Pipeline welding robot and welding method thereof

The invention relates to pipeline welding and provides a pipeline welding robot and a welding method thereof.The pipeline welding robot comprises a driving device, an angle measuring device connected with the driving device and a welding device connected with the driving device; the driving device is arranged on the outer wall of the pipeline and does circular motion around the pipeline; the angle measuring device is used for measuring an included angle between a connecting line between adjacent welding spots on the outer walls of adjacent pipelines and a pipeline axis; the welding device comprises an electric welding head and a rotating device; the rotating device drives the electric welding head to deflect with the outer wall of the end of the pipeline as the circle center according to angle data measured by the angle measuring device. According to the pipeline welding robot and the welding method thereof, the corresponding welding angle can be adjusted according to different alignment degrees of pipelines,