Arc welding

About: Arc welding is a research topic. Over the lifetime, 25393 publications have been published within this topic receiving 168182 citations.

Pulse arc welding method

Abstract: In pulse arc welding, a welding wire (1) is fed at a rate corresponding to a current average set value (Iar). An arc (3) is struck by passing a peak current (Ip) for a peak period (Tp) and a base current (Ib) for a base period (Tb), where the peak and base periods (Tp,Tb) make one pulse period (Tf). The arc (3) transfers a droplet (1b) from the wire (1). The peak period (Tp) includes a first peak period (Tp1) for a first peak current (Ip1) and a second peak period (Tp2) for a smaller second peak current (Ip2). The first peak period (Tp1) and current (Ip1) are determined so that an arc anode point (3a) is formed at the top of the droplet (1b) even if the shield gas mixing ratio deviates from a standard value. The second peak period (Tp2) and current (Ip2) are determined so that one droplet (1b) is transferred during every pulse period (Tf), and beads are formed with no undercuts.

Apparatus for connecting metallic parts by means of arc fusion welding

Abstract: An apparatus for connecting metallic parts, and metallic parts so produced, by means of arc fusion welding by producing a low volume welding seam (narrow gap welding), wherein the workpiece parts to be joined and forming a narrow gap are initially welded at their butt joint by means of, for instance, electron-beam welding, plasma-arc welding, laser-beam welding or argon arc-welding to produce a base seam with or without filler material, and thereafter the workpiece flanks forming the narrow gap are united by alternately depositing weld beads at first one and the other workpiece flank by submerged-arc welding

Effect of torch position and angle on welding quality and welding process stability in Pulse on Pulse MIG welding–brazing of aluminum alloy to stainless steel

Abstract: In this paper, Pulse on Pulse metal inert gas (MIG) welding–brazing of 6061 aluminum alloy to 304 stainless steel in a lap configuration was developed to investigate the effect of torch position and angle on the welding quality and welding process stability. Images of arc, electrical signals of welding current, and welding voltage were acquired in synchronous modes by a high-speed camera and electrical signal acquisition system, respectively. The obtained results demonstrate that arc shape, macrostructure, microstructure, and mechanical properties are sensitive to torch aiming position when torch travel angle is 20° and work angle is 0°. However, when travel angle is 20° and work angle is 20°, the effect of torch aiming position is insignificant. It is easier to strike arc and maintain it on the surface of aluminum alloy compared to stainless steel. High-strength joints, whose fracture occurred at heat-affected zones of Al alloys at 89 MPa up to 72 % of the tensile strength of Al alloys, have been obtained. Moreover, a comprehensive evaluation method for the welding process stability based on statistical techniques has been proposed. This method can be easily and quickly integrated in real-time control of the welding process, which provides a quantitative guidance in MIG welding–brazing of aluminum alloy to stainless steel.

Digital Control for an Arc Welding Machine Based on Resonant Converters and Synchronous Rectification

Abstract: This paper presents a field-programmable gate array (FPGA)-based generation of optimized drive signals for resonant converters using synchronous rectification (SR) applied to an arc welding machine. The proposed digital implementation makes the most of the FPGAs capabilities by setting in open loop the arc welding current with enough resolution to establish precisely the operation point, according to the welding technique and metal part requirements. It also optimizes other parameters of interest such as the initial and final welding transient. The resulting system is very flexible because is valid for Tungsten inert gas, shielded metal arc welding, and metal inert gas welding techniques. A novel ad-hoc SR control algorithm for current mode operation that eliminates the dead-times of the power MOSFETs' switching period is proposed. Finally, the experimental results are presented including an efficiency comparison between diodes and SR solutions.