Abstract: A gas turbine rotor blade includes a shroud which is cooled effectively with cooling gas used for cooling the blade profile so that the temperature of the shroud is reduced and the life of the gas turbine rotor blade is extended. A two-step groove is engraved in the shroud along the tip of the blade profile and the upper portion of the two-step groove is plugged. Second cooling holes are bored along the direction of the plane of the shroud so as to be connected to and communicate with the first cooling holes which are bored in the blade profile in a direction along the longitudinal axis of the blade for passing cooling gas through the blade. Consequently, most of the cooling gas, after cooling the blade profile, can be used for cooling the shroud, so that the shroud is cooled effectively and the temperature thereof is prevented from rising. Preventing the temperature from rising can also prevent reduction of the creep resistance of the shroud and prevent the blade root on the shroud from being turned up.

Abstract: The present turbine wheel assembly increases component life and turbine engine longevity. The combination of the strap and the opening combined with the preestablished area of the outer surface of the opening and the preestablished area of the outer circumferential surface of the strap and the friction between the strap and the opening increases the life and longevity of the turbine wheel assembly. Furthermore, the mass "M" or combined mass "CM" of the strap or straps and the centrifugal force assist in controlling vibrations and damping characteristics.

Abstract: A plastic fan includes two injection molded parts, each of which includes its own hub and a set blades extending outwardly from the hub to a band. The two parts are co-operatively sized and shaped to be assembled into a single operable fan having: 1) a hub comprising the hubs of each of the component parts; 2) the blades of the component parts; and 3) a circumferential band comprising the bands of the component parts. The fan blade separation on each of the fan parts is relatively large, permitting separate injection molding of each part. The resulting fan may be designed to have far greater blade number and blade solidity that would be possible for a fan that is injection molded by standard techniques. The fan may be packaged in an airhandler assembly that includes a flexible cylindrical retraining member generally coaxial with, and external to, a rigid cylindrical member, the fan band and the stator assembly, so as to support the stator assembly and to maintain the parts in place.

Abstract: A large air moving fan has a number of hollow airfoil blades extending generally radially from a rotatable hub. The tips of the blades are surrounded by a circumferential shroud leaving a narrow gap between the tips of the blades and the shroud. A fin on the tip of each blade extends substantially perpendicular to the transverse cross section of the blade. The outline of the fin corresponds approximately to the shape the airfoil at the tip of the blade and the fin is curved so as to be substantially parallel to the shroud. It is believed that the fin prevents direct radial flow of a boundary layer of air from the outside surface of the blade into the gap between the tip of the blade and the shroud. This reduces the turbulence adjacent to the tip of the blade since the air traveling radially along the blade does not mix as violently with air passing through the gap from the high pressure side of the fan to the low pressure side of the fan. Noise reduction in the order of 3 db is obtained.

Abstract: A turbine blade is provided with a shroud having at least one cooling air passage extending through it. A plurality of small apertures in the passage direct cooling air as a film across the outer surface of the shroud thereby cooling it. The shroud is therefore thinner and lighter than previous shrouds which are typically provided with a large number of internal cooling air passages.

Abstract: A friction damper (50) provides friction damping for gas turbine engine airfoils to reduce vibrations therein. The friction damper (50) includes a plate (52) underlying radially outer shrouds (30) of two adjacent airfoils (20). Friction generated between an outer surface (53) of the plate (52) and undersides (42) of the adjacent shrouds (30) reduces undesirable vibrations in the airfoils (20).

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: The total number (M) of plural blades of a blade apparatus is selected so as not to be a prime number and not to be a power multiplier of a prime number. Plural blades are divided into at least a first blade group in which one blade group has the blades of a first integer number (N.sub.1) and a second blade group in which one blade group has blades of a second integer number (N.sub.2). Each of the first integer number (N.sub.1) and the second integer number (N.sub.2) have no common divisor except 1. The total number (M) of plural blades is the product of the first integer number (N.sub.1) and the second integer number (N.sub.2). The blades of the first integer number (N.sub.1) blade group are connected by a first stage connecting member and the blades of the second integer number (N.sub.2) blade group are connected by a second stage connecting member.

Abstract: A gas turbine blade having a shroud extending outwardly from the tip of the airfoil portion of the blade. The shroud is cooled by cooling air passages formed within it. A radial cooling air supply hole directs cooling air directly from the blade root through the airfoil and to the shroud. A plurality of cooling air passages extend from the supply hole and are disposed adjacent bearing surfaces along which the shroud contacts the shroud of an adjacent blade. One of these cooling air holes is formed in the portion of the shroud that projects from the convex surface of the airfoil and another one of the cooling air holes is formed in the portion of the shroud that projects from the concave surface of the airfoil. The cooling air holes extend to the edge of the shroud and discharge the cooling through an opening in the edge.

Abstract: A compressor or fan blade (112) for a gas turbine engine includes a suction surface midspan shroud (122) which is cambered so that the shroud trailing edge (132) is substantially aligned with the direction of the air flow in the vicinity of the shroud trailing edge (132). The cambered portion originates at the chordwise location where a shock wave (60) attached to the leading edge of the neighboring blade crosses the shroud (136). The cambered portion gradually transitions to an uncambered profile at a circumferential location intermediate the suction surface (110) of the blade (112) and the pressure surface shroud of the neighboring blade.

Abstract: A cooled turbine blade is described that has shroud band segment in which three cooling air branch ducts extend essentially perpendicularly to the longitudinal axis of the blade as well as in the circumferential direction of the blade reinforcing band. Cooling air bores branch off the cooling air branch ducts and lead out on the surface of the shroud band segment and form film cooling holes there. A first branch duct is supplied with cooling air by a blade cooling duct which is situated in the leading area, while a second branch duct is connected with another blade cooling duct 13 and the third branch duct is connected with the second branch duct 14.

Abstract: A next-to-the-last stage steam turbine bucket has a profile according to the table set forth in the specification. The buckets also include continuous couplings at the bucket mid-point including nubs on each bucket projecting from opposite sides thereof in generally circumferentially extending directions. A sleeve is disposed between each pair of adjacent buckets and has open opposite ends for receiving the nubs of the adjacent buckets. The cross-sections of the nubs and open ends of the sleeve are generally complementary and non-circular to prevent sleeve rotation during turbine operation. The buckets have a continuous cover including cover elements having tenons projecting from opposite sides for reception in corresponding openings in the tips of adjacent buckets.

Abstract: A propeller having a central hub portion with multiple blades affixed to the hub portion and spaced around the circumference of the hub to extend outwardly therefrom is provided. An annular ring or shroud joins the tips of the blades, a portion of each blade tip being free of the annular ring on the trailing side of the blade to define a region permitting outward flow of liquid along the blades. By this construction, energy is directed rearwardly from the propeller and the loss of energy due to centrifugal action is reduced.

Abstract: A last-stage steam turbine bucket having a profile according to the charts set forth in the specification.

Abstract: Ship's propeller having a propeller blade having a leading edge and a trailing edge and a free end, and end plates at the free end extending transversely of the blade on both sides of the blade. The line of attachment to the blade of each of the end plates has a chord length less than the chord length of the blade end and the lines of attachment of the end plates overlap each other partly, one end plate extending to the blade leading edge and the other end plate extending to the blade trailing edge. The end plates have airfoil configuration and have leading edges that extend outwardly and rearwardly of the blade with respect to the direction of movement of the blade.

Abstract: A last-stage steam turbine bucket having a profile according to Charts I-XXXXI of Table I.The bucket is divided into a number of profile sections each of which is a predetermined radial distance from the root section. Each point on a profile section at the predetermined radial distance from the root is defined by an X-Y coordinate and a radius R along the arc of a circle connecting adjacent points.

Abstract: A limp propeller for underwater use with a high mechanical damping ability o absorb so-called broadband vibration noise is comprised of a fabric-like material, preferably made of braided high tensile strength material such as fiberglass or graphite fibers. The fabric is devoid of any stiffening plastic or epoxy matrix material. Rather a flexible matrix material having relatively large hysteretic losses when deformed o cyclically in place of the stiffening plastic or epoxy matrix, or no matrix material at all is used in the present invention. The flexible matrix material or the complete absence of any matrix material renders the propeller blade relatively limp to flexure, thereby reducing its acoustic radiation damping or radiation efficiency.

Abstract: A last-stage steam turbine bucket having a profile according to Charts II-XIII, XV-XXVII and XXIX of Table I.

Abstract: In a steam turbine cover (18) for an axial flow steam turbine including a rotor (14), an annular row of radially extending blades (12) carried by the rotor, each blade having a leading edge (150 or 250), a trailing edge and a radial tip, at least one moisture removal groove (146 or 246) extending radially along the blade adjacent the leading edge (150 or 250), and an annular cover assembly coupling the radial tips of the annular row of blades, there is provided a plurality of circumferentially spaced, axially extending notches (158, 160 or 260) formed in the annular entrance edge (134 or 234) of the cover assembly, one notch for each blade, the notch radially exposing the leading edge and moisture removal groove of each such blade.

Abstract: Turbine blades are held in groups formed by a series of spaced lugs constituting a lashing structure. Selected lugs have gaps which are "Z"-shaped, the gaps tending to close during untwisting of the blades when the blades are subjected to high centrifugal forces.

Abstract: An integral covered blading for a turbine is achieved by cutting a short arc cover spanning tips of multiple adjacent blades. Adjacent cover portions are formed for adjacent blades, each portion having facing sides. A material buildup between the facing sides of cover portions is effected and selective machining of the material buildup develops an interface between adjacent cover portions of adjacent blades. Short group blading is thereby converted to equivalent integral covered blading.

Abstract: A shrouded aerofoil assembly such as a turbine rotor for a gas turbine engine has a multiplicity of blades with tip shrouds circumferentially distributed around a rotor disk. Inevitably, in use, the assembly vibrates and must be designed so the potentially most dangerous vibratory modes occur outside the engine speed range. The proposed arrangement has a number of neighbouring blades sharing a common shroud segment. Adjacent shroud segments are interlocked by Z-notch abutments. Blade assemblies have sufficient pre-twist load to maintain frictional contact in the interlocks over the speed range to maintain damping constraints.

Abstract: A tapered twisted rotating blade for the fourth rotating blade row of a BB71 and BB471 turbine has a shroud segment integrally formed on the tip of the airfoil portion such that the shroud is dimensionalized according to materials used so that the tuned frequencies remain the same regardless of materials used, based on changes in Young's modulus due to use of different materials. The blade also has a pitch to chord ratio that increases linearly with length of the blade.

Abstract: A rotor includes a disc having a plurality of blades extending therefrom. The blades include tip shrouds, each having first and second axial ends, and first and second circumferential faces. The first and second faces of adjacent tip shrouds are spaced from each other to define gaps therebetween. The first and second ends each include U-shaped slots, each having an arcuate damper wire disposed therein. The slots are aligned generally parallel to an axial centerline axis of the rotor for allowing ease of manufacture and assembly while providing effective frictional damping by the damper wires urged by centrifugal force against the slots.

Abstract: An integral shroud blade comprising a root portion for mounting the blade in a row on a turbine rotor; a platform portion; an airfoil portion extending upwardly from the platform portion and having a leading edge, a trailing edge, and a tip; a shroud formed on the tip of the airfoil portion and having two opposite tangential side surfaces and a top surface; and at least one pair of holes extending into the shroud, each of the two tangential sides having one hole of each pair being formed therein.

Abstract: A shroud band for a rotor wheel having integral rotor blades wherein the shroud band has at least one Z-shaped separation gap at the band periphery, the Z-shaped gap having two parallel damping gaps which are axially spaced apart and which are inclined at an angle of from 70.degree. to 90.degree. relative to the axial direction. The damping gaps are narrow and are joined by an inclined wider free gap portion. During rotation, the damping gaps close up and the adjoining surfaces of the band come into frictional engagement whereas the free gap remains open.

Abstract: A bladed rotor having blades with blade shrouds includes a deformable protective coating applied to the blades to increase the damage tolerance of the blades during foreign object ingestion. The protective coating deforms upon impact between the shroud and airfoil of adjacent blades. The deformation absorbs impact energy and improves distribution of the impact load transferred between the blades.

Abstract: Taught is an improved tip-shrouded blade and a method of manufacturing the same. In accordance with the present invention, the inventive blade comprises a blade including an airfoil having a residual compressive stress in areas thereof subject to high local stress.

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: A compressor impeller has a ring-shaped shroud band which is mounted at blade tips, each blade tip being enclosed in an identical radially slidable manner by a guide block, and the guide blocks being fastened to the shroud band. As a result, a narrow sealing gap and thus lower aerodynamic losses can be implemented than in conventional compressors, and the different centrifugally and thermally induced expansions of the blade and of the shroud band can be compensated.

Abstract: The rotor of a turbomachine has a rotor blade stage formed by sectors which are each secured to a rotor drum by radially inwardly directed, axially spaced flanges on the blade platform of the sector cooperating with radially outwardly directed, axially spaced flanges on the drum. The cooperating downstream flanges of the drum and the blade platform have at least one pair of registering holes through which a cylindrical pin extends, the pin having a radial collar interposed between the two flanges and an annular groove positioned downstream from the collar. The assembly is held in position by scalloped segments which are inserted into an annular groove in the drum on the downstream side of the downstream flange, and which are shifted circumferentially to engage edges thereof in the grooves of the pins before being locked by tongues at opposite ends of the segments.

Abstract: In order to clamp blades (1, 2, n) of turbomachines to influence the blade vibration occuring in such machines, the shroud plates (1a, 2a, na) are dimensioned in such a way that they are in contact with one another in the installed condition without clearance and without contact force or else they are dimensioned so that they exhibit a gap (3) relative to each other. A prestressed or pretorsioned, clearance-free connection occures between the shroud plates (1a, 2a, na) due to plastic deformation of the shroud plates (1a, 2a, na) in the region of their boundries or of the gap (3).

Abstract: Moving blading for a steam turbine, the blading comprising blades (1) having respective bodies (3) provided with caps or fins (4), said caps or fins (4) on adjacent blades coming into contact at least during rotation of the blading over a plane surface which is substantially parallel to the radial axis (Z'Z) of the blade and giving rise to blade body twisting by virtue of said contacts (7, 8), the blading being characterized in that, in addition to the contacts (7 and 8) between adjacent caps or fins (4), it includes a link which is provided by means of additional contacts (A, A') free to slide rectilinearly in a plane corresponding to the plane of each cap or fin (4) along an axis which is substantially perpendicular to the axis of rotation OO' of the blading, said additional contacts (A, A') being situated at a relatively large distance from said contacts (7, 8) which give rise to twisting. The invention improves the vibration properties of the blades.

Abstract: A propeller enclosed in an open tube and attached to the tube, with the tube being driven by an engine through a ring gear rack on the outside of the tube, a stationary housing concentrically outside the tube and attached to the boat hull, bearings and seals between the housing and the tube to permit the space between the housing and tube to be filled with lubricating oil, and a pivotable rudder located partially inside and partially outisde the aft end of the tube.

Abstract: Blading for a rotating thermal machine consists of an airfoil (1), a root (4) and a shroud plate (5) or a shroud, the tip (2) of the airfoil (1) having a spigot-type step (11) with a semi-circular groove (12) extending around the whole periphery of its generated surface. The shroud plate (5) or the shroud has a recess corresponding to the step (11) with a semi-circular groove (8) extending around the complete periphery. At least one piece of a firmly seated heat-resisting wire (10) is located in the circular duct formed by the grooves (8, 12) as the fastening element between the components (1, 5). The blading is manufactured by pushing and/or pulling the wire (10) sideways into the duct formed by the grooves (8, 12).

Abstract: In turbines, gaps arising between adjacent shrouds of integrally shrouded blades at high temperature are controlled or eliminated using pins inserted into opposing faces of shroud portions. These pins have a coefficient of thermal expansion greater than the integrally shrouded blade material and at least equal to that of the rotor material and, thus, protrude outwardly at operating temperatures. These protruding pins act to close the gap between shroud portions, thereby reducing vibration.

Abstract: A control wheel intended for welding onto the high-pressure rotor of a steam turbine is manufactured from a ring of individual blades welded together. For this purpose, all of the individual blades are provided with shrouds and root platforms having welding grooves formed therein. After being welded together into a ring, closed on all sides, the control wheel is annealed, machined and finally heat-treated.

Abstract: A compressor blade assembly for a compressor operating at transonic or supersonic blade speeds has a part span shroud. The shroud is twisted having a first angle in the direction of airflow on one side of the shock wave and a second angle in the direction of airflow on the other side of the shock wave.

Abstract: A steam turbine of the type employing a plurality of axial entry, integral shroud blades comprises spring means resident in a slot machined in at least one face of each shroud. The spring means urge against the adjacent shroud and reduce relative motion between adjacent blades.

Abstract: A steam turbine of the type employing axial entry, integral shroud blades has a pin disposed between adjacent shrouds that extends into tangentially oriented holes in the opposing faces of adjacent shrouds. The pins reduce blade flop during turning gear operation and reduce blade vibration during operation under load.

Abstract: In order to damp blade vibrations, the shroud plates of the blades are equipped with magnet inserts.

Abstract: Turbine blades are held in long arc groups by a shroud structure, with gaps between segments of the shroud structure. These gaps are Z-shaped, the gaps tending to close due to untwisting of the blades when the blades are subjected to high centrifugal forces.

Abstract: In the rotor blade ring of an axial flow turbomachine, the rotor blades are each provided at their radially outer ends with a shroud plate and are fastened at their radially inner ends, by means of a root, in a corresponding groove of the machine rotor. The shroud plates are connected together in the peripheral direction by means of wires rolled into turned recesses. Grooves (10), with a clear width (w.sub.1) which is dimensioned larger than the width (w.sub.2) of the shroud plate turned recess (8) provided for the wire (7) to be rolled in, are machined in the end surface (6) of the shroud plate (2). A spacer means (11), surrounding the wire at least in the region of the rolling positions and removable after rolling, is laid in the grooves during the rolling procedure. This material is preferably a hard paper which is burnt to ashes during machine operation.

Abstract: The present invention discloses a turbomachinery blading configuration. The configuration includes a circumferential recess in a blade support structure and a plurality of blades. Each blade has a platform for mounting the blade within the recess. Each platform includes oppositely directed, generally circumferentially facing edges, each edge having a first and second axial surfaces separated by a recess. The surfaces contact matching surfaces on adjacent blades thereby determining predictable load paths for tangential and twisting moment reaction forces acting on the blades.

Abstract: The invention relates to a high peripheral speed centrifugal compressor of the kind comprising curved hollow sector shaped scoops juxtaposed circumferentially about an axis to form a disc, and a drive shaft for rotating said disc about said axis.According to the invention, the scoops are made from material loaded with high mechanical strength fibers and are connected together circumferentially and radially by filaments wound and stretched in radial clearances between the scoops, the filaments being of material generally similar to the fibers of the scoops and being coated with a bonding agent compatible with the material of the scoops and the filaments, the bonding agent being cured so as to bond the scoops and filaments solidly together in the form of a stable unitary member.The resulting wheel has light weight and high mechanical breakage strength, enabling high peripheral speed.

Abstract: An air conveying device is provided on a radiator for water cooled internal combustion engines. The device comprises a fan rotor supported on the internal combustion engine by means of a fan rotor shaft on which is located a belt pulley for a driving belt. A fan shroud surrounds the outer ends of the fan blades and is fastened to the blade tips. So that even belts with a relatively short belt length can be installed from the fan rotor direction, the fan shroud has at least one slot extending in the axial direction for inserting the belt and for slipping the length of belt which is positioned at the shaft-free end of the fan rotor over the fan shroud.

Abstract: A stage of an axial flow turbine includes a plurality of spaced apart buckets and a plurality of spaced apart nozzle partitions, each plurality respectively circumferentially aligned about and axially spaced from each other along a rotor of the turbine. The nozzle partitions are circumferentially spaced such that a minimum throat extends a predetermined radial distance from the root, thereby forming a converging-diverging flow passageway between nozzle partitions. The trailing edge of the nozzle partitions are disposed to include axial and tangential lean with respect to the rotor. Buckets include a plurality of covers respectively connecting the tips and having a single outward radially extending sealing rib on the radially outer surface of each cover, wherein each rib is tangentially aligned with respective adjacent ribs. Buckets are overtwisted to compensate for untwist at operational speed to achieve optimum efficiency.

Abstract: A fixture 34 for positioning a shroud 22 of a worn rotor blade 14 with respect to an apparatus for removing material is disclosed. The fixture is formed of a base 42, an axial locator 44 which is adapted to engage the root 18 of the rotor blade, and a tangential locator 46 which engages the root of the rotor blade at a hinge joint 58 and which engages the airfoil 20 of the rotor blade. A method of restoring a shroud of the rotor blade axially with respect to the root and tangentially with respect to the airfoil is also disclosed. In an alternate embodiment, a second locator 160 for indexing the locator from an airfoil edge is included.

Abstract: An improved blade rotor structure for an axial flow turbine substantially reduces vibratory stress at resonant frequencies by rigidly connecting the blades to each other in groups equal in number to .[.an integer multiple of.]. the resonant frequency of the blades (i.e. a harmonic frequency) divided by .Iadd.an integer multiple of .Iaddend.the rotor running speed. Flexible tie means are used for connecting adjacent groups of blades together for substantially reducing axial-torsional vibration of the blades.