EP0040267B1 - Stator refroidi pour turbines - Google Patents

Stator refroidi pour turbines Download PDF

Info

Publication number
EP0040267B1
EP0040267B1 EP80200461A EP80200461A EP0040267B1 EP 0040267 B1 EP0040267 B1 EP 0040267B1 EP 80200461 A EP80200461 A EP 80200461A EP 80200461 A EP80200461 A EP 80200461A EP 0040267 B1 EP0040267 B1 EP 0040267B1
Authority
EP
European Patent Office
Prior art keywords
guide vane
vane carrier
guide
individual
comb
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.)
Expired
Application number
EP80200461A
Other languages
German (de)
English (en)
Other versions
EP0040267A1 (fr
Inventor
Wolfgang Beckershoff
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.)
BBC Brown Boveri AG Switzerland
Original Assignee
BBC Brown Boveri AG Switzerland
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 BBC Brown Boveri AG Switzerland filed Critical BBC Brown Boveri AG Switzerland
Priority to AT80200461T priority Critical patent/ATE16035T1/de
Priority to EP80200461A priority patent/EP0040267B1/fr
Priority to DE8080200461T priority patent/DE3071161D1/de
Priority to JP6351181A priority patent/JPS5710707A/ja
Priority to US06/260,336 priority patent/US4386885A/en
Publication of EP0040267A1 publication Critical patent/EP0040267A1/fr
Application granted granted Critical
Publication of EP0040267B1 publication Critical patent/EP0040267B1/fr
Expired legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
    • F01D25/00—Component parts, details, or accessories, not provided for in, or of interest apart from, other groups
    • F01D25/24—Casings; Casing parts, e.g. diaphragms, casing fastenings
    • F01D25/243—Flange connections; Bolting arrangements
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
    • F01D25/00—Component parts, details, or accessories, not provided for in, or of interest apart from, other groups
    • F01D25/08—Cooling; Heating; Heat-insulation
    • F01D25/14—Casings modified therefor

Definitions

  • the present invention relates to a guide vane carrier for a gas turbine according to the preamble of the claim.
  • the guide vane carriers in gas turbines take over the aerodynamic forces acting on the guide vanes and transmit them to the housing, the guide vane carriers being, however, not exposed to the typical boiler voltages as the machine housing at a relatively high intrinsic temperature.
  • guide vane carriers were formed as separate parts, which made it possible for them to expand freely due to their own temperature. They are arranged in a known manner in the housing in such a way that they are advantageously fixed and sealed in the cooler parts lying downstream.
  • a gas turbine of the type mentioned at the outset is known, for example, from US Pat. No. 2,618,120, in which the coolant is guided in cooling channels which are arranged in the circumferential direction and are used alternately as supply and discharge lines. These coolant channels are arranged on the surface, so that thermal stresses can occur in the individual shells of the guide vane carrier.
  • the cooling air for the blade carrier is conducted in a channel, which is formed on the one hand by the inner wall of the blade carrier and on the other hand by an additionally inserted channel wall. After exiting the duct, the cooling air enters a duct which is closed by a casing and which covers part of the blade carrier (CH-A-425 341).
  • a connection for the two halves of a guide vane carrier of a gas turbine has become known, in which tangential screwing elements are provided in the area of the parting plane of the two housing halves, which are supported on ribs-reinforced webs. These webs form abutments for the connecting bolts which have the same diameter over the entire length and which pass through eyes in the webs.
  • This design of the connecting bolts requires relatively large distances between the individual connecting bolts, in which reinforcing ribs are arranged. With such a design, however, bending moments can occur from the thermal stresses that occur.
  • the formation of the guide vane carrier with the tapping holes branching off from the coolant channels to the individual guide vanes enables a uniform and adjustable coolant flow, as a result of which the bending moment on the partial flange is reduced to a minimum as a result of residual heat stresses in the wall.
  • the guide vane carriers preferably have a separating surface in the horizontal plane, a partial surface screw connection must be provided, which must be designed in such a way that it does not diverge during operation as a result of the bending moments that result from thermal stresses.
  • the inventive comb profile-like design of the flange screw connection of the guide vane carrier enables the partial surface flange to be screwed together by means of screws which are located in slots which are open on one side.
  • the flange material delimiting the screw slots forms rib-like projections which form the comb profile in connection with the wall of the guide vane carrier. Since each slot only needs to have the width of the screw shaft, for example the expansion shaft of an expansion screw, which has a much smaller diameter than the threaded parts thereof, the comb pitch can be kept much smaller.
  • the open slots of the air flowing around the guide vane carrier and coming out of the compressor allow these parts to flow freely, as a result of which both the flange material and the fastening screws are heated evenly, so that the otherwise usual thermal stresses in the flange zone and the expansion of the screw shafts beyond the yield point be avoided.
  • the section modulus and the overall cross-section are reinforced by the comb profiles, the slots can be made so deep that they affect the sealing strip provided. It can thus be achieved that the moment of inertia in the area of the flange corresponds to the moment of inertia over the entire circumference of the shell.
  • the groove base of the slots is semicircular, which largely eliminates the notch effect, which has an advantageous effect, particularly in the case of comb profiles welded together from bleaching parts, as a wall transition which is largely defused with respect to the notch effect, and the removal of the penetration which occurs during welding is facilitated.
  • the expansion bolts are held in nut supports, each of which bridges a slot, these nut supports with their preferably round-shaped boundary surface lying in a groove provided in parallel with the flange surface and having a semicircular cross section.
  • the outer contour of the comb-like flange plates advantageously runs almost in a straight line and the comb section, which is based on a smooth wall, results in a thickness distribution in which the material accumulations are considerably smaller than those of the known flange contours. This applies both to the cross section itself and to the existing moments of resistance. The rugged cross-sectional transitions are also missing in such a design.
  • the inlet sections can be locked in the axial direction, in such a way that massive projections of the inlet section snap into the lugs arranged on the guide vane carrier.
  • the connecting elements to the coolant channels are simultaneously brought into a positive connection with the guide vane carrier.
  • 1 and 2, 1 denotes a guide vane carrier which has a conically shaped section 2 and a cylindrical section 3, the conical section 2 having the same angle of inclination essentially over its entire length.
  • guide lugs 4 are arranged which guide the guide vane carrier 1 in the machine housing (not shown).
  • the guide lugs 4 'additionally serve to limit displacements of a hot gas housing 5 with an intermediate jacket 6 and a rib 7 serves as a spacer between these two components 10 is arranged in the cylindrical portion 3 and in a nose 11 of a locking element 12. Hollow inlet segments 13 are also attached to the locking element 12.
  • the locking element 12 also serves to guide and seal the connection of the hot gas housing 5, as well as to guide the intermediate jacket 6 and a coolant passage 14 for introducing the inlet segment cooling medium, the holder of the inlet segments 13, the holder of the first guide vane row 10, and the guide of cooling medium connecting elements 15, which are arranged between the cooling medium passage 14 and the cooling channel system of the inlet segments 13.
  • cooling channels 16 are arranged, which are charged with coolant via inlet openings 17, or from which the heated coolant flows out via outlet openings 18.
  • the inlet 17 and outlet openings 18 are alternately adjacent to one another over the circumference arranged (see also Fig. 4 and 5).
  • the cooling channels 16 are connected to the cooling channel system of the guide vanes 9, 10 via connecting channels 19.
  • the cooling channels 16 can be closed at the high-pressure end of the guide vane carrier 1 when no inlet segments 13 need to be cooled. Since the cooling channels 16 alternately supply the guide vanes 9, 10 alone and the inlet segments 13 with cooling medium alternately over the circumference of the guide vane carrier 1, the cooling channel 16 is therefore also alternately closed in pairs, or this is free for the passage of coolant 14.
  • the arrows drawn in FIGS. 1 and 2 show the direction of flow of the cooling medium.
  • the inlet segment 13 can be, for example, an end piece of an annular combustion chamber.
  • the cross section through the guide vane carrier 1 according to FIG. 4 illustrates the alternating arrangement of the supply and discharge lines of the cooling channels 16, 16 '.
  • two guide blades 9 are fastened to a common base plate 22, distribution channels 29 being arranged in each base plate in such a way that they communicate with the connecting channels 19.
  • FIGS. 1 to 4 From the top view of the guide vane carrier 1 is the arrangement of the inlet openings 17 and outlet openings 18 leading into and out of the guide vane carrier 1, which lead into the cooling channels 16 (not visible), clearly recognizable.
  • the guide lugs 4 are arranged between the inlet openings 17 and outlet openings 18.
  • the cylindrical section 3 with the lugs 4 'and coolant transfers indicated by arrows 23 to and from the (not shown) inlet segment 13 are shown.
  • Comb profile-like screw connections 24 are provided in the partial surface area of the guide vane carrier 1.
  • the cylindrical section 3 of the guide vane carrier 1 has slots 25 which cancel out the stiffening effect of the kink between the conical section 2 and the cylindrical section 3, as well as the associated bending moments on the flange screw connection in the event of temperature differences.
  • FIGS. 6, 7 and 8 show details of the partial surface screw connection, again with 1 the wall of the guide vane carrier is designated, on which a flange 26 is arranged, which is tightened with fastening screws 27, preferably with expansion screws.
  • the flanges 26 are designed in such a way that the wall of the guide vane carrier 1 is designed in the manner of a comb profile in the area between the contact surfaces of the fastening screws 27, the outwardly open slots (according to FIGS. 9 and 10) being designed such that the expansion shafts of the expansion screws fill them whereby the threaded heads of the fastening screws 27 with nut supports 28 rest on the comb profiles 24.
  • the outer contour of the comb profiles 24 runs approximately in a straight line.
  • the nut supports 28 are provided under the nuts of the expansion screws 27, which have a cylindrical underside, which in turn is in a corresponding groove simultaneously form the notch-free transition from the flange combs to the general wall and secure the screws 27 together with nuts and nut supports 28 in the screwed state against slipping out of the slot 27 from the side. Since the cylindrical bearing surfaces permit rotary movements about their cylinder axes, this configuration becomes insensitive to an inclined position of the screws 27 at least in one plane and thus permits the approval of coarser manufacturing tolerances.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Turbine Rotor Nozzle Sealing (AREA)
  • Motor Or Generator Cooling System (AREA)

Claims (4)

1. Porte-aubes directrices pour turbine à gaz, qui est en deux parties, qui est refroidi au moyen de canaux à agent de refroidissement (16, 16'), qui porte des aubes directrices refroidies et qui, concentriquement à l'axe longitudinal de la turbine, présente une configuration au moins en partie conique, des éléments de vissage disposés tangentiellement étant prévus pour joindre les deux moitiés du porte-aubes directrices dans la zone du plan de séparation et prenant appui sur des épaulements formés par des nervures disposées tangentiellement à la surface extérieure du carter, caractérisé en ce que les canaux à agent de refroidissement (16) dans la paroi du porte-aubes ont la forme de canaux d'alimentation et/ou d'évacuation (17, 18) qui alternent dans le sens circonférentiel et sont pourvus de canaux de communication avec les semelles individuelles (22) des aubes directrices (9, 10), l'agent de refroidissement étant amené à partir de ces semelles dans les aubes directrices creuses elles-mêmes, et les brides des surfaces de séparation du porte-aubes directrices (1) sont profilées en peigne, les dents (24) du peigne de l'assemblage à brides des surfaces de séparation étant formées par des nervures individuelles, et les éléments de vissage (27) étant disposés dans les fentes ouvertes d'un côté (25) qui sont prévues entre les nervures.
2. Porte-aubes directrices suivant la revendication 1, caractérisé en ce que la largeur des fentes entre les dents de peigne individuelles (24) correspond au diamètre de la tige des éléments de vissage (27).
3. Porte-aubes directrices refroidi suivant la revendication 2, caractérisé en ce que les éléments de vissage (27) sont des vis à tige allégée.
4. Porte-aubes directrices suivant la revendication 1, caractérisé en ce que la partie de tête (13) peut être verrouillée dans le sens axial au moyen de becs (4') prévus sur le porte-aubes directrices dans des saillies prévues sur cette partie de tête.
EP80200461A 1980-05-19 1980-05-19 Stator refroidi pour turbines Expired EP0040267B1 (fr)

Priority Applications (5)

Application Number Priority Date Filing Date Title
AT80200461T ATE16035T1 (de) 1980-05-19 1980-05-19 Gekuehlter leitschaufeltraeger.
EP80200461A EP0040267B1 (fr) 1980-05-19 1980-05-19 Stator refroidi pour turbines
DE8080200461T DE3071161D1 (en) 1980-05-19 1980-05-19 Cooled turbine stator
JP6351181A JPS5710707A (en) 1980-05-19 1981-04-28 Cooled guide blade holding body
US06/260,336 US4386885A (en) 1980-05-19 1981-05-04 Cooled guide support vane

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP80200461A EP0040267B1 (fr) 1980-05-19 1980-05-19 Stator refroidi pour turbines

Publications (2)

Publication Number Publication Date
EP0040267A1 EP0040267A1 (fr) 1981-11-25
EP0040267B1 true EP0040267B1 (fr) 1985-10-09

Family

ID=8186999

Family Applications (1)

Application Number Title Priority Date Filing Date
EP80200461A Expired EP0040267B1 (fr) 1980-05-19 1980-05-19 Stator refroidi pour turbines

Country Status (5)

Country Link
US (1) US4386885A (fr)
EP (1) EP0040267B1 (fr)
JP (1) JPS5710707A (fr)
AT (1) ATE16035T1 (fr)
DE (1) DE3071161D1 (fr)

Families Citing this family (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4627233A (en) * 1983-08-01 1986-12-09 United Technologies Corporation Stator assembly for bounding the working medium flow path of a gas turbine engine
JPS61173284U (fr) * 1985-04-15 1986-10-28
JPS62157377U (fr) * 1986-03-26 1987-10-06
US4907946A (en) * 1988-08-10 1990-03-13 General Electric Company Resiliently mounted outlet guide vane
DE4327376A1 (de) * 1993-08-14 1995-02-16 Abb Management Ag Verdichter sowie Verfahren zu dessen Betrieb
US5626909A (en) 1994-12-07 1997-05-06 General Electric Company Fabrication of brazable in air tool inserts
US5685693A (en) * 1995-03-31 1997-11-11 General Electric Co. Removable inner turbine shell with bucket tip clearance control
DE19546722B4 (de) * 1995-12-14 2005-03-31 Alstom Leitschaufelträger für eine Gasturbine
CN1106496C (zh) * 1996-06-21 2003-04-23 西门子公司 涡轮轴及其冷却方法
DE19643716A1 (de) 1996-10-23 1998-04-30 Asea Brown Boveri Schaufelträger für einen Verdichter
FR2761119B1 (fr) * 1997-03-20 1999-04-30 Snecma Stator de compresseur de turbomachine
CA2263508C (fr) * 1997-06-19 2003-08-19 Mitsubishi Heavy Industries, Ltd. Dispositif pour sceller des aubes de stator de turbine a gaz
GB0403198D0 (en) * 2004-02-13 2004-03-17 Rolls Royce Plc Casing arrangement
EP2148045A1 (fr) * 2008-07-25 2010-01-27 Siemens Aktiengesellschaft Section de boîtier pour une turbine à gaz
EP2159384A1 (fr) * 2008-08-27 2010-03-03 Siemens Aktiengesellschaft Support statorique d'aubes directrices pour une turbine à gaz
EP2159381A1 (fr) * 2008-08-27 2010-03-03 Siemens Aktiengesellschaft Support d'aube directrice de turbine pour une turbine à gaz
FR3101105B1 (fr) * 2019-09-23 2021-09-10 Safran Aircraft Engines Carter pour turbomachine et turbomachine équipée d’un tel carter

Family Cites Families (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE451857C (de) * 1925-01-06 1927-11-02 Bernhard Moll Dipl Ing Dampfkraftanlage, insbesondere Dampfturbine, mit Vorwaermung des Kesselspeisewassers
CH148852A (de) * 1930-07-08 1931-08-15 Escher Wyss Maschf Ag Dampf- oder Gasturbine, insbesondere für hohen Druck und hohe Temperatur.
US1938688A (en) * 1931-12-19 1933-12-12 Nanna S Brooke Gas turbine
CH202312A (de) * 1937-03-15 1939-01-15 Bbc Brown Boveri & Cie Einrichtung an mit Heissdampf betriebenen Maschinen zum raschen Anwärmen derselben.
GB510672A (en) * 1938-03-18 1939-08-04 British Thomson Houston Co Ltd Improvements in and relating to casings for elastic fluid turbines
US2489683A (en) * 1943-11-19 1949-11-29 Edward A Stalker Turbine
US2618120A (en) * 1946-06-07 1952-11-18 Papini Anthony Coaxial combustion products generator and turbine with cooling means
GB675484A (en) * 1949-02-10 1952-07-09 English Electric Co Ltd Improvements in and relating to the stator cooling of gas turbines
US3275294A (en) * 1963-11-14 1966-09-27 Westinghouse Electric Corp Elastic fluid apparatus
GB1126469A (en) * 1964-09-24 1968-09-05 English Electric Co Ltd Improvements in or relating to gas turbines
CH425341A (de) * 1965-07-23 1966-11-30 Bbc Brown Boveri & Cie Gasturbine mit Kühlung der Schaufelträger
CH467930A (de) * 1967-07-12 1969-01-31 Escher Wyss Ag Verfahren zum Betreiben einer Dampf- oder Gasturbine mit von Arbeitsmittel durchströmten Wärmeaustauschkanälen in Gehäuseteilen grösserer Materialstärke, sowie Einrichtung zur Durchführung dieses Verfahrens
US3734639A (en) * 1968-01-25 1973-05-22 Gen Motors Corp Turbine cooling
CH488931A (de) * 1968-03-22 1970-04-15 Sulzer Ag Gehäuse für Turbomaschinen, insbesondere axial getrenntes Gehäuse für Hochtemperaturturbinen
CH488098A (de) * 1968-04-10 1970-03-31 Licentia Gmbh Einrichtung zur Kühlung der Flansche an den Gehäuseteilfugen von Sattdampf- oder Nassdampfturbinen
US3736069A (en) * 1968-10-28 1973-05-29 Gen Motors Corp Turbine stator cooling control
US4184689A (en) * 1978-10-02 1980-01-22 United Technologies Corporation Seal structure for an axial flow rotary machine

Also Published As

Publication number Publication date
ATE16035T1 (de) 1985-10-15
DE3071161D1 (en) 1985-11-14
JPS5710707A (en) 1982-01-20
EP0040267A1 (fr) 1981-11-25
US4386885A (en) 1983-06-07
JPS648173B2 (fr) 1989-02-13

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