Abstract: An apparatus for liquefying and storing a gas is provided. The apparatus is adapted to liquify relatively small quantities of gas, and to do so in a residence or place of business. The apparatus generally includes a cryocooler, a heat transfer assembly, and an insulated subsystem. Liquid condensate produced by the apparatus is stored in an insulated dewar. The method of the present invention includes the liquification of air or an enriched gas on a small scale in a residence or place of business. The method and apparatus of the invention are particularly well suited for providing liquified oxygen for use by a patient on oxygen therapy in the patient's residence.

Abstract: An improved helical dry screw expander particularly suited for cryogenic service and its use in a cryogenic rectification system. The improved helical dry screw expander is particularly advantageous in a cryogenic waste expansion cycle particularly for nitrogen production.

Abstract: An improved helical dry screw expander particularly suited for cryogenic service and its use in a cryogenic rectification system. The improved helical dry screw expander is particularly advantageous in a cryogenic waste expansion cycle particularly for nitrogen production.

Abstract: Turbomachine and method of operation wherein shroud seal fluid is channelled from the turbomachine at or proximate to the seal and preferably recycled back to the turbomachine.

Abstract: A method and apparatus for work expanding a cryogenic liquid wherein the liquid is expanded in a manner to avoid a transient pressure drop below the flash point thus reducing the potential for cavitation and consequent operating inefficiencies.

Abstract: A bearing support system providing axial thrust load control of bearing supporting a rotating element, by retaining the bearings with a slotted inner ring and supporting the inner ring with a radially spaced outer ring by means of a plurality of circumferentially spaced supports which are radially stiff but axially flexible.

Abstract: A process to produce liquid cryogen wherein subcooled supercritical liquid is expanded without vaporization and a portion thereof is used to carry out the subcooling by vaporization under reduced pressure.

Abstract: A bearing system for high-speed rotary machinery wherein shaft support, flexible support and viscous damping are provided by separate and distinct mechanisms each of which can be adjusted independently of the other two.

Abstract: A system for enhancing the performance of the external condensing surfaces of the vertical tubes of a film condensation heat exchanger comprising a network of enhancement elements adjacent the tube surface to collect the condensate into rivulets and connecting elements wrapped around and bonded to the enhancement elements to maintain the latter in their proper positions. In a preferred embodiment, both the enhancement and connecting elements are made of a wettable plastic polymeric material in the form of a sleeve to slip over the condenser tube as a prefabricated unit.

Abstract: A method of forming an isostress-contoured die from a metal workpiece by discreet, sequential machining steps. A plurality of spaced-apart truncated conoidal projections, arranged in repetitive diamond-shaped patterns, are formed from the workpiece. Depressions are machined in the workpiece portions associated with each diamond pattern and the ridges between adjacent depressions are reduced by machining to form isostress-contoured surface portions between and surrounding the projections.

Abstract: A heat exchanger assembly comprising a stacked array of thin-walled heat exchange channel elements, having first fluid entrance and exit faces at opposite ends of the array. The improved headering arrangement includes a resilient gasket disposed around the perimeter of each face against the wall portion ends thereof and header tank means enclosing each face of the array, arranged to bear compressively against the resilient gasket and form a fluid-tight seal between the header tank and the stacked array.

Abstract: A boiling surface layer is formed on a thermally conductive wall comprising a plurality of ridges separated by grooves provided at microscopic density, with outer sections of the ridges partly deformed into adjacent grooves to provide sub-surface cavities with restricted openings to the outer surface and sub-surface, openings between some of the cavities.