Abstract: A drive device for a motor vehicle, having at least one drive unit and one coolant circuit for controlling the temperature of the at least one drive unit, in which at least one coolant pump is arranged in the coolant circuit for circulating an aqueous coolant in the coolant circuit. The coolant pump is designed as a screw spindle pump, in which one or more internal components are provided with a coating. The coating is designed to intentionally abrade during operation of the screw pump, thereby transferring the coating to uncoated components, while also retaining sufficient coating on the originally coated component.

Abstract: A fluid machine includes a first rotor having a first rotor first working portion and a first rotor second working portion, a second rotor having a second rotor first working portion configured to mesh with the first rotor first working portion and a second rotor second working portion configured to mesh with the first rotor second working portion and rotate independently from the second rotor first working portion.

Abstract: A screw pump with a housing; a housing cover; at least one idler screw held in a bore in the housing; and a bushing arranged on the housing cover with a receiving space bounded by a cylindrical flange, into which one end of the idler screw engages; wherein the bushing has an opening in its base, through which a fluid, supplied by a feed channel in the cover, can be supplied from the end opposite the idler screw under pressure to the end surface of the idler screw, wherein the bushing engages with radial play in a receptacle in the cover and comprises a radial flange, by which it is supported axially on the housing; and wherein at a least certain part of the ring-shaped flange of the bushing engages in the bore and is accommodated therein with play.

Abstract: A helical gear pump includes a second helical gear provided coaxially with a drive helical gear, a third helical gear engaged with the second helical gear and provided on a third shaft different from a shaft of the drive helical gear and a shaft of a driven helical gear, and a bearing for supporting the third shaft and receiving a thrust force.

Abstract: The invention relates to a double-helical gear rotary positive displacement pump comprising a pump housing (14) rotatably supporting at least a driving shaft (2) and at least a driven shaft (3), at least a first toothing (4) and a second toothing (5) being associated to said driving shaft (2) and at least a third toothing (6) and a fourth toothing (7) being associated to said driven shaft (2). The toothings (4, 5, 6, 7) have individually a helical profile that allows their mutual herringbone meshing. Three of toothings (4, 5, 6) are rigidly connected to their respective shafts (2, 3): the fourth toothing (7), or other suitable one, is idle on the shaft and axially constrained.

Abstract: In a pump system, a process fluid is directed into inlet chambers of a pump casing at an inlet pressure, and a plurality of rotors disposed inside the pump casing are rotated to pump the process fluid from the inlet chambers to an outlet chamber located between the inlet chambers, wherein the process fluid in the outlet chambers is at an outlet pressure. The process fluid is directed from the outlet chamber to a separator configured to separate particulate matter from the process fluid, and a portion of separated process fluid is directed from the separator to a gear chamber of the pump. Pump bearings are lubricated with the portion of separated process fluid from the gear chamber. Some of the portion of the separated process fluid from the pump bearing is leaked to the inlet chambers via rotor shrouds to reduce accumulation of particulate matter in the inlet chambers.

Abstract: A screw compressor includes a housing, a motor stator, a motor rotor, a helical screw rotor, a motor rotor stop, a screw fastener, and a third bearing. The helical screw rotor includes an extension section, a motor coupling section, a first supporting section, a helical screw section, and a second supporting section. The motor rotor stop includes two flange portions, wherein one flange portion is sleeved with the extension section and abuts axially upon the effective sensing section of the motor rotor. The third bearing is interposed between the other flange portion and the housing cap. The screw fastener extends through the motor rotor stop and is threadedly engaged into a thread hole of the helical screw rotor and then biases axially upon the motor rotor stop. Therefore, the motor rotor is secured more firmly, and that a compressor shaft maintains a stable running.

Abstract: A screw compressor for connecting with an economizer for gas supply, includes a main body defining a compressor cavity, a male rotor and a female rotor received in the compressor cavity, a gas-vent base defining at least one gas-supply hole therein adapted for communicating with the economizer. The male rotor and the female rotor are parallel to and meshed with each other. At least the male rotor includes at least two teeth defining at least one tooth channel therebetween. The gas-supply hole is axially aligned with the at least one tooth channel to let gas from the economizer pass therethrough and enter into the at least one tooth channel along the axial direction of the male rotor.

Abstract: A screw pump with anti-turbulent structure has a housing, at least two screw rotors parallelly mounted through the housing and engaging with each other, and a partition disposed around the at least two screw rotor. The partition may have at least two circular walls respectively formed around the rotors and an annular protrusion formed on an inner surface of the housing and being adjacent to and kept from contacting the at least two circular walls, and may be a panel having at least two mounting holes respectively mounted around the rotors. Fluids flowing in opposite directions are divided by the partition and do not encounter each other and do not become turbulent. Consequently, pressurizing efficiency of the screw pump is improved.

Abstract: The present invention provides a pump system comprising a bearing housing coupled to a pump liner, the pump liner defining a fluid conduit, the pump liner comprising a fluid inlet and a fluid outlet; and at least one rotor having a first rotor portion and a second rotor portion, the first rotor portion being disposed within the fluid conduit and the second rotor portion being disposed within the bearing housing; the first rotor portion comprising a first conveying stage adjacent to the bearing housing, and a second conveying stage adjacent to the first conveying stage, the first and second conveying stages being configured to convey a fluid, the first conveying stage being configured to convey the fluid from the bearing housing into the fluid conduit. The new pump systems rely on a dynamic restriction to reduce the need for mechanical seals between bearing housings and raw process fluid.

Abstract: A screw compressor according to the present invention includes a slide valve adapted to move forward and backward in parallel with the axis of a pair of screw rotors and also includes a plurality of hydraulic cylinders for moving the slide valve forward and backward, the plural hydraulic cylinders imparting, in synchronization with each other, a driving force to the slide valve in the same direction. With this configuration, it is possible to quicken an operation of the slide valve and improve the responsivity in volume control without increasing the diameters of pistons of the hydraulic cylinders for actuating the slide valve and without complicating equipment.

Abstract: A bearing comprising a resin layer, a backing strip and an intermediate layer which bonds the resin layer and the backing strip to each other is disclosed. The bearing undergoes a force from the resin layer side. A corrosion preventing layer is formed on each side face of the bearing so as to cover the intermediate layer. The corrosion preventing layer prevents the intermediate layer from being corroded by gas contained in an atmosphere and lubricating oil which are present around the bearing.

Abstract: A vacuum pump includes an inlet port (14) and an exhaust port (86, 88). Gas from an enclosure connected to the inlet port is pumped to the exhaust port by first and second rotors (18, 52, 254) which are mounted on first and second shafts (30, 60) extending through a pump chamber (112). The rotors are connected with shaft sections (140, 150, 240, 250) which include a lobe (142, 172, 242, 242?) extending from the shaft sections and a mating channel (152, 182, 252, 252?) defined in the other. The lobes matingly engage the channels during rotation of the rotors to form a suction section (154). The suction section (154) compresses a volume of gas entering the pump from the inlet port (14) reducing the power consumed to move the volume of gas through the pump chamber more easily and increase pump efficiency.

Abstract: A screw-type pumping unit (51) for treatment of fluids in several phases comprises a case (54) which contains a pumping chamber (62), inside which there are accommodated at least two screws (70a, 70b), one of which (70a) is a drive screw, and supports at one of its ends a first gear (108a), which engages with a second gear (108b), which in turn is supported at one end of a driven screw (70b). The first and the second gear (108a, 108b) are contained in a casing (110) which is fitted onto them, and is provided with at least two through holes (112, 114) produced in two substantially opposite portions, through one of which oil can be admitted into the casing (110), and wherein the oil can be discharged through the other through hole (114), such that the casing (110), together with the gears (108a, 108b), forms a gear pump which can keep the lubrication oil of the pumping unit (51) circulating.

Abstract: A vacuum pump includes an inlet port (14) and an exhaust port (86, 88). Gas from an enclosure connected to the inlet port is pumped to the exhaust port by first and second rotors (18, 52, 254) which are mounted on first and second shafts (30, 60) extending through a pump chamber (112). The rotors are connected with shaft sections (140, 150, 240, 250) which include a lobe (142, 172, 242, 242′) extending from the shaft sections and a mating channel (152, 182, 252, 252′) defined in the other. The lobes matingly engage the channels during rotation of the rotors to form a suction section (154). The suction section (154) compresses a volume of gas entering the pump from the inlet port (14) reducing the power consumed to move the volume of gas through the pump chamber more easily and increase pump efficiency.

Abstract: A pump system for the selected injection of one or more fluids is disclosed where the system generally includes a flow meter including a means to translate the flow rate through the meter to one or more pumps coupled to the meter such that upon a selected introduction of fluid flow through the meter a selected amount of fluid is pumped through the one or more pumps.

Abstract: A gear pump exhibiting improved efficiency over a broader range of fluid viscosity and pump speed includes a compression zone defined between each of a pair of pump gears and internal walls of a gear chamber, wherein the compression zones have a non-uniform thickness along a longitudinal direction of the gears. The geometry of the compression zones provides a mechanism whereby the drag of the viscous fluid which is induced by the rotation of the pump gears carries the viscous fluid through a progressively narrower gap in the direction of rotation ending in a final smooth pinch-off at the start of the seal zone. The geometry of the compression zone maximizes the drag and pressurization of the viscous fluid being pumped into the teeth of the gears, thereby assisting in the complete filling of the teeth. The result is improved fill efficiency over a broader range of pump speeds and over a broader range of fluid viscosity.

Abstract: The invention relates to a fluid-conveying machine, in particular, a pump having a component rotating in a stationary housing part inside an annular gap. The stationary housing part separates an interior having a higher product pressure from an exterior having a lower pressure. A rotating component is mounted in an external bearing which is sealed with respect to the interior via a sealing system. In order to improve the sealing, the invention provides that the annular gap is formed between two sliding bearing shells which comprise extremely hard, wear-resistant materials and, in accordance with the operating principle of a radial sliding bearing, form a first pressure-reducing stage. A feedback device, which feeds back the leakage from this first sealing stage into the conveying process of the machine, is connected downstream of the first pressure-reducing stage. A second sealing stage is arranged axially downstream of the feedback device.

Abstract: A screw compressor or pump includes: a housing, two intermeshing rotors respectively rotatably mounted in the housing by two shafts; each rotor having a helix tooth spirally formed on the rotor lengthwise, with the helix tooth gradually decreasing an outer diameter of a top land surface of the helix tooth corresponding to a gradually contracted rotor chamber, and having a spiral groove juxtapositioned to the helix tooth and spirally formed in the rotor lengthwise; the spiral groove having a groove bottom surface extrapolatively defining an inner cone tapered towards a suction port side; the rotor chamber having a conical wall surface extrapolatively defining an outer cone tapered towards a discharge port side, thereby forming a gradationally contracted cavity between the spiral groove and the conical wall surface of the rotor chamber as confined between the inner and outer cones for increasing the compression or pumping efficiency.

Abstract: There is disclosed an apparatus for pumping multiphase fluids in oil field production, particularly a twin-screw pump for providing a large pressure boost to high gas-fraction inlet streams. The pump includes a housing having an internal rotor enclosure, the enclosure having an inlet and an outlet and a plurality of rotors operably contained in the enclosure. Each rotor has a shaft and a plurality of outwardly extending threads affixed thereon, the rotors being shaped to provide a non-uniform volumetric delivery rate along the length of each rotor. The pump also has means for rotating the rotors, whereby a fluid stream entering from the inlet is subjected to a pumping action to transport the fluid stream to exit the rotor enclosure through the outlet. In one embodiment, the rotors have a plurality of threaded pumping stages separated by unthreaded non-pumping chambers.

Abstract: Twin-screw pump, wherein the four conical screws are vertically arranged and are fed with biphase fluid at the two ends, independently of each other, by means of a stream divider and wherein the two screw shafts each have a central axial drilling which connects the delivery chamber to a series of radial channels which end up on the tip of the single teeth of the screws. A preferen-tial stream divider is described.

Abstract: The invention relates to a pumping process for operating a multi-phase screw pump with at least one feed screw surrounded by a housing having at least one inlet on one side and at least one outlet at its top, in which the intake medium is conveyed parallel to the screw shaft in a continuous low-pulsed stream and continuously discharged at the outlet. This invention also relates to a multi-phase screw pump. In order to prevent the drawbacks usually occurring in dry running phases, the invention proposes that a partial liquid volume flow (liquid circulation) be separated on the pressure side and returned in metered quantities into the intake regions and thus kept in circulation.

Abstract: A ceramic helical rotor expander using a double-ended or tandem herringbone type rotor arrangement with bearing and seal assemblies remote from the hot gas inlets and especially capable of operating at an inlet temperature of above 1100.degree. C. The rotors are solid or hollow and bonded to hollow metal shafts, and mounted in a composite or simple prismatic casing. The rotors, casing and shafts are constructed from low expansivity materials. In the preferred embodiment the rotors are constructed of silicon nitride and the shafts constructed of an molybdenum alloy, with the metal shafts being supported in bearings and secured to synchronizing gears. The rotors and casing may be provided with coolant channels therein, and are constructed to eliminate the problem of end leakages at inlet temperature and pressure, and the need for high temperature bearings and seals.

Abstract: A multi-stage screw vacuum pump having a reduced number of constituent parts as compared with the conventional one and a reduced overall size. The multi-stage screw vacuum pump comprises an input mechanism for transmitting a driving force derived from a driving source to a former-stage pump, and speed up mechanisms for speeding up the rotation of the former-stage pump for transmission to a latter-stage pump.

Abstract: Improvements in screw pumps, and especially positive displacement pumps, are disclosed. The clearance between the screw flight and the bore is increased over an increased period. The screw is balanced at preferred locations on the flight. Wear hard material such as tungsten carbide is emplaced on a portion of the outer surface of the screw flight. A wear measurement port extends from the outside surface of the pump to the inner surface of the bore. Pressure regulating ports and controls provide an active pressure feedback control system to control the feeding of pressure from the outlet end of the screw back toward the inlet end of the screw. Pump wear, and pressure pulsations in the operation of the pump are thus reduced. The wear measurement port enables a method of monitoring wear on the pump screw during operation without disassembling the pump, namely by manipulating a wear measurement device through the port. The wear measurement device can be a proximity sensor which can be connected to a monitor.

Abstract: A melt pump comprises a pump housing having an intake port and a discharge port and a pair of gear rotors. Each of the pair of gear rotors having a gear part and a shaft part integrated with each other, which are arranged within the pump housing in such a manner as to be rotatable in mutually meshing condition. The melt pump further comprises a recovering passage for guiding resin leaking through a clearance between the pump housing and each of the pair of gear rotors into the intake port, a cooling hole drilled inside each of the gear rotors while facing to each clearance forming region; and a pipe inserted into the cooling hole for supplying cooling liquid. A sleeve for lining the internal periphery of the cooling hole is located in the hole so as to utilize the inside of the sleeve as a cooling liquid passage.

Abstract: A molecular drag pump for delivering a gas under molecular flow conditions comprises a pair of parallel, helically threaded rotors rotatably mounted in a stationary housing. The rotors have respective helical threads and respective helical grooves, and are held in close mesh with each other. The helical threads are helically inclined in one direction to the axes of the rotors, and have a flank angle such that the helical threads are closely received in the respective helical grooves while keeping the threads out of contact with each other. The rotors are rotated in one direction about their respective axes to move a gas introduced through an inlet port toward an exhaust port axially along the rotors.

Abstract: A screw displacement pump (10) for comingled material has a body (11) defining a chamber (12'). Inlets are provided for the admission of fluid to the chamber and an outlet is provided for discharge of fluid from the chamber (12') intermeshing screw members (40) are mounted for rotation within the chamber (12') for transporting comingled material from the inlet to the outlet, the threads (41,42) of the intermeshing screw members (40) being of opposite hand. The pitch of the screws (40) at the outlet end thereof is smaller than the pitch of the screws (40) at the inlet end thereof to cause compression of gaseous material being transported. Clearance is provided between the screws (40) and between the screws (40) and the walls of the chamber (12') to allow sufficient leakage of the material towards the inlet, when the material is in the liquid phase, to avoid a liquid lock.

Abstract: A gear pump for injection molding and extrusion of elastomer material, where the material is inserted in strip form through slots into tooth spaces in a known manner. The gears have circumferential grooves in their mid portions, and a tongue is inserted into the groove in the region of gear engagement. Dividing-and-sealing members are fitted into the gear grooves at locations between the region of engagement and the insertion slots for the elastomer strips.

Abstract: A dynamic cooler apparatus is provided for dynamically cooling molten plastic extrudate while pumping metered amounts of that extrudate to an extrusion die or the like. The dynamic cooler apparatus utilizes bi-helical gears in a gear pump configuration in a housing in which a heat exchange medium is circulated. The heat exchange medium is also circulated internally of the gears so that the gear teeth and the housing act to cool discrete volumes of extrudate from four sides defined by the gear teeth and the internal surface of the housing. The bi-helical gears are driven to minimize loading between the teeth thereof and to permit the teeth to be as small as practical to present more cooling surface for a given cross-section of extrudate and optimize the heat transfer capability of the dynamic cooler apparatus. Provision is also made to use the molten extrudate as a lubricant for the shafts and bearings of the bi-helical gears.

Abstract: Plastics recovery, compounding and fabricating apparatus is disclosed utilizing a gear pump specially designed to include a media free space between the gear face and side walls with minimum sealing to improve volumetric pump efficiencies and provide pumping capacity insensitivity to viscosity over a wide range.

Abstract: An axially shiftable slide valve member in a rotary, helical screw compressor carries a port which senses the pressure of the working fluid in the trapped volume just before uncovering of the closed thread to the discharge port and compares that pressure with the line pressure at the discharge port and shifts the slide valve member to balance the pressures and prevent overcompression or undercompression of the compressor. The screw compressor may be provided with two identical but oppositely oriented slide valve members on opposite sides of the intermeshed helical screws with one slide valve member controlling the capacity of the compressor and the other balancing the closed thread pressure at discharge with discharge line pressure. Compressor rotation may be reversed to eliminate the need for a reversing valve where the compressor operates in heat pump or reverse flow defrost refrigeration applications, with the two slide valves trading functions.

Abstract: An axially shiftable slide valve member in a rotary, helical screw compressor carries a port which senses the pressure of the working fluid in the trapped volume just before uncovering of the closed thread to the discharge port and compares that pressure with the line pressure at the discharge port and shifts the slide valve member to balance the pressures and prevent overcompression or undercompression of the compressor. The screw compressor may be provided with two identical but oppositely oriented slide valve members on opposite sides of the intermeshed helical screws with one slide valve member controlling the capacity of the compressor and the other balancing the closed thread pressure at discharge with discharge line pressure. Compressor rotation may be reversed to eliminate the need for a reversing valve where the compressor operates in heat pump or reverse flow defrost refrigeration applications, with the two slide valves trading functions.