EP1366315A1

EP1366315A1 - Steam line closing valve and steam turbine plant comprising such a steam line closing valve

Info

Publication number: EP1366315A1
Application number: EP02717976A
Authority: EP
Inventors: Detlef Haje
Original assignee: Siemens AG
Current assignee: Siemens AG
Priority date: 2001-03-08
Filing date: 2002-02-25
Publication date: 2003-12-03
Also published as: US6929447B2; US20040037700A1; CN100416144C; WO2002075184A1; JP2004529295A; CN1496459A; DE10111187C1

Abstract

The invention relates to a steam line closing valve (14) for closing a steam line (20), especially in a steam turbine plant (10) between a first partial turbine (11) and at least one second partial turbine (15) that is operated at a lower pressure than the first partial turbine (11). According to the invention, the steam line closing valve (14) is subdivided into a plurality of elements (25a, 25b, 25c, 25d) that cooperate to cover the cross-section of the steam line (20), thereby reducing the moment of inertia <i>Iy</i> of the elements (25a, 25b, 25c, 25d).

Description

description

Steam line closure valve and steam turbine system with steam line closure entil

The present invention relates to a steam line closure valve for closing a steam line, in particular in a steam turbine plant, between a first expansion section and at least a second expansion section, which is operated at a lower pressure than the first expansion section.

An expansion section is understood to mean both separate turbine sections, each with its own housing, and sections of a turbine section arranged one behind the other in a common housing, each with its own steam supply.

Such steam line shut-off valves, also referred to as intercepting flaps, are a safety device. In saturated steam turbine sets, they are provided before the steam enters the low-pressure turbines downstream of the first sub-turbine if the overspeed that occurs when the system sheds a load cannot otherwise be limited to permissible values. In the event of a load shedding, the load torque of a generator driven by the turbo set is eliminated within a short time, for example as a result of a three-pole network short circuit. In this case, the live steam fittings are closed, so that a further steam supply to the first sub-turbine is excluded. However, the steam still stored in this sub-turbine, the intermediate steam lines and any water separator or reheater that may be present continues to expand. The expansion causes an increase in the speed of the turbo set due to the lack of load torque. It is therefore necessary to prevent this expansion and the steam from entering the second and possibly further sub-turbines. A fully tight sealing is not necessary. Small leakage currents can be tolerated.

US Pat. No. 3,444,894 discloses a device for controlling the pressure or the amount of a gaseous medium. The device has a housing which defines a longitudinally extending channel, with an inlet opening and an outlet opening for the medium. Two so-called damping vanes are arranged in the housing and can be moved relative to one another in a direction perpendicular to the longitudinal axis. Furthermore, a central element is arranged between the damper blades essentially centrally in the channel. The central element is streamlined for a favorable flow and extends along the longitudinal axis in the channel. It has a round contour of appreciable thickness at its upstream end, while tapering to a point at its downstream end.

DE 36 07 736 C2 describes a butterfly valve for pipelines and the like with a pivotally mounted flap which, in the closed position, is made of a non-or only slightly elastic plastic, such as e.g. a fluoroplastic. In the sealing area, in which it has a slightly smaller clear diameter in relation to the flap in the open position, the sealing chuck is flexibly arranged against the closed position of the flap via a spring bridge and a gap between the spring bridge and the housing. Here, the spring bridge, which has slots, is firmly anchored in the sealing lining by partial or complete sheathing and the sealing lining forms a unit with the spring bridge.

DE 38 26 592 AI shows a device for actuating a quick-closing valve in a steam line, preferably a steam line of a steam turbine. On a rotary shaft of the quick-closing flap, a pinion is arranged, with which two pairs of racks are in engagement. One pair of racks is used in conjunction with hydraulic means to open the quick-closing flap, the other pair in conjunction with closing springs for quick closing. The two independent systems for opening and closing reduce the wear of the mechanics due to the absence of play and enable damping of the flap plate of the quick-closing flap when entering the closing end position by means of a corresponding hydraulic connection. In order to keep this damping independent of different operating conditions, pressure compensators are used in connection with an interception throttle, which can also be adjusted depending on the angle of rotation. A bypass line serves to relieve the pressure on the quick-closing flap when opening, which in turn can be shut off by quick-closing shut-off valves.

In the known steam line shut-off valves, a single flap is provided, which is turned to close the steam line. The pressure in the steam line is usually between 10-15 (18) bar with a diameter of 1.2 to 1.4 m. The closing time of the steam line shut-off valve should be between one and two seconds. Due to the high load caused by pressure, the diameter of the steam line and the prevailing temperatures, the

Flaps are comparatively massive. They therefore have large dimensions and a high weight. This leads to a large moment of inertia around the intended axis of rotation. To achieve the required short closing time, considerable acceleration moments must therefore be applied to the flap.

An increase in the diameter of the flaps now used can only be achieved with great difficulty in terms of design. First of all, drives must be provided that can apply the required acceleration torques. Difficulties in realizing the Flap bearing occur. An increase in the diameter would be desirable, however, since the entire cross-sections of the steam lines between the individual sub-turbines can no longer be blocked at the current outputs of steam turbine systems. The steam line shut-off valves must therefore be arranged in the feed lines to the individual second partial turbines. A separate steam line shut-off valve is then required for every second partial turbine. This leads to a high level of constructive and financial expenditure and to an increase in the space requirement.

The object of the present invention is therefore to provide a steam line closure valve which has a reduced moment of inertia with the same dimensions or larger dimensions with the same moment of inertia and thus enables the closing of a steam line with a larger cross section.

According to the invention, this object is achieved in a steam line shut-off valve of the type mentioned at the outset in that it is divided into a plurality of elements which together can cover the cross section of the steam line.

This division allows smaller elements to be used. The moment of inertia increases quadratically with the distance to the axis of rotation. By dividing it into several elements according to the invention, this distance can be significantly reduced, so that an overall significantly smaller moment of inertia results. Since the surface of each element exposed to the vapor pressure is also reduced, lower bearing forces occur. The storage of the individual elements can therefore be realized relatively easily. With the same cross-section of the steam line, the required acceleration torque is thus significantly reduced. Alternatively, a larger cross section can be closed with the same acceleration torque. A formulaic Explanation of the relationships is given in the description of the figures.

Advantageous refinements and developments of the invention emerge from the dependent claims.

The elements advantageously cover the entire cross section of the steam line. This is understood to mean that at most small, function-related or production-related columns remain. In order to completely block the steam line, the elements are adapted to the cross-sectional shape of the steam line. Alternatively, the cross section of the steam line in the area of the steam line closure valve can be adapted to the shape of the elements. It is also possible to change both the cross section of the steam line and the shape of the elements.

In an advantageous embodiment, when the steam line closure valve is opened, the entire cross section is not released at once within the short opening time. Rather, there is a gradual, increasing release. This can be achieved by means of recesses in the form of grooves or pockets in the elements, which initially open a small cross section when the steam line closure valve is opened, before the elements release the cross section as a whole. A sudden load on the second expansion section is avoided. Furthermore, an easier controllability of the entire system is achieved when the steam line closure valve is opened.

If the elements are adapted to the cross section of the steam line, at least one of the elements advantageously has a curve. The steam line is generally round due to the prevailing high pressures and temperatures in order to minimize the material loads and to distribute them evenly. By rounding at least one of the elements, an improved flow behavior is also achieved. QJ ω M t)> μ »

C_π o i o (l o π

-t σ φ μ- d Φ

Φ Cd rr

Φ

3 σ φ

PJ d tr rt

Φ Φ

H-

?

N O:

Φ d

H- d Q Φ r + d μ- φ ω φ tr

Φ

Ö3 (i i

Φ μ- rt

Φ

PJ d

Hi s:

Φ μ-

cfl

Φ d

D μ-

Φ

cfl

Hi d = tr rt

N d

Figure 1 is a schematic representation of a steam turbine plant;

FIG. 2 shows a schematic representation of a cross section through a steam line closure valve according to the prior art;

Figure 3 is a schematic representation of a replacement model of a steam line closure valve according to the invention in a first embodiment; Figure 4 is a view similar to Figure 2 in a second embodiment;

Figure 5 is a plan view of an inventive

Steam line closure valve in a third embodiment; and Figures 6 to 11 different schematic views of other

Embodiments of a steam line closure valve according to the invention similar to FIG. 3.

A steam turbine system 10 is shown schematically in FIG. Saturated steam generated by a device, not shown, is fed to a partial steam turbine 11. After exiting this saturated steam sub-turbine 11, the steam is dewatered in a dewatering device 12 and then overheated in an intermediate superheating device 13. It is then fed via a steam line 20 to two low-pressure sub-turbines 15, which are operated at low pressure than the saturated steam sub-turbine 11. At the outlet from the low-pressure turbine section 15, a condenser 16 is arranged, in which the steam is condensed and returned. The steam flows are indicated schematically by arrows. The saturated steam turbine part 11 and the low pressure turbine parts 15 drive a common shaft 18 in the direction of arrow 19. The shaft 18 in turn drives a generator 17 for generating electrical power. ω CO [V> IV) μ ^{1 1}

(l o Cπ o Cπ o cπ

^ d HI \ 3 d N3 Ω to <J ^ rt co i CQ N rt Φ tr ⁽ -3 iQ dd φ Φ cn d cπ tr Ω φ μ- d μ- Φ 1-5 Φ d li Φ μ- li Φ Φ φ

P- PJ: μ- Ω PJ Φ tr ιQ l-i d d d tr d H d o μ- d μ- φ Ω rt d CQ d Φ Ω φ <l Ω l-i Ω>

0 tr • s: μ- Ω H d IV? d φ? ö μ- tr rt 3 Φ φ IV) Φ IV)? Φ tr μ- O 1 H 1 PJ Ω Φ d Φ μ- rt α σ> μ- Cπ l-i tP) Φ 3 PJ 1 ^ tr 3 tr d l-i rt d

Φ μ- P- CQ σ Φ Φ d li " _^ φ μ- Φ d rt • tr N Φ s: d Φ φ μ- d EN Hi Q- μ- J d μ- Hi d μ- 3 μ- rt CQ d Cfl φ 0 J IV) ω H d H dd

Cfl <! rt IV) Hi φ μ- HH o rt φ rt? r ι d Φ HS d ¹ α * do Φ φ Cπ O: Φ d ιP C ιp σ d QH d PJ N PJ

H d μ- Ω H H rt rt φ φ H μ- d h d μ »Cfl co μ- d 3 μ- l-i CQ Hi tr tr d) Φ Ω rt

Ω Φ μ- D Φ H rt d = μ- Φ μ- H tr PJ tr Φ d ι-3> ιQ J μ- μ- Φ l-i d? μ- d PJ d d: μ- tr rt d H cπ Φ 3 d Ω Φ rt Cfl Φ d 03 tr d s; ι_ι- PJ: • d J-- φ tr H d rt d PJ Φ to d

Cd Φ tP ^ Hi d rt μ- μ- φ rt H CQ Hj

Φ s: tr Cfl iQ Φ Φ d φ lS rt Φ Hi li Φ Φ φ μ- J Φ φ ιθ d cπ μ- cπ α Φ P- d to - _^

3 μ- μ- d * υ μ- 3 d Φ d μ- H PJ μ- *

• -d φ rt P. • d rt PJ: Φ μ- <! Φ Φ d Jl o tr

H d CQ Cfl Φ d E H d d φ H ö μ- vp Cd: • d tr X Φ

PJ: rt 3 y. D to co N H J d Cfl tr Hi rt μ- μ-

Ω Φ φ o Φ PO ιQ P- Ω Hi φ CQ o 3 rt Φ 1 H co tr d μ- 3 s:> Φ tr = O PJ • d H d H ι-3 d Ό φ d φ Φ N) 3 d tr d 3 Hl Φ o tr Φ PJ: μ-

M d μ- 3 o μ- H Φ ιQ O H rt Ω μ- μ- tr Φ π Cd rt μ- ω rt d d rt HI Φ Φ tr rt Φ μ- M 0

P- PJ φ Cfl rt μ- rt rt d μ- d iSl rt H Φ co μ- * _* CQ • -M ω PJ iQ 3 Φ rt • Φ dds:

Φ Ω: d φ rt d co μ- PJ μ- d X d H σ Φ tv> tr 3 μ- α d tr Φ d rt d G T3 iQ σ J PJ μ-

PJ cπ PJ d Φ l-S φ P. iQ d ιQ 3 PJ Cfl μ- H 3 co d tr Φ d φ Φ μ- α Ω μ- Φ Φ d Cfl d φ d iQ • d Φ

Ω ^ d Hi μ- 3 d Φ tr to H O ιQ <Φ μ- Φ Φ Hi tr d • d Φ • d H Φ μ- μ- d Cfl N μ-

M μ- φ ^ d Φ μ- H IV ⁾ H d φ ü rt dd

Cπ vQ D PJ φ ι-3 μ- Φ ddo Cfl H μ- μ ¹ φ Hl Hi o Ω d μ- o μ- Φ d \ - ~ Ω Φ • * »Ω φ Ω" _^ h- ¹ dod _" « d Φ H μ- d Ω? T rt tr Φ d tr H- ¹ d ^* H "

LQ φ d N tr ö 1 H H rt rt HS ι

P- IV) CQ> tr Clf μ- d J Φ ι-3 μ- μ- d PJ d d Φ Φ Φ

Φ Cπ 3 d PJ iQ μ- 3 μ- Φ fl Φ EP H d d H N ι-i o rt Ω l-i Φ? R * d μ- rt <! rt P- ιQ d Φ

3 ι-S tr Hi Φ H tr φ μ- Cd HS μ-

^ PJ φ μ- Cfl <! H rt Φ d ιQ μ- H »d 3 d

H tr d φ Φ o μ- CS3 Φ> d μ- rt φ d co rt PJ Φ Φ J ιQ rt tr H 3 d μ- tr H d P- μ- CQ s: rt Hj CQ d Φ * iQ 3 rt CQ r Φ iQ PJ: d

Ό Φ s: d • d μ- Cd μ- Φ CQ HJ C / 3 φ Φ M ω φ <d φ d tr 3 μ ¹ μ- φ co CQ Φ PJ Hi

Ω <n φ CQ Φ iQ H φ N μ- j-- d • d Φ d rt Φ

M PJ Φ tr φ H CO d Φ rt -3 Φ h rt μ- rt tr "tr φ d 1 1 PJ Φ α <i H μ- μ- dd P- • d φ φ tr d rt li» μ- Φ O Φ Φ Ω dd PJ o

PJ 1 INJ J • 3 cπ ιQ ü rt tr ιQ rt 3 H tr σ, n μ- PJ d 1 Φ Φ Φ co Φ • d μ-

1 tr 1 1 d Φ d K h 1 H Hi 1 1 1 1 1 1 [

O co IV) IV)

Cπ o Cπ o Cπ o cπ

3 IO σ μ- d to IV) to CQ Cd to tr rt N Φ tr d: Cd Cd 03 α CJ. σ 3 PO J. rt Cd σ

PJ μ- d PJ d Φ Ω cπ d Ω Φ Φ CQ • d PJ J Φ d rt Φ tr φ rt φ H- Φ μ- PJ: σ. Φ μ- μ-

CQ rt Φ tr tr Ω Cfl tr Hi tr Hj Hj d μ- s: μ- Φ Φ μ- Hj d Φ s: Φ EP tr CQ Hi Φ rt Hi Φ α <ddd φ CQ μ- ιP h- ¹ α SD CQ Hj 3 O: Φ to Φ Ω μ-

Φ $, CQ Hi Φ o μ- φ μ- μ- d μ- Ω Φ tr μ- O Φ α 3 o tr μ- Φ ^ d co tr d ^ d rt Φ Ω HS HS rt CO tr rt dd tr ω J Ω μ- Φ d Φ dd Φ μ- O P- μ-

• H tr s: O: rt o 3 rt 0. rt rt o Hi? μ- Φ μ- rt H d Φ μ- co v CD Cd μ- d and others α d μ- s Hi tfl tr d τι α Φ d rt Φ Φ μ- d Φ ιP H dd Ω H- ¹ ddd σ Φ μ - HS μ- Hi PJ d P- μ- μ-> d Φ Cfl CQ Φ PJ rt Hj φ iQ H μ- d rt rt d H- ¹ iQ Φ ιQ φ dd H- ¹ ^ d tr tc tr tc tV) d <! Ω dd Hj 3 03 • Φ

Φ rt rt d φ α φ HS d CQ α rt φ SD: Φ φ Cπ o φ tr Hi μ- J ^ O φ rt d ω α tr Φ d Hi d HS Cfl d CQ c μ- H rt tr PJ ι Hj d PJ: Φ T) d Hj O μ- α Φ ιQ P. α μ- φ CQ rt CQ CQ Hi Φ φ tr μ- d N tr d rt Φ Φ

<i φ Φ μ- P- α μ- IV) PJ Cπ Ω tr O μ- ^ P rt rt PJ: H- ¹ CQ PJ rt EP s: Φ d μ- HS

Φ HS 3 Φ PJ φ <£> 3 tr 3 3 J ιQ φ φ ιP ι IV) rt H- ¹ rt Φ φ Hj <i PO Ω σ

H N Hj α 3 Cfl • d P- d μ- P? CQ d rt φ π PJ rt Hj μ- O 0 αi tr IO μ- r σ <PJ • d Φ! Hi J d d rt Φ rt d P. rt σ H Φ α Φ σ. d Hi PJ d o

Φ φ PJ Φ Cd Hi Φ li μ- ιQ α μ- J Hj φ α Hj • rt d φ d cd JO υ - _^ μ- Φ

Cfl μ- 3 H cd Hj φ iQ Ω Φ μ- rt h- ¹ Hj μ- μ- d to Hi H- ¹ Ω Φ d Hj to rt • d α φ μ- Φ H- ¹ rt μ- Φ tr d μ- Φ Cfl rt PJ Φ φ IV ⁾ d Cd Φ tr co PO μ- Cfl

Φ φ H, H 3 Φ μ- φ μ- rt to rt Φ d-- d 03 tr Cπ ιP 3 ö 3 PO Φ Cπ Φ Ω

H d Φ φ rt 3 φ d rt M co tr d co H α φ Ω μ- J Φ φ σ. N tr

Hj Φ iQ Φ μ- υa rt 3 3 d tr s: * tr d tr N rt Φ tr dd Φ Hl d Φ d = υD Φ d Φ ι-3 μ- Φ rt ddd φ ^ Q H- ¹ tr d φ Hj • 03 μ- Ω IV) Φ • d φ rt Φ d μ- μ-

P- Φ rt d Φ to ιQ rt d H- ¹ Φ μ- ι μ- H- ¹ φ rt ^ J IV) 3 Sd Hi d Φ s; μ- PO PJ rt ι μ- μ- dd Φ IV) rt H d PJ rt φ σ μ- Φ Φ Cπ SD: d rt μ- μ- Cπ Hi rt Φ

Φ μ- d P. IV) φ IV) tfl o Φ tr Φ CQ Φ Cfl PJ D- EP d φ Φ IV) Hj to Ω υa d rt ιQ Φ cπ tr o IV) μ- d α ^ d Φ d Hj "d tr d μ- cπ? rd rt _^ Φ

SO d H tr 3 cπ Ω <! μ- o σ d μ-. iQ <! Ti d rt IV) PJ Φ rt CQ φ s:

Φ Hj PJ d tr tr O 3 φ HS σ P iQ Φ. φ o μ- dd Cπ d H PO rt Hj Φ U iQ tr H- ¹ Cd d φ * _* Ω 3 φ Φ σ Φ rt d iQ LQ d PJ μ- co Cπ Φ μ- φ μ- H- ¹ H IV ) ιQ Hi N tr ιQ II Φ dd μ- Hj Hj d Φ ι IV) d = Φ μ- α H σ rt -> d 3 φ cπ Φ P- IV) d CO H "φ <i Hj SD N Φ μ - φ Hj d cπ tr tr d H- ¹ PJ Φ tr Φ tu: 3 Ω d H cπ 3 rt μ- to o IV) φ dd co φ μ- tv> IV) tr Φ Φ α Φ rt 3 Hj

PJ d tr φ Φ Ω PJ: Φ J d tc Hj φ Φ H- ¹ tr d cπ IV) o cπ HS μ- • O Φ

Hi H- ¹ d N IV) tr SO d EP 3 H PJ = 3 <l to Φ Φ Φ 00 tr O σ d HI

? μ »μ- rt d UD rt N PJ P- to rt a ^ μ- 5! φ 3 d 3 s: d Φ ffi T) Φ si H

Cπ> φ Ω Φ φ dd μ- rt Φ dd Hi rt Φ Hj <Φ • Φ <! d to N φ J μ- Φ PJ = Φ d μ- tr H ≤ 3 α t Φ rt rt rt H CQ Φ d <Q Hj Φ α μ- μ- tr • _^ μ- tr μ- co rt H- ¹ IV) CQ μ- Φ> σ φ N φ Φ rt Φ Hj rt H φ Hj d Φ Φ ι h rt Hi

PJ Hi cπ rt Φ HS ^ α <1 H μ- dd H tr tr Φ d 3 Φ co N tr H- ¹ PO Φ Φ φ dd = d HJ HS Φ φ d Ω rt P- rt Φ SD: φ d φ dd LQ σ. Hj ddd tr

Φ ιP Φ _^ Φ σ Φ Φ H Hi dro Hj φ • φ d tv> P- μ- tr Hj N d Φ tr Φ and others Hj

H to μ- HS μ- d μ- co iQ φ Φ CQ Hj • _^ rt cπ μ- d SD φ d iQ rt> Hj d

PJ ua PO Hi Ω ^ _* ιQ Cd Ω Φ Hi Cd d PJ Φ to d <Hj to Hj φ d μ- O d σ 3 Φ cπ φ tr Φ H- ¹ tr μ- α Hi Hi Sd Cfl α d μ- "CQ SD H- ¹ φ ≤ μ- H to> do and others

SU ιP tr μ- rt tr tr Φ to Φ PJ μ- μ- to φ 3 φ Hj Φ Φ H) vp d CQ

3 PJ Φ Ω d μ- Φ 3 o rt Φ 1 ^ d α μ- Ω Ω tv> 3 Φ tr d μ- tr O Φ rt μ- tr

Ό d tr tr d H- ¹ d φ Cfl H PJ μ- CQ tr <l Cπ d <! φ • d CQ Φ Hj to Hj μ- Cfl Φ

HI co Φ tv> Φ ιQ d tfl CQ Cfl d rt Φ rt o tr O to PJ Φ α rt μ- ιQ rt μ- rt rt d cπ d CQ Φ rt φ Φ rt Ω μ- CQ d _^ d> H CO co O Φ J Φ d tn d Φ Ω • Φ rt Φ Φ dn Hi tr to Φ α SD CQ d tr Φ CQ PO ^ Hj tr Hj co •

HS μ- tr ω • Φ φ rt H tr Cd IV) Hi rt PJ Hj d cπ SD rt Ω μ- tr ιQ d Φ ω IV) ιO Ω d • Φ s: CQ H Cπ d = Hj ddd Ω μ- d IV) CO tr Φ μ- Φ d DO d μ- ιθ Cπ α d? Φ d μ- Φ Ω tr μ- d vQ Ω d CD Φ H d d P- Cπ Φ Ω d tr μ- Φ Φ <d Hi H <J μ- H φ Φ a IV) tr υa SD Hl 3 Φ

Φ α tr Φ Φ H d o rt J o rt d tr d PJ P -0 • d: PJ d CQ Φ HS 1 • Hi 1 Hj Φ IV) d Φ 0- d cπ tr υa Hj 1 P-

PJ tr O α rt Φ 1 ιQ PJ 1 Cπ ιQ IV) d Φ P- Φ Φ d Φ 1 Φ s: μ- Φ CQ d tr α Cfl σ> Cfl 1 Hj

1 1 HS SU 1 d 1 1 I

co co O PO

Cπ o Cπ σ cπ O Cπ tr

Φ μ-

CSS

* d μ-

Φ

3 μ-

N s:

Φ μ-

CD

H φ

3 φ d rt

Φ d

PO cπ

* P _* J

PO

Cπ tr

•

In the embodiments shown in FIGS. 3, 10 and 11, the elements 25a, 25b, 25c, 25d and 25a, 25b used have the same moment of inertia J _y around them

Axis of rotation y. The width of the individual elements 25a, 25b, 25c is selected such that the elements 25a, 25b, 25c have the same moment of inertia J _y about their axis of rotation y. The middle element 25b therefore has a smaller width.

By using elements 25a, 25b, 25c, 25d with the same moment of inertia J _y , the same drive 26a, 26b, 26c, 26d can be used for each of the elements 25a, 25b, 25c, 25d. When several or all of the elements 25a, 25b, 25c, 25d are driven together, the gear mechanism 27 is loaded evenly and therefore has a longer service life.

The physical relationships are explained in more detail below. The bases used for the calculation can be found, for example, in W. Beitz, K.-H. Küttner (editor), "Dubbel-Taschenbuch für den Maschinenbau", Springer Verlag, 16th edition, 1987, page B 32.

In the prior art, the steam line 20 is closed by rotating the flap 21, which covers the entire cross section of the steam line 20. The rotational acceleration φ for closing depends on the applied acceleration torque M _y and the moment of inertia l _y by

Axis of rotation y.

The thickness of the flap 21 is significantly smaller than its radius and can therefore be neglected when calculating the moment of inertia J _y . The moment of inertia I _yιK i _{Ppe of} a flap 21 results in: 17 y, flap = -. * rr ²

with: m: mass of the flap r: radius of the flap

5

The moment of inertia I _{y mder of} a cuboid element 25, also neglecting the thickness, results in:

l T y, cuboid = - .. _ * h ²

10 with: m: mass of the cuboid b: width of the cuboid The mass of flap 20 and element 25 can be regarded as identical, since in both cases the same cross section of the steam line 20 is to be closed.

15

Dividing the individual element 25 into a number of n identical elements 25a, 25b, 25c, 25d results in:

2 ^Z 0 ^U 1 T y, per cuboid - ~ ΞL * n KLYr I / Un) - - * ^ ~

1/5 n

1 y, cuboid ~ ⁿ ... \ ^ IU) -

12 3 n

When using 4 elements 25a, 25b, 25c, 25d, i.e. n = 4:

OK r ™ * * r ²

^ - - ¹ 1 y, each cuboid

3 16 m

1 ry, cuboid = 4 ^ * 1r y, each cuboid = - .. — _ - * r _v ²

If you compare the moments of inertia I _yιK ι _appe , I _{y, cuboid of} a single flap 21 and four elements 25a, 25b, 25c, 25d, then 30 results in:

Iyßuader _, W * ₂ ^m * 2 \ _ j_

Iy, flap 12 4 3 In general:

ly, cuboid _ * »«. r _\ ^M * 2 \ * i Iy, flap 3 ft 4 3 tl

5

By dividing the single flap 21 into four similar elements 25a, 25b, 25c, 25d, the moment of inertia I _y can thus be reduced to a third. If a constant rotational acceleration φ is to be maintained, the acceleration torque M _y can therefore also be reduced to one third

be reduced. Even with a slight increase in

Mass by using several elements 25a, 25b, 25c,

25d there is still a substantial reduction in the moment of inertia I _y .

This image is not changed significantly even taking into account a significant thickness d of the elements 25a, 25b, 25c, 25d. If we take the thickness d dex elements with half the width b as an example, we get:

Iy, cuboid = ^ (b '+ d ² ) = ^ Hb ² +) = / ⁵ _4S (m * b ² )

25 Using n identical elements 25a, 25b, 25c, 25d results in

Iy _{e Q} uader = ^ gm * (2r / uf = ^ TH *

For n = 4 we get: T - 5 / m * v ²

1 y, cuboid ~ / Λ Q '"r« 0.42

In general:

Iy.Quader ₌ rf / _m *! ) / (! *, *) = 5 / * l_ ly, flap ⁿ

Even taking into account the thickness d of the elements 25a, 25b, 25c, 25d, the moment of inertia J _{y can be} reduced to less than half. The acceleration torque M _y for the drive 26 can therefore be the same

Rotational acceleration φ can be significantly reduced.

Larger cross-sections can also be made without significantly increasing the acceleration torque M _y while maintaining the same

Rotational acceleration φ are closed. For the calculation, the dimensions of the elements 25a, 25b, 25c, 25d are changed so that the same acceleration torque M _y results as for a flap 21. The following then applies:

1 y, cuboid, new

1 y, cuboid, new 1 y, flap, old ^^

J. y, flap, old

Without considering the thickness d of the flaps:

I, cuboid, new _, ^m % _ ₁

1 y, flap, old 3

3 * n

vaue

If we set n = 4 again, we get: r new = 73 r old

Taking into account the thickness d of the elements 25a, 25b, 25c, 25d, the following results:

If we set n = 4 again, we get:

The radius of the steam line 20 to be closed can thus be increased by 73% or 55% without an increase in the acceleration torque M _{y being} necessary in order to maintain the desired rotational acceleration φ. This corresponds to an increase in the cross-sectional area of the steam line 20 by a factor of 3 or 2.4.

Overall, the subject of the present invention results in a steam line closure valve 14 with a reduced moment of inertia I _y . If the dimensions of a steam line 20 to be closed remain the same, the required acceleration torque M _y can therefore be significantly reduced. Alternatively, larger cross sections can be closed with the same acceleration torque.

Claims

claims

1. Steam line closure valve for closing a steam line (20), in particular in a steam turbine plant (10) between a first expansion section (11) and at least a second expansion section (15), which is operated at a lower pressure than the first expansion section (11), characterized by several Elements (25a, 25b, 25c, 25d), which together can cover the cross section of the steam line (20).

2. Steam line closure valve according to claim 1, characterized in that at least one of the elements (25b; 25c) is provided with one or more recesses (29) which do not extend over the entire thickness (d) of the elements (25a, 25b, 25c , 25d) extend.

3. Steam line shut-off valve according to claim 2, so that the recesses (29) deepen towards the edge of the element (25b; 25c).

4. Steam line closure valve according to one of claims 1 to 3, characterized in that the elements (25a, 25b, 25c, 25d) to the cross section of the steam line (20) or the cross section of the steam line (20) to the elements (25a, 25b, 25c , 25d) are adapted or both the cross section of the steam line (20) and the elements (25a, 25b, 25c, 25d) are changed.

5. steam line closure valve according to claim 4, d a d u r c h g e k e n n z e i c h n e t that at least one of the elements (25a; 25d) has a curve (28).

6. steam line closure valve according to one of claims 1 to 5, characterized in that the elements (25a, 25b, 25c, 25d) have the same width (b).

7. steam line closure valve according to one of claims 1 to 5, d a d u r c h g e k e n z e i c h n e t that the elements (25 a, 25 b, 25 c, 25 d) have different dimensions to adapt to the cross section of the steam line (20).

8. steam line closure valve according to one of claims 1 to 7, characterized in that the elements (25a, 25b, 25c, 25d) have the same moment of inertia ij _y ) about an axis of rotation (y).

9. steam line closure valve according to one of claims 1 to 8, d a d u r c h g e k e n z e i c h n e t that the elements (25a, 25b, 25c, 25d) of the steam line closure valve (14) are independently movable.

10. Steam line closure valve according to one of claims 1 to 8, so that several elements (25a, 25b; 25c, 25d) of the steam line closure valve (14) are connected via a gear (27a; 27b) to a common drive (26a; 26b).

11. Steam turbine system with at least one first expansion section (11) and at least one second expansion section (15), which is operated at a lower pressure than the at least one first expansion section (11), and with at least one steam line (20) for feeding the second expansion section ( 15), characterized in that in each of the steam lines (20) upstream of feeds (20a, 20b) to the second expansion section (15) a steam line shutoff valve (14) is arranged.