CN105507956B - 蒸汽涡轮密封套装置 - Google Patents

蒸汽涡轮密封套装置 Download PDF

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CN105507956B
CN105507956B CN201510659945.9A CN201510659945A CN105507956B CN 105507956 B CN105507956 B CN 105507956B CN 201510659945 A CN201510659945 A CN 201510659945A CN 105507956 B CN105507956 B CN 105507956B
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sealing
steamturbine
shroud
turbine
heat shield
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CN105507956A (zh
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F.桑泰斯
L.亚斯塞特
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General Electric Technology GmbH
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Alstom Technology AG
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    • 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
    • F01D11/00—Preventing or minimising internal leakage of working-fluid, e.g. between stages
    • 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
    • F01D11/00—Preventing or minimising internal leakage of working-fluid, e.g. between stages
    • F01D11/003—Preventing or minimising internal leakage of working-fluid, e.g. between stages by packing rings; Mechanical seals
    • 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
    • F01D11/00—Preventing or minimising internal leakage of working-fluid, e.g. between stages
    • F01D11/001—Preventing or minimising internal leakage of working-fluid, e.g. between stages for sealing space between stator blade and rotor
    • 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
    • F01D25/26—Double casings; Measures against temperature strain in casings
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01K—STEAM ENGINE PLANTS; STEAM ACCUMULATORS; ENGINE PLANTS NOT OTHERWISE PROVIDED FOR; ENGINES USING SPECIAL WORKING FLUIDS OR CYCLES
    • F01K23/00—Plants characterised by more than one engine delivering power external to the plant, the engines being driven by different fluids
    • F01K23/02—Plants characterised by more than one engine delivering power external to the plant, the engines being driven by different fluids the engine cycles being thermally coupled
    • F01K23/06—Plants characterised by more than one engine delivering power external to the plant, the engines being driven by different fluids the engine cycles being thermally coupled combustion heat from one cycle heating the fluid in another cycle
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01K—STEAM ENGINE PLANTS; STEAM ACCUMULATORS; ENGINE PLANTS NOT OTHERWISE PROVIDED FOR; ENGINES USING SPECIAL WORKING FLUIDS OR CYCLES
    • F01K23/00—Plants characterised by more than one engine delivering power external to the plant, the engines being driven by different fluids
    • F01K23/02—Plants characterised by more than one engine delivering power external to the plant, the engines being driven by different fluids the engine cycles being thermally coupled
    • F01K23/06—Plants characterised by more than one engine delivering power external to the plant, the engines being driven by different fluids the engine cycles being thermally coupled combustion heat from one cycle heating the fluid in another cycle
    • F01K23/10—Plants characterised by more than one engine delivering power external to the plant, the engines being driven by different fluids the engine cycles being thermally coupled combustion heat from one cycle heating the fluid in another cycle with exhaust fluid of one cycle heating the fluid in another cycle
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02C—GAS-TURBINE PLANTS; AIR INTAKES FOR JET-PROPULSION PLANTS; CONTROLLING FUEL SUPPLY IN AIR-BREATHING JET-PROPULSION PLANTS
    • F02C7/00—Features, components parts, details or accessories, not provided for in, or of interest apart form groups F02C1/00 - F02C6/00; Air intakes for jet-propulsion plants
    • F02C7/28—Arrangement of seals
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
    • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
    • F05D2220/00—Application
    • F05D2220/30—Application in turbines
    • F05D2220/31—Application in turbines in steam turbines
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
    • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
    • F05D2240/00—Components
    • F05D2240/10—Stators
    • F05D2240/15—Heat shield
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
    • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
    • F05D2240/00—Components
    • F05D2240/60—Shafts
    • F05D2240/63—Glands for admission or removal of fluids from shafts
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
    • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
    • F05D2300/00—Materials; Properties thereof
    • F05D2300/10—Metals, alloys or intermetallic compounds
    • F05D2300/17—Alloys
    • F05D2300/171—Steel alloys

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Turbine Rotor Nozzle Sealing (AREA)

Abstract

一种用于防止蒸汽从涡轮转子(10)周围泄漏的蒸汽涡轮密封套密封装置，该密封套密封装置包括形成于附连到壳体构件(14)上的密封套支架(12)中的腔室(26)，以及使腔室(26)与构件(14)隔开的隔热罩。

Description

蒸汽涡轮密封套装置
技术领域
本公开大体涉及蒸汽涡轮，且更具体而言，涉及迷宫型的多压力蒸汽涡轮密封套(gland)装置，其用于减少蒸汽涡轮的旋转和固定构件之间的蒸汽泄漏。
背景技术
在蒸汽涡轮中，涡轮驱动蒸汽向外的泄漏典型地由密封套密封系统防止。该系统典型地包括在转子离开涡轮壳体处的区域中沿着涡轮转子定位的一连串至少三个迷宫填密段。支承密封环的密封套支架壳体可与涡轮壳体形成至少两个腔室。当在上游的更高压力的腔室中存在不只一个腔室时，腔室（一个或多个）使得能够排出蒸汽-空气的混合物以及蒸汽喷射。这些腔室中的各个由密封环或迷宫填密段分开。
具有不少于两个腔室的系统可例如包括：第一腔室，蒸汽/空气混合物喷入其中；以及第二腔室，其中取决于运行模式，蒸汽或者被喷入，或者被排出。例如，第一腔室可以大约0.95巴(bar)的压力运行，而第二腔室可以大约1.15巴的压力运行。
在典型的布置中，填密段中的各个安装在涡轮的密封套支架壳体上。在密封环安装于其上的密封套支架壳体构件另外形成蒸汽涡轮排气装置的部分的情况下，涡轮壳体构件可曝露于局部密封套腔室温度以及蒸汽涡轮排气温度。在高压蒸汽涡轮和中压蒸汽涡轮具有高压轴端密封套系统和中压轴端密封套系统的情况下，温度梯度在高压侧上可为110˚C，而在中压侧上为70˚C。这可导致涡轮壳体构件曝露于大的热应力。
发明内容
公开了一种蒸汽涡轮密封套密封装置，其可提供减小密封段安装于其上的涡轮壳体构件中的热应力的措施，从而通过减小由于涡轮排气与密封套排气腔室之间的蒸汽温度差而产生的壳体末端中的热应力，来改进例如典型的蒸汽涡轮壳体的上部和下部联接在一起所处的典型水平联接平面的紧密性。
尝试借助于独立权利要求的主题来解决该问题。从属权利要求中给出了有利的实施例。
本公开基于在形成于密封套支架与涡轮壳体构件之间且由它们形成的腔室中提供隔热罩的总体构思。隔热罩布置成使得避免了涡轮壳体构件与腔室中的蒸汽流的直接接触。这样，产生了热隔离罩与壳体的内表面之间的空间。该空间起到隔离件的作用，从而避免了水平的上半部和下半部联接法兰的局部冷却，从而减小了联接变形，这又可能有改进联接紧密性的效果。
一方面提供了用于防止蒸汽从涡轮转子周围泄漏的蒸汽涡轮密封套密封装置。该密封套密封装置包括构造成蒸汽涡轮排气装置的一部分的涡轮壳体构件，密封套支架以及在涡轮轴向方向上相邻地顺序安装在密封套支架上、以便沿转子的涡轮轴向方向进行密封的多个密封段。
该壳体构件和密封套支架构造和布置成使得形成了至少两个腔室，其中，腔室包括隔热罩，其延伸来隔开腔室。
一方面，隔热罩螺栓连接到密封套支架上。
另一方面，隔热罩由不锈钢制成。
结合附图，从以下描述中，本公开的其它方面和优点将变得显而易见，附图以示例的方式显示了本发明的示例性实施例。
附图说明
以示例的方式，在下文中参照附图更全面地描述了本公开的一个实施例，在附图中：
图1是根据本公开的优选实施例的蒸汽涡轮密封套密封装置的截面图。
具体实施方式
现在参照附图描述本公开的一个示例性实施例，其中始终使用相似的参考标号表示相似的元件。在以下描述中，为了解释的目的，阐述了许多具体细节来提供对本公开的全面的理解。然而，本公开可在没有这些具体细节的情况下实施，并且不局限于本文所公开的示例性实施例。
图1中所示的示例性蒸汽涡轮密封套密封装置安装在涡轮转子10周围。该密封套密封装置包括涡轮壳体构件14，安装在该涡轮壳体构件14上的密封套支架12，由涡轮壳体构件14和该密封套支架12形成的腔室，以及形成于涡轮壳体构件14和密封套支架12之间的隔热罩16。
涡轮壳体构件14可构造为蒸汽涡轮排气装置22的一部分。也即，涡轮壳体构件14可构造为部分地位于蒸汽膨胀所处的涡轮叶片下游的蒸汽涡轮流动路径区域中。虽然在一个示例性实施例中，涡轮壳体构件14由单个零件制成，但在另一个示例性实施例中，涡轮壳体构件14由若干零件制成，它们以使得能够通过涡轮壳体构件14进行热传导的方式粘结、联接或焊接在一起。
在图1中所示的示例性实施例中，密封套支架12是密封承载部件，其目的是承载一个或多个具有密封特征―诸如密封刷和/或迷宫翅片―的密封环。如图1中所示，在一个示例性实施例中，多个密封环13相邻地在涡轮轴向方向28上顺序地安装，优选可动地安装在密封套支架12上、涡轮壳体构件14与涡轮转子10之间。密封环13中的各个沿着涡轮转子10在涡轮轴向方向28上顺序地相邻地定位，以便在密封装置的蒸汽侧24与空气侧20之间提供密封措施。
如图1所示，在一个示例性实施例中，密封套支架12以这样的方式构造：即，使得在密封套支架12中形成面向涡轮壳体构件14的腔室26。在一个示例性实施例中，腔室26构造为以受控的压力排出其它喷射蒸汽的蒸汽/空气混合物。
在图1中所示的示例性实施例中，至少一个腔室26包括覆盖该腔室26或各个腔室26的隔热罩16，以便使腔室26与涡轮壳体构件14隔开。隔热罩16的目的是要以这样的方式隔开腔室26：即，存在流过该腔室26或各个腔室26的蒸汽或蒸汽/空气的最小的接触，从而最小化对涡轮壳体构件14的热能传递。这可通过在基本涡轮轴向方向28上延伸跨过腔室26的隔热罩16来实现。
隔热罩16最适于由可减小热曝露并且抗侵蚀的材料制成。在一个示例性实施例中，隔热罩16由不锈钢制成。
虽然已经在本文中以被认为是最实用的示例性实施例的内容显示和描述了本公开，但其可以其它具体的形式来实施。因此在各个方面认为当前所公开的实施例是示意性的而非限制性的。本公开的范围由所附的权利要求而不是之前的描述来指示，且落在其含义及范围与等效物内的所有改变都意图包括在其中。
参考标号：
10 转子
12 密封套支架
13 密封环
14 涡轮壳体构件
16 隔热罩
18 螺栓
20 空气侧
22 涡轮排气装置
24 蒸汽侧
26 腔室
28 涡轮轴向方向。

Claims (6)

1.一种用于防止蒸汽从涡轮转子(10)周围泄漏的蒸汽涡轮密封套密封装置，所述密封套密封装置包括：
蒸汽涡轮排气装置的涡轮壳体构件(14)；
安装在所述涡轮壳体构件(14)上的密封套支架(12)，其具有在涡轮轴向方向(28)上顺序地布置的多个密封环(13)，以便沿着所述涡轮转子(10)的涡轮轴向方向(28)进行密封；
形成于所述密封套支架(12)中的面向所述涡轮壳体构件(14)并构造为喷射蒸汽和空气的混合物的至少两个腔室(26)；以及
隔热罩(16)，所述隔热罩(16)布置成对应覆盖所述腔室(26)；
并且其中所述多个密封环(13)可动地安装在密封套支架上并在涡轮转子和隔热罩之间。
2.根据权利要求1所述的蒸汽涡轮密封套密封装置，其特征在于，所述隔热罩(16)在涡轮轴向方向(28)上延伸。
3.根据权利要求1所述的蒸汽涡轮密封套密封装置，其特征在于，所述隔热罩(16)包括构造和布置成将所述隔热罩(16)附连到所述密封套支架(12)上的螺栓(18)。
4.根据权利要求1所述的蒸汽涡轮密封套密封装置，其特征在于，所述隔热罩(16)由不锈钢制成。
5.根据权利要求1所述的蒸汽涡轮密封套密封装置，其特征在于，包括三个腔室(26)，其中所述三个腔室(26)中的各个腔室(26)包括所述隔热罩(16)。
6.根据权利要求1-5中的任一项所述的蒸汽涡轮密封套密封装置，其特征在于，所述涡轮壳体构件(14)和所述密封套支架(12)形成蒸汽涡轮排气装置(22)的部分。
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US9915160B2 (en) 2018-03-13
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US20160102569A1 (en) 2016-04-14
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