Abstract: A method of welding a first component and a second component together, the method comprising: controlling movement of a first component and/or a second component to form a joint, the first component and the second component defining a first side and a second side; controlling welding of the first component and the second component on the second side using filler to form a seal weld to seal the joint; controlling provision of a vacuum chamber to enclose the joint within a volume; controlling evacuation of the volume defined by the vacuum chamber; and controlling power beam welding of the joint, the power beam being provided from the first side and through the evacuated volume.

Abstract: A method of determining a fuel delivery fault in a gas turbine engine is provided, the engine having a combustor, a combustor fuel system for delivering fuel to the combustor, and a turbine which is driven by hot gas from the combustor. The method includes comparing a measured turbine gas temperature profile against a predicted turbine gas temperature profile. The method further includes comparing a measured fuel delivery flow number of the combustor fuel system against a predicted fuel delivery flow number of the combustor fuel system. The method further includes indicating that a fuel delivery fault in the combustor fuel system has been detected when both the measured turbine gas temperature profile and the measured fuel delivery flow number differ from their predicted values by more than respective predetermined thresholds.

Abstract: A gas turbine engine has a core engine including: a compressor, combustion equipment which receives compressed air from the compressor, a circumferential row of nozzle guide vanes, and a turbine. The nozzle guide vanes defines a throat receiving hot working gases from the combustion equipment into the turbine. The gas turbine engine further has an air system which is switchably operable between an on-position which opens a diversion pathway along which a portion of the compressed air exiting the compressor bypasses the combustion equipment to join the hot working gases at re-entry holes located between the nozzle guide vanes and a rotor at the front of the turbine, thereby increasing the semi-dimensional mass flow ?(T30)0.5/(P30) of the core engine at the exit of the compressor, and an off-position which closes the diversion pathway, thereby decreasing the semi-dimensional mass flow of the core engine at the exit of the compressor.

Abstract: A method of producing a curved plate by additive layer manufacture is provided. The method includes building up the plate layer-by-layer such that a first layer forms a bottom edge of the plate and the plate is additively extended upwards therefrom by subsequent layers such that a last layer forms an opposing top edge of the plate. In this way, spaced, first and second lateral edges of the plate each grow layer-by-layer to extend between respective ends of the bottom and top edges. The plate thus built up arches over from the bottom edge to adopt a curved shape on cross-sections through the plate normal to the bottom edge.

Abstract: A method of determining a fuel delivery fault in a gas turbine engine is provided, the engine having a combustor, a combustor fuel system for delivering fuel to the combustor, and a turbine which is driven by hot gas from the combustor. The method includes comparing a measured turbine gas temperature profile against a predicted turbine gas temperature profile. The method further includes comparing a measured combustor instability against a predicted combustor instability. The method further includes indicating that a fuel delivery fault in the combustor fuel system has been detected when both the measured turbine gas temperature profile and the measured combustor instability differ from their predicted values by more than respective predetermined thresholds.

Abstract: A fluidic device for providing analogue output control includes a main channel, a first control channel, a second control channel, a comparator which receives respective input fluid flows from the main, the first and the second control channels. The first control channel is configured such that the input fluid flow therefrom carries an oscillating pressure wave signal, the second control channel includes a flow regulator controllable to vary the mass flow rate of the input fluid flow from the second control channel, and the main channel is configured such that the input fluid flow therefrom is at a reference mass flow rate. The comparator is configured such that the input fluid flows from the first control and the second control channels act in combination on the input fluid flow from the main channel to produce an output fluid flow from the comparator having a PWM mass flow rate characteristic.

Abstract: A fuel injector system with a fuel feed arm extending inwardly from an outer casing of combustion equipment of a gas turbine engine to a flame tube of the equipment, which ends in an injection nozzle which penetrates a head of the tube to deliver fuel. The system has a swirler arranged coaxially with the nozzle at the head of the tube, including one or more circuits which produce flows of swirling air around the fuel. A seal ring seals the nozzle to the swirler, the nozzle being removably inserted into the ring. The ring has a flange portion, and the swirler has a pair of spaced retention grooves at a front face thereof. Opposite edges of the flange portion slidingly locate in the grooves so it sealingly engages to the front face. The swirler has a spring mechanism which retains the flange portion in the grooves.

Abstract: This invention concerns improvements in the inspection, assessment and re-working of manufactured components such as nozzle guide vanes (NGVs) and blades, in particular by improving the comparison of the component with nominal data. Dimensional data of a physical component is obtained and used to create a virtual digitized model of the component which is aligned with a nominal CAD model of the component in a virtual space. The correspondence is assessed and used to adjust weightings of different regions of the digitized model to improve the alignment. This process is repeated within the digital space until either conformance is reached or it is determined that this is not possible.

Abstract: The present invention provides a support duct for a gas turbine engine. The supported duct comprises at least one support frame having an aperture defined by an upper aperture wall, a lower aperture wall and opposing aperture side walls. It further comprises a duct extending through aperture, the duct comprising an upper panel in abutment with the upper aperture wall, a lower panel in abutment with the lower aperture wall and opposing side walls extending between the upper and lower panels. The opposing side walls of the duct are spaced from the opposing aperture side walls.

Abstract: A ducted fan gas turbine engine has a propulsive fan, a fan case surrounding the fan, a core engine, and a plurality of support structures which transmit loads from the core engine to the fan case. Each support structure has two support struts which extend from the core engine to a joint radially outwardly of the fan case. The support struts are spaced apart at the core engine but converge to meet at the joint. Each support structure further has two structural elements which extend from the joint to respective fixing positions on the fan case at opposite sides of the joint.

Abstract: A combustion chamber comprises an upstream end wall, at least one fuel injector and at least one seal. Each fuel injector is arranged in a corresponding aperture in the wall. Each seal is arranged in a one of the apertures in the wall and around one of the fuel injectors. Each seal has a first portion, a second portion and a third portion. The second portion abuts the corresponding fuel injector. Each seal has a plurality of circumferentially spaced coolant passages extending longitudinally there-through from the upstream end to the downstream end of the seal to provide internal convective cooling of the seal to improve the working life of the seal.

Abstract: The present disclosure concerns the detection of ice within a system. More specifically, but not exclusively, the disclosure concerns the detection of ice accretion within a gas turbine engine. The apparatus and method relies on heating a first region (38) of a component (44) and comparing the measured temperature of the first region (38) with a second temperature value, possibly measured at a distinct second region (40) of the component (44).

Abstract: A unison ring assembly for a gas turbine engine has a unison ring and a plurality of levers extending from the unison ring. Each lever has a pin at one end that inserts through a bore of a respective bush mounted in the unison ring. Each bush is formed as separate first and second parts which are mounted to their through-hole by inserting the first part into the through-hole from one side of the unison ring and the second part into the through-hole from the opposing side of the unison ring. Each part has a respective stop which prevents that part from inserting into the through-hole by more than a predetermined amount. When both parts are inserted by their predetermined amounts, their ends join together to form the bush and prevent the parts being retracted from the through-hole.

Abstract: There is disclosed an apparatus for use in an electroetching or electrodeposition process in which material is etched from or deposited onto the surface of an electrically conductive component. The apparatus comprises a support for supporting the component within a tank containing an electrolytic solution; and a first-polarity electrode arranged to be located within the tank and immersed in the electrolytic solution and shaped to surround at least a part of the component in a contactless manner. In use, an electric field produced by the first-polarity electrode results in an electric variance between at least a part of the component and a second-polarity electrode having a polarity opposite to that of the first-polarity electrode. An electroetching and an electrodeposition process are also disclosed.

Abstract: A device (10) for a current limiter is described, the device (10) comprising: at least one coil assembly (12) adapted to carry a current, the coil assembly (12) comprising: a first coil (14), comprising a first superconducting element, adapted to carry a first portion of said current, and a second coil (16), comprising a second superconducting element, adapted to carry a second portion of said current, wherein said first and second coils (14, 16) are arranged such that, when said first and second superconducting elements are each in a superconducting state and said coil assembly (12) carries said current, a magnetic field generated by said first portion of said current in said first coil (14) is substantially cancelled by a magnetic field generated by said second portion of said current in said second coil (16); and wherein said device is adapted such that, in use, the first superconducting element carries a higher proportion of said current than the second superconducting element.

Abstract: Method for casting a turbine component body including; providing a mould defining the external geometry of the component body and providing a core defining an internal geometry of the component body. The core includes a main body defining an internal chamber of the component body and an array of pedestals extending between opposing walls of the internal chamber. A molten material is cast between the mould and the core and the core is then removed after the molten material has solidified. The core is provided using a core die which has an inlet for receiving fluid core material. The core die is configured such as to provide a gradient of injection pressure which decreases from a first position proximal to the inlet to a second position distal to the inlet. The pedestal array is arranged such that the separation of the pedestals increases between the first and second positions.

Abstract: A tool for machining splines on a workpiece comprises a base, a first tooth extending radially from the base and a second tooth extending radially from the base. The second tooth is spaced circumferentially from the first tooth. The first tooth has a first height, the second tooth has a second height and the second height is less than the first height. The first tooth tapers from the base to the tip of the first tooth, the second tooth tapers from the base to the tip of the second tooth and the first tooth is identical to the second tooth to the second height.

Abstract: A method for the manufacture of a cylindrical component suited to use in a high temperature environment and incorporating an erosion resistant coating (4) on its outer cylindrical surface (6) is described. The method comprises, in sequential steps; providing a work piece (1) having a cylindrical body including a pair of axially spaced radially extending ribs (3a, 3b) defining an annular trough (2) therebetween. Shot peening the work piece (1). Applying an erosion resistant coating (4) in the annular trough (2) to a depth which sits radially inwardly of the radially outermost ends of the ribs (3a, 3b). Turning the radially outermost ends of the ribs (3a, 3b) whereby to match the depth of the coating (4) and provide an outer cylindrical surface with a consistent diameter across both ribs (3a, 3b) and the coating (4).

Abstract: The present invention provides a method of designing a manufacturing geometry for a tip portion of a rotary blade for a gas turbine engine. The method comprises first devising a theoretical hot running geometry of the tip portion at a specified design condition. Next, the theoretical operational forces acting on the theoretical hot running geometry at the specified design condition are calculated e.g. using CFD software. Then, the manufacturing geometry is determined (e.g. using FEA analysis) using the calculated theoretical operational forces.

Abstract: A gear pump has first and second meshing gears for pumping a fluid. The gear pump further has a first electrical motor having a first rotor, a first stator and first coil windings. The gear pump further has a second electrical motor having a second rotor, a second stator and second coil windings. The first rotor is operatively connected to the first gear and the second rotor is operatively connected to the second gear such that each gear is rotated by its respective rotor. The first and second coil windings are energized by respective and separate first and second electrical power circuits such that the first and second meshing gears can be driven independently of each other.