Abstract: A shaping apparatus for shaping a workpiece. The apparatus comprises first and second pairs of shaping members and a spacer located between the first and second pairs of shaping members. The first pair of shaping members comprises a material having a first linear coefficient of thermal expansion, and the second pair of shaping members comprises a material having a third linear coefficient of thermal expansion. The first linear coefficient of thermal expansion is higher than the second linear coefficient of thermal expansion such that on heating of the apparatus, thermal expansion of the shaping members causes the first pair of shaping members to expand outwardly, and the second pair of shaping members to expand inwardly.

Abstract: A gas turbine engine has, in flow series, a compressor section, a combustor, and a turbine section. The gas turbine engine further has a system for cooling the turbine section and providing tip clearance control between turbine blades and circumferentially distributed segments forming an annular shroud surrounding the blades outer tips. The turbine section cooling sub-system diverts a first cooling air flow, regulated by a first valve arrangement, from the compressor section to a heat exchanger and then to the turbine section to cool its components. The tip clearance control sub-system supplies a second cooling air flow, regulated by a second valve arrangement, to an engine case where the segments are mounted, which regulates thermal expansion of the case and controls the clearance between the segments and outer tips. The system further includes a closed-loop controller which issues demand signals to the first and second valve arrangements.

Abstract: This invention relates to a heat exchanger, comprising a plurality of stacked corrugated plates, each plate having a plurality of parallel main corrugations each having longitudinal peak ridges and trough ridges, wherein either or both of the peak ridges and trough ridges have an undulating profile so as to define a plurality of summits in a common plane.

Abstract: An air riding seal arrangement comprises two components 8, 12 which are relatively rotatable so that aerodynamic forces causes a supporting air film to be generated between them. At least one of the components 8, 12 comprises a cylindrical surface 22, 24 provided with a rib 26, 28. The rib 26, 28 serves to restrict the flow of liquid, such as lubricant, deposited on the cylindrical surface 22, 24 towards the gap between the components 8, 12. The rib further serves to draw lubricant away from the gap by surface tension effects, when both of the components 8, 12 are stationary.

Abstract: An apparatus and process is disclosed for the treatment of a component using a fluidised bed of powder. The apparatus includes a treatment chamber for receiving at least a treatment part of the component and a powder reservoir. The powder reservoir has heating or cooling means for controlling the temperature of the powder. A flexible powder conveyor (e.g. educator) links the treatment chamber and the powder reservoir, continuously conveying powder from the reservoir to the treatment chamber for use in the fluidised bed. The powder reservoir and the treatment chamber are independently positionable, so that the position of the treatment chamber is variable with respect to the powder reservoir during operation of the apparatus.

Abstract: A bearing arrangement 2 comprising an outer race 10, a shaft 4 arranged to rotate with respect to the outer race 10 thereby defining an axis of rotation 8 of the shaft 4. The shaft 4 and the outer race 10 are arranged to define a region of overlap between the shaft 4 and the outer race 10 along the axis of rotation. An inner race 12 is disposed between the outer race 10 and the shaft 4 in the region of overlap and coupled for rotation with the shaft 4, the inner race 12 and the shaft 4 defining an annular reservoir 40 between them for accommodating radial expansion of the shaft 4 or radial displacement of the shaft 4 with respect to the axis of rotation 8.

Abstract: A flexible mandrel 100 has a plurality of flexible elements 130 extending between two spaced flanges 110, 120. A means for adjusting the radial position of each of the flexible elements 130 along the length of the mandrel 100 between the flanges 130 enables the plurality of flexible elements 130 to be configured in a variety of symmetrical and asymmetrical forms. Conventional composite fibre or tape laying techniques may then be used to form one-piece, revolute, composite components. The flexible mandrel 100 can then be collapsed and withdrawn from the interior volume 202 of the formed component.

Abstract: An apparatus for the treatment of a component using a fluidised bed of powder fluidised by a gas flow has a treatment chamber for receiving at least a treatment part of the component and for containing the fluidised bed. A fluidising gas inlet provides fluidising gas to the treatment chamber and a fluidising gas outlet removes used fluidising gas from the treatment chamber. A powder screen is located between the treatment chamber and the fluidising gas outlet, the powder screen operable substantially to prevent loss of powder from the fluidising bed entrained in the fluidising gas removed from the treatment chamber. The treatment chamber can be small and moveable, and then applied to a part of a component to be treated. Heating of the fluidised bed may be provided by heating of the fluidising gas in a fluidising gas reservoir remote from the treatment chamber.

Abstract: A stator vane assembly for a gas turbine engine includes circumferentially spaced vanes about a common axis. The array of vanes further includes three or more sub-arrays, which are configured such that the vane spacing in one sub-array is different from the vane spacing in the other sub-arrays.

Abstract: A component is treated in a fluidised bed by insertion of only a treatment part of the component into the treatment chamber of a fluidised bed apparatus. The non-treatment part of the component is located substantially outside the treatment chamber and out of contact with the fluidised bed. The boundary between the treatment part and the non-treatment part of the component is defined by a boundary containment surface at a fixed location with respect to the component. The boundary containment surface may be a seal which seals between the component to be treated and an aperture in a side wall of the treatment chamber.

Abstract: A method of forming a slot in an disc for use in a gas turbine. The method includes providing a rough formed slot with a V configuration and then milling the slot using a conical milling tool or an angled cylindrical tool to provide undulations in the wall of the slot. The milling tool traverses through the slot following a trochoidal path.

Abstract: A method of determining the actual position of a control surface (27). The method comprises receiving a signal (34) representative of a required position of the control surface (27), repositioning the control surface (27) in response to the signal (34) by moving an actuator (26), measuring a secondary position indicator, calculating the actual position of the control surface (27) on the basis of the secondary position indicator and, comparing the actual position with the required position.

Abstract: Adding silicon, in a defined range of weight percentage, to the composition of a known nickel-based alloy improves oxidation, hot corrosion and dwell crack growth resistance without the detrimental effects on the thermal stability of the microstructure and on other material properties that have been found with known alloys. In a particular preferred embodiment the alloy has the following composition (in weight percent): chromium 14.6-15.4%; cobalt 18-19%; molybdenum 4.75-5.25%; aluminium 2.8-3.2 titanium 3.4-3.8%; tantalum 1.8-2.2%; hafnium 0.4-0.6%; carbon 0.020-0.034%; boron 0.005-0.025%; silicon 0.2-0.6%; the remainder being nickel and incidental impurities.

Abstract: Rotary friction welding apparatus comprising a clamp having a backstop for locating a part to be welded by rotary friction welding and a lateral clamp for applying lateral loads to the part to be welded; and a forge for applying forge pressure to the part to be welded when the part is located in the clamp, the clamp securing the part to be welded through a combination of forge pressure and lateral loads. The clamp has friction elements at the interface of either the lateral clamp and/or the backstop and the part to be welded.

Abstract: An aerofoil typically for a blade or vane for a gas turbine engine comprises a pressure wall and a suction wall, at least one of the pressure and suction walls comprise corrugations and a coolant hole on an inner surface, the corrugations define a downstream surface and the coolant hole having an inlet defined in the downstream surface.

Abstract: The present invention provides a method of detecting shaft break in a shaft system comprising a shaft coupled between two masses. The method comprises a number of steps. Firstly, to define a time-dependent rotational speed equation for the shaft in terms of system inertia for an engine transient event. Then to discretize the rotational speed equation in terms of a discrete time constant in the discrete domain. Then to recursively define the discretized equation to give a recursive equation and to solve the recursive equation to determine the discrete time constant. Then to define a threshold as a function of engine power and then to set a shaft break signal to TRUE if the discrete time constant is greater than the threshold. A shaft break detection system is also provided by the present invention.

Abstract: An aircraft (10) comprises a wing (12) having a trailing edge (34), a suction surface (14) and a pressure surface (16). The aircraft (10) further comprises a propulsor device (22) having a first inlet (24) and an outlet (30) defined by a passageway. The first inlet (24) is located so as to ingest boundary layer air (56) adjacent the suction surface (14), and the outlet (30). The outlet (30) is located downstream of the trailing edge (34) of the wing (12).

Abstract: An apparatus for inspecting a turbomachine includes a plurality of horoscopes, a device to rotate the rotor of the turbomachine and a processor having reference measurements of the rotor blades and/or reference measurements between the rotor blades and the horoscopes. A boroscope is inserted in a casing aperture upstream of the blades to view the leading edge and a portion of one of the surfaces of each blade as the rotor is rotated. A boroscope is inserted in a casing aperture downstream of the blades to view the trailing edge and a portion of one of the surfaces of each blade as the rotor is rotated. The boroscopes supply the images of each of the blades to the processor. The processor analyses the images of the blades and uses the reference measurements to determine the position and size of any defect on any of the rotor blades.

Abstract: A turbomachine casing assembly includes a first casing element locatable radially outward of one or more rotating aerofoil elements of a turbomachine and a second casing element located radially distal to the first casing element, with a void being defined between the first and second casing elements. Each of the first and second casing elements includes, at a first end thereof, respective co-operating first and second interface portions. In the event that an aerofoil element becomes detached from the turbomachine and impacts the first casing element, the second interface portion; slides along the first interface portion and the first end of the first casing element enters the void.

Abstract: The seal arrangement is arranged between the casing portions and a fluoropolymer O-ring seal is positioned between the casing portions. A first protecting member is positioned between the fluoropolymer O-ring seal and the casing portion and the first protecting member consists of a polymer and hydroxyapatite. The first protecting member consists of 50 to 80 wt % polymer and 20 to 50 wt % hydroxyapatite and incidental impurities. The first protecting member is located in an annular groove and is thus arranged between the casing portion and the fluoropolymer O-ring seal. The first protecting member is substantially U-shaped in cross-section and the fluoropolymer O-ring seal is positioned between the legs of the U-shaped cross-section first protecting member. The first protecting member prevents corrosion of the casing portion by the fluoropolymer O-ring seal.