PH12015000064B1

PH12015000064B1 - Sealing apparatus with brush

Info

Publication number: PH12015000064B1
Application number: PH12015000064A
Authority: PH
Inventors: Sam Sub Byun; Beang Kee Ha; Jae Hwa Son
Original assignee: Turbopowertech Co Ltd
Priority date: 2014-04-08
Filing date: 2015-03-06
Publication date: 2016-09-26
Also published as: PH12015000064A1; KR101442739B1

Abstract

Disclosed herein is a sealing apparatus with a brush that effectively seals a space between a rotor portion and a casing, minimizes the vibration of a turbine, and improves electricity generating and durability of the rotor portion. The sealing apparatus with the brush, including: a sealing portion provided for a casing of a turbine to seal a flow of a fluid leaking between the casing and a rotating body rotated in the casing; a brush portion that is provided for the sealing portion and includes a plurality of bristles disposed to surround an outer circumference of the rotating body; a shock preventing portion disposed to be spaced in a predetermined interval from a front side of the brush portion so as to block a flow of the fluid flowing along the outer circumference of the rotating body; and a bristle plate that is provided to support a rear side of the brush portion and has a plurality of guide holes formed therethrough to be inclined upward toward the casing as it goes from an inflow direction to an outflow direction of the fluid.

Description

non a,

SEALING APPARATUS WITH BRUSH ~~ : “2, 2 A

AN foi , 7 fi

BACKGROUND OF THE INVENTION Field of the Invention :

The present invention relates to a sealing apparatus with a brush, and more fi specifically, to a sealing apparatus with a brush to effectively seal a space between a rotor portion and a casing and minimize vibration of a turbine, thereby improving electricity generating efficiency and durability of the rotor portion. :

Background of the Related Art ) Generally, turbines refer to machines that convert energy of a fluid, such as water, gas, or steam, etc. into useful mechanical work. That is, the turbines are turbo-type machines that rotate a rotating body provided with a plurality of blades in a circumferential direction at a high speed with discharge pressure of steam or gas.

Recently, with the industrialization and development of technologies, the turbines such as steam turbines and gas turbines have a tendency to become larger and to be operated at higher temperatures and pressures.

In the turbines, since steam leakage occurring at a sealing portion between the rotating body and a stationary casing of the turbines causes efficiency of the turbines to be lowered and becomes a main reason that increases fuel costs, a design technology of the sealing apparatus to reduce the steam leakage is very important.

Here, the sealing apparatus made of stainless steel used for high temperature and high pressure turbines, such as the steam or gas turbines, plays an important role in

. . ' , * > ! preventing the steam or gas leakage to increase energy producing efficiency of a ~ - generator and inhibiting vibration of the rotating body due to a fluid. :

FIG. 1 is a cross sectional view illustrating a state in that labyrinth type sealing = apparatuses in the related art are mounted to the turbine, and FIG. 2 is a cross sectional ~ view illustrating the labyrinth type sealing apparatuses in the related art. :

As shown in FIGS. 1 and 2, the labyrinth type sealing apparatuses S in the related = art are, respectively installed on outer rings and inner rings of diaphragms 3 mounted on a o casing. ©

Here, the labyrinth type sealing apparatuses 5 are widely used as contactless type annular sealing apparatuses of the turbines and reduces an amount of leak by inducing a throttling process in a fluid flowing into the turbines with sharp teeth 6. That is, the amount of leak of the fluid is reduced due to an effect of pressure drop occurring while the fluid is repeatedly throttled and expanded in a state in which the teeth 6 are arranged in turn in a flow direction of the fluid.

Notwithstanding, when a space is sealed using the labyrinth type sealing apparatuses 5, an efficiency loss caused by the leak of the fluid through gaps between the rotor portion 1 and the teeth 6 accounts for 33% or more of the total efficiency loss of the turbines.

In order to solve the problem described above, a fluid leakage loss can be reduced by narrowing the gaps between the teeth 6 and the rotor portion 1. However, there is a problem that the sealing effect is significantly reduced over time, as the teeth 6 being intermittently into contact with the rotor portion I due to vibration or thermal deformation of the rotor portion 1, and thereby the teeth 6 are rapidly worn.

Further, the narrower the gaps between the teeth 6 and the rotor portion 1 are, the more rotational vibration of the rotor portion 1 is increased. Thus, the gaps should be maintained to be equal to or greater than a predetermined distance. Therefore, the ~ amount of leak of the fluid is increased. | <

FIG. 3 is a cross-sectional view illustrating a sealing apparatus with a brush in the = related art. _

As shown in FIG. 3, the sealing apparatus with the brush includes a brush portion - 7 sealing the gap between the rotor portion 1 that is a rotating body and the stationary * casing 3, and bristle plates 9 and 8 supporting front and rear sides of the brush portion 7. ~

Here, the brush portion 7 is provided with a plurality of the bristles in a closely- a set form. The brush portion 7 reduces a flow of the leaking fluid by forming a high pressure region and a low pressure region divided from each other. oo In this case, in the sealing apparatus with the brush, since the brush portion 7 directly comes into contact with the rotor portion 1 to seal the fluid, the fluid leak can be reduced compared to that of the labyrinth type sealing apparatus. Further, as each of the bristles is flexibly bent and supports an outer circumference of the rotor portion 1, an amount of loss of rotational movement is reduced.

However, in the related art, since the fluid passed through the brush portion 7 can only flow into gaps between the rear bristle plate 8 and the rotor portion 1, the flow is concentrated on a side of a free end of the brush portion 7.

Accordingly, the fluid passing through the side of the free end of the brush portion 7 is compressed and highly pressurized by continuously incoming fluid, thereby applying an excessive pressure on the side of free end of the brush portion 7.

That is, the high pressure fluid concentrated and compressed on the side of the free end of the brush portion 7 reduces durability by inducing vibration of the rotor portion 1, and generates plastic deformation, such as bending or diverging, of the bristles at the side of the free end of the brush portion 7.

; | Co, .

Accordingly, reduction of the durability, such as reduction of elasticity and ~ rigidity, etc. occurs prematurely and a sealing performance does not constantly z ho maintained because of reduction of coherency to the rotor portion 1. =

In addition, a fluid sealing performance-is reduced, because the brush portion 7 ; exposed out of a lower portion of the front bristle plate 9 is easily worn in a deteriorated ~ state by foreign substances flowing along with the fluid flowing from the high pressure “ region to the low pressure region at a high speed. -

The fluid flowing into the lower portion of the front bristle plate 9 is stagnated at ol the brush portion 7 and compressed by a continuously inflowing of subsequent fluid.

Due to this, there is a serious problem that vibration and, at the same time, mechanical damages to the rotor portion 1 being pressed are induced.

SUMMARY OF THE INVENTION )

The present invention is directed to provide a hybrid sealing apparatus for a turbine which has improved electricity genetating efficiency and durability of a rotor portion by effectively sealing a space between the rotor portion and a casing and minimizing vibration of the turbine.

One aspect of the present invention to achieve the above object provides a sealing apparatus with a brush, including: a sealing portion provided for a casing of a turbine to seal a flow of a fluid leaking between the casing and a rotating body rotated in the casing; a brush portion that is provided for the sealing portion and includes a plurality of bristles disposed to surround an outer circumference of the rotating body; a shock preventing portion disposed to be spaced at a predetermined interval in front of the brush portion so as to block a flow of the fluid flowing along the outer circumference of the rotating body; and a bristle plate that is provided to support a rear side of the brush portion and has a

' i ’ 5 ' plurality of guide holes formed therethrough to be inclined upward toward the casing as it =o goes from an inflow direction to an outflow direction of the fluid. z

Prot

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects, features and advantages of the present invention % - will become more apparent to those of ordinary skill in the art by describing in detail we exemplary embodiments thereof with reference to the accompanying drawings, in which: y

FIG. 1 is a cross sectional view illustrating a state in which labyrinth type sealing o apparatuses in the related art are mounted to the turbine;

FIG. 2 is a cross sectional view illustrating the labyrinth type sealing apparatuses in the related art;

FIG. 3 is a cross sectional view illustrating a sealing apparatus with a brush in the related art; ’

FIG. 4 is a cross sectional view illustrating a state in which sealing apparatuses with brushes according to an embodiment of the present invention are mounted to surround a rotor portion;

FIG. 5 is a perspective view illustrating the sealing apparatus with the brush according to the embodiment of the present invention;

FIG. 6 is a side cross-sectional view illustrating the sealing apparatus with the - brush according to the embodiment of the present invention;

FIG. 7 is a rear view illustrating the sealing apparatus with the brush according to the embodiment of the present invention;

FIG. 8 is a front view illustrating the sealing apparatus with the brush according to the embodiment of the present invention;

FIG. 9 is a perspective view illustrating a sealing apparatus with a brush according to another embodiment of the present invention; = ~

FIG. 10 is a rear view illustrating the sealing apparatus with the brush according < to another embodiment of the present invention; and ©

FIG. 11 is a side cross-sectional view illustrating the sealing apparatus with the ~ brush according to another embodiment of the present invention. -

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT y

Hereafter, preferred embodiments of the present invention to embody the o objectives described above are described with reference to the accompanying drawings in detail. The same names and reference numbers are used throughout the drawings to refer to the same or like parts and additional descriptions of them may be omitted.

FIG. 4 is a cross sectional view illustrating a state in which sealing apparatuses "with brushes according to an embodiment of the present invention are mounted to surround a rotor portion.

As shown in FIG. 4, the sealing apparatuses with the brushes 100 according to the embodiment of the present invention are mounted to seal a flow of a fluid f leaking between a casing 20 of a turbine and a rotating body 10.

Here, a plurality of blades 27a may be coupled on a circumference of the rotating body 10. In this case, the sealing apparatuses with the brushes 100 are disposed in a circumferential direction between an outer circumference of the rotating body 10 and an inner circumference of the casing 20 to seal the flow of the fluid f flowing between the rotating body 10 and the casing 20. Of course, it is also possible that the sealing apparatuses with the brushes 100 may be mounted between the casing 20 and ends of the blades 27a to reduce a leaking flow of the fluid.

That is, the sealing apparatuses with the brushes 100 is preferably understood as

- . oo , being mounted on any place, including the rotor portion and blades 27a, etc., in which the ~ sealing between the rotating body 10 rotated in the casing and the stationary casing 20 is - needed. | | -

As represented by arrows in FIG. 4, the fluid f, such as steam or gas, etc., which is _ introduced into the casing 20 passes through partitions 27 of diaphragms fixed to the : casing 20, and rotates the blades 27a provided for the rotor portion. The fluid f is then * subjected to a process in which the fluid rotates next blades according to a guidance of the ~ partitions 27 and discharged to outside. -

Through this process, an electricity generator receives a rotational force via the rotor portion rotated along with each of the blades 27a, and generates electricity by converting the rotational force into electrical energy.

FIG. 5 is a perspective view illustrating the sealing apparatus with the brush according to the embodiment of the present invention, FIG. 6 is a side cross-sectional view illustrating the sealing apparatus with the brush according to the embodiment of the present invention, FIG. 7 is a rear view illustrating the sealing apparatus with the brush according to the embodiment of the present invention, and FIG. 8 is a front view illustrating the sealing apparatus with the brush according to the embodiment of the present invention.

On the other hand, referring to FIGS. 5 to 8, the sealing apparatus with the brush 100 includes a sealing portion 110, a brush portion 130, a shock preventing portion 120, and a bristle plate 140.

Here, the sealing portion 110 is provided for the casing 20 to seal the flow of the fluid f leaking between the casing 20 of the turbine and the rotating body 10 rotated in the casing 20.

Specifically, the sealing portion 110 1s disposed between the outer circumference

. . _ of the rotating body 10 and the inner circumference of the casing 20, provided in a ring ~ form, and circumferentially disposed along the inner circumference of the casing 20 to < be coupled and fixed thereto. =

Here, the sealing portion 110 may be provided with labyrinth teeth 112 protruding ~ to block the flow of the fluid flowing along an outer portion of the rotating body 10. -

The labyrinth teeth 112 protrude in the circumferential direction on a surface of the w sealing portion 110 which faces the rotor portion 1, and may be disposed in a plurality of o rows to be spaced from each other. 5

A brush coupling groove 113 is provided in the sealing portion 110 between the labyrinth teeth 112. The brush portion 130, the shock preventing portion 120, and the bristle plate 140 may be coupled in the brush coupling groove 113.

In this case, the brush portion 130 may be welded in the brush coupling groove 113 to be fixed therein. Further, the brush portion 130 may be fixed by coupling the shock preventing portion 120 and the bristle plate 140 separately provided in front and rear sides of the brush portion 130. Of course, it is also possible that the shock preventing portion 120 and the bristle plate 140 are integrally formed on the sealing portion 110.

Here, a hooking groove portion may be formed in an inner portion of the brush coupling groove 113, and a hooking portion formed by bending on an upper end of the shock preventing portion 120 and the bristle plate 140 may be inserted into the hooking groove portion and fixed thereto.

A mounting portion 111 to be coupled in the inner circumference of the casing 20 may be formed on a side of the sealing portion 110. Specifically, the mounting portion 111 may be formed to be coupled into a coupling groove 21 formed along the inner circumference of the casing 20 and be inserted into an inner side of the coupling groove

- . Cy , 21, thereby being coupled and fixed thereto. ~

At this time, it is preferred that the sealing portion 110, the shock preventing - portion 120, the brush portion 130, and the bristle plate 140 be made of an iron-based = alloy or a copper-based alloy, etc., containing nickel, chrome, and cobalt, etc. which are ~ : high temperature stabilizing materials. -

For this reason, the sealing apparatus with the brush 100 may has stability against heat generated by friction with the rotating body 10 so that the sealing apparatus with : the brush does not easily deform and can maintain its structure. o

It is preferred that the sealing portion 110, the shock preventing portion 120, and the bristle plate 140 be provided in a ring form to be installed in a space between the casing 20 and the rotating body 10, and made by centrifugal molding. : Accordingly, the sealing portion 110 may be molded in an exact shape to be closely coupled to the inner circumference of the casing 20. Further, the labyrinth teeth 112 installed on the sealing portion 110 to protrude therefrom, the shock preventing portion 120 and the bristle plate 140 may be correctly molded to meet a design in which intervals between ends of them and the outer circumference of the rotating body 10 are preset.

Additionally, it is further preferred that the sealing apparatus with the brush 100 be made of a low rigidity material so as not to damage the rotating body 10 upon friction, and is provided as a replaceable component.

On the other hand, the brush portion 130 includes a plurality of bristles 130a provided along a central portion of the sealing portion 110 to surround the outer circumference of the rotating body 10. Here, it is preferred that the bristles 130a be made of a pliable material having elasticity and heat-resistance.

In the bristles 130a, ends 132 thereof may be fixed to the sealing portion 110 by

Co C0 electric beam welding (EBW) using an electric beam. In this case, the other ends 133 ~ of the bristles 130a extend toward the outer circumference of the rotating body 10. - oo

Further, it is preferred that the bristles 130a be provided to have a length that is = long enough to cause the other ends 133 to come into contact with a surface of the outer ~ circumference of the rotating body 10 to correspond to an interval between the casing 20 : and the rotating body 10. Here, the brush portion 130 is provided in a closely clustered - form of the plurality of the bristles 130a, and can reduce an amount of leak of the fluid : as pressure and velocity are reduced by passing through narrow rifts between the bristles 2 130a.

It is preferred that the shock preventing portion 120 and the bristle plate 140 be provided to have lengths that are long enough to cause ends of shock preventing portion : 120 and the bristle plate 140, respectively, to be spaced from the outer circumference of the rotating body 10. Accordingly, a flow passage enabling the fluid f to pass through the brush portion 130 is secured.

On the other hand, referring FIG. 6, the shock preventing portion 120 is disposed at a predetermined distance in front of the brush portion 130 to block the flow of the fluid f flowing along the outer circumference of the rotating body 10.

Here, it is preferred that the shock preventing portion 120 be disposed in the circumferential direction to cover a side of a front surface of the brush portion 130, in which an end 124 of the shock preventing portion is coupled to the sealing portion 110 and the other end 123 of the shock preventing portion extends toward the outer circumference of the rotating body 10. In this case, a gap through which the fluid f flows is formed between the other end 123 of the shock preventing portion 120 and the outer circumference of the rotating body 10. oo

Specifically, the shock preventing portion 120 is formed in a small thickness at a oo Cop side of the other end 123 so that a rear surface of the side of the other end 123 is spaced ~ from the front surface of the brush portion 130. The side of the end 124 of the shock < preventing portion 120 is provided to have a greater thickness so that the rear surface of 2 the side of the end 124 is closely supported on the front surface of the brush portion 130. ~

At this time, it is preferred that the front surface of the shock preventing portion - 120 be provided in a flat form, and the rear surface thereof includes a curved portion 125 = formed roundly to connect the side of the other end 123 and the side of the end 124 : which are formed to have different thicknesses. o

Specifically, the shock preventing portion 120 is disposed to be spaced from the brush portion 130 toward the inflow direction of the fluid f. At this time, the fluid f can flow toward the brush portion 130 along the gap formed between the other end 123 of the shock preventing portion and the outer circumference of the rotating body 10, after firstly coming into contact with the front surface of the shock preventing portion 120.

Accordingly, since the high pressure fluid f flowing at a high speed does not directly come into contact with the brush portion 130, wearing damages of the brush portion 130 due to the speed/pressure of the fluid f self and foreign substances in the fluid f can be minimized, thereby improving durability.

Additionally, a fluid chamber h to expand the fluid f included therein is formed between the rear surface of the shock preventing portion 120 and the front surface of the brush portion 130. Here, the fluid chamber h is formed between the rear surface of the side of the other end 123 of the shock preventing portion, which is formed in a small thickness, and the front surface of the brush portion 130. The rounded and curved portion 125 is formed on an inner surface of an upper portion. of the fluid chamber h.

Specifically, the fluid f that collides with the front surface of the shock preventing : portion 120 flows into the gap between the other end 123 of the shock preventing

LY | Cn portion 120 and the outer circumference of the rotating body 10, and pressure is lowered - as the fluid is spread and expanded while it flows toward the fluid chamber h. -

By this pressure drop, pressure applied to the brush portion 130 is reduced as the @ fluid passes through between the bristles 130a, as well as the amount of leak passing ’ through the brush portion 130 is reduced. ~

When the high pressure fluid f passes through the brush portion, the bristles 130a of the rear side are bent in the flow direction of the fluid f and elastic deformation, such > as divergence of each of the bristles 130a in left and right directions, etc. occurs. The 0 drop of pressure applied to the brush portion 130 as described above can reduce a degree of elastic deformation of each of the bristles 130a, and alleviates reduction of the elasticity/rigidity of the bristles 130a, thereby improving durability of a product.

Meanwhile, referring FIGS. 6 and 7, the bristle plate 140 supports the rear side of the brush portion 130. A plurality of guide holes 141 provided to be inclined upward toward the casing 20 as it goes from the inflow direction to the outflow direction of the fluid f.

Here, the amount of leak can be reduced by preventing the bristles 130a from being bent, which bring the end of the brush portion 130 into close contact with the rotating body 10, while the fluid f passes through the brush portion 130.

Specifically, the fluid f passes through the brush portion 130, flows into the gap between the end 142 of the bristle plate 140 and the outer circumference of the rotating body 10, and compresses a lower side of the brush portion 130.

At this time, a free end of the brush portion 130 1s bent toward the rear side in the direction of the fluid f by a pressing of the fluid f That is, the fluid f elastically deforms . the brush portion 130 while flowing from the high pressure region that is at a front side of the brush portion 130 to the low pressure region that is at the rear side of the brush oo C3 portion 130. >

Here, the plurality of guide holes 141 are formed through the bristle plate 140 : along a portion that supports the rear surface of the brush portion 130 in a up and down 2 co direction and the circumferential direction of the bristle plate 140. i.

That is, the fluid f can be guided to flow toward the guide holes 141, as well as - the gap between the end 142 of the bristle plate 140 and the outer circumference of the - rotating body 10. At this time, since the guided fluid bring the bristles into close contact o with the bristle plate 140 to prevent the brush portion 130 from being bent, the free end of - the brush portion 130 can be brought into close contact with the rotating body 10, thereby improving sealability.

Although the amount of leak of the fluid can be reduced as the gap between bristle plate 140 and the rotating body 10 becomes narrower, vibration of the rotating body 10 due to compression of the fluid is increased. At this time, the guide holes 141 of the bristle plate 140 cause the fluid to dispersedly flow to the entire brush sortion 130, so that vibration of the rotating body 10 is minimized even though the gap between the bristle plate 140 and the rotating body 10 becomes narrower.

Here, by forming the fine guide holes 141 to correspond to the narrowed gaps between the bristle plate 140 and the rotating body 10, a sealing performance can be maintained and durability of the brush portion 130 can be improved.

That is, since the pressure of the fluid f is not concentrated to the lower side of the brush portion 130, but is guided toward the guide holes 141 and dispersed to the entire brush portion 130, the deformation occurring at each of portions of the brush portion 130 is minimized, thereby improving durability.

Further, since the pressure of the fluid f applied to each portion of the brush portion 130 is reduced by the dispersion of the fluid f, the amount of fluid leaked is re reduced, thereby improving the sealing performance of the product. - ®

Since the bristles 130a are formed of the same material, flexibility is increased as”, © it is far away from a fixed upper side portion, and the free ends of the bristles 130a are = more easily bent compared to the upper side portion. ~

At this time, the fluid f guided to the upper side by the guide holes 141 of the - bristle plate 140 can reduce flexibility of the side of the free end of the bristle plate 140 - by bring the brush portion 130 into close contact with the side of the bristle plate 140. .

Accordingly, an occurrence of a clearance between the free end 133 of the brush - portion 130 and the outer circumference of the rotating body 10 due to rotation of the rotating body 10 and the pressure of the fluid f is prevented, and thereby the sealing performance of the product can be improved.

The guide holes 141 are provided to be inclined upward toward the casing 20 as it goes from the inflow direction to the outflow direction of the fluid f. Specifically, a portion of the fluid passed through the brush portion 130 flows to the end of the bristle plate 140 and then flows along the outer circumference of the rotating body 10. The remaining fluid is guided toward the casing along inner portions of the guide holes 141 to flow away from the rotating body 10.

Accordingly, a fluid region g having a low speed is formed between a fluid 2 flowing along the outer circumference of the rotating body 10 and a fluid fl guided toward the casing. At this time, the fluid region g having a low speed reduces speed and pressure of the fluid f2 flowing along the outer circumference of the rotating body 10 and the fluid f1 guided toward the casing.

The reduction of speed and pressure of the fluid f2 flowing along the outer circumference of the rotating body 10 can prevent vibration caused by a non uniform distribution of temperature by reducing generation of frictional heat between the flow 2

Lo ‘gs and the rotating body 10 rotated in an opposite direction to that of the fluid 2. | | ~

Further, rotational resistance of the rotating body 10 caused by the flow of the - fluid £2 flowing in a different direction from the rotational direction can be reduced, and = an amount of rotational loss caused by the rotational resistance and vibration of the ~ rotating body 10 can be reduced, thereby improving the electricity generating efficiency : of the turbine. -

Further, it is preferred that the end of the bristle plate 140 be provided to have a © rounded shape. Specifically, the fluid flowing into the inner portion of the brush portion 130 is pressed by the fluid continuously introduced from the rear side, which applies high pressure to the bristles 130a disposed at the rear side of the brush portion 130.

The rear side bristles 130a are adaptively bent rearward in the flow direction of the fluid f passing through the inner portion thereof, and bent in a left and right direction along the rotational direction by friction with the rotating body 10. At this time, the fluid guided by the guide holes 141 brings the bristles 130a into close contact with the bristle plate 140. Further, since the end of the bristle plate 140 that comes into contact with the rear side bristles 130a is provided to have a rounded shape, wear loss of the rear side bristles 130a is minimized, thereby improving the durability of the product.

Further, the reduction of the sealing performance caused by deterioration of the bristles 130a is prevented and a stable sealing performance is provided, thereby improving reliability of the product.

In addition, it is preferred that a first fluid flowing interval j between the end of the bristle plate 140 and the outer circumference of the rotating body 10 be provided to be narrower than a second fluid flowing interval i between the end of the shock preventing portion 120 and the outer circumference of the rotating body 10.

Specifically, the fluid f flows through the second fluid flowing interval i, the

BE 6 brush portion 130, and the first fluid flowing interval J in turn. At this time, a great ~ quantity of fluid f introduced into the wide second fluid flowing interval i can be ~ dispersed upward and downward after stagnation in the inner portion of the fluid chamber ~ h, due to the narrowly formed first fluid flowing interval j. ~

Accordingly, since guiding of the fluid f through the guide holes 141 in an - upward direction can be smoothly accomplished, a dispersed flow of the fluid in - promoted, thereby improving the sealing performance and the durability of the product.

Further, pressure drop efficiency can be further improved by throttling protrusions 122 & and throttling groove portions 121 of the shock preventing portion 120.

Further, it is preferred that a upper end of the bristle plate 140 be provided with a protruding coupling portion 143 protruding rearward, and the protruding coupling portion 143 is fittingly coupled into the inner side of the sealing portion 110. Accordingly, the bristle plate 140 can be more securely coupled into the sealing portion 110.

Meanwhile, referring FIGS. 6 to 8, it is preferred that the shock preventing portion 120 include a plurality of the throttling protrusions 122 protruding rearward to cause the fluid f flowing upward along a rear surface facing the brush portion 130 to be throttled, and the throttling groove portions 121 connecting the respective throttling protrusions 122.

Specifically, the shock preventing portion may be provided with the throttling protrusions 122 and the throttling groove portions 121 along a lower side of a curved portion 125 connecting an end 124 and the other end 123 which are formed to have different thicknesses from each other.

That is, the throttling protrusions 122 may be formed on the rear surface of the shock preventing portion 120 in the circumferential direction, in which the throttling protrusions 122 may be formed as multiple steps in the up and down direction of the

Lo Cw oo shock preventing portion 120. At this time, 1t is preferred that rear end surface of the ~ throttling protrusions 122 be provided in a flat form. <

The throttling groove portions 121 are provided to connect the throttling = protrusions 122 disposed in the up and down direction and may be formed by sinking the ~ shock preventing portion 120 in the front side direction. At this time, it is preferred that - throttling groove portions. 121 be provided in multiple steps so as to connect the throttling + protrusions 122 disposed in multiple steps. Specifically, the fluid f inflowing between © the end of the shock preventing portion 120 and the outer circumference of the rotating - body 10 is expanded in the fluid chamber h and is guided upward along the rear surface of the shock preventing portion 120 by the guide holes 141.

Co At this time, when the rising fluid f passes through the gaps between the ends of the throttling protrusions 122 and the brush portion 130, the fluid is accelerated at a portion in front of the throttling protrusions 122, which becomes narrower, and the fluid is decelerated at the throttling groove portions 121 behind the throttling protrusions 122, which becomes wider.

That is, the accelerated fluid reduces the pressure of the fluid flowing upward by generating vortexes in an expanding process at the throttling groove portions 121. The acceleration and the deceleration of the fluid described above are referred to as a throttling process, the rising fluid is subjected to repetitive throttling actions through the throttling protrusions 122 and the throttling groove portions 121 disposed in multiple steps, and thereby has a low pressure. As described above, the amount of the fluid leak passing through the brush portion 130 can be reduced by the pressure drop of the fluid f, and thereby the sealing performance of the product can be improved.

At this time, it is preferred that a shape of an inner surface in which the throttling groove portions 121 are sunk be roundly provided. Accordingly, large spaces in which

Lo | Cog the fluid can be expanded are formed on the inner side of the throttling groove portions ~ 121, and the pressure can be more reduced, because a degree of the expansion of the fluid - that is contracted at the ends of the throttling protrusions 122 and the front surface of the 2 brush portion 130 is increased. It is preferred that a fluid inlet 141a of the guide hole ~ +5 141, which is formed at a upper most side of the bristle plate 140, be disposed higher than - the height at which the throttling protrusions 122 formed at an uppermost side of the - shock preventing portion 120. At this time, fluid outlets 141b of the guide holes 141 N may be disposed above the fluid inlets 141a. on

Specifically, the fluid f may dispersedly flow into the guide holes 141 disposed in multiple steps in the up and down direction of the bristle plate 140. That is, the fluid fis divided into various branches, some branches of the fluid pass through the lower portion of the brush portion 130, and the remaining branches are raised along the rear surface of the shock preventing portion 120.

Some of the remaining branches pass through a central portion of the brush portion 130, and the remaining branches are raised along the rear surface of the shock preventing portion 120.

That is, the fluid f rising upward along the rear surface of the shock preventing portion 120 while being guided by the guide holes 141 flows to the upper most side of the throttling protrusions 122 disposed in multiple steps, and may be throttled multiple times.

Accordingly, the pressure drop of the fluid is smoothly achieved, thereby improving the sealing performance of the product.

Of course, in this embodiment, although an example in which diameters of the guide holes 141 are the same has been described, the guide holes 141 may be formed to : have greater diameters as it goes to the upper side of the bristle plate 140.

Accordingly, the amount of the fluid f rising along the rear surface of the shock

Lo C19 preventing portion 120 may be increased, and the sealing performance of the products : may be further improved by reducing the amount of the fluid passing through the side of < the free end of the brush portion 130. ©

FIG. 9 is a perspective view illustrating a sealing apparatus with the brush - according to another embodiment of the present invention, and FIG. 10 is a rear view got illustrating the sealing apparatus with the brush according to another embodiment of the present invention. y

In this embodiment, since the description of a basic configuration except a - passing through direction of guide holes 241 is the same as in the embodiment described above, description of the same portions will be omitted.

As shown in FIGS. 9 and 10, it is preferred that the guide holes 241 be provided to be inclined in a direction opposite to the rotational direction of the rotating body 10 as it goes from the inflow direction to the outflow direction of the fluid.

That is, fluid outlets 241b of the guide holes 241 are disposed above the fluid inlets 241a, and are disposed to be spaced from the fluid inlets 241a in a direction opposite to the rotational direction of the rotating body.

The fluid passed through the brush portion 130 vibrates by a uniform flow, and a swirl phenomenon in which the fluid rotates in the rotational direction of the rotating body 10 occurs. At this time, when the amount of the fluid that vibrates is increased, a resonance phenomenon may occur by an overlap of vibrations of the fluid.

Here, fluid f3 flowing to an end of a bristle plate 240 along the outer circumference of the rotating body 10 is guided to flow in the rotational direction of the rotating body 10.

At this time, the guide holes 241 can cancel out the fluid flows flowing in opposite directions to each other by guiding fluid f4 flowing into inner sides of the guide

- | oo 20 , . holes 241 in a different direction from the fluid {3 flowing toward the end of the bristle o plate 240. =

Pt

Accordingly, the fluid flow may be rectified in an axial direction to prevent the = resonance phenomenon, and the durability of the product can be improved by preventing - a mechanical load to the rotating body 10 and the turbine, which is caused by the resonant © po phenomenon. Further, the electricity generating efficiency of the turbine can be “ improved by reducing a rotational force loss which otherwise may be generated due to the > resonance. oo Ny

FIG. 11 is a side cross-sectional view illustrating the sealing apparatus with a brush according to another embodiment of the present invention. In this embodiment, since the description of a basic configuration except a shape of a rear surface of a shock preventing portion 320 is the same as in the embodiment described above, description of the same portions will be omitted. )

As shown in FIG. 11, it is preferred that gaps between rear ends of throttling protrusions 322 and a front surface of a brush portion 330 become wider as it goes toward a lower side of the shock preventing portion 320.

Specifically, the fluid f introduced into the lower end of the shock preventing portion 320 is guided by guide holes 341 to be raised along a rear surface of the shock preventing portion 320. At this time, speed and pressure of the fluid f are reduced by passing through throttling protrusions 322 and throttling groove portions 321 disposed in multiple steps as the fluid goes toward an upper side.

When the fluid f having a decelerated speed is concentrated to the upper sided as described above, high pressure may be formed at an upper side of a brush portion 340.

That is, since the fluid flowing to the upper side has been subjected to a sufficient pressure drop, intervals between the throttling protrusions 322 at the upper side and the on Ca brush portion 340 are narrowly formed to accelerate the fluid f that is slow, and thereby - stagnation of the fluid can be prevented. 2

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Vibrations caused by a difference in velocity and pressure of the fluid in the inner w portion of the brush portion 340 can be prevented, by uniformly maintaining the velocity ’ and the pressure of the fluid passing through the upper portion and a lower portion of the w brush portion 340. Accordingly, the brush portion 340 can stably support the outer -! circumference of the rotating body 10, noise due to rotational vibration of the rotating : body 10 can be reduced, and rotational force loss and wear of inner part due to the ce vibration can be prevented.

Through this, the present invention provides the following effects.

First, the bristle plate supporting the rear side of the brush portion can improve the sealability by preventing the bristle plate from being bent to bring the bristles into close contact with the outer circumference of the rotating body. Further, since fluid pressure applied to each portion can be reduced by guiding the fluid through the guide holes to disperse the fluid to the entire brush portion, the amount 6f ledk of the fluid can be reduced, which allows the sealability to be increased, and reduction of rigidity of the brush portion due to the fluid pressure can be alleviated, which can improve durability.

Second, since the guide holes are provided to be upwardly inclined toward the casing so that the fluid passed through the inner portion thereof is guided away from the rotating body, the amount of the fluid flowing along the outer circumference of the rotating body can be reduced, thus the resistance between the fluid flowing in a different direction from the rotational direction and the rotating body can be reduced, and the rotational loss due to the vibration and frictional resistance can be prevented, thereby improving the electricity generating efficiency of the turbine.

Third, since the shock preventing portion is disposed to be spaced at a

A Cn predetermined interval in front of the brush portion, the fluid introduced into the - separated space is expanded, which allows the fluid pressure to be reduced, and the ~ amount of leak of the fluid is reduced by reducing pressure through the expansion and = repeated throttling of the fluid flowing upward by the guidance of the guide holes through ~ the throttling protrusions and the throttling groove portions disposed in multiple steps, - : thereby improving the sealing performance of the product. oo

While the embodiments of the present invention have been described above, the i present invention is not limited to each of the embodiments. It will be apparent to those ” skilled in the art that various modifications or alterations can be contrived and implemented within the scope described in the specification, and these modifications and alterations also fall within the technical scope of the present invention.

Claims

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1. A sealing apparatus with a brush, comprising: ot a sealing portion provided for a casing of a turbine to seal a flow of a fluid = leaking between the casing and a rotating body rotated in the casing; - fom a brush portion that is provided for the sealing portion and includes a plurality of = bristles disposed to surround an outer circumference of the rotating body; - i a shock preventing portion disposed to be spaced at a predetermined interval in be front of the brush portion so as to block a flow of the fluid flowing along the outer circumference of the rotating body; and a bristle plate that is provided to support a rear side of the brush portion and has a plurality of guide holes formed therethrough to be inclined upward toward the casing as it goes from an inflow direction to an outflow direction of the fluid, wherein the shock preventing portion includes a plurality of throttling protrusions protruding to a rear side to cause the fluid flowing upward along a rear surface facing the brush portion to be throttled, and throttling groove portions connecting the respective throttling protrusions which are disposed in multiple steps in an up and down direction of the shock preventing portion.

2. The sealing apparatus with the brush of claim 1, wherein each of the guide holes is disposed in an up and down direction and a circumference direction of the bristle plate, and a fluid inlet of the guide hole, which is formed at an uppermost side of the bristle plate, is disposed higher than the height at which the throttling protrusions formed at an uppermost side of the shock preventing portion.

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3. The sealing apparatus with the brush of claim 1, wherein the bristles are ~ provided to have a length that is long enough to come into contact with the outer © circumference of the rotating body to correspond to an interval between the casing and ~ the rotating body, and - the shock preventing portion and the bristle plate are provided to have lengths “ that are long enough to cause each of ends of the shock preventing portion and the bristle y plate to be spaced from the outer circumference of the rotating body. 2

4. The sealing apparatus with the brush of claim 1, wherein an end of the bristle plate is rounded, a first fluid flowing interval between the end of the bristle plate and the outer circumference of the rotating body is provided to be narrower than a second fluid flowing interval between the end of the shock preventing portion and the outer circumference of the rotating body.