US2501038A - Mounting for hollow turbine blades - Google Patents

Mounting for hollow turbine blades Download PDF

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Publication number
US2501038A
US2501038A US738023A US73802347A US2501038A US 2501038 A US2501038 A US 2501038A US 738023 A US738023 A US 738023A US 73802347 A US73802347 A US 73802347A US 2501038 A US2501038 A US 2501038A
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United States
Prior art keywords
blade
post
mounting
hollow
radial
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Expired - Lifetime
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US738023A
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Karl E Fransson
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Raytheon Technologies Corp
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United Aircraft Corp
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01DNON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
    • F01D5/00Blades; Blade-carrying members; Heating, heat-insulating, cooling or antivibration means on the blades or the members
    • F01D5/30Fixing blades to rotors; Blade roots ; Blade spacers
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01DNON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
    • F01D5/00Blades; Blade-carrying members; Heating, heat-insulating, cooling or antivibration means on the blades or the members
    • F01D5/12Blades
    • F01D5/14Form or construction
    • F01D5/18Hollow blades, i.e. blades with cooling or heating channels or cavities; Heating, heat-insulating or cooling means on blades
    • F01D5/181Blades having a closed internal cavity containing a cooling medium, e.g. sodium
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01DNON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
    • F01D5/00Blades; Blade-carrying members; Heating, heat-insulating, cooling or antivibration means on the blades or the members
    • F01D5/30Fixing blades to rotors; Blade roots ; Blade spacers
    • F01D5/3069Fixing blades to rotors; Blade roots ; Blade spacers between two discs or rings
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01DNON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
    • F01D5/00Blades; Blade-carrying members; Heating, heat-insulating, cooling or antivibration means on the blades or the members
    • F01D5/30Fixing blades to rotors; Blade roots ; Blade spacers
    • F01D5/3084Fixing blades to rotors; Blade roots ; Blade spacers the blades being made of ceramics
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02TCLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T50/00Aeronautics or air transport
    • Y02T50/60Efficient propulsion technologies, e.g. for aircraft

Definitions

  • This invention relates to an arrangement for mounting a hollow turbine blade on a turbine rotor.
  • the turbine blade is positioned over a supporting post and is welded to the post at a point between its ends with the blade otherwise free from connection to the post.
  • a feature of this application is an arrangement for mounting the hollow blade over a supporting post so that it will be free to expand radially with respect to the post but is supported against axial movement at spaced points.
  • Another feature is an arrangement for positioning the turbine blade on the supporting post in such a manner that the loads on the blade, when the turbine is operating, will be compressive loads rather than tensile loads.
  • a feature of the invention is an arrangement of the rotor such that the blade-supporting post with the blade mounted thereon may be attached to the rotor without the necessity for mounting the blades on the posts while the latter are on the remainder of the rotor.
  • Another feature is an arrangement for coolingthe posts to retain the necessary strength on the post in spite of the high temperature of the gas flowing over the blade.
  • Fig. l is a sectional view through a turbine rotor showing the blade mounting.
  • Fig. 2 is a sectional view along the line 2-2 of Fig. 1.
  • Fig. 3 is a fragmentary sectional view similar to Fig. 1, showing a modification.
  • the turbine rotor which may be a single or multistage axial flow turbine rotor, may be so constructed that each stage consists of a pair of discs 6 having lateral grooves 8 therein facing each other and in a position to engage with the root ID of the post I! which supports the hollow blade [4.
  • the blade H which may be substantially airfoil shape in cross-section, as shown in Fig. 2, has a substantially uniform wall thickness to assure uniform heating and cooling of the blade.
  • the blade is fastened, as by a weld IE, to the outer end of the post I2 so that during rotation of the turbine rotor, the blade will be loaded substantially in compression as a result of the centrifugal forces acting on the blade.
  • the post l2 AdJacent the inner end of the blade, the post l2 carries a laterally projecting flange I8 2 which pilots the blade, holding it in predetermined relation to the post without interfering with free radial movement of the blade to accommodate thermal expansion.
  • the blade Il may have a projecting rib l9 adjacent the flange I8, the elements of the inner surface of which are radial for engagement with the periphery of the flange regardless of relative thermal expansions.
  • the blade Since the blade is loaded in compression, it will be apparent that it can withstand extremely high temperatures before failure; and since it is arranged so that it is out of contact with the post except at the weld l6, thereby providing an air space 20 surrounding the post, the latter is kept at a much cooler temperature than the blade itself.
  • the blade may be cooled by providing a central passage 22 within the post which may be filled with sodium 23 or other material of high conductivity which preferably will be a liquid at the normal operating temperatures of the turbine.
  • the space between the discs 6 may be supplied with a blast of cooling air which will engage the inner surfaces of the roots of the posts.
  • the post 26, comparable to the post l2 has in this arrangement a flange 28 adjacent its inner end which engages with a cooperating inwardly extending flange 30 on the blade 32 to support the blade against radial outward movement and thereby maintain the blade in predetermined relation to the post.
  • the blade 32 is supported by a ring 34 integral with the post which guides the blade in such a manner as to maintain its predetermined relation to the axis of the post but to permit radial movement of the outer end of the blade.
  • the outer end of the blade may have an inwardly projecting rib 38 with the elements of its inner surface radial to assure contact between the ring 34 and the blade regardless of relative thermal expansions. In this arrangement the blade is spaced from the post except at its points of attachment to form an insulating air space 36.
  • a turbine rotor having a number of radiallyextending blade-supporting posts and a hollow blade positioned o er each post, each blade havin: means for attaching it directly to the post at only one radial point, and means for piloting the blade on said post at another radial point spaced from the point of attachment, said blade being otherwise spaced from said post by an airchamber completely surrounding said post.
  • a turbine rotor having a number 01 radiallyextending blade-supporting posts and a hollow blade positioned over each post, each blade having means for attaching it directly to the post at only one radial point, and means for piloting the blade on said post adjacent its inner end, said blade being otherwise spaced from said post by an airchamber completely surrounding said post.
  • a turbine rotor having a number of radiallyextending blade-supporting posts and a hollow blade positioned over each post, each blade having means for attaching it directly to the post at only one radial point, and means for piloting the blade on said post adjacent the outer end thereby providing for free radial expansion of the blade with regard to the post, said blade being otherwise spaced from airchamber completely surrounding said post.
  • a turbine rotor having a number of radiallyextending blade-supporting posts all in substantially the same plane, and a hollow blade positioned over each post, said blade having walls of substantially uniform thickness throughout and being substantially airfoil shape in cross-section, each blade having means for attaching it disaid post by an rectly to the post at only one radial point, and
  • a disk having pieces positioned and held by said disk, and hollow blade elements mounted over each post, each of said blade elements having a relatively thin wall of substantially uniform thickness, each of said blade elements being directly attached to a post adjacent one end, and means on the post adjacent the other end of the blade element for guiding the blade element on the post without restricting radial movement of the blade relative to the post, said blade being otherwise spaced from said post by an airchamber completely surrounding said post.

Description

March 21, 1950 K. E. FRANSSON MOUNTING FOR HOLLOW TURBINE BLADES Filed March 29, 1947 m ay/Z INVENTOR la 1/ 4" It. I vzzz s14 41 ad I ATTORNEY Patented Mar. 21, 1950 UNITED STATES PATENT OFFICE MOUNTING FOR HOLLOW TURBINE BLADES Application March 29, 1941, Serial No. 738,023
Claims. (Cl. 253-77) This invention relates to an arrangement for mounting a hollow turbine blade on a turbine rotor. In the co-pending application of Buck, Serial No. 738,062, filed March 29, 1947, the turbine blade is positioned over a supporting post and is welded to the post at a point between its ends with the blade otherwise free from connection to the post. A feature of this application is an arrangement for mounting the hollow blade over a supporting post so that it will be free to expand radially with respect to the post but is supported against axial movement at spaced points. Another feature is an arrangement for positioning the turbine blade on the supporting post in such a manner that the loads on the blade, when the turbine is operating, will be compressive loads rather than tensile loads.
A feature of the invention is an arrangement of the rotor such that the blade-supporting post with the blade mounted thereon may be attached to the rotor without the necessity for mounting the blades on the posts while the latter are on the remainder of the rotor. Another feature is an arrangement for coolingthe posts to retain the necessary strength on the post in spite of the high temperature of the gas flowing over the blade.
Other objects and advantages will be apparent from the specification and claims and from the accompanying drawings which illustrate an embodiment of the invention.
Fig. l is a sectional view through a turbine rotor showing the blade mounting.
Fig. 2 is a sectional view along the line 2-2 of Fig. 1.
Fig. 3 is a fragmentary sectional view similar to Fig. 1, showing a modification.
As shown in Figs. 1 and 2, the turbine rotor which may be a single or multistage axial flow turbine rotor, may be so constructed that each stage consists of a pair of discs 6 having lateral grooves 8 therein facing each other and in a position to engage with the root ID of the post I! which supports the hollow blade [4. The blade H which may be substantially airfoil shape in cross-section, as shown in Fig. 2, has a substantially uniform wall thickness to assure uniform heating and cooling of the blade. In the arrangement shown, the blade is fastened, as by a weld IE, to the outer end of the post I2 so that during rotation of the turbine rotor, the blade will be loaded substantially in compression as a result of the centrifugal forces acting on the blade. AdJacent the inner end of the blade, the post l2 carries a laterally projecting flange I8 2 which pilots the blade, holding it in predetermined relation to the post without interfering with free radial movement of the blade to accommodate thermal expansion. The blade Il may have a projecting rib l9 adjacent the flange I8, the elements of the inner surface of which are radial for engagement with the periphery of the flange regardless of relative thermal expansions.
Since the blade is loaded in compression, it will be apparent that it can withstand extremely high temperatures before failure; and since it is arranged so that it is out of contact with the post except at the weld l6, thereby providing an air space 20 surrounding the post, the latter is kept at a much cooler temperature than the blade itself. In addition, the blade may be cooled by providing a central passage 22 within the post which may be filled with sodium 23 or other material of high conductivity which preferably will be a liquid at the normal operating temperatures of the turbine. To increase the rate of heat transfer from the post l2 which carries the load of the blade, the space between the discs 6 may be supplied with a blast of cooling air which will engage the inner surfaces of the roots of the posts.
With reference to Fig. 3, the post 26, comparable to the post l2, has in this arrangement a flange 28 adjacent its inner end which engages with a cooperating inwardly extending flange 30 on the blade 32 to support the blade against radial outward movement and thereby maintain the blade in predetermined relation to the post. At the outer end of the post, the blade 32 is supported by a ring 34 integral with the post which guides the blade in such a manner as to maintain its predetermined relation to the axis of the post but to permit radial movement of the outer end of the blade. The outer end of the blade may have an inwardly projecting rib 38 with the elements of its inner surface radial to assure contact between the ring 34 and the blade regardless of relative thermal expansions. In this arrangement the blade is spaced from the post except at its points of attachment to form an insulating air space 36.
It is to be understood that. the invention is not limited to the specific embodiment herein illustrated and described, but may be used in other ways without departure from its spirit as defined by the following claims.
I claim:
1. A turbine rotor having a number of radiallyextending blade-supporting posts and a hollow blade positioned o er each post, each blade havin: means for attaching it directly to the post at only one radial point, and means for piloting the blade on said post at another radial point spaced from the point of attachment, said blade being otherwise spaced from said post by an airchamber completely surrounding said post.
2. A turbine rotor having a number 01 radiallyextending blade-supporting posts and a hollow blade positioned over each post, each blade having means for attaching it directly to the post at only one radial point, and means for piloting the blade on said post adjacent its inner end, said blade being otherwise spaced from said post by an airchamber completely surrounding said post.
3. A turbine rotor having a number of radiallyextending blade-supporting posts and a hollow blade positioned over each post, each blade having means for attaching it directly to the post at only one radial point, and means for piloting the blade on said post adjacent the outer end thereby providing for free radial expansion of the blade with regard to the post, said blade being otherwise spaced from airchamber completely surrounding said post.
4. A turbine rotor having a number of radiallyextending blade-supporting posts all in substantially the same plane, and a hollow blade positioned over each post, said blade having walls of substantially uniform thickness throughout and being substantially airfoil shape in cross-section, each blade having means for attaching it disaid post by an rectly to the post at only one radial point, and
means for piloting the blade for radial movement on said post at another radial point spaced from the point of attachment, said blade being otherwise spaced from said post by an airchamber completely surrounding said post.
5. In a turbine rotor, a disk, a number 01 radially-extending blade-supporting posts having pieces positioned and held by said disk, and hollow blade elements mounted over each post, each of said blade elements having a relatively thin wall of substantially uniform thickness, each of said blade elements being directly attached to a post adjacent one end, and means on the post adjacent the other end of the blade element for guiding the blade element on the post without restricting radial movement of the blade relative to the post, said blade being otherwise spaced from said post by an airchamber completely surrounding said post.
KARL E. FRANSSON.
REFERENCES CITED The following references are of record in the file of this patent:
UNITED STATES PATENTS Number Name Date 1,362,853 Darling Dec. 21, 1920 1,657,192 Belluzzo Jan. 24, 1928 1,966,104 Noack July 10, 1934 2,256,479 Holzwarth Sept. 23, 1941
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Cited By (23)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2696364A (en) * 1948-07-08 1954-12-07 Thompson Prod Inc Turbine bucket
US2708564A (en) * 1952-02-29 1955-05-17 Westinghouse Electric Corp Turbine apparatus
US2744723A (en) * 1949-12-06 1956-05-08 Thompson Prod Inc Controlled temperature fluid flow directing member
US2772852A (en) * 1950-08-03 1956-12-04 Stalker Dev Company Rotor construction for fluid machines
US2772851A (en) * 1950-06-14 1956-12-04 Stalker Dev Company Rotor construction
US2774566A (en) * 1947-12-12 1956-12-18 Richardson Edward Adams Fluid cooled permeable turbine blade
US2786646A (en) * 1949-08-10 1957-03-26 Power Jets Res & Dev Ltd Bladed rotors for axial flow turbines and similarly bladed fluid flow machines
US2802619A (en) * 1950-09-16 1957-08-13 Stalker Dev Company Axial flow rotors for fluid machines
US2839268A (en) * 1950-01-18 1958-06-17 Allis Chalmers Mfg Co Gas turbine
US2858102A (en) * 1954-09-03 1958-10-28 Gen Electric Turbomachine wheels and methods of making the same
US2866616A (en) * 1951-03-02 1958-12-30 Stalker Dev Company Fabricated bladed structures for axial flow machines
US2891719A (en) * 1951-03-02 1959-06-23 Stalker Corp Fabricated axial flow bladed structures
US3055633A (en) * 1957-04-19 1962-09-25 Pouit Robert Hot gas turbines
US3059901A (en) * 1958-04-01 1962-10-23 Carrier Corp Rotor construction
US3314649A (en) * 1963-04-15 1967-04-18 Gen Electric Turbomachine cooling system
US3314650A (en) * 1965-07-20 1967-04-18 Gen Motors Corp Cooled blade
US3330474A (en) * 1965-12-08 1967-07-11 Lister & Co Ltd R A Axial-flow blowers
US4473336A (en) * 1981-09-26 1984-09-25 Rolls-Royce Limited Turbine blades
US4854374A (en) * 1988-02-02 1989-08-08 Frank Harrison Temperature controlling apparatus
US4879880A (en) * 1989-01-17 1989-11-14 Frank Harrison Air temperature regulator
US20150093249A1 (en) * 2013-09-30 2015-04-02 MTU Aero Engines AG Blade for a gas turbine
EP3023191A1 (en) * 2014-11-20 2016-05-25 Siemens Aktiengesellschaft Turbine blade made of two parts
EP3851640A3 (en) * 2020-01-17 2021-07-28 Raytheon Technologies Corporation Rotor assemblies for a gas turbine engine

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1362853A (en) * 1919-03-04 1920-12-21 Electric Service Supplies Co Turbine-wheel and bucket-mounting
US1657192A (en) * 1923-03-22 1928-01-24 Belluzzo Giuseppe Wheel for internal-combustion turbines
US1966104A (en) * 1931-01-19 1934-07-10 Bbc Brown Boveri & Cie Turbine rotor construction
US2256479A (en) * 1938-03-21 1941-09-23 Holzwarth Gas Turbine Co Blade for rotary machines operated by high temperature media

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1362853A (en) * 1919-03-04 1920-12-21 Electric Service Supplies Co Turbine-wheel and bucket-mounting
US1657192A (en) * 1923-03-22 1928-01-24 Belluzzo Giuseppe Wheel for internal-combustion turbines
US1966104A (en) * 1931-01-19 1934-07-10 Bbc Brown Boveri & Cie Turbine rotor construction
US2256479A (en) * 1938-03-21 1941-09-23 Holzwarth Gas Turbine Co Blade for rotary machines operated by high temperature media

Cited By (24)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2774566A (en) * 1947-12-12 1956-12-18 Richardson Edward Adams Fluid cooled permeable turbine blade
US2696364A (en) * 1948-07-08 1954-12-07 Thompson Prod Inc Turbine bucket
US2786646A (en) * 1949-08-10 1957-03-26 Power Jets Res & Dev Ltd Bladed rotors for axial flow turbines and similarly bladed fluid flow machines
US2744723A (en) * 1949-12-06 1956-05-08 Thompson Prod Inc Controlled temperature fluid flow directing member
US2839268A (en) * 1950-01-18 1958-06-17 Allis Chalmers Mfg Co Gas turbine
US2772851A (en) * 1950-06-14 1956-12-04 Stalker Dev Company Rotor construction
US2772852A (en) * 1950-08-03 1956-12-04 Stalker Dev Company Rotor construction for fluid machines
US2802619A (en) * 1950-09-16 1957-08-13 Stalker Dev Company Axial flow rotors for fluid machines
US2866616A (en) * 1951-03-02 1958-12-30 Stalker Dev Company Fabricated bladed structures for axial flow machines
US2891719A (en) * 1951-03-02 1959-06-23 Stalker Corp Fabricated axial flow bladed structures
US2708564A (en) * 1952-02-29 1955-05-17 Westinghouse Electric Corp Turbine apparatus
US2858102A (en) * 1954-09-03 1958-10-28 Gen Electric Turbomachine wheels and methods of making the same
US3055633A (en) * 1957-04-19 1962-09-25 Pouit Robert Hot gas turbines
US3059901A (en) * 1958-04-01 1962-10-23 Carrier Corp Rotor construction
US3314649A (en) * 1963-04-15 1967-04-18 Gen Electric Turbomachine cooling system
US3314650A (en) * 1965-07-20 1967-04-18 Gen Motors Corp Cooled blade
US3330474A (en) * 1965-12-08 1967-07-11 Lister & Co Ltd R A Axial-flow blowers
US4473336A (en) * 1981-09-26 1984-09-25 Rolls-Royce Limited Turbine blades
US4854374A (en) * 1988-02-02 1989-08-08 Frank Harrison Temperature controlling apparatus
US4879880A (en) * 1989-01-17 1989-11-14 Frank Harrison Air temperature regulator
US20150093249A1 (en) * 2013-09-30 2015-04-02 MTU Aero Engines AG Blade for a gas turbine
EP3023191A1 (en) * 2014-11-20 2016-05-25 Siemens Aktiengesellschaft Turbine blade made of two parts
EP3851640A3 (en) * 2020-01-17 2021-07-28 Raytheon Technologies Corporation Rotor assemblies for a gas turbine engine
US11371351B2 (en) 2020-01-17 2022-06-28 Raytheon Technologies Corporation Multi-disk bladed rotor assembly for rotational equipment

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