A flange for a pump comprises first and second faces and a passageway for cryogenic fluid flow extending from the first face to the second face and at least one of (1) the passageway is for a pipe and comprises a first portion of a first diameter and a second portion of a second diameter greater than the first diameter, wherein when the pipe has an outer diameter that is smaller than the second diameter a gap is formed between the pipe and the passageway where the pipe passes through the second portion; and (2) a first annular groove in one of the first face and the second face and extending around the passageway, wherein the first annular groove in cooperation with the passageway forms a bellows. The gap and bellows increase the thermal resistance between the passageway and the flange, and the bellows allows for flexure during thermal contractions of the flange reducing thermal stress on welded fluid seals.

There is provided a cryopump including a cryocooler, a cryopanel that is cooled by the cryocooler, a cryopump container that includes a container body, which accommodates the cryopanel, and a cryocooler accommodating tube of which one end is coupled to the container body and the other end is fixed to the cryocooler and into which the cryocooler is inserted, a vent valve for exhausting a fluid from the cryopump container, a first exhaust passage that includes a first exhaust port provided in the container body, is disposed outside the cryopump container, and connects the first exhaust port to the vent valve, and a second exhaust passage that includes a second exhaust port provided in the cryocooler accommodating tube, connects the second exhaust port to the vent valve, and merges with the first exhaust passage between the first exhaust port and the vent valve.

A vacuum pumping system comprising: a high pressure getter pump configured to operate from an initial pressure of between 10 and 10.sup.−2 mbar to a second pressure between 10.sup.−3 mbar and 10.sup.−6 mbar and at least one high vacuum pump configured to operate at higher vacuums than the high pressure getter pump, the two pumps being mounted on a same flange, the flange being configured to mount the vacuum pumping system to a vacuum chamber.

There is provided a cryopump including a cryocooler, a cryopanel that is cooled by the cryocooler, a cryopump container that includes a container body, which accommodates the cryopanel, and a cryocooler accommodating tube of which one end is coupled to the container body and the other end is fixed to the cryocooler and into which the cryocooler is inserted, a vent valve for exhausting a fluid from the cryopump container, a first exhaust passage that includes a first exhaust port provided in the container body, is disposed outside the cryopump container, and connects the first exhaust port to the vent valve, and a second exhaust passage that includes a second exhaust port provided in the cryocooler accommodating tube, connects the second exhaust port to the vent valve, and merges with the first exhaust passage between the first exhaust port and the vent valve.

A cryopump system includes a plurality of cryopumps, each cryopump including a rough valve connecting the cryopump to a common rough pump and a pressure sensor measuring a pressure in the cryopump, and a controller that controls, for each cryopump, the rough valve based on a measured pressure from the pressure sensor such that the cryopump is decompressed to a first reference pressure by the common rough pump and thereafter a vacuum is maintained in the cryopump, and the cryopump is further decompressed to a second reference pressure lower than the first reference pressure by the common rough pump. The controller is configured to, based on the measured pressure from the pressure sensor of a first cryopump, open the rough valve of a second cryopump such that the second cryopump is decompressed to the first reference pressure while the vacuum is maintained in the first cryopump.

A cryopump system includes a plurality of cryopumps, each cryopump including a rough valve connecting the cryopump to a common rough pump and a pressure sensor measuring a pressure in the cryopump, and a controller that controls, for each cryopump, the rough valve based on a measured pressure from the pressure sensor such that the cryopump is decompressed to a first reference pressure by the common rough pump and thereafter a vacuum is maintained in the cryopump, and the cryopump is further decompressed to a second reference pressure lower than the first reference pressure by the common rough pump. The controller is configured to, based on the measured pressure from the pressure sensor of a first cryopump, open the rough valve of a second cryopump such that the second cryopump is decompressed to the first reference pressure while the vacuum is maintained in the first cryopump.

A cryopump comprises a refrigerator, a condensing array cooled by the refrigerator, a radiation shield surrounding the condensing array and cooled by the refrigerator. The radiation shield has a frontal opening covered by a frontal array that is also cooled by the refrigerator. The frontal array comprises louvers across an otherwise substantially open center region of the frontal opening and an orifice plate across an outer region of the frontal opening. The hybrid frontal array allows for pumping speeds approximating those of a louver frontal array but with flow control comparable to an orifice plate.

A flange for a pump comprises first and second faces and a passageway for cryogenic fluid flow extending from the first face to the second face and at least one of (1) the passageway is for a pipe and comprises a first portion of a first diameter and a second portion of a second diameter greater than the first diameter, wherein when the pipe has an outer diameter that is smaller than the second diameter a gap is formed between the pipe and the passageway where the pipe passes through the second portion; and (2) a first annular groove in one of the first face and the second face and extending around the passageway, wherein the first annular groove in cooperation with the passageway forms a bellows. The gap and bellows increase the thermal resistance between the passageway and the flange, and the bellows allows for flexure during thermal contractions of the flange reducing thermal stress on welded fluid seals.

A cryogenic pump system includes a supply of liquid natural gas, a source of hydraulic fluid, a cryogenic pump, and an electronic control module. The cryogenic pump is operatively arranged with the supply of liquid natural gas and the source of hydraulic fluid. The cryogenic pump is configured to operate using the source of hydraulic fluid to compress at least some of the supply of liquid natural gas for delivery to an engine. The electronic control module is operably arranged with the cryogenic pump and configured to selectively operate the cryogenic pump. Control strategies for operating the cryogenic pump system are disclosed which have reduced power demands.

A drive system for a cryogenic pump is provided including a spool housing having a plurality of valves disposed therein about a pump axis and a tappet housing including a plurality of tappet bores, each tappet bore in communication with a respective one of the plurality of valves. A collection cavity collects hydraulic fluid from the tappet bores. A pump flange includes a fluid inlet and a fluid outlet. An inlet manifold directs hydraulic fluid received through the fluid inlet to each of the plurality of valves. An outlet manifold directs hydraulic fluid from each of the valves and the collection cavity to the fluid outlet.