Abstract: A catalytic combustion chamber is provided with at least two catalytic combustion zones arranged in flow series. In a first mode of operation fuel is supplied from first fuel injectors, positioned upstream of the first catalytic combustion zone, into the catalytic combustion chamber and is burnt in the first catalytic combustion zone in order to preheat the subsequent catalytic combustion zones. In the second mode of operation the supply of fuel to the first fuel injectors is reduced and fuel is supplied from second fuel injectors positioned between the first catalytic combustion zone and the second catalytic combustion zone into the space between the first catalytic combustion zone and the second catalytic combustion zone. This prevents the first catalytic zone becoming overheated, and reduces the possibility of the second and third catalytic combustion zones becoming overheated and allows the optimum catalyst to be selected for the first catalytic combustion zone.

Abstract: A titanium aluminide based alloy consisting of 42-48 at % aluminium, 2-5 at % niobium, 3-8 at % zirconium, 0-1 at % boron, 0-0.4 at % silicon and the balance, apart from incidental impurities, is titanium. The titanium aluminize alloy composition has a satisfactory combination of high tensile strength, acceptable ductility at room temperature and low secondary creep rate at elevated temperature, so as to be suitable for use in high temperature applications for example aero-engines and automobile engines. It is suitable for compressor discs and compressor blades of aero-engines.

Abstract: In a method for decomposition of hydrocarbons for the production of hydrogen and carbon black, the feed stock is passed through a plasma torch, which causes a pyrolytic decomposition of the feed stock. The feed stock is transported through the plasma torch (A) in a cooled lead-in tube (1) and undergoes a first heating in an area in the immediate vicinity of the plasma flame. The material thereby produced is passed on to one or more subsequent stages where the final and complete decomposition of the hydrocarbons to carbon black and hydrogen occurs. In this area further raw material may be added which causes quenching and reacts with the already produced carbon black. An increase is thereby caused in particle size, density and amount produced without further energy supply, whereafter the products produced are expelled and separated and hot gas may be transported in a return pipe to the torch, in order to further increase the energy yield.

Abstract: In a method for the production of carbon black and hydrogen by means of pyrolysis of hydrocarbons with a plasma torch (3) in a reaction chamber the pressure in the reaction chamber (1), the feed rate for the hydrogen plasma gas and hydrocarbons and the angle of the injection nozzles (2) in the reaction chamber (1) are adjusted in order to establish a reaction zone (5) in the chamber's central area with a location which determines the reaction enthalpy for decomposition of the hydrocarbons into hydrogen and carbon black in order to obtain a desired quality for the carbon part. The enthalpy value is adjusted in a range between 1 and 50 kWh/Nm.sup.3 and the temperature in the reaction zone is maintained between 1000.degree. C. and 4000.degree. C.

Abstract: A sample removing tool comprises two partly spherical blades which are rotatably mounted on a carrier member about parallel axes. The cutting edges of the blades face each other and a portion of the cutting edges are arranged to lie in a nominal circle. The carrier member is rotatably mounted on a support member about an axis, the axis is perpendicular to a plane containing the nominal circle and passes through the center of the nominal circle. The axes of the blades are inclined to the axis of rotation of the carrier member. The blades are rotated about their axes and the carrier member is rotated about its axis such that the cutting edges of the blades move along the circumference of the nominal circle to cut a sample from a surface of a component arranged perpendicular to and intersecting the nominal circle.

Abstract: A method for determining the resonant frequency of vibration of a rotating blade comprises determining the approximate resonance frequency and rotating a blade at a plurality of frequencies in a range above and below the approximate frequency. At each frequency two measurements are taken representative of synchronous amplitudes at each measurement point (P.sub.1 and P.sub.2) wherein the two points are separated by an angle .beta. and there are an unknown number x of complete synchronous vibrations between the two points. A set of data is provided and a plot of P.sub.1 and P.sub.2 produced, the data being analysed to determine a likely value of x and hence the resonant frequency.

Abstract: A combustor for a gas turbine engine has a fuel nozzle located in the upstream end thereof and is positioned within a cylinder coaxial with said nozzle. The cylinder comprises at its downstream end an annular flange extending from the cylinder in a generally radial direction. The flange has a plurality of cooling air apertures radially extending therethrough so as to direct cooling air along the face of an adjacent heatshield.

Abstract: An electrical machine has a rotor shaft (12) which carries a plurality of rotor discs (14) for rotation therewith. Each rotor disc (14) has pairs of rotor rims (16) secured thereto. Each rotor rim (16) consists of a single row of alternate magnets (20) and laminated pole pieces (18) and is opposed by a series of stator cores (22) which straddle the rotor rim (16). Armature windings (24) are disposed within the stator cores (22) for operably exciting said stator. The phase relationship between the currents through the armature windings (24) and the orientation of the stator cores (22) or the magnets (20) in opposing rims (16) are such that the effects of electromagnetic coupling, long path fluxes and torque ripple is reduced.

Abstract: A heat exchanger has been developed with a helical insert (9) permanently mounted in a housing (2). Between the windings in the insert (9) there is formed a helical channel (20) for one heat exchange medium. The insert (9) is designed with a channel (10) for the second heat exchange medium. The heat exchanger is designed with a central tube (13) which is axially movable and rotatable. The central tube (13) is designed with scraper elements for removal of deposits in the channel (20). In one embodiment the scraper element is formed by a helical insert (15) of the same design as the insert (9). The insert (15) is designed with a channel (16) for the second heat exchange medium. In a further embodiment the central tube (13) is designed with one or more scraper arms (23) which may be liquid-cooled. Deposits are often formed on the heat transfer surfaces.

Abstract: A protective eyeglass assembly for use during sport activities comprises a pair of separate lens frames individually cooperating with a lens holder to secure a pair of lenses therebetween. A detachable nose bridge interconnects the pair of separate lens frames with the lens holder so as to form a unitary eyeglass assembly, easily dismountable for lens replacement due to lens damage or lens prescription.

Abstract: A reinforced front part of plastic, for use in the manufacture of cabins or bodies for vehicles in order to achieve rigidity, is molded or shaped as a box-shaped unit in one piece with an enclosure defined by at least five walls which serve as the front, bottom, bonnet, and side walls and with an open side to face the interior of the vehicle.

Abstract: A multiple layer erosion resistant coating on a substrate comprises alternate layers of tungsten and titanium diboride. All of the layers have the same thickness and preferably have thickness's of between 0.3 and 1 micrometer to give improved erosion resistance. The layers are produced by spattering.

Abstract: A bearing assembly supports a shaft. The bearing assembly comprises an outer bearing race and an inner bearing race. Each bearing race has a race track in which a plurality of rolling elements are located. The inner bearing race is split into two halves. The two halves of the split bearing race are interconnected by curvic teeth. The curvic teeth constrain relative movement between the two halves of the split bearing race and maintain concentricity of the bearing race.

Abstract: A bearing support structure for a gas turbine engine comprises an annular array of stator vanes and a radially inner bearing support portion which are interconnected by an annular array of radially extending U-shaped cross-section parts. The U-shaped cross-section parts are interconnected at their radially outer extents and are arranged so that adjacent parts are open in generally opposite axial directions. Such a bearing support structure can carry service pipes with good accessibility and be produced by casting, thereby reducing its cost.

Abstract: When cooling air from a gas turbine engine compressor is supplied in greater quantities than is needed, the flow thereof is reduced firstly and mainly by ensuring that the air leaves a blade stage cooling thereby at a radius less than that of its entry. A pressure head results which slows the cooling air flow rate prior to its entering a plenum chamber defined by the disc of the stage and fixed structure. There is a reduced tendency of the air to enter the gas stream.

Abstract: An optical element is fitted to a high intensity light emitting diode used in a variable message sign. The optical element has surfaces which redirect any stray light from the light emitting diode to form useful light. The faces of the optical element are angled to shape the light beam emitted therefrom. The light beam is shaped by the faces to produce a beam having increased intensity in a predetermined direction. The optical element enhances the visibility of the sign and allows a reduction in the number of light emitting diodes used in the sign.

Abstract: The present invention relates to a process and a device for the separation and purification of gas from a fiber suspension, especially residual gas after ozone delignification or pulp suspension, wherein the suspension together with the gas is introduced into a cyclone (2) or similar in which essential separation of suspension takes place, after which the essentially gas-free suspension is drawn off downwards and the gas (5) containing residual fiber and/or other impurities is drawn off upwards, the gas stream (5), before it is conducted away, being led through a liquid bath for separation of residual fibers and/or other impurities from the gas stream.