Abstract: A connected impeller and shaft is provided. The shaft has a first part which provides a threaded portion carrying a thread which screws onto a corresponding threaded portion of the impeller. The shaft also has a second part which provides an abutment surface for engaging a corresponding abutment surface of the impeller when the threaded portions are screwed together, thereby tightening the threads to provide a rotationally fixed connection between the impeller and the shaft. The first part is rotationally fixed relative to the second part at a joint. The threaded portion of the shaft is axially spaced a first distance from the abutment surface of the shaft. The threaded portion of the shaft is axially spaced from the joint by a second distance which is greater than the first distance. The threaded portion of the shaft and the joint are on the same side of the impeller.

Abstract: A turbocharger has a casing system which houses a centrifugal impeller connected to a turbine by a shaft. The casing system includes an insert casing which forms a duct for feeding air to and through the impeller, and a volute casing which forms a volute for receiving compressed air from the impeller, the insert casing inserting into the volute casing. The casing system further includes a main casing which forms a housing for the shaft and for the shaft-side end of the impeller. The impeller includes a hub which has a radially outer annular rim, and has front and rear faces which converge towards the rim from respectively the inlet side and the shaft side of the hub. The impeller further includes a plurality of circumferentially arranged vanes on the front face of the hub. The impeller further includes a seal formation formed on the rear face at the rim.

Abstract: A connector for connecting an impeller to a shaft is provided. The connector is formed as a unitary body. The connector has a sleeve portion which is frictionally connected on a radially outer surface of a shaft-side hub extension of the impeller. The connector further has a threaded portion carrying a thread which screws onto a corresponding threaded portion of the shaft, such that the connector provides a rotationally fixed connection between the impeller and the shaft. The hub extension has a central recess, and a part of the connector is inserted into the recess. The frictional connection between the sleeve portion and the radially outer surface of the hub extension transmits, in use, substantially all of the torque between the shaft and the impeller.

Abstract: A turbocharger has a casing system which houses a centrifugal impeller connected to a turbine by a shaft. The casing system includes an insert casing which forms a duct for feeding air to and through the impeller, and a volute casing which forms a volute for receiving compressed air from the impeller, the insert casing inserting into the volute casing. The casing system further includes a main casing which forms a housing for the shaft and for the shaft-side end of the impeller. The impeller includes a hub which has a radially outer annular rim, and has front and rear faces which converge towards the rim from respectively the inlet side and the shaft side of the hub. The impeller further includes a plurality of circumferentially arranged vanes on the front face of the hub. The impeller further includes a seal formation formed on the rear face at the rim.

Abstract: A connector for connecting an impeller to a shaft is provided. The impeller has a shaft-side hub extension with a central recess. The impeller is formed of a material having a greater coefficient of thermal expansion than the material of the shaft. The connector is inserted into the recess to frictionally connect an outwardly facing surface of the connector with a radially inner surface of the hub extension. The connector has a threaded portion carrying a thread which screws onto a corresponding threaded portion of the shaft, such that the connector provides a rotationally fixed connection between the impeller and the shaft. The connector is formed of a material having a coefficient of thermal expansion which is greater than the coefficient of thermal expansion of the material of the shaft.

Abstract: A connector for connecting an impeller to a shaft is provided. The connector is formed as a unitary body. The connector has a sleeve portion which is frictionally connected on a radially outer surface of a shaft-side hub extension of the impeller. The connector further has a threaded portion carrying a thread which screws onto a corresponding threaded portion of the shaft, such that the connector provides a rotationally fixed connection between the impeller and the shaft. The hub extension has a central recess, and a part of the connector is inserted into the recess. The frictional connection between the sleeve portion and the radially outer surface of the hub extension transmits, in use, substantially all of the torque between the shaft and the impeller.

Abstract: A two-stage turbocharger assembly for an internal combustion engine is provided. The assembly has a single low pressure turbocharger, and more than two high pressure turbochargers arranged in parallel with each other. The compressor outlet of the single low pressure turbocharger is operatively connected to the compressor inlets of the high pressure turbochargers. The turbine outlets of the high pressure turbochargers are operatively connected to the turbine inlet of the single low pressure turbocharger.

Abstract: Disclosed is an air intake for a turbocharger for an internal combustion engine, said air intake including a series of variable position guide vanes for directing the air such that it is swirling in a rotational sense on reaching the impeller of the compressor of the turbocharger. The variable position guide vanes are made comprised of sound absorbent material such as to achieve a substantial reduction in turbocharger noise at the air intake.

Abstract: A two-stage turbocharger assembly for an internal combustion engine is provided. The assembly has a low pressure turbocharger, and more than two high pressure turbochargers arranged in parallel with each other. The compressor outlet of the low pressure turbocharger is operatively connected to the compressor inlets of the high pressure turbochargers. The turbine outlets of the high pressure turbochargers are operatively connected to the turbine inlet of the low pressure turbocharger.

Abstract: A rotating machine, has a rotary component, which includes a memory device for storing data relating to the past use of the component. The data are associated with rotational speed and ambient temperature, which are detected by detectors either on or off the rotary component. The stored data may be the raw temperature and speed data as sampled over time, which are then used to derive values of low-cycle fatigue and creep damage. These fatigue and creep values are, in turn, correlated with the load profiles of the component to arrive at a value of elapsed lifespan for the component. Alternatively, the stored data may be the fatigue and creep values and/or, preferably, values of elapsed and remaining lifespan of the component. In a second embodiment the detectors are located on the machine casing along with an evaluation unit.

Abstract: A method for cleaning a number of turbine blades of a turbine under operation conditions by means of a cleaning fluid which is sprayed onto the turbine blades by a number of nozzles is disclosed. The method is characterised in that the cleaning fluid is distributed to the nozzles such that only a fraction of the nozzles is used at any one time to spray the cleaning fluid onto the turbine blades. Furthermore, a turbine comprising a number of rotor blades, a number of stator blades and a number of nozzles is described. Each nozzle is connected to a cleaning fluid supply. The turbine further comprises at least one distribution unit which is configured such that the cleaning fluid can be distributed to only a fraction of the nozzles at any one time. Moreover, a turbocharger comprising an inventive turbine is disclosed.

Abstract: An impeller having a rotation axis, a radial direction, a backplate and a number of vanes which are connected to the backplate at a line of connection is provided. Each vane has an upstream side, a downstream side and an outer side. The downstream side of each vane has an edge portion which is located near the outer side. The vanes project radially over the backplate and the downstream side further includes a connecting portion connecting the edge portion to the backplate and including an angle with the radial direction. The connecting portion includes a convex rounded portion which is located near the line of connection. Moreover, a turbocharger having an inventive impeller is disclosed.

Abstract: An impeller is provided with a back surface that is at least partly coated with a thermal barrier coating. The thermal barrier coating includes an anodized layer, polymer or polymer-based ceramics.

Abstract: Disclosed is an air intake for a turbocharger for an internal combustion engine, said air intake including a series of variable position guide vanes for directing the air such that it is swirling in a rotational sense on reaching the impeller of the compressor of the turbocharger. The variable position guide vanes are made comprised of sound absorbent material such as to achieve a substantial reduction in turbocharger noise at the air intake.