Abstract: A turbine damper may be provided that may include an elongated body sized to fit inside a turbine blade, the elongated body elongated along a radial direction of the turbine blade relative to a rotation axis of the turbine blade, and plural dampening masses coupled with the elongated body and disposed at different locations along the radial direction. The plural dampening masses may be one or more of sized to dampen different vibration modes of the turbine blade, or moveable relative to and along the elongated body in the radial direction.

Abstract: A wind turbine blade bushing system for arrangement in a root end of a wind turbine blade is described. The wind turbine blade bushing system comprises a threaded element for retaining a mounting bolt for a wind turbine blade, the threaded element being formed from a first material; and an anchor element for arrangement at the root end of the wind turbine, wherein the anchor element acts to at least partly retain the threaded element in the wind turbine blade, the anchor element being formed from a second material. The first material has a higher strength and higher fracture toughness than the second material.

Abstract: The present disclosure is related to turbine wheel assemblies for gas turbine engines. Such turbine wheel assemblies may include ceramic matrix composite airfoil components mounted with different types of coupling to a central disc.

Abstract: A blade is provided for a gas turbine engine. The blade includes an airfoil portion with at least one internal cavity and a damper located within the internal cavity. The damper includes a cantilever spring arm. A fan blade is provided for a gas turbine engine. The fan blade includes an airfoil portion with at least one internal cavity; and a damper located within the internal cavity. The damper includes a cantilever spring arm that terminates with a rub surface pad adjacent to a friction bridge between a concave pressure side and a convex suction side of the airfoil portion. A method is also provided for damping a blade of a gas turbine engine. The method includes deflecting a cantilever spring arm to contact a rub surface pad with a friction bridge between a concave pressure side and a convex suction side of an airfoil portion of the blade.

Abstract: An impulse element module for a turbomachine, in particular a turbine stage of a gas turbine, preferably an aircraft gas turbine, including a single-unit receptacle component having a base and side walls that extend peripherally thereon, the side walls and the base bounding a receiving space; a single-unit insert component having a form that is inserted into receiving space of receptacle component; together, the receptacle component and the insert component accommodated therein being designed to define a plurality of spaced apart cavities; and an impulse element, in particular a sphere, being accommodated in each cavity; and a single-unit sealing component that is joined in a material-to-material bond to the receptacle component in a way that allows the receiving space to be sealed and the insert component to be surrounded by the receptacle component and the sealing component.

Abstract: Embodiments are disclosed of a turbomachinery component having an outer part that is captured between a cap and a base of the component. In one form, the outer part is placed in compression between the cap and the base. The outer part can be formed prior to being placed between the cap and the base. In some forms, the outer part can be formed partially or completely while engaged with the component. A fugitive spacer can be placed between the outer part and an extension of the component. In various embodiments, the extension can reach into an opening of the outer part and the cap can be coupled with the extension.

Abstract: A turbine blade is provided comprising: a root; an airfoil comprising an external wall extending radially from the root and having a radially outermost portion; and a damping structure. The external wall may comprise first and second side walls joined together to define an inner cavity of the airfoil. The damping structure may be positioned within the airfoil inner cavity and coupled to the airfoil so as to define a tuned mass damper.

Abstract: A rotor blade for a flow machine, in particular a steam turbine, includes an insertion root with a first finger and two second fingers which are arranged on either side of the first finger in axial direction. The first finger and the second fingers have a shoulder in axial direction on axial sides facing one another such that the fingers have a radially outer first portion and a radially inner second portion whose axial extension is shorter than that of the outer, first portion. In relation to a total axial width between axial sides of the two second fingers which face away from one another, the radial height of the first, radially outer portion is in the range of 0.39 to 0.45, particularly 0.40 to 0.44, and the radial height of the second, radially inner portion is between 0.40 and 0.46, particularly between 0.41 and 0.45.

Abstract: A closure bucket for a turbo-machine. In one embodiment, the turbine closure bucket includes a blade section, and a base section positioned adjacent the blade section. The base section of the turbine closure bucket can engage a dovetail slot of a rotor. The base section includes a body having a first end and a second end. The base section also includes an aperture extending through the body of the base section. Additionally, the base section includes an annularly open threaded opening extending along an outer surface of the body. The annularly open threaded opening of the base section is configured to engage a threaded fastener for securing the turbine closure bucket within the dovetail slot of the rotor.

Abstract: Provided is a blade for a rotor of a wind turbine having a substantially horizontal rotor shaft, said rotor comprising a hub, from which the blade extends substantially radially when mounted, said blade having a chord plane extending between a leading edge and a trailing edge of said blade, a root area closest to the hub, an airfoil area furthest away from the hub, a transition area between the root area and the airfoil area, a first airfoil extending substantially along the entire airfoil area, and a second airfoil separately mounted to the blade, said second airfoil arranged at a mutual distance transverse to the chord plane and extending along the root area of the blades.

Abstract: It comprises bushings in at least a first circumferential row in a blade portion and suitable for receiving studs in a hub portion. Bushings comprise an elongated body with lateral faces, lateral faces inclined to each other and major and minor faces into which the lateral faces converge. The connector assembly allows an efficient releasable connection of blade root and hub in a wind turbine rotor.

Abstract: It includes a rotatable hub carrying blades and a device for attaching a portion of the blades to a portion of the hub. The attaching device includes bushings inside of which corresponding studs can be secured. At least some of the bushings are provided with at least one securing end adapted for providing the stud with a degree of rotation relative to the bushing. Bushings may include an inner receiving member for receiving a corresponding end of the stud. The receiving member can be rotated inside the bushing around an axis.

Abstract: An arrangement and a method for mounting articulated turbine buckets in axial entry slots of rotor wheels. A curvature on a vertical plane may be incorporated on an axial male dovetail projection of the bucket root and the associated axial female dovetail slot of the rotor wheel. The curvature facilitates loading of buckets otherwise precluded by interferences, such as interlocking tip shrouds on adjacent buckets. Such loading may be provided by locating the shroud tip shroud in proximity to an adjacent tip shroud and pivoting the root end of the bucket around the location of the tip shroud such that the arc formed by the bucket allows the curvature of the axial male dovetail projection to swing into the axial female dovetail slot of the rotor wheel.

Abstract: Swivel dovetail connections, such as a tangential entry, straight axial entry or curved axial entry dovetails, for connecting a blade and a rotor wheel in a turbomachine are disclosed. A modified shape of dovetail contact surfaces creates a swivel dovetail connection between blades and rotor wheels, and allows limited motion of blades relative to wheels, while still maintaining the structural connection between blades and wheels. The swivel dovetail connection is achieved by providing concave or convex dovetail contact surfaces between a rotor wheel and a blade such that the contact surfaces lie along a common substantially toroidal arc, an axially extending, substantially cylindrical arc, or a substantially frusto-conical arc.

Abstract: Provided is a blade for a rotor of a wind turbine having a substantially horizontal rotor shaft, said rotor comprising a hub, from which the blade extends substantially radially when mounted, said blade having a chord plane extending between a leading edge and a trailing edge of said blade, a root area closest to the hub, an airfoil area furthest away from the hub, a transition area between the root area and the airfoil area, a first airfoil extending substantially along the entire airfoil area, and a second airfoil separately mounted to the blade, said second airfoil arranged at a mutual distance transverse to the chord plane and extending along the root area of the blades.

Abstract: A device for connecting a blade to a rotor shaft of a continuous flow machine, includes a first fork foot which has a quantity of first foot lugs with first bore holes, a second fork foot which has a quantity of second foot lugs with second bore holes, and at least one connection bolt which passes through first and second bore holes to connect the first fork foot to the second fork foot. The device has a first area with a predetermined first diameter difference between a first inner diameter of one of the bore holes and a first outer diameter of the connection bolt, and a second area with a predetermined second diameter difference between a second inner diameter of one of the bore holes and a second outer diameter of the connection bolt, wherein the first diameter difference and the second diameter difference differ from one another.

Abstract: A blade (1) for a rotor of a wind turbine having a substantially horizontal? rotor shaft, said rotor comprising a hub, from which the blade extends substantially radially from said rotor when mounted. The blade (1) has a chord plane (K) extending between the leading edge (5) and the trailing edge (S) of the blade (1). The blade (1) comprises a root area (2) closest to the hub, an airfoil area (4) furthest away from the hub and a transition area (3) between the root area (2) and the airfoil area (4), and comprises a single airfoil along substantially the entire airfoil area (4). The blade (1) comprises at least a first root segment (7) and a second root segment (8) along substantially the entire root area (2), said segments being arranged with a mutual distance, as seen transverse to the chord plane (K). At least one of the root segments (7, 8) has an airfoil profile.

Abstract: A wind turbine blade assembly is provided. The assembly includes at least one wind turbine blade. The blade includes a blade root portion. The assembly also includes at least one blade root hub fitting coupled to the blade root portion. The blade root hub fitting is configured to couple to a rotatable hub.

Abstract: A set of bladed buckets is provided for a turbine wheel having a male dovetail. The turbine wheel includes axial projections projecting outwardly from both sides of the wheel and formed on substantially the entire periphery of the wheel, except for an interruption by a notch formed by removal of portions of the male dovetail at a bucket loading location. A closure group includes a bladed closure bucket and a pair of adjacent bladed buckets, each having a root portion, a platform and an airfoil. The root portions include a pair of radially inwardly extending laterally spaced tangs, and retaining grooves having a non-circular profile. The adjacent bladed buckets are disposed on each side of the bladed closure bucket. A retaining key has a non-circular axial cross section, and is configured to fit into an opening defined by opposing retaining grooves in the bladed closure bucket and bladed buckets.

Abstract: A fully bladed closure design for a turbine wheel with tangential entry. A set of the final three buckets including a bladed closure bucket are disposed about a wheel margin with two buckets adjacent to the bladed closure bucket secured to the wheel margin by the dovetails. The closure bucket is secured to adjacent buckets by a combination of one or more retaining keys and to the margin by one or more retaining pins. The bladed closure bucket and the adjoining faces of the adjacent buckets have flat skirts providing suppport from the retaining keys across the full axial width of the bladed closure bucket and the adjacent buckets.

Abstract: Tangential entry dovetail cantilever load sharing is described herein. In one embodiment, a turbine bucket dovetail is provided that facilitates substantially even distribution of centrifugal loads on a plurality of hooks that define the bucket dovetail.

Abstract: A blower fan includes a housing having a compartment. A stator and an impeller are mounted in the compartment. The housing further includes an air inlet and an air outlet both communicated with the compartment. The impeller has a hub and a plurality of vanes coupled to the hub. Each vane includes an upper edge whose end is an air input portion adjacent to the air inlet of the housing, and an air gap is formed between the upper edge of each vane and a top of the housing, with various widths of the air gap ranging from 0.3 mm to 2.0 mm, while a shortest width of the air gap is formed between the air input portion of the upper edge and the top of the housing for providing reduced turbulence and noises.

Abstract: A closure bucket group for mounting on a dovetail of a turbine wheel. The closure bucket group may include a leading bucket with a leading bucket rear side, a closure bucket with a closure bucket front side and a closure bucket rear side, and a trailing bucket with a trailing bucket front side. The leading bucket rear side and the closure bucket front side define a first enclosed keyway and the closure bucket rear side and the trailing bucket front side define a second enclosed keyway. A number of keys may be positioned within the first enclosed keyway and the second enclosed keyway so as to support the closure bucket.

Abstract: A fully bladed closure design for turbine wheel with tangential entry. A set of the final three buckets including a bladed closure bucket are disposed about a wheel margin with two buckets adjacent to the bladed closure bucket secured to the wheel margin by the dovetails. The closure bucket is secured to adjacent buckets by a combination of one or more retaining keys and to the margin by one or more retaining pins. The bladed closure bucket and the adjoining faces of the adjacent buckets have flat skirts providing suppport from the retaining keys across the full axial width of the bladed closure bucket and the adjacent buckets.

Abstract: A turbine moving blade has a blade portion extending from the basal portion to the tip of the moving blade. The blade root portion is formed at the basal portion of the blade portion and engaged with a corresponding disk groove of a turbine rotor on a one-by-one basis, and the integral cover is formed at the tip of the blade portion integrally with the blade portion. The integral cover includes at least a pair of pressure and suction sloped surfaces inclined relative to the direction of the rotational axis of a turbine so as to restrain the elastic restoring force of the moving blade torsionally deformed at the time of installation of the moving blade by bringing the integral covers of mutually adjacent blades into contact.

Abstract: A fan blade assembly includes a fan blade and a blade iron. The proximal end of the blade iron is configured for securement to a conventional, commercially available fan motor. An openwork defines the perimeter of the fan blade. A decorative cover spans and is secured to the openwork. The distal end of the blade iron includes a fixture for detachably receiving and holding the proximal end of the openwork.

Abstract: Rhombic shrouded tangential entry buckets are circumferentially applied to the rotor wheel rim of a turbine. A fixture is releasably secured to a lug on each bucket and includes a chamfered surface for engaging a complementary surface on the lug. Upon applying a tangential assembly force, the shroud and airfoil of adjacent buckets are pre-twisted in a rotational direction about a generally radial axis enabling dovetail faces to contact one another notwithstanding interference fit shroud contacting surfaces. The removal of the fixture from the lug enables the bias of the airfoil to rotate the shroud in an opposite direction into final assembly with the shroud edges of adjacent buckets in contact with one another and the dovetail faces thereof in contact with one another.

Abstract: A locking arrangement for a row of radial entry blades (62) of a turbo-machine. A closing blade (66) includes a root portion (74) having an axial attachment shape (78) for engagement with an axially oriented slot having an axial attachment shape (76) formed at the entering slot location (34) of the radial entry rotor disk (56). For applications utilizing blades with curved platform faces (112), a preceding blade (108) and a following blade (110) in the row are designed with one curved face for abutting adjacent radial entry blades and one flat face (120) for abutting the flat closing blade faces (116). The closing blade (84) may be designed with a root portion (88) having two legs (90,92) that are urged apart by a key (86) into tight contact with the adjacent blades.

Abstract: The root region of a flowpath through a turbine includes a sealing configuration for minimizing leakage flow and secondary aerodynamic losses. Entrance and exit root radial seals are provided between upstream and downstream nozzles at locations radially inwardly of the root region of the flowpath to minimize radial leakage flow. To minimize intrusion flow into the flowpath from rotor pumping action and consequent aerodynamic losses, an exit flow guide on each bucket turns the exiting radial flow in a predominantly axial direction. Additionally, the upstream bucket root radius and nozzle root radius are faired or tapered to minimize the possibility of a protuberance projecting into the flowpath at steady state operation. An additional entrance root axial fin is provided on the buckets to reduce the flow coefficient and afford further reduction in leakage flow.

Abstract: A turbine wheel including a male dovetail configuration about substantially an entire periphery of the wheel, interrupted by a notch formed by removal of portions of the male dovetail at a bucket loading location on the periphery of the wheel. A closure bucket adapted for loading onto the wheel includes a root portion, a platform and airfoil, the root portion formed with a pair of radially inwardly extending laterally spaced tangs, the tangs each formed with a pair of radially aligned retaining pin holes, the retaining pin holes located radially inwardly of the male dovetail configuration.

Abstract: A turbine wheel including a male dovetail configuration about substantially an entire periphery of the wheel, interrupted by a notch formed by removal of portions of the male dovetail at a bucket loading location on the periphery of the wheel. A closure bucket adapted for loading onto the wheel includes a root portion, a platform and airfoil, the root portion formed with a pair of radially inwardly extending laterally spaced tangs, the tangs each formed with a pair of radially aligned retaining pin holes, the retaining pin holes located radially inwardly of the male dovetail configuration.

Abstract: A dovetail joint between a rotor wheel and a bucket includes a male dovetail component on the rotor wheel and a female dovetail component on the bucket. The male dovetail component has axially projecting hooks with slanted surfaces along generally radially inwardly directed surfaces. The slanted surfaces form included angles with a plane normal to the axis of rotation and bisecting the wheel dovetail which are larger than 90° and remain constant for all of the hooks. Single radius fillets are also provided along the transition surfaces between the slanted crush surfaces and the neck surfaces. The stress concentrations are therefore minimized.

Abstract: A dovetail joint between a rotor wheel and a bucket includes a male dovetail component on the rotor wheel and a female dovetail component on the bucket. The male dovetail component has axially projecting hooks with slanted surfaces along generally radially inwardly directed surfaces. The slanted surfaces form included angles with a plane normal to the axis of rotation and bisecting the wheel dovetail which are larger than 90° and remain constant for all of the hooks. Single radius fillets are also provided along the transition surfaces between the slanted crush surfaces and the neck surfaces. The stress concentrations are therefore minimized.

Abstract: A multiple hook dovetail connection for connecting a rotor wheel and a bucket of a turbine rotor that permits the use of wider vanes at the ends of the buckets without changing the size of the wheel and the other existing components of the turbine. The dovetail connection comprises a male dovetail component and a female dovetail component. The male dovetail component includes first and second hooks. Each of the hooks includes a crush surface, a neck and an angle formed between the crush surface and the neck. These hooks are dimensioned in accordance with at least one of the included tables.

Abstract: A multiple hook dovetail connection for connecting a rotor wheel and a bucket for a turbine rotor that permits the use of wider vanes at the ends of the buckets without changing the size of the wheel and the other existing components of the turbine. The dovetail connection comprises a male dovetail component and a female dovetail component. The male dovetail component includes a plurality of hooks. Each of the hooks includes a crush surface, a neck and an angle formed between the crush surface and the neck. These books are dimensioned in accordance with at least one of the included tables.

Abstract: A turbine closure bucket adapted to complete assembly of a row of tangential entry buckets on a rotor wheel includes an airfoil portion and a mounting portion for mounting the bucket to a turbine wheel. The mounting portion has front and back faces, with weight reduction cavities formed internally in the front and back faces. Externally, the front and back faces of the closure bucket are substantially identical to front and back faces of adjacent buckets in the row.

Abstract: A method has been developed for removing turbine buckets that have become stuck to a turbine rotor wheel. This method includes making two or more first cuts to the base of a female dovetail of the turbine bucket. Two or more second cuts are also made to a lower neck of the female dovetail. The blade of the bucket is broken off at the first cut, which breakage also splits the base of the dovetail into two sections. These sections are pressed down along the second cuts so that they may be removed from the wheel.

Abstract: A fluid flow machine wheel as for an immersion agitator or for a waste water, slurry, sewage or feces pump or for a recirculation pump, comprises a shaft hub having an inner hub portion and an outer hub portion, between which there is disposed a hub damping element comprising an elastic material. Blades project from the outer hub portion. Blade damping elements of elastic material are provided between the outer hub portion and each respective blade. The fluid flow machine wheel may have either only the hub damping element or only the blade damping elements. The damping element or elements at least reduce vibration of or damage to the wheel or its drive motor, transmission, mountings for same and so forth, caused by uncontrolled hydraulic conditions or properties and afflux flows.

Abstract: A dovetail joint between a rotor wheel and a bucket includes a male dovetail component on the rotor wheel and a female dovetail component in the bucket. The male dovetail component has axially projecting hooks with slanted crush surfaces along generally radially inwardly directed surfaces. The slanted surfaces form included angles with neck portions parallel to a plane normal to the axis of rotation which are larger than 90.degree. and decrease in included angle from the radially outermost hooks to the radially innermost hook where the angle is 90.degree.. Compound fillets are also provided along the transition surfaces between the slanted crush surfaces and the neck surfaces. Thus, stress concentrations are minimized.

Abstract: A dovetail assembly for mounting blades with dovetail roots axially into disk dovetail slots around a disk periphery which is subject to a tensile stress field due to centrifugal and thermal growth induced forces generated by the rotor when the rotor is rotating. The dovetail assembly has stress risers each in the form of a transition fillet between a neck or an area of minimum width and a pressure face which is designed to be a contact surface between complementary blade dovetail roots and disk dovetail slots formed between adjacent disk posts. The region around the stress riser has deep compressive residual stresses imparted by laser shock peening and is radially adjacent the stress riser and extends inward from a laser shocked surface of the component along the transition fillet.

Abstract: A turbine engine rotor assembly disk is provided which includes a forward web, an aft web, a plurality of first stub shafts, and a plurality of second stub shafts. The first and second stub shafts have axial ends and web ends. The stub shafts are attached to the respective forward or aft web, at the web end. The first and second stub shafts are equal in number, similarly spaced around the axial centerline, and attached to one another by fasteners.

Abstract: In a steam turbine rotor wheel and bucket dovetail joint construction wherein the wheel dovetail includes a plurality of radially adjacent hooks interconnected by respective necks, each having an upper and lower fillet pair of substantially identical fillet, an improvement wherein each upper fillet has a compound radius.

Abstract: In an axial-flow turbine, at least one of front and rear side contact surfaces of shrouds (3a or 3b) of blades (1a or 1b) with respect to the turbine rotational direction is formed at certain angle with respect to a radial line connecting the rotor center and the contact surface. The shroud (3a) of the blade (1a) of a first kind is formed in a trapezoidal shape converging radially outward in cross section taken in a plane perpendicular to the turbine axial direction, and the shroud (3b) of the blade (1b) of a second kind is formed in an inverted trapezoidal shape converging radially inward in the cross section. Further, half of an angle (2.alpha.) between the front and rear side contact surfaces of the shrouds (3a or 3b) is made smaller than a static frictional angle of the contact surface.

Abstract: A turbine wheel and bucket assembly comprising a wheel having a peripheral rim machined to include a dovetail shape about the circumference of the rim, interrupted only by a bucket installation slot; and a plurality of buckets installed on the wheel, each bucket having a dovetail portion and blade portion, with the dovetail portion machined to include a complimentary dovetail shape enabling each bucket to be slidably received on the wheel dovetail shape; each bucket having an integral cover at a radial tip of the blade portion, each cover having axially extending surfaces on either side of angled contact surfaces adapted to engage mating contact surfaces of adjacent covers such that the buckets are pretwisted in a first direction. The dovetail shape includes a keyway and a complimentary key is provided on the rim of the wheel, the key receivable within the keyway to prevent rotation of the dovetail portion of the bucket relative to the wheel.

Abstract: In a steam turbine rotor wheel and bucket dovetail joint construction wherein the wheel dovetail includes three radially aligned hooks each interconnected by a neck having an upper and lower fillet, an improvement includes redesigned fillet radii which, in a first embodiment, include the upper fillet having a radius greater than the lower fillet radius. In certain embodiments, the upper fillet may have a radius twice that of the lower fillet. In other embodiments, the radii in both the upper and lower fillets have been enlarged.

Abstract: A dovetail joint between a rotor wheel and a bucket includes a male dovetail component on the rotor wheel and a female dovetail component in the bucket, wherein the male dovetail component includes four laterally projecting hooks, each hook from an uppermost hook to a lowermost hook decreasing in radial thickness and increasing in axial length. Each hook has a substantially flat top surface to effectively increase the average thickness, and a neck between the respective hooks having enlarged fillets. The new dovetail joint reduces peak stresses so as to avoid or minimize stress corrosion cracking.

Abstract: A turbomachine rotor includes a disk having a plurality of annular ribs projecting from its periphery to define a plurality of annular grooves, and a plurality of blades, preferably made of composite material, evenly distributed around the periphery of the disk, each blade having a notched root defining heels which fit into the grooves of the disk and which are divided into two groups, one group being offset on the pressure side of the blade and the other group being offset on the suction side so that the heels of the second group align with the heels of the first group of an adjacent blade, the blades being fixed to the disk by pins which extend through the aligned heels of adjacent blades and the ribs of the disk. Each blade is thus secured by two pins, and each pin helps to secure two blades.

Abstract: To attach blades (5) on a rotor wheel for turbines or compressors, the wheel (1) has threads (2) running to the inside in a spiral shape on both sides of the outer edge. The blades (5) have segments on their feet (7) of counter-threads shaped accordingly. The threads are designed to have one turn, and their beginnings are staggered 180.degree. to one another on both sides of the wheel to offset inbalances. The threads on the wheel and on the blade feet there are self-locking and prestressed.

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: The pre-load device for a turbomachine rotor according to the invention has a shank formed of a superplastic material which is axially insertable in a shank bore formed between confronting notches formed on a rotor disk and a blade root portion. In one embodiment, the notches extend generally parallel to the longitudinal axis of rotation of the rotor disk. The shank defines an interior chamber in which is located a low-melting point material. An electrical resistance heating element is located in the low-melting point material and has means to be connected to an electrical source. The device also includes headed portions attached to each end of the shank, each of the headed portions bearing against axially facing surfaces of the rotor disk and the blade root so that, when the head means are attached, relative axial movement between the elements is prevented.