Pipeline girth welding auxiliary tool

The utility model discloses an auxiliary tool for girth welding of a pipeline. The auxiliary tool is formed by detachably connecting two track assemblies with semicircular ring structures, each track assembly comprises two sets of tracks which are arranged and connected in parallel, each set of track is composed of a peripheral arc track, a supporting ring matched with the surface of a circular pipeline and a track supporting piece connecting the arc track and the supporting ring, and the two sets of tracks are connected and fixed through a transverse connecting piece. The two track assemblies of the semicircular ring structures are fixedly connected to the periphery of the circular pipeline through bolt connecting pieces arranged in the circumferential direction of the tracks, and the two sets of tracks are located on the two sides of a welding seam. The auxiliary tool can form a track for a welding tool to run on a circular pipeline, so that the construction efficiency is improved, and the welding quality i