The present disclosure relates to a mechanical assembly of two mechanical parts rotatable relative to each other and enabling a self-centering fluid bearing to be obtained; it comprises a first part provided with a cylindrical cavity, a second part (34) having at least one cylindrical portion engaged in the cylindrical cavity of the first part, a gap separating the cylindrical portion and the wall of the cylindrical cavity so as to allow relative movement in rotation between the first part and the second part (34), and a lubricant distribution network (37, 38) configured for feeding said gap with a fluid lubricant so as to form a fluid bearing; a first surface (34s) selected from the inside surface of the cylindrical cavity of the first part and the outside surface of the cylindrical portion of the second part is provided with at least two lubricant admission orifices (39a, 39b) that are spaced apart from each other by not less than 120° about the main axis (F) of the first surface (34s), and the first surface (34s) also presents at least one circumferential groove (40a) extending circumferentially from the vicinity of a first lubricant admission orifice (39a) over at least 100° and in the direction of rotation of the second of said surfaces relative to the first surface (34s).

A mechanical assembly includes two mechanical parts rotatable relative to each other. A first part is provided with a cylindrical cavity, a second part (34) has at least one cylindrical portion engaged in the cylindrical cavity of the first part, and a gap separates the cylindrical portion and the wall of the cylindrical cavity so as to allow relative movement in rotation between the first part and the second part (34). A lubricant distribution network (37, 38) is configured for feeding the gap with a fluid lubricant so as to form a fluid bearing. A first surface (34s) selected from the inside surface of the cylindrical cavity of the first part and the outside surface of the cylindrical portion of the second part is provided with at least two lubricant admission orifices.