Abstract: A forming die (10) comprises a first die part (12) and a second die part (14). The first die part (12) has a first shaped forming surface (16) and the second die part (14) has a second shaped forming surface (18). The first die (12) has a number of pillars (28,30,32,34). Two of the pillars (28,34) are arranged at a first side of the first die (12) and two of the pillars (30,32) are arranged at a second opposite side of the first die (12). The second die (14) has a number of pillars (44,46,48,50). Two of the pillars (44,50) are arranged at the first side of the second die (14) and two of the pillars (46,48) are arranged at the second opposite side of the second die (14). The pillars (28,30,32,34) on the first die (12) are locatable on the pillars (44,46,48,50) on the second die (14). The pillars (28,30,32,34) on the first die (12) and the second die (44,46,48,50) have interlocking means (28B,30B,32B,34B, 44B,46B,48B,50B) to prevent relative movement between the first die (12) and the second die (14).

Abstract: A welding torch (10) for welding on a component has an electrode (12) within a nozzle (14) through which a flow of gas passes. A shield (20) defines an enclosure (22) around the nozzle (14). Means are provided for supplying weld filler material (18) into the vicinity of the electrode (12) through the shield (20). One end of the shield (20) is attached to the welding torch (10). The other end of the shield (20) is open and extends towards the component (16). An inflatable seal (28) is mounted on the end of the shield (20) to seal between the shield (20) and the component (16).

Abstract: A method and apparatus for improving the properties of a material of a workpiece by laser shock peening in which an overlay which is opaque to a laser beam, and an overlay which is translucent to said laser beam, are applied to a surface of a workpiece. The translucent overlay being applied on top of and over the opaque overlay. A laser beam is then directed at the said surface to which the overlays have been applied to vaporize the opaque overlay and laser shock peen the surface of the workpiece to produce a region of compressive residual stress in said surface. The overlays and the laser beam being applied concurrently, in a single operation, as the surface of the workpiece is traversed so that as each point on the surface to be treated is traversed the opaque overlay, translucent overlay, and laser shock peening are applied sequentially to that point. The opaque overlay is preferably an ink layer which is applied by printing on the surface.

Abstract: A seal structure (10) has a flange (12) which locates against the flange of another member (22) and is held there by a “U” shaped clip (32). Member (22) has one or more cut outs (30) in its flange, and clip (32) has a corresponding number of tags (34) formed in one leg of its “U” shape. The or each tag (34) is bent inwards. On assembly, the flange of member (22) is placed against flange (12) and clip (32) is pushed over the sub assembly until the tag(s) (34) locate in a respective cut out (30). The need for drilling holes and riveting or bolting the assembly together is thus obviated.

Abstract: A duct comprising an inner casing spaced apart from an outer casing and which also comprises a number of interfaced duct sections must be assembled in such a way to prevent relative redial movement between the casings and thereby inhibit buckling. The present invention is a duct which utilises abutment members which longitudinally extend from each of the inner walls across the interface of the duct sections. The abutment members are radially spaced apart in normal use but are configured such that substantially relative radial movement of the inner and outer walls is prevented when the overlapping members abut.

Abstract: A seal arrangement, for example a brush seal 8? in a gas turbine engine, includes thermal matching means for matching the rates of response of a supporting ring 14?, 16? of the seal, and of a rotatable component 4 with which the seal cooperates, to thermal changes in the environment of the seal induced by changes in operating conditions. The thermal matching means may comprise a slugging mass 24 and/or thermal insulation 28. Alternatively, or in addition, the region 24 of the housing at which the seal 8? is mounted may be made from a relatively low thermal expansion material. These measures reduce the rate of expansion and contraction of the seal 8? as the temperature in the engine varies so as to match more closely the rate of expansion and contraction of a rotatable component with which the seal cooperates.

Abstract: A power generator comprising: a lifting body for suspension in a moving fluid; a control station; and at least two tethers for tethering the lifting body to the control station. The control station is arranged to transform oscillating tension in the tethers produced by an oscillating movement of the lifting body into mechanical motion.

Abstract: A method of manufacturing a through hole in a component between a first surface and a second surface, the through hole including a cavity formed in the first surface and a communicating passage between the second surface and the cavity including the steps of: a) laser percussion drilling a plurality of blind holes in the first surface to form the cavity and b) drilling a communicating passage between the cavity and the second surface.

Abstract: A gas turbine engine rotor blade containment assembly comprises a generally cylindrical, or frustoconical, stiff containment casing (54), a generally cylindrical, or frustoconical, flexible structure (62) arranged within and spaced radially from the stiff containment casing (54) by crushable structures (64, 66) at axially spaced positions on the flexible structure (62). A viscoelastic material (68) is arranged to fill the space (70) between the stiff containment casing (54), the flexible structure (62) and the crushable structures (64, 66). The viscoelastic material (68) provides local stiffening of the blade containment assembly in the region of a fan blade (34) impact and provides energy dissipation by viscoelastic damping of the flexing of the flexible structure (62) and plastic deformation in the crushing of the crushable structures (64, 66).

Abstract: Rotary apparatus (17) for a gas turbine engine (10) comprises a rotor assembly (63) and first and second stator assemblies (55, 59) mounted coaxially with respect to each other. Each vane (58, 62) has a leading edge and a trailing edge. The stator assemblies (55, 59) are circumferentially translatable relative to each other between a first condition in which each of the vanes (62) of the second stator assembly (59) is substantially aerodynamically aligned with a respective one of the vanes (58) of the first stator assembly (55), and a second condition in which the vanes (58, 62) of the first and second stator assemblies (55, 59) are out of aerodynamic alignment with each other. In the first condition, at least a part of each vane (62) of the second stator assembly (59) extends beyond the trailing edge of the respective vane (58) of the first stator assembly (55).

Abstract: A method for determining the total mass flow through an engine (10) comprises measuring (32) the fuel flow to the engine (10) and measuring the concentration of carbon dioxide in the gases exhausted (22) from the engine (10). The concentration of carbon dioxide is measured by detecting the infrared radiation absorption spectrum of carbon dioxide using a laser (38) and a detector (46). The method comprises determining (48) the air to fuel ratio in the engine (10) from the fuel flow and the concentration of carbon dioxide. The method comprises determining (48) the air mass flow through the engine (10) from the air to fuel ratio and calculating (48) the total air and fuel mass flow through the engine (10) by adding the air mass flow through the engine (10) to the fuel mass flow to the engine (10).

Abstract: A vectorable variable area nozzle is formed by a pair of parallel sidewalls, a pair of opposed clamshell elements arranged between the sidewalls and each able to rotate about an axis perpendicular to the sidewalls and a pair of flaps each pivotally lined to the downstream end of one of the clamshell elements. In use the thrust produced by the nozzle can be vectored by rotating the two clamshells about their respective axes.

Abstract: Forming a hollow structure having an internal coating includes the steps of placing a core shaped to form the internal surface of the structure in a mould, filling the mould with a material powder, hot isostatically pressing the powder about the mould to consolidate the powder, and removing the core from the hollow structure formed, wherein a coating is applied to the core prior to placement in the mould, which coating bonds to the hollow structure formed, during the hot isostatic pressing, to form the internal coating.

Abstract: A method of superplastically forming a workpiece comprises placing the workpiece (16) in a die (14) and heating the workpiece (16) to a temperature at which the workpiece (16) is superplastically formable. Pressure is applied to the workpiece (16) to superplastically form the workpiece (16) to the shape of the die (14). The temperature of the workpiece (16) is measured and is analysed to determine the measured temperature distribution of the workpiece (16) at stages in the superplastic forming process. A database of desired temperature distributions of the workpiece (16) at different stages in the superplastic forming process is kept.

Abstract: A method and device for monitoring the condition of an electrode in an electro-discharge machine, the device comprising an electrode detector operable to produce a position signal indicative of the position of an end region of the electrode in the nose-guide, and a signal processing unit connected to receive a position signal from the electrode detector and operable to determine from the position signal when retraction of the electrode into the nose-guide has occurred, the method comprises monitoring the position of the end region of the electrode and determining when retraction of the electrode has occurred.

Abstract: An engine casing (16) encloses a rotor (15) and has a wall the inner surface (17) of which has slots (20) therein. An abradable lining (19) is attached to the inner surface (17) of the wall and extends across the slots (20). The abradable lining (19) is fluid permeable so that in operation a fluid passes through the lining (19) and recirculates in the slots (20). Recirculation of the fluid within the slots (20) increases the aerodynamic efficiency of the rotor (15).

Abstract: A fan blade assembly (24) comprises a fan rotor (28) and a plurality of radially extending fan blades (30). The periphery (38) of the fan rotor (28) has a plurality of axially extending slots (40). Each of the fan blades (30) has a root portion (42), which locates in one of the slots (40) in the fan rotor (28). Each slot (40) has a slider member (50), which is locatable between the fan blade (30) root portion (42) and the bottom (31) of the slot (40). Each slot (40) has a spring (52), which is locatable between the fan blade (30) root portion (42) and the slider member (50). Each slot (40) has a wedge (54), which is locatable between the slider member (50) and the spring (52).

Abstract: A method for monitoring the health of a system comprises performing at each of a plurality of times the steps of: constructing a condition signature (30) from a plurality of condition indicators including (a) a plurality of vibration measurements acquired from the system or (b) one or more vibration measurements and one or more performance parameter measurements acquired from the system; predicting a normal signature (32) from a model defining one or more inter-dependencies between said condition indicators, the normal signature corresponding to the condition signature for a healthy system; comparing the condition signature with the normal signature; and registering an event if the condition signature differs from the normal signature by more than a predetermined threshold.

Abstract: A method of detecting the change in the structure of a turbine rotor uses the steps of injecting an ultrasonic signal into the turbine rotor at a first position using a first ultrasonic transducer to produce a diffuse field ultrasonic signal in the rotor; detecting the signal in the rotor at a second position using a second ultrasonic transducer measuring the time for the signal to travel from the first ultrasonic transducer to the second ultrasonic transducer and comparing the measured time for the diffuse field ultrasonic signal to travel from the first ultrasonic transducer to the second ultrasonic transducer with a stored time for the diffuse field ultrasonic signal to travel from the first ultrasonic transducer to the second ultrasonic transducer to determine if there is a change in the structure of the turbine rotor.

Abstract: An arrangement 10 for providing thermal energy to a portion 16 of a component 14 of a gas turbine engine while the component 14 is forming, wherein the component 14 is substantially elongate in a first direction 28 and the portion 16 extends from the component 14 in a second direction 38, substantially perpendicular to the first direction 28, and comprises a first surface area component 32 oriented in the first direction 28. The arrangement 10 further comprising an elongate member 18, connected to the portion 16 for heating the portion 16, wherein the elongate member 18 comprises a second surface area component 36, oriented in the second direction 38, wherein the second surface area component 36 of the elongate member 18 is greater than the first surface area component 32 of the portion 16.