The invention relates to an orbital carrier (2) for a device for butt-welding pipes (C, C) to form a pipeline, said device comprising at least one welding carriage (1) supporting at least one welding head (6) which has at least one welding torch, said orbital carrier (2) surrounding the pipes (C, C) to be welded and being designed to enable positioning and movement in the plane of the joint between the pipes (C, C) of said welding carriage or carriages (1), and said orbital carrier (2) also being movable translationally along the pipeline as it grows. The invention consists in the fact that said orbital carrier (2) consists of at least two components (20) in the form of segments of a circle able to be connected together to form the orbital carrier (2) around the pipes (C, C) during a welding phase and also to allow said orbital carrier (2) to be opened, at least at the top, to allow it to pass an obstruction on the outside of the pipe (C, C). Application: the welding of pipes (C, C).