 publications have been published within this topic receiving 58668 citations.

A Study on the Three-Dimensional Analysis of the Transient Temperature Distribution in Gas Tungsten Arc Welding:

Abstract: The transient temperature distribution in the gas tungsten arc (GTA) welding process was analysed by employing a three-dimensional finite element model. In the formulation, the solution domain which moves with the welding heat source was introduced to minimize the number of elements, and consequently the computation time of the three-dimensional program. Since the moving solution domain is small compared with the real weld structure, there are two kinds of boundaries, namely, solid metal-atmosphere boundary and solid metalsolid metal boundary. The heat loss through the solid metal-solid metal boundary was considered through a conduction heat flow and the heat flow through the solid metal-atmosphere boundary through a convection heat flow. As the solution domain moves with the progress of welding, new boundary conditions and new elements were generated in front of the heat source, while some elements disappeared in the rear of it. The initial temperature distribution of the new elements was determined by c...

Advanced consumable electrodes for gas metal arc (GMA) welding of high strength low alloy (HSLA) steels

Abstract: This invention relates to solid, bare, consumable wire electrodes for gas metal arc (GMA) welding of high strength low alloy (HSLA) steels. The electrodes require little or no preheat, interpass and post soak temperature controls. The invention also relates to the method of welding and weld deposits produced therefrom.

A Study on Process Characteristics and Performance of Hot Wire Gas Tungsten Arc Welding Process for High Temperature Materials

Abstract: Hot wire gas tungsten arc welding (HW-GTAW) process is the one where the filler wire is pre-heated close to its melting point before it is fed in to the arc. The effect of HW-GTAW parameters such as welding current, hot wire current and the wire feed rate during welding of super ASS 304H stainless steel tubes were evaluated in terms of heat input, voltage-current (V-I) characteristics and weld bead characteristics such as bead weight and geometry. The results obtained indicate that for a constant welding current, increasing the hot wire current and wire feed rate provides a stable V-I characteristics and higher bead weight. Further, increasing the hot wire current and wire feed rate also provides better or desired weld pool and hence the bead geometry was described in terms of width, penetration depth, area of fusion and toe angle. By utilising the above knowledge, the tube to tube butt welding of SS 304H material was carried out. It was observed that, the weld joint is qualified as per the quality requirement of ASME: Sec IX standard.

Rotary arc-welding method

Abstract: In a rotary arc-welding method which comprises: directing a nozzle substantially vertically toward a weld zone of objects of welding; feeding a consumable welding electrode through said nozzle eccentrically from the center axis of said nozzle toward said weld zone; feeding welding current to said consumable welding electrode to produce an arc between the tip of said consumable welding electrode and said weld zone to weld said objects of welding with each other by means of the arc heat; rotating said nozzle to cause a circular movement of said arc from the tip of said consumable welding electrode corresponding to the eccentricity thereof; and, feeding a shielding gas toward said weld zone to shield said arc and said weld zone from the open air; the improvement characterized in that: the diameter of said consumable welding electrode is limited within the range of from 0.8 to 1.2 mm; said welding current is limited within the range of from 400 to 800 amperes; and, the number of rotation of said nozzle is limited within the range of from 3,000 to 6,000 r.p.m.

Laser beam welding method with a metal vapour capillary formation control

Abstract: The invention relates to a method for welding at least one, preferably two metal parts to each other, by a laser beam consisting in using a laser beam (10), a first gas flow and a welding nozzle provided with an output orifice which is passed through by the laser beam and the first gas flow and in welding the part(s) by melting the metal thereof at a point of the laser beam impact with said weldable part(s) in such a way that a capillary (11) or a key hole (12) filled with metal vapour is formed. During welding, the first gas flow is directed only to the aperture of the metal vapour capillary in a direction perpendicular to the weldable part(s) in such a way that a dynamic gas pressure is produced.