| 摘要 |
A hydrodynamic thrust bearing arrangement (10) (Fig 1) for supporting a rotating machine shaft (12) against axial thrust forces comprises a collar (22) carried by the shaft with axially spaced, axially facing faces (24, 26), one of which, say (24), bears against an array of bearing pads (34L) by way of an intervening lubricant film. The bearing pads may be faced with a polymer or other material which as a poor conductor of heat from the lubricant film which may permit the lubricant to overheat and the film to break down. To avoid this, the collar is made from a metal having a thermal conductivity greater than 150 W m<-1> <o>k<-1> and with such collar thickness to withstand the bending stresses of the axial thrust forces, and the un-loaded face (26) is in contact with a coolant, typically the lubricant, which can transfer heat from the hydrodynamic film even when at ambient temperature. Copper or aluminium alloys may be used, and although require greater thickness than the traditional steel collar for the same lending stiffness, more than compensate by the simplicity of transferring heat out of the collar.
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