Multistage centrifugal compressor

A multistage centrifugal compressor provided with a shaft with a plurality of blades thereon, wherein the shaft is mounted in a housing by bearings, wherein at least one bearing is provided with a bearing damper element comprising a ring arranged between the shaft or the housing and said bearing,

• wherein the ring comprises slots through a thickness of the ring in an axial direction and at a distance from radially-directed inner and outer surfaces of the ring, wherein the slots are at least partially overlapping,
• wherein at least one axial annular surface of the ring is provided with two concentric discs each having a planar surface in contact with the axial annular surface of the ring, an outer one of the two concentric discs having an inner peripheral surface that faces an outer peripheral surface of an inner one of the two concentric discs,
• wherein a viscoelastic material or hysteretic damping material is sandwiched between and in contact with the inner peripheral surface of the outer one of the two concentric discs and the outer peripheral surface of the inner one of the two concentric discs, and
• wherein the viscoelastic material comprises an O-ring or the hysteretic damping material comprises a metal wire mesh.