Abstract: A head part of an annular combustion chamber for a gas turbine, the head part comprising: an end wall with a passage opening for accommodating a burner, the end wall comprising a back side which faces towards the combustion chamber; a burner collar adapted to fit within the passage opening and receive the burner, the burner collar comprising a protruding portion radially protruding from an outer surface of the burner collar; and a ring member for receiving the protruding portion of the burner collar; wherein the head part of the annular combustion chamber is configured such that in an installed configuration a radially outer portion of the ring member engages with the end wall and a radially inner portion of the ring member receives the protruding portion of the burner collar.

Abstract: A heat treatment apparatus 10 for heat treating metals or metallic components includes a fluidised bed furnace 20 and a removable insert 30 which is accommodated within the fluidised bed 50 of the furnace 20. The removable insert 30 enables the geometry of the fluidised bed 50 to be optimised with respect to the size and shape of a component 70 which is to be heated.

Abstract: A head part (100) of an annular combustion chamber for a gas turbine, the head part comprising: an end wall (110) with a first opening (112) for accommodating a burner; a heat shield (120) covering a back side of the end wall which faces towards the combustion chamber, the heat shield comprising a second opening (124) for accommodating the burner; and a burner collar (130) adapted to fit within the second opening and receive the burner; wherein the head part of the annular combustion chamber is configured such that in an installed configuration the burner collar is fastened to the heat shield with one or more first fasteners (142) to form a sub assembly (140) and the heat shield of the sub assembly is fastened to the end wall with one or more second fasteners (144).

Abstract: A head part of an annular combustion chamber for a gas turbine, the head part comprising: an end wall with a passage opening for accommodating a burner, the end wall comprising a back side which faces towards the combustion chamber; a burner collar adapted to fit within the passage opening and receive the burner, the burner collar comprising a protruding portion radially protruding from an outer surface of the burner collar; and a ring member for receiving the protruding portion of the burner collar; wherein the head part of the annular combustion chamber is configured such that in an installed configuration a radially outer portion of the ring member engages with the end wall and a radially inner portion of the ring member receives the protruding portion of the burner collar.

Abstract: In a method of manufacturing an article (28) by diffusion bonding and superplastic forming stop off material (122) is applied to prevent diffusion bonding in a predetermined pattern on a first surface (106) of a first metal workpiece (100) and the predetermined pattern is spaced from the edges of the first surface (106) of the first metal workpiece (100). Stop off material (124) to prevent diffusion bonding is applied in a predetermined position on the first surface (106) of the first metal workpiece (100) and the predetermined position extends from the predetermined pattern of stop of material (122) on the first surface (106) of the first metal workpiece (100) towards one edge of the first surface (106) of the first metal workpiece (100).

Abstract: In a method of manufacturing an article (28) by diffusion bonding and superplastic forming stop off material (122) is applied to prevent diffusion bonding in a predetermined pattern on a first surface (106) of a first metal workpiece (100) and the predetermined pattern is spaced from the edges of the first surface (106) of the first metal workpiece (100). Stop off material (124) to prevent diffusion bonding is applied in a predetermined position on the first surface (106) of the first metal workpiece (100) and the predetermined position extends from the predetermined pattern of stop of material (122) on the first surface (106) of the first metal workpiece (100) towards one edge of the first surface (106) of the first metal workpiece (100).

Abstract: A guide vane 100 is provided in which sheet portions 14, 15 are secured together to define an aerofoil profile 11. Between ends 20, 21 of the guide vane 100 there is a non linear variation in the maximum chordal thickness 13. Thus, greater maximum chordal thickness 13b in central portions of the guide vane 100 provide stiffness while ends 20, 21 which are generally formed from solid material have a smaller maximum chordal thickness such that a stiffer vane 100 can be provided with reduced material weight and therefore costs.

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 welding torch (10) comprises an electrode (12), means to supply weld filler material (14), a nozzle (16) surrounding the electrode (12), means to supply inert gas (17) to the nozzle (16) and a shroud (18) surrounding the nozzle (16). There are means to form a seal (20) provided between the nozzle (16) and the shroud (18), the means to form a seal (20) is arranged to allow relative movement between the nozzle (16) and the shroud (18). The means to form a seal (20) comprises a plurality of rings (22,24,26). Each ring (22,24,26) has an aperture (28,30,32) and an outer diameter (34,36,38). The diameter of the aperture (28) in a first ring (22) is substantially the same as the diameter of the nozzle (16). The outer diameter (34) of the first ring (22) is less than the outer diameter (36) of a second ring (24). The outer diameter (36) of the second ring (24) is substantially the same as the diameter of the shroud (18).

Abstract: A gas turbine engine (10) fan outlet guide vane (34) is manufactured by diffusion bonding titanium alloy sheet metal workpieces (52, 54) together to form an in integral structure (66). A titanium alloy is weld deposited at predetermined positions (70, 72) and in a predetermined shape to build up bosses (42, 44) at the radially outer end (40) of the hollow integral structure (68). The integral structure (66) is inflated at high temperature to form a hollow integral structure (68) of predetermined aerofoil shape. Apertures (46, 48) are drilled through the bosses (42, 44) to enable the radially outer end (40) of the fan outlet guide vane (34) to be attached to a fan casing (32) of the gas turbine engine (10).

Abstract: A welding torch (10) comprises an electrode (12), means to supply weld filler material (14), a nozzle (16) surrounding the electrode (12), means to supply inert gas (17) to the nozzle (16) and a shroud (18) surrounding the nozzle (16). There are means to form a seal (20) provided between the nozzle (16) and the shroud (18), the means to form a seal (20) is arranged to allow relative movement between the nozzle (16) and the shroud (18). The means to form a seal (20) comprises a plurality of rings (22,24,26). Each ring (22,24,26) has an aperture (28,30,32) and an outer diameter (34,36,38). The diameter of the aperture (28) in a first ring (22) is substantially the same as the diameter of the nozzle (16). The outer diameter (34) of the first ring (22) is less than the outer diameter (36) of a second ring (24). The outer diameter (36) of the second ring (24) is substantially the same as the diameter of the shroud (18).

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 gas turbine engine (10) fan outlet guide vane (34) is manufactured by diffusion bonding titanium alloy sheet metal workpieces (52,54) together to form an in integral structure (66). A titanium alloy is weld deposited at predetermined positions (70,72) and in a predetermined shape to build up bosses (42,44) at the radially outer end (40) of the hollow integral structure (68). The integral structure (66) is inflated at high temperature to form a hollow integral structure (68) of predetermined aerofoil shape. Apertures (46,48) are drilled through the bosses (42,44) to enable the radially outer end (40) of the fan outlet guide vane (34) to be attached to a fan casing (32) of the gas turbine engine (10).

Abstract: A method of diffusion bonding at least two metal workpieces (12, 14, 16) comprises assembling the workpieces (12, 14, 16) into a stack (10) relative to each other so that the surfaces (18, 20, 22, 24) are in mating contact. The edges of the workpieces (12, 14, 16) are sealed together, except for an aperture (42) where a pipe (44) is to be inserted. A pipe (44) is joined to the stack (10) such that the axis (50) of the pipe (44) is arranged at an angle of at least 45° to the axis (48) of the aperture (42) to provide a sealed assembly. The interior of the sealed assembly is evacuated via the pipe (44) and the pipe (44) is sealed. Sufficient heat and pressure is applied across the thickness of the workpieces (10, 12, 14) to diffusion bond the workpieces together to form an integral structure. The angling of the pipe (44) relative to the aperture (42) reduces the possibility of the pipe (44) being sucked back and bursting during diffusion bonding.