JP2011137512A

JP2011137512A - Seal device

Info

Publication number: JP2011137512A
Application number: JP2009297812A
Authority: JP
Inventors: Kazuaki Muta; 和彰牟田; Kenju Nakamura; 建樹中村
Original assignee: Hitachi Ltd
Current assignee: Hitachi Ltd
Priority date: 2009-12-28
Filing date: 2009-12-28
Publication date: 2011-07-14
Anticipated expiration: 2029-12-28
Also published as: JP5315230B2

Abstract

<P>PROBLEM TO BE SOLVED: To shorten starting time and stopping time while improving efficiency on starting and stopping in a seal device of a rotating machine using an abradable member. <P>SOLUTION: The device consists of a ring member 10 held in a casing 2 so as to be situated in the outer periphery of a turbine rotor 1, a seal fin 6 mounted in either the ring member 10 or a part opposed to the ring member 10 in the turbine rotor 1, and an abradable member 4 mounted in a part opposed to the seal fin 6 in either the ring member 10 or turbine rotor 1, and holds the ring member 10 in the casing 2 so as to be movable in the direction of a rotor shaft. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

本発明は蒸気タービン又はガスタービン等の回転機械のシール装置に関する。 The present invention relates to a sealing device for a rotary machine such as a steam turbine or a gas turbine.

蒸気タービン又はガスタービン等の回転機械において、静止部と回転部（タービンロータ）の間隙を通る作動流体（蒸気やガス等）の漏れを防止するシール装置としては、その静止部及び回転部にシールリング及びシールフィンを取り付けたものがある。シール装置におけるシール間隙（シールリングとシールフィンの間隙）を小さくすると作動流体の漏えいが防止できるので、タービンの効率を向上させることができる。 In a rotary machine such as a steam turbine or a gas turbine, as a sealing device for preventing leakage of working fluid (steam, gas, etc.) passing through a gap between a stationary part and a rotating part (turbine rotor), the stationary part and the rotating part are sealed. Some are equipped with rings and seal fins. If the seal gap in the seal device (the gap between the seal ring and the seal fin) is reduced, the leakage of the working fluid can be prevented, and the efficiency of the turbine can be improved.

シール間隙を小さくする技術としては、静止部及び回転部のシール部材のうち一方に切削性の良いアブレイダブル部材を使用しつつ他方のシール部材にシールフィンを取り付けることでシールフィンでアブレイダブル部材を切削可能な構成とし、２つのシール部材の間に適正なシール間隙が形成されるようにしたものがある（特許文献１参照）。 As a technology for reducing the seal gap, a sealable fin is abradable by attaching a seal fin to the other seal member while using an abradable member having good machinability for one of the seal members of the stationary part and the rotating part. There is a configuration in which a member can be cut and an appropriate seal gap is formed between two seal members (see Patent Document 1).

特開２００２−２２８０１３号公報Japanese Patent Laid-Open No. 2002-228013

ところで、タービンの起動時及び停止時には、静止部と回転部の間にロータ軸方向の熱伸び差が生じる。これは、上記技術のようにアブレイダブル部材を使用する場合も同様で、アブレイダブル部材が切削される範囲が熱伸び差に付随してロータ軸方向に広くなるため、シール間隙がロータ軸方向に広がってしまう。 By the way, when the turbine is started and stopped, a difference in thermal expansion in the axial direction of the rotor occurs between the stationary part and the rotating part. The same applies to the case where an abradable member is used as in the above technique, and the range in which the abradable member is cut widens in the direction of the rotor axis accompanying the difference in thermal expansion, so that the seal gap is increased in the rotor shaft. It spreads in the direction.

このようにアブレイダブル部材が切削される範囲が広がることを防ぐ方法としては、起動時及び停止時に静止部側のシール部材をロータ径方向の外側に一時的に移動することで、アブレイダブル部材の切削を抑制するものがある。しかし、この方法では起動時及び停止時の作動流体の漏れが増大するので、起動時及び停止時の効率が低下するとともに起動及び停止時間も長くなってしまう。 As a method of preventing the abradable member from being cut in this way, the abradable member is temporarily moved to the outer side in the radial direction of the rotor at the time of starting and stopping. There are some which suppress cutting of a member. However, in this method, since the leakage of the working fluid at the time of starting and stopping increases, the efficiency at the time of starting and stopping decreases, and the starting and stopping time also becomes long.

本発明の目的は、アブレイダブル部材を利用した回転機械のシール装置において、起動時及び停止時の効率向上とともに起動及び停止時間の短縮化を図ることにある。 An object of the present invention is to improve the efficiency at the time of starting and stopping and to shorten the time of starting and stopping in a sealing device for a rotary machine using an abradable member.

本発明は、上記目的を達成するために、回転体と静止体の間に設置されるシール装置であって、前記回転体の外周に位置するように前記静止体に保持されたリング部材と、このリング部材又は前記回転体において前記リング部材と対向する部分のいずれか一方に取り付けられたシールフィンと、前記リング部材又は前記回転体のいずれか一方において前記シールフィンと対向する部分に設置されたアブレイダブル部材とを備え、前記リング部材は、前記回転体の軸方向に移動可能に前記静止体に保持されているものとする。 In order to achieve the above object, the present invention provides a sealing device installed between a rotating body and a stationary body, the ring member held on the stationary body so as to be positioned on the outer periphery of the rotating body, A seal fin attached to either one of the ring member or the rotating body and the portion facing the ring member, and a portion of the ring member or the rotating body facing the seal fin. An abradable member, and the ring member is held by the stationary body so as to be movable in the axial direction of the rotating body.

本発明によれば、起動時及び停止時の熱伸び差によるアブレイダブル部材の切削が抑制されるので、起動時及び停止時の効率を向上できるとともに起動及び停止時間を短縮できる。 According to the present invention, since cutting of the abradable member due to the difference in thermal expansion at the time of start and stop is suppressed, the efficiency at the time of start and stop can be improved and the start and stop time can be shortened.

本発明の第１の実施の形態であるシール装置の概略図。BRIEF DESCRIPTION OF THE DRAWINGS Schematic of the sealing device which is the 1st Embodiment of this invention. 図１に示すシール装置におけるアブレイダブル部材付近の拡大図。FIG. 2 is an enlarged view of the vicinity of an abradable member in the sealing device shown in FIG. 1. 本発明の実施の形態に係る比較例におけるアブレイダブル部材付近の拡大図。The enlarged view of the abradable member vicinity in the comparative example which concerns on embodiment of this invention. 本発明の第２の実施の形態であるシール装置の概略図。The schematic of the sealing device which is the 2nd Embodiment of this invention. 本発明の第３の実施の形態であるシール装置の概略図。The schematic of the sealing device which is the 3rd Embodiment of this invention. 本発明の第４の実施の形態であるシール装置の概略図。Schematic of the sealing device which is the 4th Embodiment of this invention. 本発明の第５の実施の形態であるシール装置の概略図。Schematic of the sealing device which is the 5th Embodiment of this invention.

以下、本発明の実施の形態を図面を用いて説明する。 Hereinafter, embodiments of the present invention will be described with reference to the drawings.

図１は本発明の第１の実施の形態であるシール装置の概略図であり、図２は図１に示すシール装置におけるアブレイダブル部材４付近の拡大図である。本実施の形態に係るシール装置は、図１に示すように、回転体であるタービンロータ１と静止体であるケーシング２の間に設置されており、リング部材１０と、シールフィン６と、シールフィン６と対向する部分に設置されたアブレイダブル部材４を備えている。 FIG. 1 is a schematic view of a sealing device according to a first embodiment of the present invention, and FIG. 2 is an enlarged view of the vicinity of an abradable member 4 in the sealing device shown in FIG. As shown in FIG. 1, the sealing device according to the present embodiment is installed between a turbine rotor 1 that is a rotating body and a casing 2 that is a stationary body, and includes a ring member 10, seal fins 6, and a seal. The abradable member 4 is provided at a portion facing the fin 6.

リング部材１０は、タービンロータ１を外周から取り囲む環状の部材であり、ケーシング２の内周側に設けた環状溝１１内に収納されている。リング部材１０におけるタービンロータ１の軸方向（以下において「ロータ軸方向」と称することがある）に位置する２つの面には、それぞれ、ロータ軸方向に伸縮するばね体３ａ，３ｂが取り付けられており、ばね体３ａ，３ｂは、環状溝１１内においてリング部材１０を支持している。すなわち、リング部材１０は、作用する力に応じてロータ軸方向に移動可能にばね体３ａ，３ｂによって保持されている。 The ring member 10 is an annular member that surrounds the turbine rotor 1 from the outer periphery, and is accommodated in an annular groove 11 provided on the inner peripheral side of the casing 2. Spring bodies 3a and 3b that extend and contract in the rotor axial direction are attached to two surfaces of the ring member 10 that are positioned in the axial direction of the turbine rotor 1 (hereinafter sometimes referred to as "rotor axial direction"). The spring bodies 3 a and 3 b support the ring member 10 in the annular groove 11. That is, the ring member 10 is held by the spring bodies 3a and 3b so as to be movable in the rotor axial direction according to the acting force.

タービンロータ１においてリング部材１０と対向する部分には、複数列のシールフィン６が取り付けられている。本実施の形態におけるシールフィン６は、タービンロータ１に取り付けられた動翼７の先端部（より具体的には、動翼７において、タービンロータ１の径方向（以下において「ロータ径方向」と称することがある）の最も外側に位置する面）に取り付けられている。 A plurality of rows of seal fins 6 are attached to a portion of the turbine rotor 1 facing the ring member 10. The seal fin 6 in the present embodiment is a tip of a moving blade 7 attached to the turbine rotor 1 (more specifically, in the moving blade 7, the radial direction of the turbine rotor 1 (hereinafter referred to as “rotor radial direction”). It is attached to the outermost surface).

リング部材１０においてシールフィン６と対向する面（リング部材１０の内周面）には、切削性の良いアブレイダブル部材４が設置されている。アブレイダブル部材４は、図２に示すようにシールフィン６の形状に合わせて形成されている。このようにアブレイダブル部材４を設置すると、たとえタービンの運転中に何らかの要因でアブレイダブル部材４とシールフィン６が接触しても、シールフィン６によってアブレイダブル部材４が容易に切削されるので、曲がり変形に至るような発熱は生じない。そのため、アブレイダブル部材４を用いない従来のシール構造と比較して、シール間隙（アブレイダブル部材４とシールフィン６の間隙）を小さくすることができる。 An abradable member 4 with good machinability is installed on the surface of the ring member 10 facing the seal fin 6 (the inner peripheral surface of the ring member 10). The abradable member 4 is formed in accordance with the shape of the seal fin 6 as shown in FIG. When the abradable member 4 is installed in this way, even if the abradable member 4 and the seal fin 6 come into contact with each other during the operation of the turbine, the abradable member 4 is easily cut by the seal fin 6. Therefore, heat generation that causes bending deformation does not occur. Therefore, the seal gap (the gap between the abradable member 4 and the seal fin 6) can be reduced as compared with a conventional seal structure that does not use the abradable member 4.

ここで本実施の形態に係る効果の理解を容易にするための比較例について説明する。図３は、本発明の実施の形態の比較例におけるアブレイダブル部材４付近の拡大図である。なお、先の図と同じ部分には同じ符号を付して説明は省略する（後の図も同様とする）。 Here, a comparative example for facilitating understanding of the effect according to the present embodiment will be described. FIG. 3 is an enlarged view of the vicinity of the abradable member 4 in the comparative example of the embodiment of the present invention. In addition, the same code | symbol is attached | subjected to the same part as the previous figure, and description is abbreviate | omitted (the following figure is also the same).

この比較例に係るシール装置は、上記の実施の形態と異なり、ロータ軸方向への移動が不可能なリング部材を備えている。このようなリング部材にシールフィン６の形状に対応したアブレイダブル部材４を設置して、タービンを起動又は停止させると、ケーシング２とタービンロータ１の熱伸び差に付随して、アブレイダブル部材４に対してシールフィン６がロータ軸方向に相対的に移動することになるので、アブレイダブル部材４がシールフィン６に切削されてしまう。そのため、図３に示すようにシール間隙がロータ軸方向に広がり、起動時及び停止時の効率が減少してしまうという課題があった。このようにシール間隙が広がることを防ぐ方法としては、起動時及び停止時にリング部材をロータ径方向の外側に一時的に移動するものがある。しかし、この方法では起動時及び停止時のシールができず作動流体の漏れが増大するので、起動時及び停止時の効率が低下するとともに起動及び停止時間も長くなってしまう。 Unlike the above-described embodiment, the sealing device according to this comparative example includes a ring member that cannot be moved in the rotor axial direction. When the abradable member 4 corresponding to the shape of the seal fin 6 is installed on such a ring member and the turbine is started or stopped, the abradable is accompanied by the difference in thermal expansion between the casing 2 and the turbine rotor 1. Since the seal fin 6 moves relative to the member 4 in the rotor axial direction, the abradable member 4 is cut by the seal fin 6. Therefore, as shown in FIG. 3, there is a problem that the seal gap is widened in the rotor axial direction, and the efficiency at the time of starting and stopping is reduced. As a method for preventing the seal gap from widening in this way, there is a method in which the ring member is temporarily moved to the outside in the rotor radial direction at the time of starting and stopping. However, in this method, since sealing at the time of starting and stopping cannot be performed and leakage of the working fluid increases, the efficiency at the time of starting and stopping decreases, and the starting and stopping time also becomes long.

これに対して、本実施の形態に係るシール装置は、ばね体３ａ，３ｂによってロータ軸方向に移動可能に保持されたリング部材１０を備えている。このようにリング部材１０をばね体３ａ，３ｂを介して支持すると、熱伸び差に付随してシールフィン６が移動しても、そのシールフィン６から作動流体の流れの層を介してアブレイダブル部材４に力が伝達されて、シールフィン６の移動に応じてリング部材１０がアブレイダブル部材４の形状を保持した状態でロータ軸方向に移動する。そのため、タービンの起動時及び停止時の熱伸び差が発生しても、アブレイダブル部材４がロータ軸方向に切削されることが抑制されるので、起動から定常運転を経て停止に至るまで一貫してシール間隙を小さく保持することができる。したがって、本実施の形態によれば、起動時及び停止時のタービン効率を向上できるとともに、タービンの起動及び停止の完了に要する時間を短縮することができる。また、本実施の形態によれば、切削されるアブレイダブル部材４が減少し、アブレイダブル部材４の設置範囲と劣化速度を抑制できるので、イニシャルコスト及びランニングコストを削減することができる。 On the other hand, the sealing device according to the present embodiment includes a ring member 10 that is held by spring bodies 3a and 3b so as to be movable in the rotor axial direction. When the ring member 10 is supported through the spring bodies 3a and 3b as described above, even if the seal fin 6 moves accompanying the difference in thermal expansion, the abrading is performed from the seal fin 6 through the working fluid flow layer. The force is transmitted to the double member 4, and the ring member 10 moves in the axial direction of the rotor while maintaining the shape of the abradable member 4 in accordance with the movement of the seal fin 6. Therefore, even if a difference in thermal expansion occurs between the start and stop of the turbine, the abradable member 4 is prevented from being cut in the rotor axial direction, so it is consistent from start to stop after steady operation. Thus, the seal gap can be kept small. Therefore, according to the present embodiment, it is possible to improve the turbine efficiency at the time of start and stop, and to shorten the time required for completing the start and stop of the turbine. Further, according to the present embodiment, the abradable member 4 to be cut is reduced, and the installation range and the deterioration rate of the abradable member 4 can be suppressed, so that the initial cost and the running cost can be reduced.

なお、本実施の形態では、リング部材１０を２つのばね体３ａ，３ｂで支持したが、熱伸び差に応じたリング部材１０の位置制御が可能であれば、そのうちの一方のばね体を廃し、そのばね体を廃した側が自由端となるようにリング部材１０を支持しても良い。 In the present embodiment, the ring member 10 is supported by the two spring bodies 3a and 3b. However, if the position of the ring member 10 can be controlled according to the difference in thermal expansion, one of the spring bodies is eliminated. The ring member 10 may be supported so that the side from which the spring body is removed becomes a free end.

図４は本発明の第２の実施の形態であるシール装置の概略図である。この図に示すシール装置は、シールフィン６が取り付けられたリング部材１０と、アブレイダブル部材４が設置された動翼７を備える点で先の実施の形態と異なる。このようにシールフィン６とアブレイダブル部材４を設置する対象を逆転させても、熱伸び差に応じてリング部材１０を移動させることができるので、第１の実施の形態と同様の効果を発揮することができる。 FIG. 4 is a schematic view of a sealing device according to the second embodiment of the present invention. The sealing device shown in this figure differs from the previous embodiment in that it includes a ring member 10 to which seal fins 6 are attached and a moving blade 7 on which an abradable member 4 is installed. Even if the object for installing the seal fin 6 and the abradable member 4 is reversed in this way, the ring member 10 can be moved according to the difference in thermal expansion, so the same effect as the first embodiment can be obtained. It can be demonstrated.

図５は本発明の第３の実施の形態であるシール装置の概略図である。この図に示すシール装置は、第１の実施の形態に係るばね体３ａ，３ｂに代えて、形状記憶合金３１ａ，３１ｂを介してリング部材１０を保持している点に特徴がある。 FIG. 5 is a schematic view of a sealing device according to a third embodiment of the present invention. The sealing device shown in this figure is characterized in that the ring member 10 is held via shape memory alloys 31a and 31b instead of the spring bodies 3a and 3b according to the first embodiment.

形状記憶合金３１ａ，３１ｂは、加熱されると記憶された縮んだ状態に変形するもので、雰囲気温度に応じて伸縮しリング部材１０をロータ軸方向に移動させる駆動手段として作用する。形状記憶合金３１ａ，３１ｂは、リング部材１０に作用する振動等を吸収する観点から、コイルばね状に形成することが好ましい。 The shape memory alloys 31a and 31b are deformed into a memorized contracted state when heated, and act as a driving means that expands and contracts according to the ambient temperature and moves the ring member 10 in the rotor axial direction. The shape memory alloys 31a and 31b are preferably formed in a coil spring shape from the viewpoint of absorbing vibrations acting on the ring member 10 and the like.

環状溝１１内において形状記憶合金３１ａ，３１ｂが位置する部分には、形状記憶合金３１ａ，３１ｂを加熱する加熱手段として熱媒体供給管１５ａ，１５ｂが接続されている。熱媒体供給管１５ａ，１５ｂの他端は熱媒体の供給源と接続されており、その熱媒体によって形状記憶合金３１ａ，３１ｂの加熱が可能になっている。熱媒体供給管１５ａ，１５ｂ内を流通させる熱媒体としては例えばタービンロータ１の作動流体がある。すなわち、本実施の形態に係るシール装置の設置対象が蒸気タービンである場合には、作動流体である蒸気を流通させれば良い。また、熱媒体供給管１５ａ，１５ｂには、流量調節弁１６ａ，１６ｂが設置されている。流量調節弁１６ａ，１６ｂで熱媒体の流量を調節すると、形状記憶合金３１ａ，３１ｂの温度が調節でき、これらの長さを調節できるので、タービンロータ１とケーシング２の熱伸び差に応じてリング部材１０を所望の位置に移動させることができる。 Heat medium supply pipes 15a and 15b are connected to portions where the shape memory alloys 31a and 31b are located in the annular groove 11 as heating means for heating the shape memory alloys 31a and 31b. The other ends of the heat medium supply pipes 15a and 15b are connected to a heat medium supply source, and the shape memory alloys 31a and 31b can be heated by the heat medium. An example of a heat medium that circulates in the heat medium supply pipes 15a and 15b is a working fluid of the turbine rotor 1. That is, when the installation target of the seal device according to the present embodiment is a steam turbine, it is only necessary to circulate steam that is a working fluid. The heat medium supply pipes 15a and 15b are provided with flow control valves 16a and 16b. When the flow rate of the heat medium is adjusted by the flow rate adjusting valves 16a and 16b, the temperature of the shape memory alloys 31a and 31b can be adjusted and the lengths thereof can be adjusted, so that the ring can be adjusted according to the difference in thermal expansion between the turbine rotor 1 and the casing 2. The member 10 can be moved to a desired position.

上記のように構成されるシール装置において、流量調節弁１６ａ，１６ｂを適宜開閉してこれらの温度を調節して形状記憶合金３１ａ，３１ｂの長さを調節すると、タービンロータ１とケーシング２の熱伸び差に応じてリング部材１０をロータ軸方向に移動させることができる。したがって、本実施の形態によっても、起動時及び停止時のタービン効率を向上できるとともに、タービンの起動及び停止の完了に要する時間を短縮することができる。特に、本実施の形態のようにリング部材１０を移動させると、第１の実施の形態の場合と比較して、アブレイダブル部材４に作用する力を軽減することができるので、アブレイダブル部材４が切削される範囲をより小さくすることができる。 In the sealing device configured as described above, if the lengths of the shape memory alloys 31a and 31b are adjusted by appropriately opening and closing the flow rate adjusting valves 16a and 16b to adjust the temperatures thereof, the heat of the turbine rotor 1 and the casing 2 is increased. The ring member 10 can be moved in the rotor axial direction according to the difference in elongation. Therefore, according to the present embodiment, it is possible to improve the turbine efficiency at the time of starting and stopping, and to shorten the time required to complete the starting and stopping of the turbine. In particular, when the ring member 10 is moved as in the present embodiment, the force acting on the abradable member 4 can be reduced as compared with the case of the first embodiment. The range in which the member 4 is cut can be further reduced.

なお、本実施の形態では、リング部材１０を２つの形状記憶合金３１ａ，３１ｂで支持したが、熱伸び差に応じたリング部材１０の位置制御が可能であれば、そのうちの一方の形状記憶合金をばね体に代替しても良いし、ロータ軸方向の一方側が自由端となるようにリング部材１０を支持しても良い。 In this embodiment, the ring member 10 is supported by the two shape memory alloys 31a and 31b. However, if the position of the ring member 10 can be controlled according to the difference in thermal expansion, one of the shape memory alloys can be used. May be replaced with a spring body, or the ring member 10 may be supported such that one side in the rotor axial direction is a free end.

図６は本発明の第４の実施の形態であるシール装置の概略図である。この図に示すシール装置は、第３の実施の形態に係る形状記憶合金３１ａ，３１ｂに代えて、モータ３３でリング部材１０をロータ軸方向に移動している点に特徴がある。 FIG. 6 is a schematic view of a sealing device according to a fourth embodiment of the present invention. The sealing device shown in this figure is characterized in that the ring member 10 is moved in the rotor axial direction by a motor 33 instead of the shape memory alloys 31a and 31b according to the third embodiment.

この図に示すリング部材１０は、リング部材１０をロータ軸方向に付勢するばね体３ｂと、そのばね体３ｂの付勢力に対抗してリング部材１０を支持する支持部材３２によって支持されている。支持部材３２は、モータ３３（駆動装置）によって回転することでロータ軸方向に進退するねじ３４の先端部に固定されている。タービンロータ１とケーシング２の熱伸び差に応じてモータ３３を駆動させてねじ３４を進退させると、支持部材３２がロータ軸方向に移動して、リング部材１０がロータ軸方向に移動される。 The ring member 10 shown in this figure is supported by a spring body 3b that urges the ring member 10 in the rotor axial direction, and a support member 32 that supports the ring member 10 against the urging force of the spring body 3b. . The support member 32 is fixed to the tip of a screw 34 that moves forward and backward in the rotor axial direction by rotating by a motor 33 (drive device). When the motor 33 is driven according to the difference in thermal expansion between the turbine rotor 1 and the casing 2 to advance or retract the screw 34, the support member 32 moves in the rotor axial direction, and the ring member 10 moves in the rotor axial direction.

上記のように構成されるシール装置においても、モータ３３を適宜駆動して支持部材３２の位置を調節すると、タービンロータ１とケーシング２の熱伸び差に応じてリング部材１０をロータ軸方向に移動させることができる。したがって、本実施の形態によって、起動時及び停止時のタービン効率を向上できるとともに、タービンの起動及び停止の完了に要する時間を短縮することができる。特に、本実施の形態のようにモータ３３によってリング部材１０を移動させると、第３の実施の形態の場合と比較して、熱伸び差に応じて正確にリング部材１０を移動させることができる。 Also in the sealing device configured as described above, when the motor 33 is appropriately driven to adjust the position of the support member 32, the ring member 10 is moved in the rotor axial direction according to the difference in thermal expansion between the turbine rotor 1 and the casing 2. Can be made. Therefore, according to the present embodiment, it is possible to improve the turbine efficiency at the time of start and stop, and to shorten the time required for completing the start and stop of the turbine. In particular, when the ring member 10 is moved by the motor 33 as in the present embodiment, the ring member 10 can be accurately moved according to the difference in thermal expansion as compared with the case of the third embodiment. .

図７は本発明の第５の実施の形態であるシール装置の概略図である。この図に示すシール装置は、制御装置２０を用いて熱伸び差に応じて自動的にリング部材１０をロータ軸方向に移動している点に特徴がある。 FIG. 7 is a schematic view of a sealing device according to a fifth embodiment of the present invention. The sealing device shown in this figure is characterized in that the ring member 10 is automatically moved in the rotor axial direction according to the difference in thermal expansion using the control device 20.

この図に示すシール装置は、タービンロータ１とケーシング２の熱伸び差を検出する熱伸び差検出センサ８（熱伸び差検出手段）と、形状記憶合金３１ａ，３１ｂを加熱冷却する加熱冷却装置９ａ，９ｂと、熱伸び差検出センサ８の検出値に基づいて加熱冷却装置９ａ，９ｂを制御する制御装置２０を備えている。 The sealing device shown in this figure includes a thermal expansion difference detection sensor 8 (thermal expansion difference detection means) that detects the thermal expansion difference between the turbine rotor 1 and the casing 2, and a heating / cooling device 9a that heats and cools the shape memory alloys 31a and 31b. , 9b and a control device 20 for controlling the heating / cooling devices 9a, 9b based on the detection value of the thermal expansion difference detection sensor 8.

本実施の形態における熱伸び差検出センサ８は、図７に示すように環状溝１１の入口に設置されており、そこからタービンロータ１に取り付けられたシールフィン６までの距離に基づいて熱伸び差を検出している。例えば、熱伸び差がゼロのときのシールフィン６までの距離を基準とし、当該基準距離と実際の検出距離とを比較すれば熱伸び差を検出することができる。また、熱伸び差検出センサ８は、制御装置２０と接続されており、検出した熱伸び差を出力している。 The thermal expansion difference detection sensor 8 in the present embodiment is installed at the inlet of the annular groove 11 as shown in FIG. 7, and thermal expansion is based on the distance from there to the seal fin 6 attached to the turbine rotor 1. The difference is detected. For example, the difference in thermal expansion can be detected by comparing the reference distance and the actual detection distance with reference to the distance to the seal fin 6 when the difference in thermal expansion is zero. Further, the thermal expansion difference detection sensor 8 is connected to the control device 20 and outputs the detected thermal expansion difference.

加熱冷却装置９ａ，９ｂは、環状溝１１内において形状記憶合金３１ａ，３１ｂが位置する部分に設置されている。加熱冷却装置９ａ，９ｂは、制御装置２０と接続されており、制御装置２０からの制御信号に基づいて形状記憶合金３１ａ，３１ｂの加熱冷却を行っている。 The heating / cooling devices 9a and 9b are installed in the annular groove 11 where the shape memory alloys 31a and 31b are located. The heating and cooling devices 9a and 9b are connected to the control device 20 and heat and cool the shape memory alloys 31a and 31b based on a control signal from the control device 20.

上記のように構成されるシール装置において、熱伸び差検出センサ８によって熱伸び差が検出されたら、制御装置２０は、その熱伸び差をアブレイダブル部材４に対するシールフィン６の相対移動量とし、リング部材１０をロータ軸方向に移動することでその相対移動量が小さくなるように（例えば、ゼロに近づくように）加熱冷却装置９ａ，９ｂを制御する。この制御の具体例としては、熱伸び差検出センサ８の検出値（熱伸び差）ごとに相対移動量がゼロに近づくような加熱冷却装置９ａ，９ｂの目標出力をそれぞれ設定しておき、実際に検出された熱伸び差及びこれに対応する目標出力に基づいて形状記憶合金３１ａ，３１ｂを加熱又は冷却することで、相対移動量がゼロに近づくようにリング部材１０をロータ軸方向に移動する方法がある。このようにシール装置を構成すれば、タービンロータ１とケーシング２の熱伸び差に応じてリング部材１０をロータ軸方向に自動的に移動させることができる。したがって、本実施の形態においても、起動時及び停止時のタービン効率を向上できるとともに、タービンの起動及び停止の完了に要する時間を短縮することができる。 In the sealing device configured as described above, when the difference in thermal expansion is detected by the thermal expansion difference detection sensor 8, the control device 20 uses the difference in thermal expansion as the relative movement amount of the seal fin 6 with respect to the abradable member 4. The heating and cooling devices 9a and 9b are controlled so that the relative movement amount is reduced by moving the ring member 10 in the rotor axial direction (for example, approaching zero). As a specific example of this control, target outputs of the heating and cooling devices 9a and 9b are set so that the relative movement amount approaches zero for each detection value (thermal expansion difference) of the thermal expansion difference detection sensor 8, and actually The shape memory alloys 31a and 31b are heated or cooled based on the difference in thermal expansion detected in step 1 and the target output corresponding to the difference, thereby moving the ring member 10 in the axial direction of the rotor so that the relative movement amount approaches zero. There is a way. If the sealing device is configured in this way, the ring member 10 can be automatically moved in the rotor axial direction in accordance with the difference in thermal expansion between the turbine rotor 1 and the casing 2. Therefore, also in the present embodiment, it is possible to improve the turbine efficiency at the time of start and stop, and to shorten the time required for completing the start and stop of the turbine.

なお、形状記憶合金３１ａ，３１ｂの温度をさらに正確に制御することでリング部材１０の位置を正確に制御したい場合には、環状溝１１内における加熱冷却装置９ａ，９ｂの近傍又は形状記憶合金３１ａ，３１ｂ等に温度センサを設置し、当該温度センサの検出値を制御装置２０にフィードバックしながら加熱冷却装置９ａ，９ｂの出力を制御すれば良い。 When the position of the ring member 10 is to be accurately controlled by controlling the temperature of the shape memory alloys 31a and 31b more accurately, the vicinity of the heating / cooling devices 9a and 9b in the annular groove 11 or the shape memory alloy 31a. , 31b, etc., and the output of the heating / cooling devices 9a, 9b may be controlled while feeding back the detected value of the temperature sensor to the control device 20.

また、本実施の形態では、形状記憶合金３１ａ，３１ｂの加熱手段として、加熱冷却装置９ａ，９ｂを用いたが、これに代えて第３の実施の形態に係る熱媒体供給管１５ａ，１５ｂを設置し、流量調節弁１６ａ，１６ｂを制御することで形状記憶合金３１ａ，３１ｂの長さを制御するようにしても良い。 In the present embodiment, the heating and cooling devices 9a and 9b are used as the heating means for the shape memory alloys 31a and 31b. Instead, the heat medium supply pipes 15a and 15b according to the third embodiment are used. The length of the shape memory alloys 31a and 31b may be controlled by installing and controlling the flow control valves 16a and 16b.

さらに、上記各実施の形態では、動翼７の先端とケーシング２の間に設置されるシール装置を例に挙げて説明したが、この他にも、タービンロータ１のシャフトとケーシング２の間や、タービンロータ１のシャフトと静翼の間等、回転機械における回転体と静止体の間をシールするものであれば本発明の適用が可能であることは言うまでもない。 Further, in each of the above-described embodiments, the sealing device installed between the tip of the moving blade 7 and the casing 2 has been described as an example, but in addition to this, between the shaft of the turbine rotor 1 and the casing 2, Needless to say, the present invention can be applied as long as it seals between the rotating body and the stationary body in the rotating machine, such as between the shaft and the stationary blade of the turbine rotor 1.

１タービンロータ
２ケーシング
３ばね体
４アブレイダブル部材
６シールフィン
７動翼
９加熱冷却装置
１０リング部材
１５熱媒体供給管
１６流量調節弁
２０制御装置
３１形状記憶合金
３２支持部材
３３モータ（駆動装置） DESCRIPTION OF SYMBOLS 1 Turbine rotor 2 Casing 3 Spring body 4 Abradable member 6 Seal fin 7 Moving blade 9 Heating / cooling device 10 Ring member 15 Heat medium supply pipe 16 Flow control valve 20 Control device 31 Shape memory alloy 32 Support member 33 Motor (drive device) )

Claims

A sealing device installed between a rotating body and a stationary body,
A ring member held by the stationary body so as to be positioned on the outer periphery of the rotating body;
Seal fins attached to either one of the part facing the rotating member in the ring member or the part facing the ring member in the rotating member;
An abradable member installed in a part facing the seal fin in either the ring member or the rotating body,
The ring device is held by the stationary body so as to be movable in the axial direction of the rotating body.

A sealing device installed between a rotating body and a stationary body,
A ring member held by the stationary body so as to be positioned on the outer periphery of the rotating body;
Seal fins attached to either one of the part facing the rotating member in the ring member or the part facing the ring member in the rotating member;
An abradable member installed in a portion of the ring member or the rotating body facing the seal fin;
A seal device comprising drive means for moving the ring member in the axial direction of the rotating body in accordance with a difference in thermal expansion between the rotating body and the stationary body.

The sealing device according to claim 2,
As the driving means,
A shape memory alloy that expands and contracts according to the atmospheric temperature and moves the ring member in the axial direction of the rotating body;
A sealing device comprising heating means for heating the shape memory alloy.

The sealing device according to claim 2,
As the driving means,
A spring for urging the ring member in the axial direction of the rotating body;
A support member that supports the ring member against the biasing force of the spring;
And a driving device that moves the support member in the axial direction of the rotating body.

The sealing device according to claim 2,
A thermal expansion difference detection means for detecting a thermal expansion difference between the rotating body and the stationary body;
And a control device for operating the driving means so that the relative movement amount of the seal fin with respect to the abradable member is reduced based on the thermal expansion difference detected by the thermal elongation difference detection means. Sealing device.