Equalizing valve (1) comprising a duct (6) having an inlet section (7) and an outlet section (8), a seat (10) and a valve element (12) able to move between a closed position and an open position, characterized in that said duct is able to admit a flow in which, for any flow line (13) between said inlet section and said outlet section, the velocity vector (15) at a given point makes an angle with the velocity vector (14) in the inlet section which increases with the distance away from the inlet section, the angle between the velocity vector (16) in the outlet section and the velocity vector in the inlet section ranging between 80° and 150°, and in which the valve element, in the closed position, makes an angle of between 0° and 70° with the normal to the outlet section.