EP0122872B1 - Turbine de vapeur de moyenne pression pour une installation de vapeur de haute température avec réchauffage intermédiaire - Google Patents

Turbine de vapeur de moyenne pression pour une installation de vapeur de haute température avec réchauffage intermédiaire Download PDF

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Publication number
EP0122872B1
EP0122872B1 EP84730019A EP84730019A EP0122872B1 EP 0122872 B1 EP0122872 B1 EP 0122872B1 EP 84730019 A EP84730019 A EP 84730019A EP 84730019 A EP84730019 A EP 84730019A EP 0122872 B1 EP0122872 B1 EP 0122872B1
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EP
European Patent Office
Prior art keywords
rotor
cooling
steam turbine
steam
medium pressure
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
EP84730019A
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German (de)
English (en)
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EP0122872A1 (fr
Inventor
Klaus Dr.-Ing. Raschke
Gerhard Exner
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.)
Kraftwerk Union AG
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Kraftwerk Union 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 Kraftwerk Union AG filed Critical Kraftwerk Union AG
Publication of EP0122872A1 publication Critical patent/EP0122872A1/fr
Application granted granted Critical
Publication of EP0122872B1 publication Critical patent/EP0122872B1/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
    • F01D5/00—Blades; Blade-carrying members; Heating, heat-insulating, cooling or antivibration means on the blades or the members
    • F01D5/02—Blade-carrying members, e.g. rotors
    • F01D5/08—Heating, heat-insulating or cooling means
    • F01D5/081—Cooling fluid being directed on the side of the rotor disc or at the roots of the blades
    • F01D5/084—Cooling fluid being directed on the side of the rotor disc or at the roots of the blades the fluid circulating at the periphery of a multistage rotor, e.g. of drum type
    • 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
    • F01D5/00—Blades; Blade-carrying members; Heating, heat-insulating, cooling or antivibration means on the blades or the members
    • F01D5/02—Blade-carrying members, e.g. rotors
    • F01D5/08—Heating, heat-insulating or cooling means

Definitions

  • the invention relates to an MD steam turbine in a single-flow design for a high-temperature steam turbine system with reheating, which is fed through bores in the housing of the inflow part cooling steam to an annular space above the rotor surface, which is delimited on the outside by a guide plate on one Side in front of the stuffing box and on the other side ends at an extension of the first guide vanes that forms the shaft seal, the rotor blades, at least of the first rows, being provided with axial channels lying above the rotor surface, which channels the further annular spaces between the shaft seal of the adjacent guide vanes and the Connect the rotor surface together.
  • Such an MD steam turbine which is supplied with cooling steam for rotor cooling and which is removed from the reheater before reheating, is known from W. Traupel "Thermal Turbomachinery", Volume 11, 2nd Edition, 1968, pages 341/342.
  • the cooling steam is introduced into an annular space adjacent to the stuffing box, formed by cutouts in the housing of the inflow part and of the rotor, and is also partly used as sealing steam.
  • the guide plate which runs closely along the rotor surface, separates an area from the free inflow space for the working steam in the inflow part and conducts part of the cooling steam along the rotor surface to below the approach of the first guide vanes forming the shaft seal, at which the guide plate ends.
  • the cooling steam thus reaches the area of the first rows of blades.
  • the incoming steam which is hotter than the cooling steam at 583 ° C, already releases heat to the cooling steam so that it heats up before it reaches the blades.
  • the blade roots of the first two rotor blade rows are provided with axial channels lying above the rotor surface, so that the cooling steam forms a somewhat cooler underflow up to the region of the third guide blade and the temperatures of the rotor surface are reduced at these highly stressed points.
  • a ferritic material can also be used for the rotor in high-temperature steam turbines instead of the austenitic steel, which is unfavorable for thermal expansion and production.
  • the cooling steam in this area is strongly heated, especially since the heat transfer takes place in metal alone.
  • the cooling steam is therefore already preheated before it hits the first row of blades. Since the cooling channels provided only under the first row of blades are milled under the root of the blade and are not drilled, it is difficult for the cooling steam to enter this column and only a small proportion of the preheated cooling steam is passed on to the second row of guide blades. In this steam turbine, too, the cooling steam is not optimally used.
  • CH-A-311370 describes a gas turbine, the rotor body of which is composed of paddle wheels and washers. These each contain axial cooling bores, which run in the blade wheels under the blade roots and which connect adjacent rows of blades in the intermediate disks. Between the cooling holes are on the end faces of the show. rock wheels each ring spaces. From an end face of the rotor body, cooling gases are fed from a further annular space to the axial cooling bores, which are then guided in the axial cooling bores approximately parallel to the rotor surface, and are also distributed between the cooling bores in the annular spaces. The cooling gases then emerge from the other end of the rotor body and mix with the propellant gas. By means of this cooling arrangement, the temperature of the rotor body in the region of the blade roots is kept considerably lower than the high operating temperature of the propellant gas.
  • the object of the invention is to increase the effect of the additional cooling steam in an MD steam turbine of the type described in the introduction and to further reduce the thermal stress on the rotor on the first rows of blades, so that the advantage of using ferritic or martensitic materials even with higher ones Maintain live steam temperatures.
  • the MD steam turbine is designed according to the invention so that a wall of the inflow part is guided up to the shaft seal of the first guide vane and carries the guide plate on its surface facing the rotor that the rotor body contains axial cooling bores which, at least for the first rows, a connection produce between the annular space and the blade roots of adjacent rows of blades, and that connecting blades are provided on each blade of these rows in the blade feet, which connect the cooling bores to the axial channels.
  • the stiffness of the rotor also improves due to the low temperature which is present over a relatively wide area of the rotor (from the third row of rotor blades to the exit of the stuffing box). This results in a more favorable location of the critical bending speed with a thicker rotor body than would be possible using austenitic steel. Due to the improved rotor stability (gap excitation and oil film excitation), the blading structure can also be made more efficient in terms of efficiency even with a chamber turbine.
  • This special cooling of the MD steam turbine part can be used both in stationary systems and in ship turbines in order to improve the process efficiency with the help of higher live steam temperatures.
  • ship turbines as high-speed and small machines with relatively high load change speeds and speed changes, it is particularly advantageous because of the higher safety. to cool the rotor and thus to design it in ferritic or martensitic steel instead of austenitic steel in order to remain within the range of the permissible thermal stresses.
  • the axial channels and the connecting channels in the blade roots of the rotor blades can each be designed as bores. However, it is expedient to design these as lateral, open cutouts because they can then be produced in a simple manner by milling. It is also recommended; arrange the bores for the introduction of the cooling steam in the lower joint flanges of the housing and the inflow part, since the lines do not have to be opened when the upper part of the housing is uncovered.
  • FIGS. 1 to 4 each show parts of a longitudinal section of an MD steam turbine designed according to the invention.
  • Fig. 3 is a view of the first blade row of this MD steam turbine is partially shown.
  • 4 shows a part of a radial section through the flanges of the housing and the inflow part.
  • the MD steam turbine of a high-temperature steam turbine system with reheating which is used as a marine turbine, is designed in a single-flow chamber design.
  • the housing 1 with the inflow part 2 surrounds the rotor 3 designed as a drum rotor.
  • the rotor carries six rows of rotor blades 4, in front of which there is a guide vane base 5 fastened in the housing 1.
  • Each guide vane base 5 is provided on the side facing the rotor surface 6 with a shaft seal 7 which extends to the adjacent rotor blade 4 and thus delimits an annular space 8 above the rotor surface 6.
  • the blades 4 are inserted with their blade feet 9 in grooves 10 of the rotor 3.
  • the wall 11 of the inflow part 2 is guided up to the shaft seal 7 of the guide vane base 5 of the first row.
  • the stuffing box 12 lies on the other side of the inflow part 2.
  • the working steam supplied to the MD steam turbine from the reheater has a very high temperature, e.g. B. 600 ° C.
  • a very high temperature e.g. B. 600 ° C.
  • the part that first comes into contact with the hot steam such as the wall 11 of the inflow part 2, the first guide vane bottoms 5 and the first rows of the rotor blades 4 and the rotor region there, are subjected to very great stress. So that the heating occurring there can still be absorbed in a permissible manner with ferritic or martensitic materials, separate cooling with cooling steam is provided there, which is removed after exiting the high-pressure turbine in front of the reheater.
  • This cooling steam is introduced via a controllable reducing valve (not shown) via bores 13 which are introduced into the lower part-joint flanges 14 of the housing 15 of the lower inflow part 2 in an annular channel 16 which is open to the rotor 3.
  • the lower housing 15 and the wall of the inflow part 2 there support on their surface 17 facing the rotor 3 a guide plate 18 which has openings 19 in the area of the annular channel 16 for the passage of the cooling steam.
  • This guide plate 18 extends on one side to the stuffing box 12 and ends on the other side at the shaft seal 7 of the first guide vane base 5. It delimits an annular space 20 above the rotor surface 6.
  • the cooling steam flowing into the annular space 20 via the ring channel 16 is divided there into the actual cooling steam flow for cooling the active rotor section and into the sealing steam for the stuffing box 12.
  • the cooling steam is distributed over the entire circumference of the housing or rotor through the ring channel 16 . It forms in the annulus. 20 a cold vapor curtain that flows over the rotor surface 6. Since the guide plate 18 is brought close to the rotor surface 6, the cooling steam in the annular space 20 is accelerated in the circumferential direction and set in rotation.
  • the rotor 3 of the MD steam turbine contains, evenly distributed over the circumference, axial cooling bores 21, which lie at the height of the blade feet 9 of the rotor blades 4 and connect the two first rows to one another.
  • the blade feet 9 of each blade 4 are provided with laterally lying, radially directed cutouts 22 which open into axial channels 23 which lie above the rotor surface 6 and which connect the annular spaces 8 between the shaft seal 7 of the adjacent guide blade bases 5 and the rotor surface 6 .
  • These axial channels 23 also take on the task of the compensation bores customary in a chamber turbine. Therefore, the other rows also have corresponding axial channels 24 in the rotor blades 4.
  • cooling steam located in the annular space 20 in front of the first guide vane base 5 enters the annular spaces 8 below the shaft seal 7 of the guide vane bases 5 and flows along the rotor surface 6.
  • Another part of the cooling steam enters the axial cooling bores 21 and is fed to the blade roots 9 of the first two rows of the blades 4.
  • the cooling steam is distributed along the rotor grooves 10 around the entire circumference of the rotor 3 and passes into the radially directed connection channels 22 present in each rotor blade 4, from which the cooling steam flows into the axial channels 23 flows and combines there again with the other cooling steam.
  • cooling of the blade roots 9 of the rotor blades 4 and the adjacent rotor part is also achieved in this way.
  • the distribution of the cooling steam flows depends on the dimensioning of the cross sections of the axial cooling bores 21 and the shaft seal 7 and on their manufacturing accuracy.
  • the cross sections and pressure ratios are chosen so that the cooling effect after the second row of blades 4 is only slight and mixing with the active working steam has taken place without the transition of the cooling taking place in the annular spaces 8.
  • steam in the working steam produces a secondary flow which adversely affects the efficiency.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Turbine Rotor Nozzle Sealing (AREA)

Claims (4)

1. Turbine à vapeur à moyenne pression du type de construction à un seul flux pour une installation de turbine à vapeur à haute température avec resurchauffe, à laquelle, par l'intermédiaire de perçages (13) ménagées dans l'enveloppe externe (1) de la partie admission (2), est envoyée de la vapeur de refroidissement à une chambre annulaire (20) située au-dessus de la surface du rotor (6) et délimitée vers l'extérieur par une tôle de guidage (18) qui se termine, sur un côté, à l'avant du presse-étoupe (12), et sur l'autre côté au niveau d'un appendice des premières aubes directrices (5), qui constitue la garniture étanche de l'arbre (7), les aubes mobiles (4) d'au moins la première rangée étant pourvues de canaux axiaux (23) se situant au-dessus de la surface de rotor (6) et reliant les autres chambres annulaires (8), situées entre la garniture d'étanchéité de l'arbre (7) des aubes directrices voisines (5) et la surface du rotor (6), caractérisée par le fait qu'une paroi (11) de la partie admission (2) s'étend jusqu'à la garniture d'étanchéité (7) des premières aubes directrices et porte la tôle de guidage (18) sur sa surface (17) voisine du rotor (3), que le corps de rotor (3) présente des perçages axiaux de refroidissement (21) qui établissent, au moins dans les premières rangées, une liaison entre la chambre annulaire (20) et les pieds (9) des aubes de rangées voisines d'aubes mobiles (4), et qu'à chaque aube mobile (4) de ces rangées sont prévus, dans les pieds des aubes (9), des canaux radiaux de liaison (22) qui relient les perçages de refroidissement (21) aux canaux axiaux.
2. Turbine à vapeur à moyenne pression selon la revendication 1, caractérisée par le fait que les perçages (13) pour l'introduction de la vapeur de refroidissement sont disposés dans les flaques d'assemblage partiels inférieures de l'enveloppe (15) de la partie admission.
3. Turbine à vapeur à moyenne pression selon la revendication 1 ou 2, caractérisée par le fait que les canaux axiaux (23) et les canaux de liaison (9) sont réalisés dans les pieds des aubes sous la forme d'évidements latéraux ouverts.
4. Turbine à vapeur à moyenne pression selon une ou plusieurs des revendications 1 à 3, caractérisée par le fait que la turbine à vapeur à moyenne pression est réalisée sous la forme d'une turbine à cellules.
EP84730019A 1983-03-18 1984-03-08 Turbine de vapeur de moyenne pression pour une installation de vapeur de haute température avec réchauffage intermédiaire Expired EP0122872B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3310396 1983-03-18
DE3310396A DE3310396A1 (de) 1983-03-18 1983-03-18 Md-dampfturbine in einflutiger bauweise fuer eine hochtemperaturdampfturbinenanlage mit zwischenueberhitzung

Publications (2)

Publication Number Publication Date
EP0122872A1 EP0122872A1 (fr) 1984-10-24
EP0122872B1 true EP0122872B1 (fr) 1987-03-04

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EP84730019A Expired EP0122872B1 (fr) 1983-03-18 1984-03-08 Turbine de vapeur de moyenne pression pour une installation de vapeur de haute température avec réchauffage intermédiaire

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US (1) US4551063A (fr)
EP (1) EP0122872B1 (fr)
DE (2) DE3310396A1 (fr)

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KR19990077142A (ko) * 1996-01-11 1999-10-25 피터 토마스 내부 냉각되는 증기 터빈 샤프트
EP0926311B1 (fr) * 1997-12-24 2003-07-09 ALSTOM (Switzerland) Ltd Rotor pour une turbomachine
EP1242729B1 (fr) * 1999-12-21 2005-02-16 Siemens Aktiengesellschaft Procede permettant de faire fonctionner une turbine a vapeur, ainsi qu'ensemble turbine dote d'une turbine a vapeur fonctionnant selon ledit procede
US6364613B1 (en) * 2000-08-15 2002-04-02 General Electric Company Hollow finger dovetail pin and method of bucket attachment using the same
US7488153B2 (en) * 2002-07-01 2009-02-10 Alstom Technology Ltd. Steam turbine
EP1378630A1 (fr) * 2002-07-01 2004-01-07 ALSTOM (Switzerland) Ltd Turbine à vapeur
EP1452688A1 (fr) * 2003-02-05 2004-09-01 Siemens Aktiengesellschaft Rotor pour une turbine à vapeur, procédé et utilisation de refroidissement d'un tel rotor
US20070065273A1 (en) * 2005-09-22 2007-03-22 General Electric Company Methods and apparatus for double flow turbine first stage cooling
US8105032B2 (en) * 2008-02-04 2012-01-31 General Electric Company Systems and methods for internally cooling a wheel of a steam turbine
US8376687B2 (en) * 2009-10-13 2013-02-19 General Electric Company System and method for cooling steam turbine rotors
US8348608B2 (en) * 2009-10-14 2013-01-08 General Electric Company Turbomachine rotor cooling
US8662826B2 (en) * 2010-12-13 2014-03-04 General Electric Company Cooling circuit for a drum rotor
US8668439B2 (en) 2011-03-24 2014-03-11 General Electric Company Inserts for turbine cooling circuit
US8888436B2 (en) 2011-06-23 2014-11-18 General Electric Company Systems and methods for cooling high pressure and intermediate pressure sections of a steam turbine
US8899909B2 (en) 2011-06-27 2014-12-02 General Electric Company Systems and methods for steam turbine wheel space cooling
US20130280048A1 (en) * 2012-04-19 2013-10-24 General Electric Company Seal for a turbine system
US9702261B2 (en) * 2013-12-06 2017-07-11 General Electric Company Steam turbine and methods of assembling the same
CN108397247B (zh) * 2018-04-09 2024-04-12 金通灵科技集团股份有限公司 一种快装式高速同轴中间再热轴向排汽型汽轮机

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Also Published As

Publication number Publication date
US4551063A (en) 1985-11-05
DE3462536D1 (en) 1987-04-09
DE3310396A1 (de) 1984-09-20
EP0122872A1 (fr) 1984-10-24

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