Patent ID: 8613472

Claim:
A rotary union joint comprising a housing and a bush which is accommodated in sealing relationship in the housing and which has inside surfaces in the form of sliding sealing surfaces for sealing sliding engagement with a rotation machine part, wherein the bush comprises a hollow-cylindrical main body whose inner cylindrical surface forms a sliding sealing surface divided by a peripherally extending inner groove into a first and a second sliding sealing surface and having a cylindrical outside surface which is divided by a peripherally extending outer groove into a first and a second outside surface, wherein a wall portion separating the inner and the outer grooves has at least one bore connecting the two grooves and wherein the first and the second outside surface can be sealed off by a respective stationary sealing ring in relation to a housing embracing the bush, wherein the side surfaces of the inner groove are of the same size within a tolerance threshold of +20% and −35% as the side surfaces of the outer groove and the stationary sealing rings are so positioned on the outside surfaces of the bush in the axial direction that they are at an axial spacing from the axially outer end of the oppositely disposed sliding sealing surfaces, that corresponds to at least 40% and at most 55% of the respective axial length of the sliding sealing surfaces, wherein the bush is configured to withstand pressures of at least 100 bar.