Abstract: An annular platform for the nozzle of a low-pressure turbine in a turbomachine, said nozzle having a longitudinal axis and comprising at least one fixed vane disposed downstream from at least one moving blade of a high-pressure turbine, said platform comprising a downstream portion supporting said fixed vane radially defining an aerodynamic channel which extends longitudinally between a leading edge of said fixed vane and a trailing edge of said moving blade, said platform further comprising an upstream portion extending longitudinally beyond the leading edge of said fixed vane towards the trailing edge of said moving blade so as to lengthen said aerodynamic channel.

Abstract: The invention provides a method of fabricating a turbine stator casing, the method comprising the operations consisting in: between the walls of portions of a mold, forming a cavity of shape corresponding to the shape of the shroud of said casing, securing soluble cores to at least one of said mold portions, said cores being held at a distance from the wall of said mold portion and representing empty spaces that are to be formed inside said shroud; putting soluble inserts into place between the cores to represent flow paths between said empty spaces; filling said cavity with a metal alloy powder; sintering said powder by hot isostatic pressing; eliminating the cores and the inserts by dissolving them; and extracting the shroud as molded in this way. The invention is applicable to fabricating a turbine stator casing for an airplane turbojet.

Abstract: A device for assembling together annular flanges by means of fastening bolts, in particular in a low-pressure turbine stage of the turbojet, one of the flanges has an element projecting from its face that faces the other flange and that is received in a notch in said other flange when the relative angular positioning of the two flanges is correct.

Abstract: A turbomachine comprising at least a first rotary assembly with a first shaft, a stator, and bearings secured to the stator and suitable for supporting said shaft, one of said bearings being capable of giving way when an unbalance occurs in the rotary assembly, at least one segment of said shaft being covered in a covering which comprises at least one piece of fabric impregnated with resin and which is for coming into contact with a surrounding portion of the turbomachine when said unbalance occurs in order to protect the first shaft and ensure that there is no risk of said first shaft rupturing. The turbomachine is intended to be used mainly in the field of aviation, and more particularly as an airplane turbojet.

Abstract: A turbine stator casing comprising a jacket and fastener hooks for fastening a turbine distributor nozzle, the hooks projecting from the inside face of the jacket, said jacket being made of a first alloy by hot isostatic compression using metal powder, said fastener hooks being made out of a second alloy that is more refractory than the first, and being secured to said jacket by diffusion welding during the hot isostatic compression. The casing also comprises inserts passing through the fastener hooks and through said jacket. These inserts, which are likewise secured to the jacket by diffusion welding, serve during manufacture of the casing to fasten the hooks to a mold portion inside which the jacket is formed. The invention is applicable to the turbines of airplane turbojets.

Abstract: A turbomachine comprising at least a first rotary assembly with a first shaft, a stator, and bearings secured to the stator and suitable for supporting the first shaft, one of said bearings being capable of giving way when an unbalance occurs in the first rotary assembly. The turbomachine further comprising brake means for braking the first shaft when the unbalance occurs, and bond means acting at the end of braking to bond a portion of the first shaft to a surrounding portion of the turbomachine. The turbomachine is intended to be used mainly in the field of aviation, and more particularly as an airplane turbojet.

Abstract: A device for balancing a rotating part, in particular a turbine rotor in a turbomachine such as a turbojet or the like, the device comprising at least one balance weight comprising engagement means for engaging it on an annular flange of the part, and locking means associated with the balance weight and with the annular flange to prevent the balance weight from moving relative to the annular flange and to block itself against moving both in rotation and in axial translation relative to the balance weight.

Abstract: A turbine blade including a head at its peripherally outer end, and on the outside face thereof at least one wiper is formed having a first end portion and a second end portion, with a wiper tip extending between the two end portions. The first portion situated on the suction side of the blade is taller than the second end portion to form a sawtooth effect between the wipers of two adjacent blades mounted on a turbine rotor. The tip of each wiper presents a convex surface between the first portion and the second portion.

Abstract: A connection device between a nozzle and a feed enclosure for feeding cooling fluid to at least one injector in a turbomachine, the device comprises at least one bushing having open axial ends engaged in orifices in a wall of the nozzle and in a wall of the feed enclosure, together with retaining means for retaining the bushing axially, the retaining means being formed to project from an outer cylindrical surface of the bushing between the axial ends of the bushing and at a distance from said ends.

Abstract: An attachment device for attaching a blade to a turbine rotor disk in a turbomachine, the blade root forming a male portion engaged and held radially in a cavity of complementary shape in the rotor disk, with means for preventing the blade root from moving axially in the cavity, the blade axis being inclined relative to a perpendicular to the axis of rotation of the rotor, in a direction and at an angle that are designed to compensate at least in part for the displacement of the axis of the blade caused by the mechanical and thermal stresses applied to the rotor during operation of the turbomachine.

Abstract: Distributor sectors (25) on which fixed vanes are placed adjacent to a casing (31) by means of sealing sectors (32) alternating with them in the axial direction and provided with force resistant faces (37; 39) through which forces exerted on the distributor sectors are transmitted to the casing. The inner surface of the casing (31) is smoother and is not fitted with any hooks; consequently, this casing (31) is less complicated to make and is less mechanically stressed to retain the distributor sectors, and the distributor sectors may be installed by a purely axial movement.

Abstract: The present invention concerns a cooled gas turbine blade comprising a foundry part and a longitudinal sleeve obtained by the forming of metal sheet, the foundry part including a longitudinal body provided with a longitudinal cavity with first and second apertures at its ends, the sleeve being mounted in the cavity being held therein by soldering or brazing to the wall of the first aperture, and an end portion of which is free to slide in the second slide-forming aperture. The blade is characterized by the fact that the end portion and the slide are in sliding contact relatively to surfaces formed by machining.

Abstract: For the or each moving wheel of the turbine, blade inserts are used each comprising at least two blades interconnected by common outer and inner platforms and sharing a common root. Inserts are used having hollow roots in which respective recesses are formed, and the roots of inserts belonging to the same wheel and/or the roots of inserts belonging to two different wheels are voluntarily given different configurations in the inserts of the roots so as to adjust the resonant frequencies of said inserts to values that are significantly different, thereby ensuring that the inserts in the same wheel and/or between two different wheels are out of tune. The invention is applicable to turbines both for aviation and for industrial applications.

Abstract: An assembly of turbine distributor sectors in a casing. Retaining hooks of a flange of straightening sectors, bearing fixed blades in a turbomachine, are advantageously placed on an end plate distinct from the casing but assembled on the casing. In this way, these hooks no longer constitute weak points in the casing, as if they were all in one piece with it, assembly of the sectors is facilitated, and the assembly is more rigid.

Abstract: An annular platform for the nozzle of a low-pressure turbine in a turbomachine, said nozzle having a longitudinal axis and comprising at least one fixed vane disposed downstream from at least one moving blade of a high-pressure turbine, said platform comprising a downstream portion supporting said fixed vane radially defining an aerodynamic channel which extends longitudinally between a leading edge of said fixed vane and a trailing edge of said moving blade, said platform further comprising an upstream portion extending longitudinally beyond the leading edge of said fixed vane towards the trailing edge of said moving blade so as to lengthen said aerodynamic channel.

Abstract: A cooling device for cooling disks of high-pressure and low-pressure turbines of a turbomachine, said device being fed with cooling air from at least one air orifice formed through a bottom annular platform for supporting at least one fixed vane of said low-pressure turbine and being disposed between an upstream flange and a downstream flange of said bottom platform, the device comprising: an upstream annular plate extending radially from the upstream flange of said bottom platform; a downstream annular plate extending radially from the downstream flange of the bottom platform, said upstream and downstream plates longitudinally defining at least one annular cavity for cooling air; a sealing device extending longitudinally between said upstream and downstream plates so as to close the cooling air cavity in leaktight manner; holding means for holding said upstream and downstream plates against the upstream and downstream flanges of said bottom platform; and a plurality of holes for injecting cooling air towards

Abstract: The turbine blade has a head (6) at its peripherally outer end, and on the outside face thereof there is formed at least one wiper (12) having a first end portion (16) and a second end portion (20), with a wiper tip (26) extending between the two end portions. The first portion (16) situated on the suction side of the blade is taller than the second end portion (20) so as to form a sawtooth effect between the wipers (12) of two adjacent blades mounted on a turbine rotor. The tip (26) of each wiper presents a convex surface between the first portion (16) and the second portion (20).

Abstract: A device for centering a tube component positioned inside and rotationally secured at its end to a turbine hollow shaft positioned in a gas turbine engine. The device includes a sheath enclosing and solidly joined to the tube component, and an elastic ring interposed between the sheath and the shaft. The ring includes a plurality of pairs of opposed shoes extending radially outwardly therefrom and configured to radially expand so as to extend against an inner portion of the shaft. The shoes include thin, elastic cylindrical walls having an external diameter configured slightly less than the internal diameter of the shaft prior to assembly onto the shaft, and arranged to expand to the inner wall of the shaft when assembled thereon.

Abstract: Distributor sectors (25) on which fixed vanes are placed adjacent to a casing (31) by means of sealing sectors (32) alternating with them in the axial direction and provided with force resistant faces (37; 39) through which forces exerted on the distributor sectors are transmitted to the casing. The inner surface of the casing (31) is smoother and is not fitted with any hooks; consequently, this casing (31) is less complicated to make and is less mechanically stressed to retain the distributor sectors, and the distributor sectors may be installed by a purely axial movement.

Abstract: The housing is heated or cooled to adjust its diameter and, in particular, the play between the tips of the rotor blades and the housing. The apparatus consists of networks of tubes (1) covering complementary portions of the circumference of the housing and consisting of a pair of distributors (3) and parallel tubes (2) between said distributors, said tubes (2) being alternately connected to one or other of the distributors and provided with apertures to blow the gas onto the housing. The counter-flow circulation in the tubes (2) makes it possible to supply both gas that has been greatly heated by traveling a considerable distance through the tubes (2) and cooler gas that has traveled less far in other tubes (2) to any point on the housing, thereby balancing out the heat applied to every portion of the housing.