Abstract: The present invention provides apparatus and methods for balancing stacked components of rotating machinery, such as in a gas turbine engine. Unlike conventional processes and devices for balancing stacked components, the present invention may use a single non-parallel spacer for obtaining an acceptable and repeatable component group balance. The non-parallel spacer may be used to compensate for rotor bow and the associated imbalance of the rotor group. By indexing a spacer with non-parallel faces, situated terminally at the end of the stack adjacent to the nut, rotor balance can be achieved without disassembly of the rotor group and clocking of its individual components. A spacer may also be disposed at any one or more of the interfaces between various components in the stack.

Abstract: A shaft oil purge system comprises an entrance seal, an exit seal and a buffer air flow. The entrance seal comprises a circumferential carbon seal running on an inner shaft and another carbon seal running on an outer shaft. The exit seal comprises a labyrinth seal positioned on the inner shaft and towards the exit end of the annulus between the shafts. An abradable material filled groove positioned radially outward from the exit seal allows the inner shaft to rub without compromising the integrity of the outer shaft. The buffer air flow enters the annulus from a cavity at the entrance seal, purges oil from the annulus and improves the efficiency of the seals.

Abstract: A support for a bearing comprises a resilient ring having unevenly spaced inner and outer bumpers. The unevenly spaced bumpers provide anisotropy to the rotor to preclude non-synchronous vibration. The inner bumpers can be ground to provide a vertical offset of the rotor centerline to accommodate the deflection due to the rotor weight. A tangential groove in the outer bumper allows oil passage during ring deflection so that oil can be squeezed out under dynamic load, providing additional viscous damping to the rotor.

Abstract: The present invention provides a centering feature to the bearing assembly of a turbomachine to provide optimum operating characteristics of the squeeze film damper. Unlike conventional bearing centering methods and apparatus, a compact compliant centering support for the squeeze film damper interfaces between a bearing outer race, and an outer support structure. The compact design is lightweight and inexpensive, can be retrofitted easily to an existing turbomachine, such as a turbine and compressor, for improved rotor dynamic performance. The compact compliant centering support damper may be comprised of a ring with bumpers spaced around the circumference at the inside and outside diameters to form spring elements between the bumpers. The centering support may lift the rotor inside the squeeze film cavity and may eliminate rotor weight effect on the damper performance.

Abstract: An apparatus and method that provides a flexible anisotropic support, which may accommodate open, closed, or re-circulating squeeze film damper in parallel, has improved internal rolling element clearances, limits maneuver and blade loss responses by limiting rotor excursion, and has a rotor centering feature. This is accomplished through the combination of beam and ring arrangement, which provides support anisotropy that produces beneficial cross-coupling stiffness for the support to control synchronous and non-synchronous vibration.

Abstract: An apparatus and method that provides a flexible anisotropic support, which may accommodate open, closed, or re-circulating squeeze film damper in parallel, has improved internal rolling element clearances, limits maneuver and blade loss responses by limiting rotor excursion, and has a rotor centering feature. This is accomplished through the combination of beam and ring arrangement, which provides support anisotropy that produces beneficial cross-coupling stiffness for the support to control synchronous and non-synchronous vibration.