Multipass Narrow Gap of Heavy Gauge Steel with Filler Wire

In situ tensile of ultra-narrow gap laser welded joint of bainitic steel

“…The joint was welded by bottom laser self-melting and laser wire filling (Figure 1), and the key welding parameters are shown in Table 1. A standard tensile test is unable to accurately characterise the local mechanical properties of welded joints because of the complex micro-structure and varying properties of local micro-zones [12,13]. To reveal the fracture characteristics of different micro-zones in a joint, micro-tensile samples were made from different micro-zones of joints for in situ tensile observation under SEM (scanning electron microscopy).…”

Narrow Gap Welding of X80 Steel Using Laser-CMT Hybrid Welding with Misaligned Laser and Arc

“…However, the method requires the use of plates that are manufactured with high precision. Laser-arc hybrid welding [16][17][18][19][20] integrates the advantages of both laser and arc. Compared with arc welding, the phenomenon that the arc may climb upward to the sidewall of groove can be restricted by the laser, i.e., the stiffness of the arc can be improved by the laser [16].…”

Multi-Pass Laser and Hybrid Laser-Arc Narrow-Gap Welding of Steel Butt Joints

“…Gas-metal-arc welding [1,7,8,16,17,19], submerged arc welding [5,9,16,17,19,20], electron beam welding [5,7,16] and electroslag welding [19] received wide acceptance for the fabrication of steel structures from carbon steel plates 10-50 mm thick to manufacture sea ships [1, 6, 7, 14, ], large-size vessels [1, 3, 5-7, 9, 14, 16] and oil and gas pipelines [1,6,7,14,16]. However, besides certain technological advantages [5,16,20], these welding methods also have a number of drawbacks, such as large size of the weld and HAZ [1,7,16,19], susceptibility to hot cracking [1,16,19], necessity for postweld heat treatment (tempering) [7,16,19], presence of high residual thermal strains [1,7,19]. The low productivity of these processes is also explained by the need for preliminary edge beveling at an angle of 30° and more [1,7,16,19].…”

“…However, besides certain technological advantages [5,16,20], these welding methods also have a number of drawbacks, such as large size of the weld and HAZ [1,7,16,19], susceptibility to hot cracking [1,16,19], necessity for postweld heat treatment (tempering) [7,16,19], presence of high residual thermal strains [1,7,19]. The low productivity of these processes is also explained by the need for preliminary edge beveling at an angle of 30° and more [1,7,16,19].…”

“…The technologies for automated multi-pass consumable-electrode narrow-gap arc welding of steels up to 100 mm thick [1,7,16,[19][20][21] are known. The distinctive feature of the technologies is that the weld edges beveled at an angle of 1.0-1.5° are made with a gap of 10-18 mm on a backing, the welding torch is introduced into the gap, and then the gap is filled with a molten filler wire 1.6 or 2-3 mm in diameter at reciprocating movement of the torch.…”