Abstract: In order to solve the problems of low welding efficiency and poor quality reliability in ship butt seam welding, this paper carries out research on gas-electric transverse welding technology for ship butt seams. By optimizing the design of key equipment such as water-cooled copper slider and ceramic liner, the gas-electric welding technology is extended to ship construction transverse position butt joints. Subsequently, the key welding parameters such as bevel form, torch position and swing amplitude were reasonably set, and three sets of cross-position butt welding tests with different plate thicknesses were conducted in combination with the structural characteristics of the ship and the requirements of process coverage, and the tensile strength, hardness and impact work of different plate thicknesses were measured to verify the feasibility of the process. The experimental results show that, due to the influence of water-cooled copper slider forced forming on the weld surface and ceramic liner forming at the root of the weld, the resulting weld is beautifully formed, avoiding post-weld grinding and greatly reducing labor intensity; the experimental data of tensile strength, hardness and impact work of each plate thickness meet the requirements of classification society specifications and have a large process margin; the maximum linear energy can reach 93 kJ/cm, welding efficiency can be increased by up to 8 times compared to conventional FCAW cross-welding.Highlights: (1) Optimization of ceramic liner and water-cooled copper slider design, effectively solving the fusion problem of root welds in transverse position butt seam welding of ships.(2) The use of gas-electric transverse welding technology for the welding of transverse posi.The use of gas-electric transverse welding technology for the welding of transverse position butt welds on ships has improved the welding efficiency of transverse position butt welds.