Abstract: A reciprocating cryogenic pump 2 comprises a piston reciprocable within a pumping chamber 44. The pumping chamber 44 has an inlet suction valve 48 for cryogenic liquid to be pumped and an outlet 32 for high pressure cryogenic liquid. The inlet valve 48 for the cryogenic liquid communicates with a cryogenic liquid reception chamber 46 in the cold end or head 6 of the pump 2. The pump head 6 is at least partially surrounded by a first jacket 8 retaining primary vacuum insulation. The first jacket 8 is itself at least partly surrounded by a second jacket 10. The jacket 10 defines a chamber for the reception of a coolant fluid such as liquid nitrogen and the second jacket has an inlet 20 and an outlet 22 for the liquid nitrogen. The thermal insulation can be further enhanced by a trapped gas space 73 between the first jacket 8 and an inner sleeve 52, the latter defining with an outer sleeve 50 vacuum insulation for the pumping chamber 44.

Abstract: A cryogenic pump has an associated heater for vaporizing cryogenic fluid. The heater has a chamber (bounded by an inner sleeve and an outer sleeve) disposed around at least a portion of the pump housing. The heater has a helical heating coil with a plurality of turns disposed within the chamber and a helical baffle having a plurality of turns interspaced with the turns of the heating coil for guiding heat exchange fluid over the turns of the heat exchange coil. The heater has an inlet for cryogenic fluid to communicate with the heat exchange coil and an outlet for the resulting vaporized fluid. Heat exchange fluid flows through an inlet of the heater chamber to an outlet of the heater chamber and then through a space defined between the inner sleeve and a portion of the pump housing.

Abstract: A reciprocating cryogenic pump 2 comprises a piston reciprocable within a pumping chamber 44. The pumping chamber 44 has an inlet suction valve 48 for cryogenic liquid to be pumped and an outlet 32 for high pressure cryogenic liquid. The inlet valve 48 for the cryogenic liquid communicates with a cryogenic liquid reception chamber 46 in the cold end or head 6 of the pump 2. The pump head 6 is at least partially surrounded by a first jacket 8 retaining primary vacuum insulation. The first jacket 8 is itself at least partly surrounded by a second jacket 10. The jacket 10 defines a chamber for the reception of a coolant fluid such as liquid nitrogen and the second jacket has an inlet 20 and an outlet 22 for the liquid nitrogen. The thermal insulation can be further enhanced by a trapped gas space 73 between the first jacket 8 and an inner sleeve 52, the latter defining with an outer sleeve 50 vacuum insulation for the pumping chamber 44.

Abstract: A cryogenic pump is typically used to supply high pressure natural gas to an engine. The pump has a piston operable to discharge cryogenic liquid from a pumping chamber within a pump housing. The cryogenic liquid exits the chamber through an outlet port in which a check valve is positioned. The check valve has a valve member which is loaded by a spring and is retained by a retaining member accessible from outside the housing. The check valve has an inlet which is axial with the valve member and an outlet which is transverse to the axis of the valve member.

Abstract: A cryogenic pump for a cryogenic liquid has associated therewith a heater for vaporizing the cryogenic liquid. The heater comprises a chamber (bounded by an inner sleeve and an outer sleeve), a helical heating coil having a plurality of turns disposed within the chamber, an inlet for cryogenic liquid communicating with the heat exchange coil and an outlet for resulting heated fluid communicating with the heat exchange coil. An inlet and an outlet from the water chamber for heat exchange fluid are provided. The heater chamber has a helical baffle having a plurality of turns for guiding the heat exchange fluid over the turns of the heat exchange coil. The turns of the baffle are interspaced with the turns of coil.