Abstract: A wire-drawing optical fiber base material manufacturing method of heating an optical fiber base material by a heater and forming a drawing shape portion at an end portion. The manufacturing method includes: forming, by a flow-regulating member disposed adjacent to the heater, a gas flow such that formation, along a surface of the optical fiber base material, of a flow of a gas containing a Si compound generated from the optical fiber base material heated by the heater is inhibited; and forming, while maintaining the gas flow, the drawing shape portion by pulling part of the optical fiber base material softened by being heated by the heater.

Abstract: A touch sensing device is disclosed. The touch sensing device includes one or more multifunctional nodes each of which represents a single touch pixel. Each multifunctional node includes a touch sensor with one or more integrated I/O mechanisms. The touch sensor and integrated I/O mechanisms share the same communication lines and I/O pins of a controller during operation of the touch sensing device.

Abstract: A device with a torque-proof first structural component and second structural component that is connected to the first structural component in a rotatable manner at least in certain areas. Hydraulic fluid can be supplied to lubrication points via the first and second structural components. An interface between the structural components has first and second transition areas arranged at a distance from each other in axial extension of the structural components. During operation, a pressure is applied to the first transition area which is higher than a pressure applied to the second transition area. A sealing appliance is arranged in the area of the interface between the first and second transition areas, which includes a threaded area in an area of a surface of one of the first and second structural components facing towards a surface of the other of the first and second structural components.

Abstract: A turboexpander-generator unit including a casing with a gas inlet and a gas outlet. The unit further comprises a turboexpander having a turboexpander rotor mounted on a shaft supported for rotation in the casing, and an electric generator arranged in the casing and comprised of a generator stator and a generator rotor mounted on the shaft, for co-rotation with the turboexpander rotor. The unit also comprises a plurality of bearings configured and arranged for rotatingly supporting the shaft in the casing. A gas flow path from the gas inlet to the gas outlet, which extends through the turboexpander and the electric generator. Compressed working gas expands in the turboexpander and generates mechanical power for rotating the generator rotor. The expanded working gas from the turboexpander flow through the electric generator and removes heat therefrom. The bearings comprise gas-lubricated bearings, lubricated with the working gas.

Abstract: A centrifugal compressor for compressing a refrigerant vapor in a refrigeration cycle. The compressor comprises an impeller drive shaft supported by first and second radial bearings for rotation within the compressor housing and an impeller assembly including at least one centrifugal impeller wheel mounted on the impeller drive shaft to rotate with the impeller drive shaft. The first and second radial bearings are hydrodynamic fluid bearings in which the bearing fluid is the refrigerant vapor. The compressor further comprises a conduit for supplying a portion of the refrigerant vapor from the impeller assembly to the first and second fluid bearings.

Abstract: A centrifugal compressor for compressing a refrigerant vapor in a refrigeration cycle. The compressor comprises an impeller drive shaft (28) supported by first and second radial bearings (32) for rotation within the compressor housing and an impeller assembly including at least one centrifugal impeller wheel mounted on the impeller drive shaft to rotate with the impeller drive shaft. The first and second radial bearings are hydrodynamic fluid bearings in which the bearing fluid is the refrigerant vapor. The compressor further comprising a conduit (36) for supplying a portion of the refrigerant vapor from the impeller assembly to the first and second fluid bearings.

Abstract: A closure device for monitoring leakage of a process fluid through a bore of a compressor casing is provided. The closure device may include a body configured to be detachably coupled with the compressor casing about the bore of the compressor. The body may define a fluid passage and a plurality of grooves. The plurality of grooves may be defined about an outer circumferential surface of the body and may be axially spaced from one another. The closure device may also include a plurality of seals at least partially disposed in respective grooves of the plurality of grooves. The plurality of seals may be configured to engage an inner surface of the compressor casing such that adjacent seals of the plurality of seals at least partially define an annular gap therebetween fluidly coupled with the fluid passage and configured to contain the leakage of the process fluid.

Abstract: A seal assembly seals a first portion of a machine part relative to a second portion of the machine part. The seal assembly includes at least one seal element that contacts the machine part or contacts a component connected with the machine part or that extends with a gap relative to the machine part or to the component connected with the machine part. At least one of the seal element, the machine part and the component connected with the machine part is provided or coated with a material, which has super hydrophobic properties, in the area of the seal element.

Abstract: A seal for sealing between two component parts permits a leakage flow of fluid from an upstream side of the seal to a downstream side of the seal. The seal has a jet-producing formation which produces one or more fluid jets that impinge on and thereby restrict the leakage flow.

Abstract: A shaft seal for a turbomachine is provided for sealing process side of the turbomachine against the atmosphere. The shaft seal includes a process gas seal which is acted upon by a process gas and be blocked on the process side, an atmosphere seal which is acted upon by air and be blocked on the atmosphere side, and a ventilation chamber extending around the shaft of the turbomachine. The ventilation chamber is arranged between the process gas seal and the atmosphere seal for collecting and discharging a process gas leakage that has passed through the process gas seal and an air leakage that has passed through the atmosphere seal. The ventilation chamber includes a radially inner leakage inlet, a radially outward leakage outlet and built in components that are dimensioned to as to provide a flame blocking function with regard to ignition of the leakage at the leakage inlet.

Abstract: A system and method for sealing a shaft disposed for rotation within a casing, where two axially-spaced seal rings of an oil film seal extend around the shaft and define a clearance therebetween. Oil is pumped into the clearance from an oil reservoir and a portion of the oil is received in an annular port defined in the casing between an outer labyrinth seal and one of the axially-spaced seal rings. The oil mixes with a process gas to for an oil and gas mixture. A blower is in fluid communication with the annular port and circulates the oil and gas mixture to a trap where the oil is separated from the process gas and a separated process gas is returned back to the annular port.

Abstract: The invention refers to a fluid seal arrangement for constricting a leakage flow directed through a leakage gap bordered by a rotational and a stationary component including at least one nozzle opening in the rotating and/or stationary component facing towards the rotating or stationary component of an opposite side of the leakage gap respectively in order for injecting a liquid or gaseous fluid flow through the nozzle opening into the leakage gap. The at least one nozzle opening is fluidly connected to a cooling channel inside said rotating and/or stationary component, so that said fluid flow emanating at the nozzle opening consists of a cooling fluid of the rotating and/or stationary component exclusively.

Abstract: Provide a sliding component that reduces the leakage rate of sealed fluid and significantly improves the lubrication characteristics at startup or stop, while being actuated by means of fluid lubrication in the rotation phase, thereby achieving the effects of sealing and lubrication at the same time. The sliding component is characterized in that: on one sealing face of a pair of sliding parts that slide relative to each other, multiple positive pressure-generating mechanisms that comprise extremely shallow parallel grooves running roughly in parallel with the sealing face and having submicron-level height differences are provided independently in the circumferential direction; the extremely shallow parallel grooves connect to the high-pressure fluid side, but are isolated from the low-pressure fluid side by a seal area; and extremely shallow thin grooves are formed at the bottom of the extremely shallow parallel grooves.

Abstract: An apparatus that uses a combination of mechanical contact bearings and air bearings is disclosed. The apparatus includes a fixed seal housing, attached to a process chamber and a floating seal cartridge, which is disposed in proximity to the fixed seal housing. A shaft is disposed with an aperture in the process chamber, the central opening in the fixed seal housing and the second central opening in the floating seal cartridge. A first air bearing is created between the shaft and the floating seal cartridge in the second central opening. A second air bearing is created between the floating seal cartridge and the fixed seal housing. In this way, the floating seal cartridge is free to move with the shaft radially, while still maintaining a seal between the process chamber and the external environment.

Abstract: A rotary oil feedthrough is provided for sealing off a pressurized oil compartment between a rotatable shaft and a shaft mount, where the rotary oil feedthrough displays a radial oil passage for connecting an oil duct of the shaft and/or the mount to the pressurized oil compartment in fluid-permeable fashion, and has a seal arrangement that seals off the pressurized oil compartment on both sides in the axial direction of the shaft. The rotary oil feedthrough displays a sealing ring carrier that can be fastened to the shaft or the mount in non-rotating and fluid-tight fashion, the sealing ring carrier being arranged coaxially to the shaft or the mount, and an adapter that can be positioned on the other component of shaft and mount in fluid-tight fashion, and is surrounded laterally by the sealing ring carrier in the axial direction of the shaft.

Abstract: An adjustable seal apparatus for mounting a mixing apparatus having a movable shaft in sealed engagement with a wall of a vessel and in a selected orientation with respect to the wall of the vessel. The adjustable seal apparatus includes a seal mechanism for creating a gas-tight seal between the shaft of the mixing apparatus and the wall of the vessel and an adjustable mounting mechanism for selectively positioning the shaft in a desired orientation.

Abstract: A steam seal system is disclosed. In one embodiment, the steam seal system includes: a low pressure steam turbine positioned on a shaft; a pair of end packings surrounding the shaft, each of the pair of end packings located proximate an axial end of the low pressure steam turbine along the shaft; and an pair of extraction conduits fluidly connected to the low pressure steam turbine and the shaft, the pair of extraction conduits connected to the shaft at a location axially outward of the pair of end packings and the low pressure steam turbine.

Abstract: The invention refers to an arrangement for sealing an open cavity against hot gas entrainment. The open cavity is arranged between two axially adjacent stationary components limiting radially a hot gas path of a rotary flow machine, of which at least the downstream component carries at least one airfoil extending radially into said hot gas path. A multitude of air jets is directed into the open cavity such that hot gas flowing over the open cavity is prevented from penetrating into the open cavity completely. The invention has an arrangement of supply conduits for air jets which are directed into the open cavity with a jet momentum such that hot gas is induced not to enter the open cavity and forming at least one hot gas vortex close to the hot gas path within the open cavity and preventing hot gas from penetrating into the open cavity beyond the extension of the hot gas vortex.

Abstract: A rotary supply joint that may, in particular be a rotary timing valve, is provided for providing fluid flow at least periodically from inlet ports to outlet ports when respective openings in first and second surfaces which are rotating relative to each other are aligned, in which a gas bearing is arranged to provide a bearing force between the first and second surfaces.

Abstract: A sealing system between a relatively rotating element and a stationary element has at least three sealing elements arranged between the rotating element and the stationary element and arranged in series between a process fluid and an environment, and a barrier fluid arrangement to provide a barrier fluid to spaces formed between the sealing elements. The barrier fluid arrangement has at least two compensator devices where under use the pressure in the process fluid is acting on one side of a piston in the compensator device and the pressure in the barrier fluid is acting on the opposite side of the piston. There is a difference between cross sectional areas of the two sides of the piston and the difference varies between the at least two compensator devices.

Abstract: A gear spindle includes a shaft having a first gear cavity at a first end, an oil delivery path for delivering oil to the first gear cavity and an oil return path for carrying oil away from the first gear cavity. A first seal assembly is associated with the first end of the shaft for limiting leakage of oil from the first gear cavity, the first seal assembly including a sealing interface having one side in fluid communication with the first gear cavity and an opposite side in fluid communication with a fluid delivery path. The fluid delivery path may be connected to a source of pressurized air for reducing pressure differential across the sealing interface.

Abstract: The invention relates to an improved O-ring seal for use as a high vacuum seal. A limitation of standard O-ring seals is the permeation of water through the O-ring. Especially for instruments in which parts are kept at a cryogenic temperature, such as a cryogenic electron microscope, the presence of water in the vacuum is a problem, as this results in ice growth on the cryogenic parts. As a solution often a double O-ring seal is used, or a metal seal. Both of these solutions have severe draw-backs. The invention proposes to place the O-ring in a channel in which dry gas, such as dry nitrogen, is blown. In this way no water can permeate through the O-ring, resulting in a reduced base pressure and highly reduced ice growth.

Abstract: During engine braking of a turbocharged internal combustion engine, the exhaust gas pressure increases and this is used to pressurize the seals between the turbocharger shaft and the bearing housing so as to prevent oil leakage into the compressor housing. Immediately after engine braking, stored exhaust gas pressure is used to pressurize the seals at the turbine end so as to prevent oil leakage into the turbine housing. In an alternative arrangement the exhaust gas is used to generate a reduced pressure in the bearing housing to increase the pressure gradient across the seals.

Abstract: The present invention relates to a sealing device that is configured to form a seal around a pipe by use of an air flow in order to prevent a fluid from passing the sealing device. The sealing device includes an air inlet for the inflow of compressed air and configured to be connected to a source of compressed air; one or more channels connected to the air inlet, the channels extending along a substantially annular trajectory and configured to—in use—extend substantially around the pipe; a plurality of outlet points or an annular outlet groove connected to the one or more channels, the outlet points being configured to blow the compressed air in the region of the pipe wall, in order to create an air flow about the pipe in order to prevent a fluid from passing the sealing device.

Abstract: The present invention relates to circumferential seal ring segments positioned around a rotating shaft so as to prevent fluids from leaking from a lubricant sump during both low and high pressure conditions. The circumferential seal is comprised of a plurality of adjoining annular ring segments facing the rotating shaft. Each sealing ring segment includes a dead end circumferential groove on a shaft-side face of each sealing ring such that, when the segments are joined, the circumferential dead end groove of each segment extends arcuately in the direction of shaft rotation. At least one additional groove is contained on the shaft-side face of each sealing ring segment. The additional groove(s) directs and creates pressurized air within the dead end circumferential groove, either directly or indirectly maintaining a seal between the ring segments and the shaft. A bleed hole may also be provided to create a seal between each sealing segment.

Abstract: The dry gas seal structure has a housing that houses a fluid in a supercritical state, a rotary shaft that penetrates the housing, rotation rings that rotate integrally with the rotary shaft, stationary rings that contact with the rotation rings when the rotary shaft is stopped and stationary positioned in a state in which sealing gaps are formed between the rotation rings and the stationary rings when the rotary shaft rotates, a circulating pipe path that supplies a portion of the fluid to inlet portions of the sealing gaps, a temperature-adjusting device that adjusts the temperature of the fluid flowing through the circulating pipe path, and a control unit that controls operation of the temperature-adjusting device so as to heat the inlet portions of the sealing gaps to a predetermined temperature before the rotary shaft is driven.

Abstract: The invention provides a sealing gland capable of use in high-pressure environments and methods for the use thereof. One aspect of the invention provides a sealing gland including: a first sealing surface having a first groove and a second groove, a first O-ring received in the first groove, a second O-ring received in the second groove, and a pressure port located on the first sealing surface between the first groove and the second groove. The pressure port is configured to apply a fluid pressure intermediate to a first pressure applied to the first O-ring and a second pressure applied to the second O-ring.

Abstract: The invention relates to a sealing device for a swivel, an improved attachment device and a method for improving a seal in a swivel, where a sealing medium is composed according to the viscosity and chemical composition of the application concerned and has a viscosity substantially over 500 cst and where the sealing medium is pressurized by a pressure transmission unit.

Abstract: A seal ring for a rotatable shaft in a turbo machine includes a seal body configured for disposing around the shaft wherein a radial gap is defined between an inner surface of the seal body and the shaft. An upstream surface defined by the seal body extends from the inner surface, and an annular obstruction extends from the upstream surface of the seal body, wherein the obstruction is spaced away from the inner surface.

Abstract: A seal for sealing between two component parts permits a leakage flow of fluid from an upstream side of the seal to a downstream side of the seal. The seal has a jet-producing formation which produces one or more fluid jets that impinge on and thereby restrict the leakage flow.

Abstract: A seal support system, or a kit therefor, for use with a sealing device to seal a piece of industrial equipment, includes a stand with fixed support elements for accommodating selected functional components with different sizes of components being accommodated by differently sized pipework elements. The stand has one or more substantially fixed brackets with each bracket having a component securing device at predetermined longitudinal space intervals.

Abstract: Systems for shielding a shaft from contaminants are disclosed. In one embodiment, a contaminant shield system for a shaft includes: a fluid seal disposed circumferentially about the shaft, the fluid seal substantially fluidly isolating an inner portion of the shaft from atmospheric air; an oil deflector ring disposed circumferentially about the inner portion of the shaft, the oil deflector ring having an inner surface facing a portion of the shaft exposed to a lubricating oil and an outer surface facing the fluid seal; and a fluid conduit interposed between the fluid seal and the outer surface of the oil deflector ring, the fluid conduit for receiving a fluid and releasing the fluid between the fluid seal and the outer surface of the oil deflector ring creating a positive pressure differential.

Abstract: A transport and power system having a plurality of tubes or tunnels, a magnetic levitation and linear motor train, and a superconducting power cable. One of the tubes can be an escape, power distribution, and maintenance tunnel. These tubes can be above ground, below ground, at ground, or under water.

Abstract: A shaft extending along and rotatable about an axis and a housing surrounding a portion of the shaft are provided with a seal assembly having an inner ring fixed on and rotatable with the shaft and having a pair of axially oppositely directed outer faces and a pair of outer slide rings axially flanking the inner ring and having inner faces axially sealed on the inner-ring outer faces. The outer rings, the housing, and the inner ring form an annular housing compartment surrounding the shaft. A blocking compartment on the housing is separate from the housing compartment. The inner ring is formed with a radially throughgoing passage having an inner end open on the shaft and an outer end open into the housing compartment. The housing is formed with a bore between the housing compartment and blocking compartment.

Abstract: A device for sealing a rotating shaft that penetrates a stationary housing wall has a sealing ring fastened to the housing wall and arranged between the housing wall and a shaft. The sealing ring has sealing oil supply bores supplying sealing oil into a sealing gap formed between an inner wall surface of the sealing ring and an outer wall surface of the shaft. The inner wall surface has pocket-shaped recesses where the sealing oil supply bores open. The pocket-shaped recesses extend in the circumferential direction of the sealing ring. The inner wall of the sealing ring has at least one circumferential boundary stay that delimits and seals the pocket-shaped recesses in an axial direction of the sealing ring toward the first or second housing side. The inner wall surface of the sealing ring has a circumferential groove that connects the pocket-shaped recesses to one another.

Abstract: Systems, methods and apparatus for controlling gas leakage in a turbine are provided. A plurality of seals may be provided in series, where each of the plurality of seals may be operable to reduce gas backflow from an inlet of a turbine component. Further, one or more channels may be provided that are operable to direct at least a portion of the gas backflow from respective points within the plurality of seals to corresponding points within a gas flow path of the turbine. The at least a portion of the gas backflow may be directed to the points within the gas flow path through the one or more channels. Additionally, the diameters of the plurality of seals may be optimized to at least partially balance the net thrust generated by the gas flow path of the turbine.

Abstract: An apparatus includes a manifold having a passageway through the manifold and a seal fitting extension. The seal fitting extension includes a shoulder portion having a metal seal ring. The apparatus also includes a pinch-off tube having a flange in sealed contact with the metal seal ring of the shoulder portion of the manifold. The apparatus could further include a backing element in contact with the flange of the pinch-off tube, where the backing element forces the flange into contact with the metal seal ring. In addition, the apparatus could include a sealing nut in contact with the backing element, where the sealing nut causes the backing element to force the flange into contact with the metal seal ring.

Abstract: A shaft sealing arrangement includes at least two seal rings radially enclosing a rotating shaft so as to define a clearance between the shaft and the at least two seal rings. A sealing oil supply channel is disposed between the at least two seal rings and a pump is configured for pumping a sealing oil through the sealing oil supply channel in a radial direction towards the shaft so that the sealing oil subsequently flows through the clearance in a first axial direction toward a first side of the sealing arrangement and in a second opposite axial direction toward a second side of the sealing arrangement. The sealing oil is collected on the first and second sides and at least partially reintroduced into the sealing oil supply channel.

Abstract: A rotor shaft sealing method for an oil-free rotary compressor is provided, with which occurrence of lubrication oil intrusion into the compression chamber of the compressor which is liable to occur when negative pressure is produced in the compression chamber, is prevented. With a rotor shaft sealing structure composed such that two shaft seal means are provided in the rotor casing between the oil lubricated bearing and the compression chamber such that an annular airspace is formed between the two shaft seal means, at least one communicating hole is provided to communicate the annular airspace to the outside of the rotor casing, and the annular airspace of the male rotor shaft sealing part and the annular airspace of the female rotor shaft sealing part are connected by a between-rotor shaft communication passage, pressurized air is supplied to the annular airspaces by which lubrication oil intrusion into the compression chamber is prevented.

Abstract: A hydraulic seal arrangement for a rotating machine, particularly a gas turbine engine, comprises a hydraulic seal and a hydraulic trap. When the machine is shut down, oil is retained in the hydraulic trap. When the machine is restarted, the oil from the hydraulic trap is available to re-make the hydraulic seal, thereby reducing or avoiding the leakage that typically occurs in such seal arrangements until the flow of oil through the seal arrangement is re-established.

Abstract: An air swivel ring includes a non-rotating member having an air inlet, a rotating member having an air outlet, and a split seal having a first sealing surface and coupled to one of the non-rotating member and the rotating member so that the first sealing surface on the seal is disposed proximate a second sealing surface on the other of the non-rotating member and the rotating member.

Abstract: A sealing system for use with at least one rotating shaft has a tandem seal arrangement contacting a surface of the at least one rotating shaft. The tandem seal arrangement includes at least one pair of segmented ring assemblies. Each of the segmented ring assemblies contacts the surface of the at least one shaft.

Abstract: A gap 6 between a stationary component 2 and a rotating component 4 is sealed by means of a leaf seal comprising leaves 8 having a geometry such that the centre of torsion CR of the leaf 8 is disposed upstream of the centre of pressure CP at the tip 12 of the leaf 8. As a result, the tip region of the leaf 8 is relatively stable when subjected to an air flow F, enabling damaging flutter to be suppressed.

Abstract: An arrangement (30, 80) for sealing a shaft (40, 60, 90, 110) in a casing (31, 81) by a hydraulic seal (50, 70, 100, 120) includes at least one essentially annular, radially inwardly open cavity (51, 71, 101, 121) and at least one essentially annular, radially outwardly directed sealing element (54, 74, 102, 122) which projects into the cavity (51, 71, 101, 121). To provide a hydraulic shaft seal, in which swirl and friction losses in the sealing medium are low and no leakage occurs, the hydraulic seal (50, 70, 100, 120) is arranged on the inner side (42, 62, 92) or on the outer side (111) of the shaft (40, 60, 90, 110) and the cavity (51, 71, 101, 121) or the sealing element (54, 74, 102, 122) of the hydraulic seal (50, 70, 100, 120) is connected to a wall (32, 82) of the casing (31, 81).

Abstract: In sealing arrangement 41 between first and second relatively rotatable bodies of a machine such as a steam turbine, a relatively high pressure p0 exists on one side of the sealing arrangement and a relatively low pressure pf exists on the other side. The sealing arrangement comprises a series of sealing elements or units S1, S2, S3, at least one of which comprises a brush seal. A seal bypassing device, preferably comprising a pressure relief valve 42-44 limits the pressure drop across the brush seal.

Abstract: A shaft seal which is in particular suitable for vacuum pumps, such as screw pumps, comprises an inner sealing ring (18) connectable with the shaft, and an outer sealing ring (20) surrounding said inner sealing ring (18). In the outer sealing ring (20) a circumferential groove (30) is provided into which seal gas is adapted to be fed via a feed channel (22). Further, a seal gas disk (34) is connectable with the shaft (10), the seal gas disk (34) comprising a projection (32) extending towards said groove (30). Thereby a seal gas chamber (28) is defined in the groove (30). The seal gas chamber (28) is connected with a sealing gap (40) provided between the inner and the outer sealing ring (18,20) via a chamber gap (36), through which the seal gas is adapted to flow. Adjacent to the sealing gap (40) a separating chamber (42) defined by the inner and the outer sealing ring (18,20) is arranged, the separating chamber (42) being connected with a discharge channel (44) for the purpose of discharging the seal gas.

Abstract: A fluid supply assembly for a shaft mounted device, such as an oscillating roller, is disclosed having a fluid powered apparatus comprising a shaft comprising a first fluid passageway extending through a portion of the shaft and exiting at an exit point on the shaft wall; a connector arranged on the device having a bore for receiving the shaft comprising a first seal spaced apart from a second seal within the bore along an axis parallel to the shaft, the first seal, second seal, the bore and the shaft wall defining a fluid annular chamber, and a second fluid passageway leading from the fluid annular chamber to the fluid powered apparatus wherein, in use, the exit point on the shaft wall remains between the first and second seals. The fluid supply assembly allows quick release application of fluid powered rotating devices.

Abstract: A compliant seal assembly having a seal pack carrier having an upstream face and a downstream face that defines a slot, and a seal pack having an upstream face and a downstream face slideably mounted within the slot. The seal pack carrier and the seal pack contact each other and form a high-pressure plenum and a low-pressure plenum. The compliant seal assembly also includes a first passage with a first and second opening and a second opening with a first and second opening. The first opening of the first passage is located at the upstream face of the seal pack carrier, and the second opening of the first passage communicates with the high pressure plenum. The first opening of the second passage is located at the downstream face of the seal pack carrier, and the second opening of the second passage communicates with the low-pressure plenum.

Abstract: A sealing system for a pump having a plunger includes a housing having an internal chamber adapted to receive a portion of the plunger. Primary and secondary seals are located within the internal chamber and adapted to sealingly engage the plunger. The primary seal communicates with the fluid being pumped. A barrier fluid chamber contains a barrier fluid in contact with the primary seal and the secondary seal. A pressure referencing device has an inlet port in communication with the pumped fluid and an outlet port providing fluid at a pressure magnitude equal to a peak pressure of the pumped fluid. A pressurizing device is in communication with the fluid at the peak pressure and the barrier fluid to maintain the barrier fluid pressure at a magnitude greater than the peak pressure of the pumped fluid such that the pumped fluid is restricted from leaking past the primary seal.

Abstract: A rotor shaft sealing method for an oil-free rotary compressor is provided, with which occurrence of lubrication oil intrusion into the compression chamber of the compressor which is liable to occur when negative pressure is produced in the compression chamber, is prevented.