Thick-walled X80 pipelines for oil and gas transportation are difficult to relocate due their large size. In the process of narrow-gap overhead welding, welding defects, such as bulges lack sidewall fusion, can appear easily. To avoid these defects improve quality thick-walled pipelines, GMAW method is adopted in this paper. The formation characteristics weld influence arc oscillation parameter...

When the gas metal arc welding (GMAW) process is applied in shipbuilding and heavy equipment industries, it important to increase amount of on weld without defects. Application tandem GMAW can reduce man-hours increased owing multipass productivity. In industry sites, weldments are long large; thus, a carriage-type bed generally used. Accordingly, overall lengths cables system increased; voltag...

The dynamic characteristics of droplet transfer are extremely complicated with the combined effects gravity force and weaving motion during vertical-up welding on thick plate. In this paper, we firstly observed behavior under various parameters high-speed photography electrical signals pulsed gas metal arc (P-GMAW). Then, investigated influences different shape molten pool as well characteristi...

The symmetrical nature in the case of wall fabrication by wire arc additive manufacturing (WAAM) has been observed literature, but it not studied as a source knowledge. This paper focuses on comparative study three drop transfer methods employing Gas Metal Arc Welding (GMAW) technology, one most reported for manufacture aluminum alloys. modes are well-known pulsed GMAW, cold arc, and newer AC. ...

Merchant ships are generally built by joining steels with various welding methods. When the methods used in shipyards examined, it is seen that gas metal arc (GMAW), submerged (SAW), covered electrode and tungsten inert (TIG) come to fore. In assembly of ship hull sheets, GMAW SAW preferred. this sense, extremely important characterize mechanical properties weld zone after shipbuilding steel jo...

In this work, a pulsed welding process has been investigated to highlight how a time varying profile of current impacts on the metal transfer dynamics. First, the process has been recorded using high-speed camera, allowing to qualitatively evaluate the effectiveness of metal transfer and the synchronization of the droplet detachment with current peaks. Second, a timedependent axi-symmetric 2-D ...