Abstract: A turbine engine blade made from a composite material and having at a free end thereof an integrated brush joint. A process for producing such a blade includes the steps of:introducing a fibrous fabric into a mold,introducing specific fibres into the mold, in the vicinity of the free end of the blade,injecting a resin into the mold,performing polymerization by use of a heating press of the resin-impregnated fibrous fabric.

Abstract: An engineered ceramic component for the leading edge of a rotor blade provides enhanced erosion protection therefor. In one embodiment, the engineered ceramic component includes a strain isolator member, an aerodynamic ceramic member, a first adhesive bond layer, and a second adhesive bond layer. The strain isolator member, which is operative to minimize strain transfer between the rotor blade infrastructure and the aerodynamic ceramic member, is configured so that inner mold line surface thereof is complementary to outer mold line surface of the rotor blade infrastructure. The aerodynamic ceramic member, which is operative to provide enhanced erosion protection for the respective leading edge of the rotor blade, is configured so that the outer mold line surface thereof defines the aerodynamic configuration of the respective leading edge and the inner mold line surface is complementary to the outer mold line surface of the strain isolator member.

Abstract: A coating for protection of airfoil surfaces from erosion caused by the impingement of particles in the incoming air stream of a gas turbine engine or on helicopter blades. The coating consists of an epoxy film toughened with hard particles to improve the erosion resistance and softer particles which impede the progression of cracks through the coating. A method for applying the coating is also described.

Abstract: A method and apparatus for increasing blade fatigue strength in a turbine engine. The blades in the turbine engine are configured so as to reduce stress at the tip of the blades during operation of the turbine engine, thus increasing blade fatigue strength. This stress reduction helps to counteract the detrimental effect of abrasive tip coatings on blade fatigue strength. In one embodiment, the tip of the blade is chamfered in order to reduce the stress on the tip of the blade. An abrasive coating is then applied to the tip of the blade to assist the blade in seating into an abradable outer air seal. In another embodiment, an abrasive coating is applied to a center portion of the tip of the blade, with the periphery of the abrasive coating being set back from the opposing surfaces of the blade.

Abstract: A plastic propeller for marine electric trolling motors modified to prevent the entanglement and build-up of weeds by the application to its surface of a thin sheet of metal formed in the shape and size of the blade and extending beyond the blade's leading edge.

Abstract: Methods for improving the erosion resistance of composite airfoils are disclosed as are the resultant structures. Wire mesh materials are coated with an erosion-resistant coating, formed to the shape of the airfoil leading edge, and molded into the leading edge during airfoil fabrication.

Abstract: A pump assembly includes a motor having a rotatable motor shaft, and a pump housing having a housing wall with an exterior side and an interior side. Within the pump housing is an impeller which is mounted on the shaft for rotation in unison therewith, and which is free to slide axially along the shaft. A first coupler is rotatably mounted on the shaft outside the housing wall and a second coupler is attached to the impeller. The first and second couplers are retentively and movably engaged and are adapted to cooperate with one another so that they will cause the impeller to move axially on the shaft to a desired position.

Abstract: The present invention provides a composite airfoil particularly useful as a fan blade, having a high degree of twist, in a large high bypass ratio turbofan engine. The composite airfoil of the present invention has a progression of filament reinforced airfoil laminations of varying span, arranged in order by span, and interrupted by at least one filament reinforced airfoil lamination having a span out of height order to form what is called a confused or broken shear plane where radially outer tips of the laminations end.

Abstract: A high efficiency exhauster which is capable of attaining operating efficiencies of up to 70% when employed in a solid fuel pulverizer firing system that includes a pulverizer which is operative to effect the pulverization therewithin of the solid fuel supplied thereto and a furnace into which the pulverized solid fuel is injected for combustion therewithin. The high efficiency exhauster includes a casing, an inlet ring supported on the casing, a rotor mounted on the casing for rotation therewithin, a multiplicity of blades, each of a preestablished length and width, mounted in spaced relation one to another on the circumference of the rotor so as to extend at a preestablished angle, and an outlet formed in the casing.

Abstract: An abrasive system and a processing procedure is provided which permits the direct installation of a thick abrasive blade tip cap onto a cast turbine rotor blade during a heating schedule which requires two furnace operations. The composition of the abrasive blade tip cap advantageously utilizes the high temperature performance capabilities of equiaxed or single crystal rotor blade alloys without significantly affecting their mechanical properties as a consequence of the processing necessary to permanently bond the abrasive blade tip cap to the rotor blade. A semi-rigid mat consisting of the preferred abrasive composition is first consolidated in a first vacuum furnace operation. Blade tip cap preforms are then cut from the mat and positioned on the tip of the rotor blade. The preform and rotor blade are then heated in a vacuum furnace according to a temperature schedule entailing heating rates, holding temperatures and durations which are sufficient to bond the preform to the rotor blade.

Abstract: A vane for the turbine section of a gas turbine has an airfoil portion with leading edge, center and trailing edge portions. The leading edge portion is attached to the center portion by a dove tail joint that allows the leading edge portion to slide in the radial direction with respect to the center portion while preventing movement in the axial and circumferential directions, thereby eliminating thermal stresses created by differential thermal expansion between the leading edge portion and the remainder of the vane. An opening in the vane inner shroud that is normally sealed by a closure plate allows the leading edge portion to be readily replaced in the event of damage. The leading edge portion may be formed from a ceramic material and need not be supplied with cooling air.

Abstract: A variable pitch propeller blade system includes a conductive clevis attached to a rotor, a mating non-conductive clevis fastened to a non-conductive propeller blade, a pin journaling through bores in each clevis, joining the clevises to form a hinge joint, and a conductive path along a substantial part of the propeller blade.

Abstract: A process of manufacturing a steam turbine bucket having water droplet erosion resistance including the steps of:a) forming a bucket (10) of a first steel alloy having a blade portion (12), the blade portion having a leading edge (14) and a trailing edge (16);b) welding an insert (18) of a second steel alloy to the leading edge (14) of the bucket;c) heat treating the bucket (10) and insert (18);d) finish machining the bucket (10) and insert (18); andd) hardening the insert (18) to impart water droplet erosion resistance to the insert.

Abstract: A system for protecting against erosion the surface of a body which is subjected to an airflow and consists essentially of a fibrous material or a fiber-reinforced plastic material, such as a rotor blade, has a metallic coating which, in the respective area to be protected, covers the surface in several layers. The primary layer of the coating consists of aluminum or a similar material with a modulus of elasticity that is approximately identical to that of the material on the surface of the body. The primary layer, in the form of a sheet glued to the surface, is coated with a two-phase material, in which particles of metallic oxide and/or metallic carbide and/or metallic nitride compounds are embedded in a finely distributed manner in a ductile, solid-solution-hardened matrix of a metallic but non-ferrous material.

Abstract: A composite axial flow rotary machine blade (50) and method of blade construction is disclosed. A partial-length, spanwisely-disposed hollow spar (20) partially captures a shaped foam core (30) which extends from within the spar's cavity (26) along a substantial length of the blade (50) in a spanwise fashion. A resin-impregnated high strength, high modulus cloth (34) and graphite (32) composition overlays the spar-core assembly (36) and forms the casing (50) with airfoil regions (52, 54) of the propeller blade (10). This construction results in a rotor blade (50) with enhanced natural frequencies thereby providing for an enhanced operational speed range.

Abstract: A component is provided with a relative undersize in an area to be subjected to increased stress, for instance, through temperature. The component is made of a hardenable steel. The undersize is overlaid with a non-hardenable steel thereby to provide the full size. A second layer on top of the first layer can be provided. When the second layer is metallurgically bonded in a manner that generates heat, it does not cause a heat affected zone in the base hardenable steel. Blades for steam turbines benefit from this procedure.

Abstract: A composite fan blade comprises a blade portion (12) formed from a first set of unidirectional layers of fibers (110) wrapped around a wedge shape bushing (16). A blade platform (14) comprising a second set of unidirectional fiber layers (114) filled with a resin filler (116) is pressure molded with the blade (12) and bushing (16) to form a desired blade shape. The blade is then hinge mounted to a metallic blade support disk (18). The blade of the present invention provides a strong, lightweight fan blade for small, high speed propfan turbine engines.

Abstract: A hollow core fan blade for a gas turbine engine, having a continuous leading edge, is fabricated using a four-sheet superplastic forming/diffusion bonding process which results in a cost-efficient and lightweight, yet strong, structure. The rotor blade is comprised of a face sheet which has a 180 degree bend therein so that the two face sheet ends are aligned. Bonded to opposing sides of the face sheet are first and second core sheets, between which is the hollow core. To fabricate the blade, a core sheet assembly is inserted inside the prepared face sheet, thereby forming a Ti-Pack (titanium pack) assembly having a plurality of pressure-tight cells. The Ti-Pack is inserted into a cavity within a die, after which the rotor blade, having predetermined design characteristics, is superplastically formed by heating the die and selectively pressurizing the plurality of cells.

Abstract: A method of manufacturing a lightweight composite propulsor blade of spar and shell construction comprises forming a composite spar (30) having an elongated foam body (20) bonded to a short metal retention tulip (10) and overlayed with a dry braided wrap of angular structural fibers and substantially unidirectional spanwisely aligned structural fiber plies disposed between the braided layers; adding a leading edge foam body (42) and a trailing edge foam body (44) to the spar assembly to form a blade subassembly (50); providing a dry braided fabric wrap over the blade assembly; disposing the fabric covered blade subassembly into a shell molding die and simultaneously impregnating the dry spar fabric wrap and the dry shell fabric wrap with a curable resin material; and curing the impregnated blade subassembly.

Abstract: A protection element containing a spring steel strip is bent to have a greater curvature than the curvature at the leading edge of a fan blade. This protection element is then fixed to the leading edge of the fan blade over an area of maximum erosion. Rubber or another elastomer can be extruded over the strip before or after it is fixed to the fan blade or the strip can incorporate an outer hardened layer to resist erosion. Attachment of the strip to the blade is advantageously accomplished using rivets or screws at spaced locations along the blade and at the leading edge of the blade.

Abstract: A gas turbine bucket and a gas turbine nozzle applied with a ceramic coating comprises a base material of the bucket and the nozzle made of a heat resisting alloy; a plurality of coating layers for the front portion consisting of, a mixture layer which comprises a ceramic material and metal and which is formed on the base material, an alloy layer which comprises an alloy material exhibiting excellent resistance to high temperature oxidation and corrosion and which is formed on the mixture layer, and a ceramic layer which comprises ceramic material and formed on the alloy layer. Such ceramic coating has a satisfactory thermal barrier effect on the base material of the gas turbine bucket and nozzle.

Abstract: A steam turbine blade is provided having a trailing edge portion formed from an erosion resistant material deposited on the blade airfoil by a friction surfacing method. According to the method, a rotating consumable rod of erosion resistant material is placed in contact under axial load against a bonding surface formed on the airfoil, thereby causing a portion of the rod adjacent the bonding surface to be plasticized. The rod then traverses the surface linearly leaving in its wake a layer of erosion resistant material bonded to the airfoil by a high quality metallurgical bond. The layer is then ground to form the smooth contour desired for the trailing edge.

Abstract: A propeller system is formed on a shaft by at least one pair of axially spaced propeller blades each having a first and a second blade section extending at a selected acute (or obtuse) angle to the axis of the shaft, the first sections and second sections respectively of the pair of propeller blades are substantially parallel to each other and the tips of the first sections of each of the blades are connected to the tips of the second section of each of the blades respectively to form a box shape. The shaft is connected to the propeller system in a manner so that the axis of the shaft extends substantially diagonally of the box shape whereby the parallel sections of the blades move in opposite directions relative to the fluid in which they are contained when the shaft is rotated to facilitate improvement of the efficiency of the propeller system.

Abstract: The internal blade damper is an elongated member with a damping surface of discrete width in contact with the interior blade surfaces. Contact is continuous throughout a substantial length. The damper extends between 2.degree. and 30.degree. from the radial direction, producing a direction of contact having some radial component. Centrifugal force loads the damping surface.

Abstract: A protection element containing a spring steel strip is bent to have a greater curvature than the curvature at the leading edge of a fan blade. This protection element is then fixed to the leading edge of the fan blade over an area of maximum erosion. Rubber or another elastomer can be extruded over the strip before or after it is fixed to the fan blade or the strip can incorporate an outer hardened layer to resist erosion. Attachment of the strip to the blade is advantageously accomplished using rivets or screws at spaced locations along the blade and at the leading edge of the blade.

Abstract: A hybrid metal/composite spinner cone used in aircraft applications. The spinner cone has a metal outer shell which is bonded during the molding process to an inner structural member of thermoplastic composite. The metal shell imparts several desirable characteristics to the spinner cone such as impact resistance, erosion resistance, appearance, and supplying a lightning strike material to protect the composite structure. The thermoplastic composite has significant property advantages over metal or thermoset systems. The hybrid metal/composite spinner cone is manufactured using a ceramic mold which is less expensive and more readily available than a steel mold. The metal shell provides a barrier between the thermoplastic composite and the ceramic mold and allows the finished spinner cone to be easily released from the mold.

Abstract: A rotor and a method for the production thereof which incorporates the inently strong, highly damped, yet light weight characteristics of fiber reinforced plastic composites, Achieving with a minimal amount of added weight in the form of high density material a significant reduction in the vibratory response of the rotor due to hydrodynamic flow excitation, by selectively tailoring the mass distribution therein as by adding the high density material at selected locations of the rotor.

Abstract: An elongated, flexible protective urethane member is bonded and firmly affixed to the leading edge of a glass fiber reinforced polyester skin fan blade for large diameter industrial water cooling tower fans. The polyester blade without such protective member would be subject to leading edge abrasion and deterioration during use. The flexible protective member is applied to the blade prior to curing of the chemically thickened polyester skin. Firm bonding and adherence of the protective member to the leading edge of the blade skin is obtained by curing of the skin with the protective member in place over the leading edge of the blade.

Abstract: This invention is directed to a high damping and damage tolerant flexible opeller assembly and a method for the production thereof. The high damping and damage tolerant flexible propeller has a unitary hub having an axis of rotation and adapted for mounting on a rotatable shaft, multiple spokes extending from the hub portion, each spoke at its tip portion being made of a high density material having the shape that conforms to that of the specific propeller, each spoke at its inner portion from the tip portion to the hub portion being made of multidimensional fibers, the inner portion of each spoke being made of a multidimensional fiber preform being impregnated with a highly viscoelastic matrix material.

Abstract: This invention relates to abrasive layers for use in the gas turbine industry. The preferred embodiment of the invention comprises nickel coated, yttria doped silicon nitride particulates dispersed within a nickel base superalloy matrix which is substantially free of oxides. The layer is formed using low pressure plasma spray processes.

Abstract: In an aircraft propeller which can change in pitch, each propeller blade is mounted upon a hinge, which reduces the effective stiffness of each blade. The angle of the hinge pin can be constructed such that the angle between torsional and flexural nodes is favorable.

Abstract: A method and apparatus for forming a hardened contact surface on a shroud of a turbomachinery blade comprising casting the blade and internal shroud with a metal insert into the casting mold so that the blade is cast with the insert in place. The insert may be formed with a projection extending from a wear surface of the shroud into the plane of the blade shroud such that the material from which the blade is made is cast about the projection to firmly and mechanically hold the insert in place. Each insert is preferably formed of a relatively low coefficient of friction and high wear resistant material whereby contact between abutting inserts on adjacent shroud surfaces have a high degree of slippage.

Abstract: In a hydraulic screw pump, a sealing element for the peripheral edge of the rotary screw. The sealing element is formed with a channel along its length to fit over this edge of the rotary screw. The channel may be varied in depth to adjust the gap between the rotary screw and a water-carrying trough for the pump. The width of the channel may also be adjusted to accommodate rotary screws of varying thicknesses. The sealing element, thus, retains the desired width of the gap even though the edges of the rotary screw are chipped or worn away.

Abstract: The normally multi-part gas turbine engine labyrinth seal outer portion which carries an abradable lining, is formed from a single piece and has a groove machined in its periphery for the receipt of the feet of respective stator vanes. Pins are fitted in pairs through the walls of the groove to provide lateral location for the feet. The pins and a groove liner are made from an anti-frettage material.

Abstract: A composite gas turbine engine blade is made by braiding a plurality of fibers to form a preform having an airfoil precursor portion and an integral root precursor portion. A plurality of fiber shaping inserts are positioned in the root precursor portion, either by braiding the root precursor portion around the inserts or inserting the fiber shaping inserts into the root precursor portion after braiding, to impart an enlarged, divergent shape (e.g., dovetail precursor shape) to the braided root precursor portion. The braided preform with the enlarged, shaped root precursor portion is infiltrated with matrix material and shaped to near net shape to provide the composite blade with a dovetail shaped root.

Abstract: A fan impeller comprises a back plate, a front plate and a plurality of blades lying between the front and back plates, wherein the blades are fitted relative to the axis of rotation of the impeller to provide a leading edge adjacent the back plate, so as to impart, in use, a lateral sideways vector to a stream of and passing along the blades. At least two of the blades may be of increased thickness than the remaining blades. These improvements increase the life of the fan impeller significantly.

Abstract: A method of manufacturing or repairing a turbine blade which includes removing a part of a blade such as a damaged part and securing thereto an insert of hard steel which has been hardened prior to securing to the turbine blade and is then welded to the turbine blade temporarily and heat treatment processes may be carried out and it is desired that the insert is hardened to a hardness greater than that eventually required since such hardness may be reduced during the securing of the insert to the turbine blade.

Abstract: A braided gas turbine engine blade preform includes an airfoil precursor portion and an integral root precursor portion. A plurality of fiber shaping inserts are disposed in the root precursor portion, to impart an enlarged, divergent shape (e.g., dovetail precursor shape) to the braided root precursor portion. The braided preform with the enlarged, shaped root precursor portion is infiltrated with matrix material and shaped to near net shape to provide a composite blade with a dovetail shaped root.

Abstract: In an axial-flow fan, a motor support, a frame having a cylindrical inner surface, a boss fixed to the drive shaft and having a cylindrical outer surface, and blades radially extending from the cylindrical outer surface of the boss is provided legs for connecting the frame and motor support, and are also provided with surfaces inclined with respect to the direction of the air stream to reduce resistance to air flow. In another embodiment, the downstream end of the air duct defined by the cylindrical inner surface of the frame is gradually expanded toward the direction in which air is blown out. In a further embodiment, the upstream end of the boss has cut-away portions for enlarging the area of the cross section for air flow.

Abstract: A method of repairing turbine blades where it is required to repair a blade while it is in situ on a rotor involves the movement of a lacing wire out of engagement with the blade to be repaired so that the blade may be repaired. The lacing wire may be completely removed from the array and replaced, or a new lacing wire member inseted by providing elongate holes or slots in the blade to enable the lacing wire member or members to be inserted into the blade array.

Abstract: A propeller blade of fiber-reinforced plastic with a combined erosion, icing and lightning protection system has a metal shroud fitted to its leading edge, the shroud enclosing a cavity and accommodating a heating conductor at its interior. A ground line of the heating conductor is connected to ground and serves as a lightning conductor.

Abstract: A fan blade protection system (100) is provided for substantially preventing erosion by particulate impingement on the fan blade. Fan blade protection system (100) includes an outer erosion resistant layer (110) laminately bonded to an elastomeric energy dissipative layer (120). The laminate structure of fan blade protection system (100) is bonded to a portion (12) of fan blade (10). The outer erosion resistant layer (110) is formed of a material having a high yield strength such that it elastically deforms on impact by high velocity particulates. The energy transferred to the outer erosion resistant layer (110) is absorbed and distributed by the elastomeric energy dissipative layer (120), minimizing the force transmitted to the surface of the fan blade.

Abstract: A blade of a compressor rotor has its tip provided with at least one discontinuous sealing lip formed by two half lips arranged on opposite sides of the blade asymmetrically with respect to a transverse sectional plane of the blade tip, either with or without overlap of the half lips in the direction of the chord of the blade.

Abstract: A method of repairing a turbine blade of the type having one or more lacing wire holes comprising the steps of welding additional metal to the blade, subjecting the blade to a stress relieving heat treatment process before which the or each lacing wire hole is effectively eliminated by filling the hole or holes with material the same as or at least compatible with the material from which the blade is made. The turbine blade may be subjected to the application of mechanical forces to restore its form and machining to restore its shape can be gauged to ensure both its form and shape is correct.

Abstract: A part and method for repairing a high velocity fluid flow machine part, for example a turbine blade comprises an insert which may be made from a piece of material the same as the turbine blade and prior to attachment to the blade has an edge region hardened by any suitable means, for example induction hardening, the insert then being secured to the blade by welding or brazing, the weld or braze material being of a relatively soft nature to provide a cushion between the insert and the blade so as to minimize the occurrence of stress corrosion cracking.

Abstract: The portion of the blade (1) to be coated has pure vanadium powder deposited thereon and the temperature of the powder is raised to a temperature which is slightly higher than the melting point of vanadium. Thereafter, a powder mixture is deposited on the vanadium layer, said powder comprising about one third by weight of titanium carbides, titanium nitrides, or titanium borides, which are bonded by a martensitic or austenomartensitic stainless steel. The powder is then raised to a temperature which is greater than its melting temperature and less than the melting temperature of vanadium. A titanium alloy blade it includes, on its periphery, a coating layer (5) which is at least 1 mm thick and which includes about one third by weight titanium carbides, or titanium nitrides, or titanium borides bonded by a martensitic or austenomartensitic stainless steel, said coating layer covering an under layer (6) of vanadium having a thickness lying between 0.5 mm and 1.5 mm.

Abstract: The worn tip of a turbine blade is restored by applying a metallurgically bonded wear resistant surface at the tip. The wear resistant surface is applied using a transferred plasma arc and powdered metal particles.

Abstract: A protective tip (5) for a titanium steam-turbine blade (1), comprises 28% to 40% TiC, 12% to 26% Cr+Co, 1% to 6% Mo, 3% to 8% Ni 0.3% to 1.5% Cu and a balance of Fe. The tip (5) is brazed to the blade (1) by interposing a copper-based strip (6) having a thickness lying between 7/100 mm and 15/100 mm therebetween, then raising the temperature of the blade (1) and its tip (5) to between 900.degree. C. and 950.degree. C. in a vacuum or inert atmosphere oven. This temperature is maintained for a period of between thirty minutes and seventy-five minutes, and the oven is allowed to cool to ambient temperature. Optimal brazing also serves to harden the tip (5) possesses very good resistance to abrasion by water droplets.

Abstract: A propeller blade is insulated to withstand the high temperature exhaust of a gas turbine engine. The blade has a spar, a skin covering the spar and forming a contour of the blade, and an insulating layer disposed between the spar and the skin along the portion of the blade operating within the high temperature exhaust of an engine.

Abstract: A propulsor blade for an aircraft engine includes an airfoil section formed in the shape of a scimitar. A metallic blade spar is interposed between opposed surfaces of the blade and is bonded to the surfaces to establish structural integrity of the blade. The metallic blade spar includes a root end allowing attachment of the blade to the engine.