Abstract: A representative seal system (such as a seal system for a turbopump of a rocket engine) automatically adjusts a balance ratio of a seal. The system can include a ring element encircling an axis. A front side of the ring element contacts a revolving surface to form a seal with the revolving surface. The front side can include a stepped surface having two or more steps. Each step includes a sealing surface configured to contact the revolving surface to form a sealing area that is different from a sealing area of each other sealing surface. Each step is positioned and configured to wear away during operation of the machine to expose an underlying surface to the revolving surface, to change the sealing area and the balance ratio of the seal. A representative method of operating a turbomachinery system includes changing the balance ratio of a seal while rotating a rotor.

Abstract: A representative seal system (such as a seal system for a turbopump of a rocket engine) automatically adjusts a balance ratio of a seal. The system can include a ring element encircling an axis. A front side of the ring element contacts a revolving surface to form a seal with the revolving surface. The front side can include a stepped surface having two or more steps. Each step includes a sealing surface configured to contact the revolving surface to form a sealing area that is different from a sealing area of each other sealing surface. Each step is positioned and configured to wear away during operation of the machine to expose an underlying surface to the revolving surface, to change the sealing area and the balance ratio of the seal. A representative method of operating a turbomachinery system includes changing the balance ratio of a seal while rotating a rotor.

Abstract: An interstage seal for a turbine of a gas turbine engine, the interstage seal having a seal carrier with an axial extending seal tooth movable with a stator of the engine, and a rotor with a seal surface that forms the interstage seal with the seal tooth, where a magnetic force produced by two magnets and a gas force produced by a gas pressure acting on the seal carrier forms a balancing force to maintain a close clearance of the seal without the seal tooth contacting the rotor seal surfaces during engine operation. In other embodiments, two pairs of magnets produce first and second magnetic forces that balance the seal in the engine.

Abstract: A turbine of a gas turbine engine has an air riding seal that forms a seal between a rotor and a stator of the turbine, the air riding seal including an annular piston movable in an axial direction under the influence of a pressure on one side with a pressure acting on an opposite side that self-balances the air riding seal during the steady state condition of the engine and lifts off the seal during engine transients.

Abstract: An air riding seal for a turbine in a gas turbine engine, where an annular piston is axial moveable within an annular piston chamber formed in a stator of the turbine and forms a seal with a surface on the rotor using pressurized air that forms a cushion in a pocket of the annular piston. A purge cavity is formed on the annular piston and is connected to a purge hole that extends through the annular piston to a lower pressure region around the annular piston or through the rotor to an opposite side. The annular piston is sealed also with inner and outer seals that can be a labyrinth seal to form an additional seal than the cushion of air in the pocket to prevent the face of the air riding seal from overheating.

Abstract: An air riding seal between a rotor and a stator in a turbine of a gas turbine engine, where an annular piston is movable in an axial direction within a housing that extends from the stator, and a bellows is secured to the annular piston to form a flexible air passageway from a compressed air inlet through the annular piston and into a cushion cavity that forms an air riding seal between the annular piston and the rotor sealing surface. In another embodiment, a flexible seal secured to and extending from the annular piston forms a sealing surface between the annular piston chamber and the annular piston to provide a seal and allow for axial movement.

Abstract: A floating air riding seal for a gas turbine engine with a rotor and a stator, an annular piston chamber with an axial moveable annular piston assembly within the annular piston chamber, an annular cavity formed on the annular piston assembly that faces a seal surface on the rotor, and a central passage connecting the annular cavity to the annular piston chamber to supply compressed air to the seal face, where the annular piston assembly is a split piston assembly to maintain a tight seal as coning of the rotor disk occurs.

Abstract: A gravity drained bearing compartment with two oil shields that are located near to an air vent and an oil scavenge line, where the oil shields function to reduce circumferential momentum of the oil to prevent oil from entering the air vent and direct oil into the scavenge line.

Abstract: A loose terrain traction assist device for wheeled vehicles includes a generally frusto-conical structure having a proximal portion with a diameter smaller than an overall diameter of a tire of a vehicle, a distal portion that extends outwardly from the wheel, and an outer surface defined between the proximal portion and the distal portion. The traction assist device also includes an attachment arrangement for releasably coupling the frusto-conical structure to a wheel assembly of the vehicle, such that at least part of the frusto-conical structure is adapted to engage with terrain during operation of the vehicle in loose terrain and to not engage with terrain during operation of the vehicle on normal terrain.

Abstract: A loose terrain traction assist device for wheeled vehicles includes a generally frusto-conical structure having a proximal portion with a diameter smaller than an overall diameter of a tire of a vehicle, a distal portion that extends outwardly from the wheel, and an outer surface defined between the proximal portion and the distal portion. The traction assist device also includes an attachment arrangement for releasably coupling the frusto-conical structure to a wheel assembly of the vehicle, such that at least part of the frusto-conical structure is adapted to engage with terrain during operation of the vehicle in loose terrain and to not engage with terrain during operation of the vehicle on normal terrain.

Abstract: A loose terrain traction assist device for wheeled vehicles includes a generally frusto-conical structure having a proximal portion with a diameter smaller than an overall diameter of a tire of a vehicle, a distal portion that extends outwardly from the wheel, and an outer surface defined between the proximal portion and the distal portion. The traction assist device also includes an attachment arrangement for releasably coupling the frusto-conical structure to a wheel assembly of the vehicle, such that at least part of the frusto-conical structure is adapted to engage with terrain during operation of the vehicle in loose terrain and to not engage with terrain during operation of the vehicle on normal terrain.

Abstract: In one embodiment, the present invention is a loose terrain traction assist device for wheeled vehicles, comprising a generally frusto-conical structure having a proximal portion with a diameter smaller than an overall diameter of a tire of a vehicle, a distal portion that extends outwardly from the wheel, and an outer surface defined between the proximal portion and the distal portion. The traction assist device also includes an attachment means for releasably coupling the frusto-conical structure to a wheel assembly of the vehicle, such that at least part of the frusto-conical structure is adapted to engage with terrain during operation of the vehicle in loose terrain and to not engage with terrain during operation of the vehicle on normal terrain.