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: 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.