Abstract: The shaft seal arrangement for a rotating turbomachine shaft having a rotation axis, comprises a rotor part and a stationary part. A dry gas seal is further provided, in combination with a cooling fluid volume arranged for receiving a cooling fluid and in heat exchange relationship with the dry gas seal. A venting arrangement collectively vents exhaust cooling fluid and dry sealing gas from the shaft seal arrangement.

Abstract: The shaft seal arrangement for a rotating turbomachine shaft having a rotation axis, comprises a rotor part and a stationary part. A dry gas seal is further provided, in combination with a cooling fluid volume arranged for receiving a cooling fluid and in heat exchange relationship with the dry gas seal. A venting arrangement collectively vents exhaust cooling fluid and dry sealing gas from the shaft seal arrangement.

Abstract: A method for operating a rotating machinery comprising a rotor, a rotor shaft, and at least one journal bearing supporting the rotor shaft is disclosed. The bearing comprises a bearing housing, a bearing surface in the bearing housing, a sleeve torsionally and axially fitted on the shaft, and a lubrication oil film filling a clearance between the outer surface of the sleeve and the bearing surface. The method comprises the step of modifying the clearance by modifying a radial dimension of the outer surface of the sleeve as a function of a rotation speed of the shaft.

Abstract: A method for operating a rotating machinery comprising a rotor, a rotor shaft, and at least one journal bearing supporting the rotor shaft is disclosed. The bearing comprises a bearing housing, a bearing surface in the bearing housing, a sleeve torsionally and axially fitted on the shaft, and a lubrication oil film filling a clearance between the outer surface of the sleeve and the bearing surface. The method comprises the step of modifying the clearance by modifying a radial dimension of the outer surface of the sleeve as a function of a rotation speed of the shaft.

Abstract: Disk wheel (10) of a rotor of a turbomachine of the type equipped with a series of blades (12) integral with a central annular portion (14) which is fitted on a shaft (20) of the turbomachine, the disk wheel comprises at least a first insertable portion (18) of the female or male type situated close to a base end of the central annular portion (14), which is suitable for being coupled with at least a corresponding second insertable portion (38) of the male or female type integral with the shaft (20) so as to increase the reliability of the disk wheel (10) itself.

Abstract: A labyrinth seal is disclosed having a stator, a plurality of teeth extending from the stator, each teeth having an end portion, and a rotor having an outside surface disposed next to the end portions of the plurality of teeth of the stator. The rotor further includes a plurality of grooves on the outside surface thereof, each groove is disposed between adjacent teeth of the stator, and a cavity formed between adjacent teeth and the each groove is configured to induce a vortex motion to a leakage flow from the high-pressure side to the low-pressure side of the seal so as to reduce a flow rate of the leakage flow. Methods of reducing a leakage flow in labyrinth seal are also disclosed.