Rotary union

A rotary union for transferring fluid media from a stationary machine part to a rotating machine part, comprising:

• a stationary housing part for installation in the stationary machine part, wherein the stationary housing part comprises a working space and at least one media inlet channel, opening into the working space, for introducing fluid media into the stationary housing part,
• a rotor for connection to the rotating machine part and having a fluid channel for establishing a fluidic connection to the working space of the stationary housing part,
• a mechanical seal between the stationary housing part and the rotor, wherein the mechanical seal comprises a rotor seal ring that rotates together with the rotor, and an axially movable seal ring assembly having a stator seal ring, and
• an elastomer shape-recovery element which, upon pressurization with a fluid medium, is pressed axially against a wall of the stationary housing part, by a pressure of the fluid medium, and deforms elastically in the process, and wherein the elastomer shape-recovery element resiliently recovers its shape upon depressurization and presses away from the wall by the resilient shape recovery, and in the process pulls the seal ring assembly away from the rotor, in order to open the mechanical seal.