Abstract: This invention provides a segmented annular seal (10) the sealing leakage gaps between relatively movable components 14,16 between high and low pressure regions in a gas turbine engine, for example for sealing an engine shaft 16. The seal comprises an annular array of circumferentially spaced and radially movable arcuate seal segments (12) which extend in a continuous end to end relationship in annular housing (14) and project radially from the housing for effecting a seal against an engine shaft (16), rotor or the like. The segments (12) are located in a channel (22) in the housing (14) sized such that the segments (12) are able to follow radial movements of the shaft (16). In order to reduce an axial loading on the segments (12) that ends to cause them to seize a pressure balance region (30) vented to the upstream pressure region is formed on the downstream side of the segments (12).

Abstract: A combined linear and rotary actuator has a shaft with a screw thread, a nut engaging the screw thread and engaging means movable between a first location where rotation of the turning mechanism produces substantially linear displacement of the shaft, and a second location where rotation of the turning mechanism produces substantially rotary displacement of the shaft. The linear actuator finds particular use on retractable marine propulsor such as used on submarines and the like.

Abstract: An apparatus (10) for bulge testing an article (12) comprises a pressure vessel (14) arranged to define a chamber (15), the pressure vessel (14) has a first aperture (28) and a second aperture (30), means to pressurize the chamber (15), means (19) to measure the deflection of the article (12, means (39) to measure the pressure in the pressure vessel (14) and means (18) to determine material properties of the article (12) using the measurements of pressure in the pressure vessel (12) and the measurements of deflection of the article (12). A piston (24) is arranged to move within the pressure vessel (14) and the chamber (15) is filled with a fluid. The means to pressurise the pressure vessel (14) comprises a gun (16) arranged to fire a projectile (36) to strike the piston (24) to produce a high pressure in the fluid in the chamber (15) in the pressure vessel (14) to deform an article (12) placed over the first aperture (28) in the pressure vessel (14) to seal the pressure vessel (14).

Abstract: A method of making an aerofoil blisk (10) comprising a plurality of aerofoil blades (12) joined to a disc (14) to extend radially outwardly therefrom includes the step of forming a blade member (28) having a stub (30) for joining to the disc (14), the stub (30) having a taper ratio of less than 2. The stub (30) of the blade member (28) may be joined to the disc (14) by linear friction welding, and excess material may subsequently be machined from the blade member (28) to form the blade (12).

Abstract: The present invention is a method of monitoring the health of a fuel system 30 of a gas turbine engine 10. The fuel system 30 comprising a fuel-metering valve 36, a hydraulic control valve servo pressure line 40 and a control pressure line 39. The fuel-metering valve comprises a hydraulic control valve solenoid 36 for metering the flow of fuel and a fuel filter 38 and, in use, a current is applied to the solenoid 38 to control the required fuel demand to fuel nozzles 25. The method comprises the steps of; measuring either the percentage difference between fuel metering valve demand and actual positions or the percentage difference in pressure between the servo pressure line 40 and the control pressure line 39, comparing the differential to a predetermined level, when that predetermined level is reached a warning is given. Thereby the engine may be scheduled for service before unsatisfactory performance of the fuel system is experienced.

Abstract: A phosphate bonded ceramic is used to provide a protective coating on a rare earth-transition metal (RE-TM) alloy substrate, conferring degradation resistance to the alloy by being oxidation resistant and acting as a diffusion barrier, thereby minimising/preventing oxygen diffusion and elemental depletion. The alloy substrate may, for example, be a permanent magnetic alloy component and may be used in aerospace applications.

Abstract: It is necessary to support components while machining is performed. In such circumstances work supports are now provided, whilst previously there was a dedicated arrangement for each component to be supported. By achieving a modularity in terms of adjustment through creating mountings comprising rings, arcs or bars secured upon posts a rigidity of presentation of support ends is achieved. By providing spacers for location about the posts on the mountings variability with regard to the positioning of the support ends is achieved such that similar geometry but different sized components and articles can be supported by the support arrangements. Furthermore, the spacers may be readily removed if C shaped, and the rings, arcs or bars can be shifted.

Abstract: A method of manufacturing a fan blade (26) for a gas turbine engine by powder metallurgy comprises the steps of forming a container (52) and placing at least one metal insert (52) at a predetermined position within the container (52) and filling the container (52) with metal powder (60). The at least one metal insert (62) has a predetermined pattern of stop off material (68,70) on at least one surface of the metal insert (64,66). The container (52) is evacuated and then sealed. The container (52) is hot pressed to consolidate the metal powder (60) into a consolidated metal powder preform (72). The container (52) is removed from the consolidated metal powder preform (72). The consolidated metal powder preform (72) is heated and a fluid is supplied to the predetermined pattern of stop off material (68,70) to hot form at least a portion of the consolidated metal powder preform (72) to form the hollow metal fan blade (26).

Abstract: The present invention relates to a cooling arrangement in which a fractal passage network is provided incorporating several passage stages. Each passage stage 4, 5, 6, 7 has substantially the same passage cross-section for consistency with other passage stages to facilitate flow pressure control across the fractal passage network. Normally, the length of passages in each passage stage are also specifically determined in order to achieve a consistent flow pressure control. The arrangement is particularly utilized with regard to cooling within turbine engine components such as blade aerofoils.

Abstract: A combustor component with cooling apertures has the apertures formed by laser drilling. The machining apparatus comprises a beam generator for generating a beam for directing at the combustor component and a beam trap. The component is translated relative to the beam and the beam is directed to the beam trap and is dissipated within the beam trap.

Abstract: A gas turbine engine has a nacelle, a plurality of pipes and a drains assembly, the drains assembly including a drains mast that extends through the nacelle and provides an outlet for the pipes. The engine is characterised in that drains assembly has a connection block defining internal passages and is arranged to connect between the pipes and the drains mast. The connection block also has lateral connections to the pipes enabling the nacelle to have a lower profile; thereby reducing aerodynamic drag.

Abstract: In a turbofan gas turbine engine, a fan shaft is rotatably mounted and radially supported by a bearing in a bearing support structure supported from a fixed engine structure by radially frangible bolts and radially extending spokes. The radially inner ends of the radially extending spokes are mounted on a common member that engages the bearing support structure. The radially outer ends of the radially extending spokes are mounted on a fixed engine structure located radially outwardly of the bearing support structure. The radially extending spokes are held in tension and include a super elastic material to exert a radially inward restoring force on the bearing support structure, subsequent to any radial excursion of at least part of the fan shaft relative to an engine rotational axis (X) following any fracture of the frangible bolts.

Abstract: Acoustic noise from relatively high pressure gas flows as a result of opening for example a bypass valve in a gas turbine engine can cause problems. By provision of an acoustic apparatus incorporating an inner chamber where there is a pressure reduction and then a chamber divider surface incorporating small apertures with a wide spacing distribution an upward shift in acoustic frequency of the gas flow is achieved beyond normal human comprehension. An outer chamber is provided to receive the fine gas flow jets from the apertures in the chamber divider surface for further pressure reduction and low pressure release through wider apertures in an exit surface.

Abstract: A blade for a turbomachine extends in use, in a radial direction relative to the axis of the turbomachine. The turbomachine has at least one operating condition which generates supersonic fluid flow at the blade. The blade is adapted to provide, at the supersonic operating condition, a leading edge sweep angle which varies such that successive radial positions (i) to (iii) along the leading edge are at respective sweep angle turning points. Position (i) is the radially inner and position (iii) the radially outer of the positions. Position (i) is at or radially outward of the 30% span position, where 0% span is the radially innermost point of the leading edge and 100% span is the radially outermost point of the leading edge.

Abstract: When capacity coupling between an output gate electrode (OG) and a last-stage transfer electrode is large at an output end of a CCD shift register, an electric potential of the OG is varied according to transfer clocks with the result that noise is liable to generate in an output signal. As measures for this, convex portions projecting horizontally are formed in those positions of the last-stage transfer electrode and the OG, which correspond to a channel region, and overlap between the electrodes is caused only on the convex portions. A clearance is formed between the OG and the transfer electrode except those locations, in which the convex portions are provided. In that location, in which the OG and the transfer electrode, respectively, are extended relatively lengthily toward wirings, the electrodes do not overlap each other. In this manner, capacity coupling between the electrodes is reduced.

Abstract: A marker paint comprises 42 wt % to 52 wt % pigment, 31 wt % to 37 wt % acrylic resin and 17 wt % to 21 wt % silicone resin excluding solvent. The pigment comprises cobalt titanium oxide, titanium nickel antimony oxide, cobalt aluminium oxide or cadmium sulphide selenium to give a green, yellow, blue or red color respectively. The marker paint is used in conjunction with an irreversible temperature indicating paint to determine if there is any debris and/or dirt on the irreversible temperature indicating paint to affect the accuracy of the temperature measurement of the irreversible temperature indicating paint.

Abstract: Engine control systems utilize a number of potential control loop regimes optimized for particular engine conditions. These loops may relate to transient conditions or engine steady state. The choice of engine control loop is made by a selector by the error divergence between measured signals and reference signals. These reference signals generate adjustment demands for the engine. It is possible for the nature of the selector to select the steady state control loop prior to acquisition of the desired target performance criteria. The steady state control loop will take longer to achieve the optimum performance conditions. The present invention provides for a multiplier, such as squaring of the error divergence, in order to retain authority for the transient control loop control beyond the normal selector determined error divergence criteria.

Abstract: A gas turbine engine rotor blade containment assembly (38) comprising a generally cylindrical, or frustoconical, casing (40). The casing (40) having at least one member (54) and the member (54) has a first portion (53) extending radially from the casing (40) and a second portion (55) extending axially from the first portion (53) of the member (54). At least one cassette (80) being provided and one or more liner panels (74) being arranged in each cassette (80). A first end (84) of each cassette (80) being locatable on the second portion (55) of the member (54) and the first end (84) of each cassette (80) being shaped to correspond to the shape of the first and second portions (53,55) of the at least one member (54) to protect the first and second portions (53,55) of the at least one member (54). The second end (86) of each cassette (80) having at least one axially extending member (96) removably securable to the casing (40).

Abstract: A surface treatment device for applying a surface treatment medium to an article is provided with the surface treatment device having an application member for applying the surface treatment medium to the article and an electrode, which applies an electrical potential between the application member and the article. The device provides localised treatment to the article and can remove oxide layers or the like from metallic materials without removing or damaging the underlying metallic material.

Abstract: A turbine blade comprising a pressure wall and a suction wall joined together at leading and trailing edges and having a root portion and a blade tip region, the walls further define a hollow chamber and through which cooling air is directed in use from the root portion to the blade tip region only, characterised in that at least one of the walls defines at least one cooling rib that extends outwardly from the wall into the chamber and at least a portion of the rib tapers between the root portion and a blade tip region.