Abstract:
A repair coating for superalloy articles, such as gas turbine engine components, includes a volatile organic carrier or water-based carrier, a fluxing agent, a thickening agent, balance a filler mix. The filler mix consists of at least two distinct particulate components. The mix includes a first particulate component having a composition which approximates that of the article being repaired. The mix also includes a second particulate component having a composition approximating that of the article and a melting point depressant, such as boron. This melting point depressant is substantially in excess of that in the article and sufficient to provide melting of a portion of the mix at a processing temperature below the melting temperature of the article. The above filler mix is blended with the other constituents to form the repair coating which is applied to an article.
Abstract:
Apparatus and a method for attaching individual blades to a disc rotor of a BLISK is described. Blade blanks or preforms are gripped between adjustable jaws of a rigid frame member of a linear friction bonding machine, and are attached in a non-rotational friction bonding operation. Blade preforms may be finished to final airfoil shape in a further operation after attachment. The technique is suitable for repair work or original manufacture.
Abstract:
A compressor rotor structure for a gas turbine engine is made by linear friction bonding stub rooted blades and separate platform pieces, to lands between slots in a compressor disc periphery. These results an integral structure in which the periphery of the disc has had metal removed so as to form the slots and the disc is thus lightened, and the stub roots and platform pieces cooperate to form the airflow inner annulus wall.
Abstract:
A mechanism suitable for friction welding aerofoil blades to the periphery of a disc. The mechanism comprises a first member (flywheel 12) which has an ecentric crank pin. Two pivotally interconnected links 18 and 20 are connected between the crank pin and a second member 19 which is pivotally mounted. A blade to be friction welded (by rubbing it in an arcuate path on the disc) is mounted at the point of pivotal connection 32 between the second link 20 and the member 19. An actuator lever 24 is pivotally mounted on a pivot 22 which is located in the vicinity of the locus of movement of the pivotal interconnection 30 between the two links 18, 20. The actuator has a third link 28 which is of the same length as the link 20. The third link is connected by a pivot 26 to the lever 24 at a radius equal to the length of the second and third links 20 and 28. Movement of the lever 24 about its pivot 22 when the pivots 30 and 22 coincide, to bring the pivot 26 into line with the pivot 32 freezes the oscillation of the pivot 32 to enable the blade to be welded to the disc at a precise location along the arcuate path.
Abstract:
Structural components, for example rotor components for a flow-dynamic engine, are first tacked to each other prior to final joining. The tacking is accomplished by a spot resistance welding or a high energy ray welding using a small welding material ball at each welding spot or location. The balls are supplied to a welding spot through a hollow, evacuated electrode of the resistance welding apparatus.
Abstract:
An assembly of stacked rings is provided to form the cylindrical section of a combustor such as used in a gas turbine engine. Each ring is force-fitted into its adjacent ring and joined to it, as by brazing, to form a unitary structure. The rings are configured to assure proper alignment when fitted together and provide a space for holding brazing material immediately adjacent to the mating surfaces to be joined so that the brazing material, when fused in a vacuum furnace, flows evenly between the surfaces. To assure proper distribution of the brazing material when fused, one of the mating surfaces may be upset, as by knurling, to a dimension assuring a light force-fit of the parts to be joined. Each ring also includes a shaped portion projecting into the interior of the assembly for directing cooling air, introduced through the side walls of the rings, along the interior surfaces of the assembly to protect it from high temperature gases generated by combustion of fuel within the combustor.
Abstract:
A T-shape joint includes a slant gap formed between joint faces of a vertical base metal and a horizontal base metal and the slant gap is filled perfectly with a brazing alloy without remaining any defect.The slant gap can be saw tooth shape gaps. The slant gap can be formed in the thickness direction of the vertical base metal.The molten brazing metal penetrates into the slant gap without forming a cavity for a stronger joint.
Abstract:
Disclosed is an electron beam hole drilling process in which the workpiece surface where the hole exits is covered with a backer comprising particulate bonded to itself and the exit surface by a binding agent. The backer enables a hole having substantial uniform symmetry along its length to be drilled and is particularly useful for hollow parts and contoured surfaces. Backers removable by liquifying, melting dissolution, leaching and the like, are particularly useful for inaccessible exit surfaces. In a preferred embodiment the backer is comprised of a nonmetallic particulate such as glass while the binder is a soluble silicate.
Abstract:
An apparatus for connecting metallic parts, and metallic parts so produced, by means of arc fusion welding by producing a low volume welding seam (narrow gap welding), wherein the workpiece parts to be joined and forming a narrow gap are initially welded at their butt joint by means of, for instance, electron-beam welding, plasma-arc welding, laser-beam welding or argon arc-welding to produce a base seam with or without filler material, and thereafter the workpiece flanks forming the narrow gap are united by alternately depositing weld beads at first one and the other workpiece flank by submerged-arc welding.
Abstract:
Using magnetic force upset welding to form T-joints between dissimilar thickness parts. This type of resistance welding is used to join compressor and turbine parts thereby reducing the weight and cost of a jet engine.