Patent RU-2622682-C1 (RU)
Inventor: ESKIN IZOLD DAVIDOVICH
IPC: F04D29/38
Filed: 2016-05-18
Granted: 2017-06-19
Abstract: FIELD: machine engineering. 
     SUBSTANCE: proposed hollow wide-chord fan blade, consisting of a shell made of a sheet of a titanium alloy, and rigidly connected with it the power carrier elements: one made of a titanium alloy, and others, made of unidirectional fiber metal matrix material of high composite modulus. Wherein n+1 force bearing elements are made in the form of "swallowtail" locks and are placed between the other n power of bearing elements and the edges of the blade lock, n-1 power of carrier elements, made of composite material, have a locking portion formed as a "swallowtail", and disposed within the shell portion in the form of a rod with a constant or gradually narrows towards the end of the blade quadrangular cross-section, with the sides, in contact with, repeating its shape shell. All the bearing elements are fixed to each other by the lock parts by means of diffusion welding at the temperature and pressure, and parts located inside the shell - are connected with the shell. Power bearing element of a titanium alloy has a U-shape in a side view of a blade formed by the crossbar and the uprights, with a locking part formed in the shape and size of "swallowtail" of blade lock. The damper is fixed in its cavity between racks. Between the end of the damper bar and the actuator, there is a configured gap selected at the maximum operating temperature. Between the bearing surfaces and damper struts with interference red-hot steel, polished smooth tapes are installed. The damper is designed as a multilayer multispan girder collected from m≥10 polished red-hot steel belts, assembled in layout m=m 1 +2m 2 +2m 3 +2: in the center of the package is installed m 1 =1, 2, and smoother tapes, they both sides "to the top of the corrugation peak of the corrugation" package has two raised "corrugations in corrugated" of m 2 =1, 2 or more corrugated strips, on which are mounted packages from m 3 =1, 2, and smoother tapes, mounted outside the package are smooth belts, one on each side of the package, with a thickness   h n =(k/2)⋅h, where k=2÷10 and h - the thickness of the inner damper tapes measured in mm. These tapes with a pitch equal to two steps flutes, which are symmetrical to the longitudinal axis of the belt are made rectangular protrusions, wherein the protrusions of one ribbon are shifted to step corrugations relative protrusions of another outer band and the middle of the projections are arranged in sections where the vertices of the corrugations are located, resting on the smooth belts packets packages installed outside the corrugated strips. In the assembled damper corrugations fully extended elastically by bending protrusions on the smooth exterior tape portion and lugs bent to the outer tape support surfaces and they are dampers themselves. The locking parts of power racks and the carrier element in the package is a hole into which the pin is press-fitted. Friction surfaces of the packet and smooth steel belts, on which it relies, are covered with wear-resistant coating. The very wide-hollow blade is manufactured according to the below-offered method. A method of manufacturing a hollow of wide fan blade, consisting in the fact that a sheet of titanium alloy made shell hollow of wide blades the desired shape of the fan and sizes, obtained power carrier elements: n+1 power carrier element constructed as a castle "swallowtail" blade and n-1 power carrying member having a locking part formed as a "swallowtail" blade, and a portion in the form of a rod with a constant or gradually narrowing the end rectangular transverse blade nym section preformed monolayers of metal matrix material of high composite modulus - boron fibers in an aluminium matrix, or boron fibers coated with silicon carbide in an aluminium matrix, carbon fibers in an aluminium matrix, or fibers of silicon carbide in a titanium matrix. They are exposed to stage thermal-processing, with a gradual increase in its exposure to the material. Moreover, preferably in the first stage, the impact of thermal-processing is 40-70%, in the second step the degree of thermal deformation effects processing with simultaneous shaping to the desired bearing elements geometric shape is 60-90% and the final processing of thermal deformation of these elements carrying up to 100% in the composition is carried fully assembled workpiece while pressing and diffusion welding of the blade. Another force supporting element is produced from the titanium alloy, and it has a U-shape in the side of the blade formed by the crossbar and the uprights, with a locking part formed in the shape and size of "swallowtail" blade lock. The red-hot steel damper is collected from polished coated tapes of wear-resistant coating, in the arrangement of m=m 1 +2m 2 +2m 3 +2, it is compressed to the full package resilient straightening of the corrugations, while bending back the outer band of each protrusions packet to the other outer band package. The package is ground over the projections. The bearing elements are placed in a shell in a manner and at a distance from each other in accordance with reinforcement diagram is inserted into the cavity of the force bearing element made of titanium alloy without a gap technological insert of refractory material and set the strength element with an insert into the shell at its place in the blade. The so formed workpiece is stack into the die, which repeats the profile of the blade size. As part of the assembled block, the final stage of thermal-processing carrier elements is operated, while pressing and diffusion bonding of the blade at a predetermined temperature and pressure. After removing the die blade from the carrier and insert from the actuator, and while the blade is not cooled, roasted ground smooth belts are inserted to the cavity and damper force bearing element. Moreover, the desired amount of interference on the bearing surfaces of the damper provides the selection of the thickness of the smooth belts. 
     EFFECT: high strength and static stiffness of huge light hollow of wide blades GTD fan conserved or accruing in the course of a work cycle, with a highly damping device capable not only to reduce the dynamic stress in the blade during impact and vibrations to a safe level, but also to improve the resource and reliability of GTD fan. 
     2 cl, 6 dwg