Abstract: A medium and high pressure pump systems supplies a cryogenic fluid from a storage tank. The system comprises a pump that is operable to pump cryogenic liquid or a mixture of cryogenic liquid and vapor. The pump preferably comprises an inducer with at least two chambers and means for recycling excess fluid within the inducer instead of returning excess fluid to the storage tank. The reciprocating pump is preferably double acting such that fluid is discharged from the pump during both extension and retraction strokes.

Abstract: A medium and high pressure pump systems supplies a cryogenic fluid from a storage tank. The system comprises a pump that is operable to pump cryogenic liquid or a mixture of cryogenic liquid and vapor. The pump preferably comprises an inducer with at least two chambers and means for recycling excess fluid within the inducer instead of returning excess fluid to the storage tank. The reciprocating pump is preferably double acting such that fluid is discharged from the pump during both extension and retraction strokes.

Abstract: A method and apparatus is provided for supplying both cryogenic liquid and vapor from a storage tank to a pump to reduce the need for venting. The pump is operable to pump cryogenic liquid or a mixture of liquid and vapor. Different operating modes are selectable to control mass flow rate through the pump. With one operating mode a high flow rate is achieved by supplying only cryogenic liquid to the pump. By selecting another operating mode, a lower mass flow rate is achieved by simultaneously supplying liquid and vapor from the storage tank to the pump. The pump preferably has an inducer with at least two chambers and valves for recycling excess fluid within the inducer instead of returning it to the storage tank. The reciprocating pump is preferably double acting such that fluid is discharged from the pump during both extension and retraction strokes.

Abstract: A medium and high pressure pump systems supplies a cryogenic fluid from a storage tank and methods of operating such systems to remove both liquid and vapor from the storage tank to reduce the need for venting. The system comprises a pump that is operable to pump cryogenic liquid or a mixture of cryogenic liquid and vapor. In accordance with the method, mass flow rate through the pump is controlled by selecting one of at least two operating modes. In a first operating mode a high flow rate is achieved by supplying cryogenic liquid to the pump from the storage tank to substantially fill a compression chamber within the pump with liquid. In a second operating mode, a lower mass flow rate is achieved by selectively simultaneously supplying liquid and vapor from the storage tank to the pump, with the vapor fraction being higher in the second operating mode compared to the first operating mode.

Abstract: This invention relates to a medium and high pressure liquid natural gas fuel system for internal combustion engines and for other cryogenic systems.

Abstract: The invention relates to an apparatus and method for supplying high pressure gaseous fuel from a storage vessel to an internal combustion engine of a vehicle, or for other uses.