Abstract: Machine for friction welding two parts comprising a first non-rotatable means for clamping the first of the two parts and a second rotatable means for clamping the second part. The machine is characterized in that the first non-rotatable clamping means is movable along the axis of rotation of the second means and in that the second rotatable clamping means is made up of a motorized mandril and a headstock clamping between them the second part, this headstock being movable along the axis of rotation and being provided with means for the support of the two pieces co-axially.