Abstract: A vacuum pump (50) includes a pumping arrangement, a shaft (10) for driving the pumping arrangement, a motor (60) for rotating the shaft (10) and a bearing arrangement supporting the shaft (10) for rotation, the bearing arrangement having a rolling bearing (12), supporting a first portion of the shaft (10), and a thrust bearing (30). The thrust bearing (30) houses a plurality of rolling elements (36) such that they are maintained in bearing contact with an outer race (18) of the rolling bearing (12) and a race (34) of the thrust bearing (30). In this way axial movement of the rolling bearing (12) can be resisted whilst allowing radial movement of the rolling bearing (12).

Abstract: An apparatus for tuning pump speed at an optimal or desired speed using an automated method is disclosed. The apparatus includes a vacuum pump connected to a chamber for evacuating gas from the chamber. A sensor measures one or more characteristics, such as pressure, of the gas in the chamber. The measured characteristic is compared to a predetermined value. The speed of vacuum pump is adjusted based on the comparison until it falls in a desired range.

Abstract: The present invention provides a pumping system (60) comprising: a pumping mechanism (64); a motor (51) for driving the pumping mechanism; a drive control (50) for controlling the motor; and means (52) for monitoring at least one state within the system; wherein, to improve the performance of the system, the drive control causes the system to operate for transient periods in an overload condition which can result in said monitored state exceeding a predetermined operational limit, and when operating in said overload condition said drive control controls the power to the motor dependent on the level of said monitored state thereby avoiding said state from exceeding said operational limit.

Abstract: A rotor for a screw vacuum pump has a threaded body in which a central cavity is formed. A coolant is supplied to the cavity from a supply line provided in a shaft attached to the body. A coolant flow guide, which may be either separate from or at least partially integral with the shaft, is located within the cavity. The flow guide has an outer surface adjacent, preferably in contact with, the body to enable heat to the transferred from the rotor to the guide. The guide also has an inner surface defining a bore, and defines at least in part a plurality of axially extending slots radially spaced from and in fluid communication with the bore. In use, coolant flows into the cavity through the bore of the guide, and out from the cavity through the axially extending slots, extracting heat from the guide as it flows both into and out form the cavity. The discharged coolant is conveyed form the slots into a discharge line located within the shaft.

Abstract: A method of monitoring the condition of a pump (10) or at least one component of a system that includes a pump which component or components are not a part of the pump, includes the step of generating a predetermined test condition in the pump or system component or components. During a period in which such a test condition is present, signals indicative of the pump or system component or components are obtained. Wear in the pump bearings, the build-up of deposits in the pump or in pipework forming a part of the pump system can be detected or predicted and corrective action taken before the pump or system fails. By providing a method of monitoring pump or system condition in-situ, it is possible to reduce the likelihood of pump failure in use and the need to carry out over frequent servicing of the pump.

Abstract: A vacuum pump surrounded by a ballistic blanket.

Abstract: At least one gaseous impurity, for example silane, is removed by absorption from a feed gas stream, for example a gas stream comprising nitrogen and hydrogen, the gaseous impurity being less volatile than the feed gas stream. The absorption is effected by a sub-cooled absorbent at a first cryogenic temperature and a first pressure. The absorbent is typically propane. The absorption may be conducted in a liquid-vapour contact column (130). Absorbent containing impurity may be regenerated in a regeneration vessel 150 and returned to the column (130).

Abstract: A purifier is described for use in a gas processing application. The purifier comprises a chamber having a gas inlet and a gas outlet. A series of baffles are arranged in the chamber and coated with a getter material selected for its ability to react with species to be removed from a gas stream and form stable compounds. The chamber also houses a source of the getter material, which is periodically activated to refresh the coating of getter material on the baffles.

Abstract: A system for evacuating an enclosure is provided. The system includes a first vacuum pump having an inlet selectively connectable to an outlet from the enclosure. A second vacuum pump is also provided together with a conduit for connecting an exhaust of the first vacuum pump to an inlet of the second vacuum pump. An auxiliary chamber is provided, this chamber being selectively connectable to the conduit such that, in a first state, gas can be drawn from the auxiliary chamber by the second vacuum pump in isolation from the enclosure, and, in a second state, gas can be drawn from the enclosure to the auxiliary chamber through the first vacuum pump.

Abstract: A system (100) for supplying an inert purge gas to a pumping arrangement (106) includes a plurality of flexible capillary tubes (102) each for conveying the gas from a respective outlet of a manifold (12) to a respective port (104) of the pumping arrangement (106). The internal diameter and length of each tube (102) control the gas flow rate to the respective port (104).

Abstract: A vacuum pumping system comprises a vacuum pumping arrangement comprising: a drive shaft; a motor for driving said drive shaft; a molecular pumping mechanism comprising a turbomolecular pumping mechanism; and a backing pumping mechanism. The drive shaft drives said molecular pumping mechanism and said backing pumping mechanism. The system also comprises an evacuation mechanism, such as a load lock pump, for evacuating at least, said turbomolecular pumping mechanism.

Abstract: Apparatus for the combustive destruction of noxious substances comprises an annular combustion zone (C14) surrounded by the exit surface of an inwardly fired foraminous burner (C32) and surrounding the exit surface of an outwardly fired foraminous burner (C42), means (C12) for injecting a gas stream containing at least one noxious substance into the combustion zone, and means for supplying fuel gas and oxidant to the foraminous burners to effect combustion at the exit surfaces.

Abstract: A trap device (18) for removing species from a gas stream drawn from an enclosure by a vacuum pump is described, the device (18) comprising a casing having an inlet (16) for receiving the gas stream, an outlet (20) for exhausting the gas stream from the casing, and first and second chambers (136, 138) each for receiving the gas stream from the inlet and conveying the gas stream to the outlet; means (170, 174) for selectively diverting the gas stream from the inlet to a selected one of the chambers; a first plurality of cartridges (32) each being removably insertable into the casing to provide a plurality of flow passages for gas passing through the first chamber; and a second plurality of cartridges (132) each being removably insertable into the casing to provide a plurality of flow passages for gas passing through the second chamber, each flow passage extending between an inlet and an outlet of a respective cartridge, each cartridge housing means for removing species from the gas passing therethrough as soli

Abstract: A differentially pumped mass spectrometer system comprises a mass spectrometer having a plurality of pressure chambers; a vacuum pump attached thereto and comprising at least three pump inlets, a first pumping section, a second pumping section downstream from the first pumping section, and a third pumping section downstream from the second pumping section, an outlet from a first, relatively low, pressure chamber being connected to a first pump inlet through which fluid can enter the pump from the first chamber and pass through the first, second and third pumping sections towards a pump outlet, an outlet for a second, medium pressure chamber of the spectrometer being connected to a second pump inlet through which fluid can enter the pump and pass through, of said sections, only the second and third pumping sections towards the pump outlet, and an outlet for a third, highest pressure chamber of the spectrometer being connected to a third pump inlet through which fluid can enter the pump and pass through, of sai

Abstract: A pump enclosure includes a base, a plurality of pillars, and a cover. One of the pillars includes interconnecting aluminium extrusions defining therebetween a housing for pump control circuitry. This pillar can also provide a heat sink for dissipating heat generated during use of a pump away from the control circuitry.

Abstract: A differentially pumped system comprises a plurality of pressure chambers; and a pumping arrangement (100) attached thereto for evacuating the chambers, the pumping arrangement comprising first and second compound pumps (102, 104) each comprising at least a first inlet (120); (124), a second inlet (122); (126), a first pumping section (110) and a second pumping section (112) downstream from the first pumping section, the sections being arranged such that fluid entering the pump from the first inlet passes through the first and second pumping sections and fluid entering the pump from the second inlet passes through, of said sections, only the second section, wherein the first inlet (120) of the first pump (102) is attached to an outlet from a first, relatively low, pressure chamber (10), the second inlet (122) of the first pump (102) and the first inlet (124) of the second pump (104) are attached to an outlet or respective outlets from a second, common medium pressure chamber (16), and the second inlet (126) o

Abstract: An organic contaminant molecule sensor is described for use in a low oxygen concentration monitored environment. The sensor comprises an electrochemical cell, which is formed from a measurement electrode coated with (or formed from) a catalyst having the ability to catalyse the dissociative adsorption of the organic contaminant molecule, the electrode being positioned for exposure to the monitored environment, a reference electrode coated with (or comprised from) a catalyst selected for its ability to catalyse the dissociation of oxygen to oxygen anions, the reference electrode being positioned within a reference environment, and a solid state oxygen anion conductor disposed between and bridging the measurement and reference electrodes, wherein oxygen anion conduction occurs at or above a critical temperature, Tc. Sealing means are provided for separating the reference environment from the monitored environment.

Abstract: A method for scrubbing a halogen-containing gas, comprises contacting the halogen-containing gas with water at a temperature of at least 30° C., the gas optionally subsequently being subjected to a further treatment step comprising contacting it with water at a temperature of less than 30° C. and/or a gas dilution step. An apparatus for carrying out the method comprises a hot wash chamber (6) and optionally a cold wash chamber (7) and/or a gas dilution device (13).

Abstract: Apparatus for treating a gas stream comprises a plurality of cylindrical proton conducting membranes. The gas stream is conveyed through the bore of each cylindrical membrane, and a hydrogen-containing gas is conveyed about the external surface of each cylindrical membrane. A catalyst provided on the inner side of each membrane catalyses a reaction between a halogen-containing component of the gas stream, such as CF4, adsorbed on the surface of the catalyst and protons conducted through the membrane.

Abstract: A vacuum pump includes a rotor assembly mounted on a driven shaft, and a motor for rotating a drive shaft in forward and reverse directions. A drive member on the drive shaft engages a driven member on the driven shaft. Each member has first and second impact surfaces. The members are configured to permit at least one quarter of a revolution of the drive member relative to the driven member in either the forward or the reverse direction before one of the impact surfaces of the drive member impacts upon a corresponding impact surface of the driven member. This enables the drive member to acquire sufficient angular momentum before it impacts the driven member such that the amount of energy transferred to the driven shaft upon impact can be sufficient to free a pump that has become locked by process deposits.