Double-wire tandem GMAW welding process of HSLA50 steel

Increasing the weld deposition rate invariably increases the welding heat input in monofilament arc welding or high efficiency twin wire arc welding and hence cannot be easily optimized to satisfy the needs of special applications requiring high weld deposition. Tri-arc twin wire welding using direct current pulse power supply and variable polarity power supply is proposed. This helps reduce the welding heat input in the work-piece and increase the deposition rate. With increasing the main arc voltage, the droplet transition changed from an unstable mixing transition to a stable repulsion particle transition. In addition, the main arc voltage was increased to 35 V, three arcs could be observed simultaneously. The main arc pulse, when switched on, changed the M arc, arc force, spot force, and plasma flow force. These changes hampered the balance of the original force system and promoted the generation of welding spatter. It may be noted that a sufficient main arc welding voltage can provide appropriate process stability. The third arc provided an additional separation force for the wire droplets and promoted the droplet transfer.

Effect of main arc voltage on arc behavior and droplet transfer in tri-arc twin wire welding

Metal transfer of aluminum alloy double-wire pulsed GMAW with a median waveform

Characteristics of bypass coupling twin-wire indirect arc welding with high-speed welding mode

In order to reduce the influence of polar zone effect in cross-coupling arc by changing inter-wire arc (IWA) configuration, the influence of polarity arrangement of the IWA on droplet transfer was studied. The change of voltage-current waveform and the process of droplet transfer were recorded and analyzed by a high-speed camera and electric signal synchronous acquisition system. The results show that when the IWA polarity is arranged as anode on the bottom and cathode on top, the anode spot force always promotes the droplet transfer and reduces the critical current value of spray transfer. However, with the increase in the input voltage of the IWA, the resistance of the cathode spot force becomes obvious, which hinders the droplet transfer. While the IWA polarity is arranged as anode on top and cathode on the bottom, increasing the input voltage of the IWA obviously reduces the plasma arc voltage. The critical current of spray transfer increases in anode droplet, while the cathode droplet is mainly globular transfer, and there is no spatter explosion process. Through a comprehensive comparison of the droplet transfer process of anode and cathode under the different IWA polarity arrangement, the process of anode and cathode in the IWA polarity arrangement of the anode on top and the cathode on the bottom is more stable than that in the IWA polarity arrangement of the anode on the bottom and the cathode on top, mainly because the cathode spot force under high current do not hinder the cathode droplet.

https://www.mdpi.com/1996-1944/12/23/3985/pdf

J. Wang

Papers

Investigation of arc behaviour and metal transfer in cross arc welding