A device and a method for assembling oriented objects, such as parts of a pipeline. The device includes means for rotational displacement about a rotational axis of a first and second base. The first base has a first main axis which is perpendicular to the rotational axis and includes first means for supporting objects that can be displaced in translation along the first main axis. The second base has a second main axis which is perpendicular to the rotational axis and includes second means for supporting objects and a revolving plate device for supporting and orienting one of the objects in an angular manner. The revolving plate device can be displaced in translation in relation to the second supporting means along the second main axis. Visualization means enable at least the rotational angle of the plate and the position of the second base to be visualised.