Rotating unions are used to convey various media into and through rotating machine parts. Media such as water, hydraulic or thermal oil, pneumatics, vacuum, coolants etc. can be conveyed.

In case of current rotating unions, sealing between the rotating element, “rotor”, and the stationary part, “stator”, is almost always realised by mechanical seals with the respective technical finesses.

Despite extremely precise production and use of highly resistant materials, each rotating union is subject to wear which is inevitable due to its function.
Irrespective of the technical parameters limiting the service life of a rotating union, such as speed, pressure, temperature, flow, volumes and flow velocity of the media, further factors influence the service life considerably.

Accordingly, the mounting process is also a main factor for the service life of a rotating union. Due to their bearing, it is important that it can easily be rotated in mounted condition without any warping. Improper hose length or screwing parts may cause warping of the bearings supplier already at this stage.

In particular the installation of the hoses is very important. The main aspect: First the flexible hoses are to be attached to the rotating union and then it is connected to the shaft end by screwing at the prescribed torque. When connecting the flexible hose to the solid pipe, avoid twisting of the hose. - Never connect the rotating union to a solid pipe. These hoses are to be laid as a bow and without torsion and to be connected to the stationary pipe in a pressure-tight way. ...