Development and Application of Submerged Arc Deep Penetration Welding Technology in Rail Transit Equipment Manufacturing

Through welding process experiments and comparative analysis, the mechanical properties and welding efficiency of double-sided T-joint welding were systematically investigated using a low-carbon high-efficiency submerged arc deep penetration welding technique. The results show that for a 20 mm thick S355J2W(H) weathering steel double-sided T-joint , the double-sided welding can be completed in just 4 passes using the low-carbon high-efficiency welding method in the flat welding position. The welding heat input is only 6.241 kJ/mm, which is 8.96% lower than that of the same method in the PA (flat) position (6.855 kJ/mm) and 37.6% lower than conventional gas-shielded welding (10.014 kJ/mm). The carbon emissions of submerged arc deep penetration welding are 0.666 kg (flat position) and 0.73 kg (PA position), representing reductions of 28.6% (flat position) and 21.8% (PA) compared to conventional gas-shielded welding (0.933 kg). This study also provides data support and guidance for the engineering application of low-carbon high-efficiency submerged arc deep penetration welding to T-joints in different welding positions