A tilting pad thrust bearing arrangement (10, FIG. 1(b)) consists of an annular backing ring (12) providing an axially facing supporting surface (11) on which an array of bearing pads (20.sub.1, 20.sub.2 . . . 20.sub.i) is carried. Each pad has a flat supported surface (22.sub.1) clamped to a thin mounting ring (30) of resilient steel by a headed fastener (41.sub.i) which bears on the supporting surface. The mounting ring is supported clear of the supporting surface at mounting points (32.sub.i) each side of each bearing pad which define a stand-off distance between ring and supporting surface of less than the height of each fastener head so that the ring is biased and each pad is lifted at the clamping position with its edges clear of the ring, thereby permitting it to pivot about the fulcrum formed by the fastener head. The supporting surface may be an intervening resilient ring (FIGS. 5 and 6).

A pod propulsion system comprises a housing defining a fluid duct and an annular drum rotatably mounted to the housing within the fluid duct. The annular drum has a drum interior and a cylindrical outer surface. The system further comprises a rotor mounted to the drum for rotation therewith, the rotor and the drum having a common axis of rotation. A bearing assembly mounted to the housing comprises a first bearing comprising a first plurality of bearing pads disposed circumferentially around the drum. Each pad has a pad bearing surface adapted to contact a first drum portion in a predetermined manner and is pivotably mounted to the housing so as to maintain contact of the pad bearing surface with the first drum portion in the predetermined manner when an orientation of the drum portion relative to the housing changes.

A bearing that can be reoriented to move its center is disclosed. The center of the bearing is offset from the center of its outer housing. Should the shaft extending through the bearing need to be raised or lowered the outer housing is simply rotated in its receptacle and its position is fixed. Reconfiguring the bearing receptacle or using shims is eliminated and the alignment process is rendered shorter and more reliable future operation is obtained.

A bearing configuration for use in electrical submersible pumps having improved stability. The bearing configurations include multi-lobed bearings, such as lemon bore, tri-lobe bearings, pocket bearings and tilting pad type bearings.

Disclosed is a radial tilt pad bearing assembly comprising: an outer carrier; a plurality of tilt pads retained within the outer carrier; and a corresponding plurality of retaining pins to retain the tilt pads in given circumferential positions, each fixed in the bearing assembly outer carrier so as to abut a side face of a cavity in the corresponding tilt pad. At least one retaining pin and the corresponding cavity are respectively shaped such that, when in use, a clearance in a plane transverse to the axes of the bearing assembly and the tilt pad between the retaining pin and the side face is lesser at a first location which lies substantially at the inner surface of the carrier, than at all corresponding locations at radially inner portions of the side face, with respect to the first location. A contact point between the retaining pin and the tilt pad when in use, lies substantially at the inner surface of the outer carrier. The tilt pad is accordingly able to tilt without being substantially displaced circumferentially about the outer carrier. Further disclosed is a retaining pin for use in such a bearing system.