Rotating joint for transferring a first fluid (F 1), comprising: - a male member and a female member mounted so they can be moved in relation to one another; - a mechanical bearing to keep the male and female members concentric; - a sealing ring; - the female member being a substantially cylindrical hollow element whose inner wall has a first annular recess opening around the entire circumference of the inner wall of said female member, said first recess being arranged to receive the seal; - said seal, after being fitted in the first recess, having an upper contact surface and a lower contact surface with said first recess, said contact surfaces being substantially normal to the axis of revolution of the rotating joint and cooperating solely with the first recess; - a second recess coaxial and contained in a plane substantially parallel to and not combined with that of the first recess; - said male and female members being reciprocally arranged to embody a toroidal chamber through which the first fluid flows at a pressure P 1, said first recess being positioned between the toroidal chamber and the second recess; - means for conveying a second pressurised fluid (F 2), at a pressure P 2 higher than that P 1 of the first transferred fluid, to said first recess; said rotating joint being characterised in that it comprises: - means for conveying a third pressurised fluid (F 3) at a pressure P 3 to the second recess; - an additional radial conduit located between the first and second recesses opening into the inner wall of the female member for supplying a fourth fluid (F i) at a pressure P i, such that the pressure P 2 of the second fluid (F 2) is equal to the pressure P 1 of the chamber increased by a strictly positive set pressure differential and the pressure P 3 of the third fluid (F 3) is equal to the pressure P i of the fourth fluid (F i) increased by the same strictly positive set pressure differential. - a male member and a female member mounted so they can be moved in relation to one another; - a mechanical bearing to keep the male and female members concentric; - a sealing ring; - the female member being a substantially cylindrical hollow element whose inner wall has a first annular recess opening around the entire circumference of the inner wall of said female member, said first recess being arranged to receive the seal; - said seal, after being fitted in the first recess, having an upper contact surface and a lower contact surface with said first recess, said contact surfaces being substantially normal to the axis of revolution of the rotating joint and cooperating solely with the first recess; - a second recess coaxial and contained in a plane substantially parallel to and not combined with that of the first recess; - said male and female members being reciprocally arranged to embody a toroidal chamber through which the first fluid flows at a pressure P 1, said first recess being positioned between the toroidal chamber and the second recess; - means for conveying a second pressurised fluid (F 2), at a pressure P 2 higher than that P 1 of the first transferred fluid, to said first recess; - means for conveying a third pressurised fluid (F 3) at a pressure P 3 to the second recess; - an additional radial conduit located between the first and second recesses opening into the inner wall of the female member for supplying a fourth fluid (F i) at a pressure P i, such that the pressure P 2 of the second fluid (F 2) is equal to the pressure P 1 of the chamber increased by a strictly positive set pressure differential and the pressure P 3 of the third fluid (F 3) is equal to the pressure P i of the fourth fluid (F i) increased by the same strictly positive set pressure differential.