Abstract: A high-pressure fuel system supplies gaseous fuel to an internal combustion engine. Gaseous fuel pressure within the system is at least 17 MPa during normal operation. The system comprises a number of components and conduits and at least one resilient member for sealing at an interface between two components. The resilient member consists essentially of thermoplastic polyurethane. A corresponding method provides sealing between components containing gaseous fluids at pressures that can be above 17 MPa, in which the gaseous fluids routinely undergo rapid reductions in pressure. The method comprises disposing a resilient member, which consists essentially of thermoplastic polyurethane, at an interface between the components. Gas pressure fluctuations can occur during operation of the components or when the high-pressure gas is vented from the components upon shut down of the high-pressure system.

Abstract: The invention relates to an apparatus and method for supplying high pressure gaseous fuel from a storage vessel to a vehicle's internal combustion engine. More particularly, the invention is a fuel supply system with three main components: the storage vessel; an intensifier; and, an accumulator vessel. Fuel passages connect each one of the components directly with the other two components. The intensifier has a plurality of compression chambers and one of the compression chambers can be by-passed when the intensifier is operating in a low capacity mode, depending upon the pressure in the storage vessel. The intensifier operates continuously. When no fuel compression is required, the intensifier runs in an idle mode with the respective inlets and outlets of the compression chambers connected by fuel passages, thus preventing any fuel compression. The loading to the intensifier actuating mechanism is balanced in all modes of operation.