EP0894558A1 - Aube de turbine et procédé de fabrication d'un aube de turbine - Google Patents

Aube de turbine et procédé de fabrication d'un aube de turbine Download PDF

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Publication number
EP0894558A1
EP0894558A1 EP97113044A EP97113044A EP0894558A1 EP 0894558 A1 EP0894558 A1 EP 0894558A1 EP 97113044 A EP97113044 A EP 97113044A EP 97113044 A EP97113044 A EP 97113044A EP 0894558 A1 EP0894558 A1 EP 0894558A1
Authority
EP
European Patent Office
Prior art keywords
area
turbine blade
blade
turbine
wall
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP97113044A
Other languages
German (de)
English (en)
Inventor
Burkhard Bischoff-Beiermann
Winfried Esser
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Siemens AG
Original Assignee
Siemens AG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Siemens AG filed Critical Siemens AG
Priority to EP97113044A priority Critical patent/EP0894558A1/fr
Priority to PCT/EP1998/004529 priority patent/WO1999006166A1/fr
Priority to EP98943748A priority patent/EP0998361B1/fr
Priority to DE59805830T priority patent/DE59805830D1/de
Priority to JP2000504966A priority patent/JP2003520313A/ja
Publication of EP0894558A1 publication Critical patent/EP0894558A1/fr
Priority to US09/494,777 priority patent/US6257828B1/en
Withdrawn legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22C—FOUNDRY MOULDING
    • B22C9/00—Moulds or cores; Moulding processes
    • B22C9/02—Sand moulds or like moulds for shaped castings
    • B22C9/04—Use of lost patterns
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D27/00—Treating the metal in the mould while it is molten or ductile ; Pressure or vacuum casting
    • B22D27/04—Influencing the temperature of the metal, e.g. by heating or cooling the mould
    • B22D27/045—Directionally solidified castings
    • Y—GENERAL 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
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S415/00—Rotary kinetic fluid motors or pumps
    • Y10S415/915—Pump or portion thereof by casting or molding

Definitions

  • the invention relates to a turbine blade, in particular a gas turbine blade, which extends along a Major axis from a root area over an airfoil area extends to a head area.
  • the invention relates furthermore a method for producing a turbine blade, especially a gas turbine blade.
  • DE-AS 22 42 111 describes a device and a method for the production of castings, in particular gas turbine blades, described with a solidified structure.
  • the method and the device serve for the production as far as possible void-free castings.
  • the directional solidification with a single-crystal or stem-shaped structure through a Control over the beginning of grain growth reached.
  • At The process is carried out using a molten metal bowl shape to be filled placed on a quenching plate and heated to a temperature that in particular 150 ° C above the temperature of the melting point of the pouring metal.
  • the molten metal is in the Filled bowl shape and the quench plate with the bowl shape immersed in a coolant bath. The temperature the coolant is significantly below the Melting point of the metal.
  • the quench plate is already before pouring the metal into the shell mold through the Coolant cooled.
  • a superalloy as metal such as Mar-M 200 used.
  • Immersing the shell shape in the Coolant bath takes place at such a speed that the surface of the coolant bath is the solitus level not advanced, so the heat dissipation from the pulpy Zone of the solidifying alloy occurs vertically downwards and the liquid-solid interface is substantially horizontal remains. This is to ensure the growth of a single crystal and nucleation of grains on the surface prevent the shell shape.
  • the bowl shape is over Heated at 1500 ° C.
  • Liquid tin is used as the cooling liquid, which has a temperature of about 260 ° C.
  • the Speed at which the bowl shape enters the liquid bath immersed is about 3 m / h.
  • the turbine blade is used as a full material scoop made of a nickel or Cobalt based alloy in single crystal form, with a Cast total length of about 10 cm.
  • EP-0 010 538 A1 there is a speed controller
  • the ratio of temperature gradient G and rate of solidification R is of particular importance for the directional solidification of a casting.
  • the ratio of G to R must exceed a certain characteristic value in order for directional solidification to take place.
  • the directional solidification is mainly used to produce a casting for a gas turbine, which is a stalk-shaped grain structure, a single crystal or a one-dimensionally directed eutectic.
  • the directional solidification method is used for superalloys such as U-700, B-1900, Mar-M 200 and IN-100.
  • Test trials for the production of a gas turbine blade for the first stage of an aircraft engine in monocrystalline form were carried out at high immersion speeds with radiation cooling and alternatively with cooling using a liquid metal.
  • the radiation cooling speed was between 7.5 cm / h and 33 cm / h.
  • the directionally solidified casting was cast as a full body.
  • TCS formally controlled solidification
  • a casting produced by this method differs from a directionally solidified casting or a single-crystalline casting, in particular in terms of the grain size.
  • Directionally solidified and monocrystalline castings are distinguished by large and medium grain sizes, whereas a casting produced by the thermally controlled solidification process has an average grain size like a conventionally produced casting.
  • a casting made using the thermally controlled solidification process has a consistent and uniform grain size in all casting areas.
  • a ratio of temperature gradient G and solidification speed R is used, which leads to a microstructure with relatively small, rectified grains and minimal shrinkage.
  • the process is carried out in a vacuum furnace in which a casting mold is heated by means of induction heating in a heating zone and is moved out of this heating zone in order to solidify the molten metal, so that the molten metal is cooled and solidified by radiation cooling.
  • a casting mold and the construction of a corresponding furnace are described, for example, in US Pat. No. 4,724,891. This describes the production of a housing part of a turbine plant which in some areas has a thin wall structure with an area of more than 30 cm 2 and a wall thickness of less than 0.125 cm. The ratio of the area of the area with small wall thickness and the wall thickness is at least 40.
  • the object of the invention is a turbine blade, in particular to specify a turbine blade for a gas turbine. Another task is to create a process to specify a turbine blade.
  • a door bucket blade Task solved by a turbine blade that runs along a major axis from a root area over an airfoil area extends to a head area, and at least has a cavity in the airfoil area that at least in areas from a scoop wall of small wall thickness is surrounded, the blade wall being a metallic one Material with a small average grain size of the order of magnitude the grain size of a conventionally cast material having.
  • the cross-sectional area preferably increases in a plane perpendicular to the main axis from the head region to the foot region.
  • the cross-sectional area is preferably in a range between 500 mm 2 to 10,000 mm 2 .
  • the cross-sectional area can be largely constant over a predetermined length, determined in accordance with the required strengths, from the head region into the airfoil region. Further into the airfoil area in the direction of the foot area, the cross-sectional area can increase exponentially in particular.
  • the wall thickness preferably increases from the head area in the direction of the foot area. This can preferably be accompanied by the reduction in the size of the cavity.
  • the turbine blade has a direction perpendicular to the Main axis an extension, which is defined by a distance of a Inflow area is characterized by an outflow area, this distance preferably from the foot area to the head area decreases.
  • the turbine blade is preferably a moving blade or a guide vane of a gas turbine, especially a stationary one Gas turbine. It is preferably made of one Nickel-based or cobalt-based superalloy, such as CM 247LC, Rene 80, IN 792, IN 738LC or IN 939. Of course are suitable depending on the requirements of the turbine blade also other superalloys, such as those found in the literature are known.
  • the wall thickness of the blade wall preferably has a minimum value, which is between 0.5 mm and 5 mm.
  • a turbine blade is included clearly different wall thicknesses and possibly also with Areas made of solid material, in which the alloy is free of pores and voids and in the entire turbine blade largely has the same grain structure.
  • the Process can be a turbine blade with a small Produce cross-sectional profile and thus a low weight, thereby reducing the mechanical load on a Blade root, which is in a rotor of a gas turbine Anchoring is attached, and the rotor itself is reached becomes. This also achieves a turbine blade with a long airfoil area, especially for the Use in a stationary gas turbine at high temperatures of well over 1000 ° C.
  • FIG. 1 shows a longitudinal view of a turbine blade 1, which extend along a main axis 2 from a foot region 3 extends over an airfoil area 4 to a head area 5.
  • the turbine blade 1 has in the airfoil area 4 towards the head area 5 a cavity 6, so that the turbine blade 1 a Has blade wall 7 with low wall thickness in some areas.
  • the airfoil area points in the direction of the foot area 3 4 a hollow cross-section through which the cavity clear core is removable.
  • the turbine blade 1 has an inflow area 11 for inflow with a hot gas 10 (see FIG. 3) and an outflow area 9 11 and outflow area 9 are perpendicular to the main axis 2 spaced apart by a distance D. This distance D goes from the blade root area 3 to the head area 5 continuously.
  • the conventional casting process requires also a minimum wall thickness at the head area of the turbine blade, so that through the conventional casting process conditional wall thicknesses in the head area or the head area facing blade area are larger than that by the material strength actually required wall thickness.
  • the resulting additional mass in the head area leads to a strong increase in the centrifugal force in the Foot area, which is an enlargement of the Require cross section of the turbine blade in the foot area.
  • These limitations of the conventional casting process result to significantly heavier turbine blades than for reasons the strength would be required. It also takes away the weight of the turbine blade 1 and the load in the foot area 3, with which the turbine blade 1 in a rotor Gas turbine is attached as well as in the rotor itself.
  • FIG. 4 shows a detail in a longitudinal section a heating zone 15 in a vacuum furnace, not shown is arranged.
  • a mold 14 for a turbine blade 1 is shown in the heating zone 15 .
  • the mold 14 is on a support plate 17 and an induction heater 16 surrounded.
  • the mold 14 is towards the support plate 17 locked.
  • the mold 14 is heated to a temperature above of the material to be solidified therein, in particular one Nickel or cobalt based superalloy, heated.
  • the molten material is filled and then the mold at a given speed out of the induction heater 16 or the induction heater 16 at a given speed in vertical Direction moved away from the mold 14.
  • the invention is characterized by a turbine blade, which is a material, in particular a nickel or cobalt-based superalloy, has an essentially void and pore-free structure with an average grain size similar to that of a conventionally cast material.
  • the turbine blade can be controlled by a thermally controlled Solidification process also in the area of thin wall thicknesses produce.
  • the process is characterized inter alia by by that the turbine blade is also different in areas Wall thickness and in areas made of solid material essentially has the same grain structure. This allows Turbine blades for higher material temperatures and with Make the airfoil area longer than that of conventional ones Casting process. Large thin-walled ones can also be used produce hollow turbine blades.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Turbine Rotor Nozzle Sealing (AREA)
EP97113044A 1997-07-29 1997-07-29 Aube de turbine et procédé de fabrication d'un aube de turbine Withdrawn EP0894558A1 (fr)

Priority Applications (6)

Application Number Priority Date Filing Date Title
EP97113044A EP0894558A1 (fr) 1997-07-29 1997-07-29 Aube de turbine et procédé de fabrication d'un aube de turbine
PCT/EP1998/004529 WO1999006166A1 (fr) 1997-07-29 1998-07-20 Aube de turbine et son procede de fabrication
EP98943748A EP0998361B1 (fr) 1997-07-29 1998-07-20 Aube de turbine et utilisation d'un procede connu pour son fabrication
DE59805830T DE59805830D1 (de) 1997-07-29 1998-07-20 Turbinenschaufel sowie anwendung eines bekannten verfahrens zu deren herstellung
JP2000504966A JP2003520313A (ja) 1997-07-29 1998-07-20 タービン翼ならびにタービン翼の製造方法
US09/494,777 US6257828B1 (en) 1997-07-29 2000-01-31 Turbine blade and method of producing a turbine blade

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP97113044A EP0894558A1 (fr) 1997-07-29 1997-07-29 Aube de turbine et procédé de fabrication d'un aube de turbine

Publications (1)

Publication Number Publication Date
EP0894558A1 true EP0894558A1 (fr) 1999-02-03

Family

ID=8227140

Family Applications (2)

Application Number Title Priority Date Filing Date
EP97113044A Withdrawn EP0894558A1 (fr) 1997-07-29 1997-07-29 Aube de turbine et procédé de fabrication d'un aube de turbine
EP98943748A Expired - Lifetime EP0998361B1 (fr) 1997-07-29 1998-07-20 Aube de turbine et utilisation d'un procede connu pour son fabrication

Family Applications After (1)

Application Number Title Priority Date Filing Date
EP98943748A Expired - Lifetime EP0998361B1 (fr) 1997-07-29 1998-07-20 Aube de turbine et utilisation d'un procede connu pour son fabrication

Country Status (5)

Country Link
US (1) US6257828B1 (fr)
EP (2) EP0894558A1 (fr)
JP (1) JP2003520313A (fr)
DE (1) DE59805830D1 (fr)
WO (1) WO1999006166A1 (fr)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10038453A1 (de) * 2000-08-07 2002-02-21 Alstom Power Nv Verfahren zur Herstellung eines gekühlten Feingussteils
EP3699398A1 (fr) * 2019-02-21 2020-08-26 MTU Aero Engines GmbH Aube sans bandage pour un étage de turbine à haute vitesse
CN113000789A (zh) * 2021-02-23 2021-06-22 贵州安吉航空精密铸造有限责任公司 一种蜗壳状铸件铸造成型方法

Families Citing this family (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6511293B2 (en) 2001-05-29 2003-01-28 Siemens Westinghouse Power Corporation Closed loop steam cooled airfoil
EP1283325A1 (fr) * 2001-08-09 2003-02-12 Siemens Aktiengesellschaft Ailette de turbine et procédé de fabrication d'une ailette de turbine
US20040115059A1 (en) * 2002-12-12 2004-06-17 Kehl Richard Eugene Cored steam turbine bucket
US7104762B2 (en) * 2004-01-06 2006-09-12 General Electric Company Reduced weight control stage for a high temperature steam turbine
US7216694B2 (en) * 2004-01-23 2007-05-15 United Technologies Corporation Apparatus and method for reducing operating stress in a turbine blade and the like
US8740567B2 (en) * 2010-07-26 2014-06-03 United Technologies Corporation Reverse cavity blade for a gas turbine engine
IT1401661B1 (it) * 2010-08-25 2013-08-02 Nuova Pignone S R L Forma di profilo areodinamico per compressore.
ITCO20110060A1 (it) * 2011-12-12 2013-06-13 Nuovo Pignone Spa Turbina a vapore, paletta e metodo
US8720526B1 (en) * 2012-11-13 2014-05-13 Siemens Energy, Inc. Process for forming a long gas turbine engine blade having a main wall with a thin portion near a tip
EP3511522A1 (fr) * 2018-01-11 2019-07-17 Siemens Aktiengesellschaft Aube de turbine à gaz et procédé de production d'une telle aube

Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE717865C (de) * 1939-01-27 1942-02-25 Bmw Flugmotorenbau Ges M B H Hohlschaufel fuer Abgasturbinenraeder aus zwei miteinander verschweissten Teilen
DE757189C (de) * 1937-12-23 1954-04-05 Bayerische Motoren Werke Ag Hohlschaufel
DE1007565B (de) * 1956-05-03 1957-05-02 Holzwarth Gasturbinen G M B H Hohle Turbinenschaufel fuer in Axialrichtung von gasfoermigen Treibmitteln beaufschlagte Turbinen
US2916258A (en) * 1956-10-19 1959-12-08 Gen Electric Vibration damping
US3465812A (en) * 1965-09-23 1969-09-09 Martin Marietta Corp Heater bar system
DE2242111A1 (de) 1971-09-15 1973-03-22 United Aircraft Corp Verfahren und vorrichtung zum giessen von gegenstaenden mit gerichtet erstarrtem gefuege
EP0010538A1 (fr) 1978-10-25 1980-04-30 United Technologies Corporation Méthode de solidification directionnelle à vitesse contrôlée et article produit selon cette méthode
US4724891A (en) 1985-12-24 1988-02-16 Trw Inc. Thin wall casting
US5072771A (en) * 1988-03-28 1991-12-17 Pcc Airfoils, Inc. Method and apparatus for casting a metal article
EP0750956A2 (fr) * 1992-02-18 1997-01-02 General Motors Corporation Procédé pour la production des structures coulées, à paroi mince avec une résistance à chaud élevée

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3867068A (en) * 1973-03-30 1975-02-18 Gen Electric Turbomachinery blade cooling insert retainers
CH602330A5 (fr) * 1976-08-26 1978-07-31 Bbc Brown Boveri & Cie
US5299418A (en) * 1992-06-09 1994-04-05 Jack L. Kerrebrock Evaporatively cooled internal combustion engine
DE69423061T2 (de) * 1993-08-06 2000-10-12 Hitachi Ltd Gasturbinenschaufel, Verfahren zur Herstellung derselben sowie Gasturbine mit dieser Schaufel
US5480285A (en) * 1993-08-23 1996-01-02 Westinghouse Electric Corporation Steam turbine blade
JP3209099B2 (ja) * 1996-07-08 2001-09-17 三菱マテリアル株式会社 鋳造装置、鋳造方法およびタービン翼
US5980209A (en) * 1997-06-27 1999-11-09 General Electric Co. Turbine blade with enhanced cooling and profile optimization

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE757189C (de) * 1937-12-23 1954-04-05 Bayerische Motoren Werke Ag Hohlschaufel
DE717865C (de) * 1939-01-27 1942-02-25 Bmw Flugmotorenbau Ges M B H Hohlschaufel fuer Abgasturbinenraeder aus zwei miteinander verschweissten Teilen
DE1007565B (de) * 1956-05-03 1957-05-02 Holzwarth Gasturbinen G M B H Hohle Turbinenschaufel fuer in Axialrichtung von gasfoermigen Treibmitteln beaufschlagte Turbinen
US2916258A (en) * 1956-10-19 1959-12-08 Gen Electric Vibration damping
US3465812A (en) * 1965-09-23 1969-09-09 Martin Marietta Corp Heater bar system
DE2242111A1 (de) 1971-09-15 1973-03-22 United Aircraft Corp Verfahren und vorrichtung zum giessen von gegenstaenden mit gerichtet erstarrtem gefuege
EP0010538A1 (fr) 1978-10-25 1980-04-30 United Technologies Corporation Méthode de solidification directionnelle à vitesse contrôlée et article produit selon cette méthode
US4724891A (en) 1985-12-24 1988-02-16 Trw Inc. Thin wall casting
US5072771A (en) * 1988-03-28 1991-12-17 Pcc Airfoils, Inc. Method and apparatus for casting a metal article
EP0750956A2 (fr) * 1992-02-18 1997-01-02 General Motors Corporation Procédé pour la production des structures coulées, à paroi mince avec une résistance à chaud élevée

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10038453A1 (de) * 2000-08-07 2002-02-21 Alstom Power Nv Verfahren zur Herstellung eines gekühlten Feingussteils
US6435256B1 (en) 2000-08-07 2002-08-20 Alstom (Switzerland) Ltd Method for producing a cooled, lost-wax cast part
EP3699398A1 (fr) * 2019-02-21 2020-08-26 MTU Aero Engines GmbH Aube sans bandage pour un étage de turbine à haute vitesse
US11788415B2 (en) 2019-02-21 2023-10-17 MTU Aero Engines AG Shroudless blade for a high-speed turbine stage
CN113000789A (zh) * 2021-02-23 2021-06-22 贵州安吉航空精密铸造有限责任公司 一种蜗壳状铸件铸造成型方法

Also Published As

Publication number Publication date
EP0998361A1 (fr) 2000-05-10
EP0998361B1 (fr) 2002-10-02
DE59805830D1 (de) 2002-11-07
US6257828B1 (en) 2001-07-10
WO1999006166A1 (fr) 1999-02-11
JP2003520313A (ja) 2003-07-02

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