Abstract: A turbomachine includes a shaft with a first end and an impeller arranged at and coupled to the first end of the shaft, arranged together to rotate about an axis of rotation. The turbomachine further includes a friction ring clamped between an axial surface at the first end of the shaft and an opposite axial surface of the impeller.

Abstract: Multistage centrifugal compressor provided with a shaft with blades, which is mounted in a housing with bearings. At least one bearing is provided with a bearing damper element including a ring arranged between the shaft and the bearing. The ring includes slots through the thickness of the ring in the axial direction (X-X?) and at a distance from the radially-directed inner and outer surface of the ring. The slots are at least partially overlapping, and: A) the slots are filled with a liquid, and the axial annular surfaces are closed off by means of a protective cap; or: B) at least one of the annular surfaces is provided with a viscoelastic material or hysteretic damping material sandwiched between two concentric discs, which discs are attached to the ring; or: C) the slots are filled with a viscoelastic material.

Abstract: Gear wheel that is provided with spokes (17) which extend between a rim (16) supporting a gear mesh (15) and a corresponding gear hub (18), whereby free spaces (19) are located between the spokes (17) which extend between the rim (16) and the gear hub (18), characterised in that at least one of said free spaces (19) is filled with a block (20) made of a rigid, incompressible material, whereby between the gear wheel (10) on the one hand and the block (20) on the other hand a viscoelastic material (21) is located.

Abstract: A device includes a bearing-in-bearing with an inner ring, an intermediate ring and an outer ring. Between the inner ring and the intermediate ring and between the intermediate ring and the outer ring, inner roller elements, and outer roller elements, are attached, respectively. The bearing-in-bearing is attached between two components that can rotate in relation to each other, a shaft and a housing, of which one component is or can be connected to a drive. A transmission is provided between the intermediate ring and the driven component in order to drive the intermediate ring. The transmission is a contactless transmission.

Abstract: A bearing damper element includes a ring mounted between a rotating object and a supporting object which supports the ring. The ring includes at least three slits through the thickness of the ring in the axial direction and at a distance of the radial inner and outer surface of the ring. At least half of the slits have one or more damping parts with a maximum width of 0.5 millimeters, whereby the damping parts are concentric and do not overlap.

Abstract: A device includes a bearing-in-bearing with an inner ring, an intermediate ring and an outer ring. Between the inner ring and the intermediate ring and between the intermediate ring and the outer ring, inner roller elements, and outer roller elements, are attached, respectively. The bearing-in-bearing is attached between two components that can rotate in relation to each other, a shaft and a housing, of which one component is or can be connected to a drive. A transmission is provided between the intermediate ring and the driven component in order to drive the intermediate ring. The transmission is a contactless transmission.

Abstract: A bearing damper element includes a ring mounted between a rotating object and a supporting object which supports the ring. The ring includes at least three slits through the thickness of the ring in the axial direction and at a distance of the radial inner and outer surface of the ring. At least half of the slits have one or more damping parts with a maximum width of 0.5 millimeters, whereby the damping parts are concentric and do not overlap.