Welding device for ship piping system

The utility model discloses a welding device for a ship piping system, belongs to the technical field of piping system installation, and aims to solve the problems that two piping systems cannot be quickly butted together by a common piping system butting device, and equipment needs to be debugged again when the piping systems with different sizes are butted. A mounting table is fixedly mounted in the dead center of the table top, a V-shaped groove is formed in the mounting table, a plurality of sets of rolling balls capable of rolling are arranged on the two inclined faces of the V-shaped groove, and a supporting assembly is arranged on the table top. The pipe fittings slide to the bottom of the V-shaped groove along the inclined surface of the V-shaped groove under the action of gravity, the ends of the two pipe fittings are positioned at the same position, so that the centers of circles of the two pipe fittings are the same, the two pipe fittings are aligned, and the two pipe fittings can rotate through a