A steam turbine steam seal arrangement to prevent backside leakage

Abstract

This invention relates to the technical field of steam sealing, and discloses a steam sealing device for a steam turbine to prevent back leakage. It includes an output mechanism, a rotor, a convex ring fixedly connected to the outside of the rotor, and an installation mechanism disposed on the outside of the rotor. The installation mechanism includes a mounting bracket disposed on the outside of the rotor and a connecting plate fixedly connected to the outside of the mounting bracket. By using a sealing method where the steam sealing ring and the mounting groove are pressed together, compared to the traditional point-to-surface contact sealing method, the sealing effect on steam can be effectively improved. Combined with the design of the arc-shaped groove on the outer side of the cylinder and the design of the inclined air plate, the high-pressure steam swirls inside the mounting groove. Furthermore, the inclination direction of the air plate and the arc-shaped groove are opposite, resulting in different swirling directions of the two high-pressure steam streams. This causes the high-pressure steam to continuously collide with each other, reducing the intensity of the high-pressure steam entering the mounting groove and preventing steam leakage.

Description

Technical Field

[0001] This invention relates to the technical field of steam sealing, and more particularly to a steam sealing device for a steam turbine to prevent back leakage. Background Technology

[0002] Steam turbines are one of the core pieces of equipment in thermal power plants, converting the thermal energy of steam into the mechanical energy of the rotor. To reduce steam leakage losses at the tips and roots of the moving and stationary blades and improve the turbine's thermal energy conversion efficiency, steam sealing devices are installed at these locations during the energy conversion process.

[0003] A steam sealing device typically consists of four or six steam sealing arc segments forming a ring structure. These segments are installed within diaphragm grooves. The back boss of each arc segment mates with the diaphragm groove to position the device. The high and low teeth of the steam sealing device, along with the sealing teeth on the rotor, form a labyrinth seal, throttling and reducing the pressure of the high-pressure steam to minimize steam leakage. Generally, the back bosses of the arc segments and the diaphragm grooves of the steam sealing device are machined with very precision to form a contact seal, preventing high-pressure steam from leaking from the back of the device.

[0004] Currently, when adjusting the steam seal gap between the steam seal device and the rotor, the common method is to scrape the steam seal back boss or raise the steam seal back boss. This often overlooks the steam leakage problem at the back of the steam seal device. Raising the steam seal back boss changes the contact seal between the steam seal back boss and the partition groove into a point seal, resulting in a large gap at the mating parts. A large amount of high-pressure steam leaks from the back of the steam seal device, causing steam leakage loss. Summary of the Invention

[0005] In view of the problems existing in the prior art, the present invention is proposed.

[0006] Therefore, the purpose of this invention is to provide a steam sealing device for a steam turbine that prevents back leakage. Its purpose is to ensure that the sealing performance for high-pressure steam can still be guaranteed even after the back protrusion of the steam seal is raised.

[0007] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a steam sealing device for preventing back leakage in a steam turbine, comprising,

[0008] The output mechanism includes a rotor, a convex ring fixedly connected to the outside of the rotor, and a mounting mechanism disposed on the outside of the rotor.

[0009] The mounting mechanism includes a mounting bracket disposed on the outside of the rotor, a connecting plate fixedly connected to the outside of the mounting bracket, and bolts threadedly connected to the inside of the connecting plate. The mounting bracket has a mounting groove on its inner side, and a steam seal component is adapted to be installed inside the mounting groove.

[0010] As a preferred embodiment of the turbine steam sealing device for preventing back leakage according to the present invention, the steam sealing component includes a steam sealing ring adapted to be installed inside the mounting groove, high comb teeth fixedly connected to the inner side of the steam sealing ring, and bottom comb teeth fixedly connected to the inner side of the high comb teeth.

[0011] The outer side of the gas seal ring is fixedly connected with a protrusion.

[0012] As a preferred embodiment of the turbine steam sealing device for preventing back leakage according to the present invention, the steam sealing component further includes a plate fixedly connected to the outside of the steam sealing ring and a ball fixedly connected to the outside of the plate.

[0013] As a preferred embodiment of the turbine steam sealing device for preventing back leakage according to the present invention, wherein: a sliding cavity is provided on one side of the steam sealing ring, an inner cavity is provided inside the steam sealing ring, a bottom cavity is provided on the outer side of the insert plate, a fastening component is adapted to be installed inside the sliding cavity, and a return component is adapted to be installed inside the bottom cavity.

[0014] As a preferred embodiment of the turbine steam sealing device for preventing back leakage according to the present invention, the fastening assembly includes a slide rod slidably connected inside the slide cavity, a pressure block fixedly connected to one end of the slide rod, and a slider fixedly connected to the other end of the slide rod.

[0015] The slider is slidably connected inside the inner cavity.

[0016] As a preferred embodiment of the turbine steam sealing device for preventing back leakage according to the present invention, the fastening assembly further includes a first spring sleeved on the outside of the slide bar, a circular hole opened on the outside of the slider, and a locking element disposed inside the circular hole.

[0017] The first spring is disposed inside the sliding cavity.

[0018] As a preferred embodiment of the turbine steam sealing device for preventing back leakage according to the present invention, the locking element includes a second spring fixedly connected to the bottom end of the circular hole, and a cylinder fixedly connected to one end of the second spring.

[0019] As a preferred embodiment of the turbine steam sealing device for preventing back leakage according to the present invention, the locking member further includes an arc-shaped groove formed on the outer side of the cylinder and a slot formed on the inner wall of the arc-shaped groove.

[0020] The arc-shaped groove is designed to be inclined.

[0021] As a preferred embodiment of the turbine steam sealing device for preventing back leakage according to the present invention, the reflux assembly includes a rotating shaft rotatably connected inside the bottom cavity and a wind plate fixedly connected to the outside of the rotating shaft, and a torsion spring is provided inside the rotating shaft.

[0022] As a preferred embodiment of the turbine steam sealing device for preventing back leakage according to the present invention, the reflux assembly further includes a telescopic rod hinged to the outside of the rotating shaft, and a locking rod hinged to the telescopic end of the telescopic rod, wherein the locking rod is slidably connected to the top of the bottom cavity.

[0023] The beneficial effects of this invention are as follows: By using the compression sealing method between the steam sealing ring and the mounting groove, compared with the traditional point-to-surface contact sealing method, the sealing effect of steam can be effectively improved. Combined with the design of the arc groove on the outer side of the cylinder and the design of the inclined air plate, the high-pressure steam is made to swirl inside the mounting groove. Furthermore, the inclination direction of the air plate and the arc groove are opposite, so the two swirling high-pressure steam have different swirling directions, causing the high-pressure steam to collide with each other continuously, reducing the intensity of high-pressure steam entering the mounting groove and preventing steam leakage. Attached Figure Description

[0024] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Wherein:

[0025] Figure 1 This is a schematic diagram of the overall structure of the present invention.

[0026] Figure 2 This is a schematic diagram of the internal structure of the present invention.

[0027] Figure 3 This is an enlarged structural diagram of part A of the present invention.

[0028] Figure 4 This is a schematic diagram of the overall structure of the gas seal component of the present invention.

[0029] Figure 5 This is a partial cross-sectional structural diagram of the present invention.

[0030] Figure 6 This is an enlarged structural diagram of part B of the present invention.

[0031] Figure 7 This is a schematic diagram of a single structure of the gas seal component of the present invention.

[0032] Figure 8This is a schematic diagram of the fastening component structure of the present invention.

[0033] Figure 9 This is an enlarged structural diagram of part C of the present invention.

[0034] Figure 10 This is a schematic diagram of the recirculation component structure of the present invention.

[0035] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0036] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0037] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that is mutually exclusive with other embodiments.

[0038] Secondly, the present invention is described in detail with reference to the schematic diagrams. When detailing the embodiments of the present invention, for ease of explanation, the cross-sectional views illustrating the device structure may be partially enlarged, not according to the usual scale. Furthermore, the schematic diagrams are merely examples and should not limit the scope of protection of the present invention. In addition, actual fabrication should include three-dimensional spatial dimensions of length, width, and depth.

[0039] Example 1

[0040] Reference Figures 1 to 8 This is the first embodiment of the present invention, which provides a steam sealing device for preventing back leakage in a steam turbine. This device includes...

[0041] The output mechanism 100 includes a rotor 101, a protruding ring 102 fixedly connected to the outside of the rotor 101, and a mounting mechanism 200 disposed on the outside of the rotor 101.

[0042] The mounting mechanism 200 includes a mounting bracket 201 disposed on the outside of the rotor 101, a connecting plate 202 fixedly connected to the outside of the mounting bracket 201, and a bolt 203 threadedly connected to the inside of the connecting plate 202. The mounting bracket 201 has a mounting groove 204 on its inner side, and a steam seal component 205 is fitted inside the mounting groove 204.

[0043] Specifically, the steam seal component 205 includes a steam seal ring 205a adapted to be installed inside the mounting groove 204, a high comb tooth 205b fixedly connected to the inner side of the steam seal ring 205a, and a bottom comb tooth 205c fixedly connected to the inner side of the high comb tooth 205b.

[0044] Among them, the outer side of the steam seal ring 205a is fixedly connected with a protrusion 205d.

[0045] Furthermore, the steam seal component 205 also includes a plate 205e fixedly connected to the outside of the steam seal ring 205a and a ball 205f fixedly connected to the outside of the plate 205e.

[0046] Furthermore, a sliding cavity 205g is provided on one side of the steam seal ring 205a, an inner cavity 205h is provided inside the steam seal ring 205a, a bottom cavity 205i is provided on the outer side of the insert plate 205e, a fastening component 205j is adapted to be installed inside the sliding cavity 205g, and a return component 205k is adapted to be installed inside the bottom cavity 205i.

[0047] Preferably, the fastening assembly 205j includes a slide rod 205j-1 slidably connected inside the slide cavity 205g, a pressure block 205j-2 fixedly connected to one end of the slide rod 205j-1, and a slider 205j-3 fixedly connected to the other end of the slide rod 205j-1.

[0048] Among them, slider 205j-3 is slidably connected inside the inner cavity 205h.

[0049] It should be noted that the fastening assembly 205j also includes a first spring 205j-4 sleeved on the outside of the slide bar 205j-1, a round hole 205j-5 opened on the outside of the slider 205j-3, and a locking member 205j-6 disposed inside the round hole 205j-5.

[0050] The first spring 205j-4 is located inside the sliding cavity 205g.

[0051] In use, after fixing the ball 205f on the outside of the insert 205e of the steam seal ring 205a to achieve the steam seal gap between the whole steam seal device and the rotor, the two sets of steam seal rings 205a are installed inside the mounting groove 204 through the insert 205e, and then the two sets of mounting brackets 201 are fixedly connected by using bolts 203.

[0052] When the steam seal ring 205a is installed inside the mounting groove 204 of the mounting bracket 201, it will cause one side of the pressure block 205j-2 to be squeezed by the inner wall of the mounting groove 204. Under the reaction force of the first spring 205j-4 sleeved on the outside of the slide rod 205j-1, the steam seal ring 205a will be shifted to one side inside the mounting groove 204, so that the protrusion 205d can completely squeeze and seal with the inner wall of the mounting groove 204.

[0053] Even after the ball 205f is fixed to the outside of the panel 205e, the steam sealing ring 205a and the mounting groove 204 can still be sealed. Compared with the traditional point-to-surface contact method, this can effectively improve the sealing effect of steam. When high-pressure steam is input, the thrust of the high-pressure steam can once again compress the steam sealing ring 205a, thereby further improving the compression sealing effect of the protrusion 205d and the mounting groove 204.

[0054] In summary, the method of sealing by extruding the steam seal ring 205a with the mounting groove 204 can effectively improve the sealing effect of steam compared with the traditional point-to-surface contact sealing method.

[0055] Example 2

[0056] Reference Figure 9 This is the second embodiment of the present invention. The difference between this embodiment and the first embodiment is that the locking member 205j-6 includes a second spring 205j-6a fixedly connected to the bottom end of the circular hole 205j-5, and a cylinder 205j-6b fixedly connected to one end of the second spring 205j-6a.

[0057] Furthermore, the locking component 205j-6 also includes an arc-shaped groove 205j-6c formed on the outer side of the cylinder 205j-6b, and a slot 205j-6d formed on the inner wall of the arc-shaped groove 205j-6c;

[0058] Among them, the arc groove 205j-6c is designed with an inclination.

[0059] In use, when the mounting bracket 201 slides in the opposite direction under the elasticity of the first spring 205j-4, it will cause the slider 205j-3 to slide inside the inner cavity 205h, which will cause the cylinder 205j-6b inside the round hole 205j-5 to be located at the through hole inside the inner cavity 205h. Under the elasticity of the second spring 205j-6a, the cylinder 205j-6b will be driven to extend through the through hole, and the extended cylinder 205j-6b will press the air plate 205k-2, causing the air plate 205k-2 to rotate around the rotating shaft 205k-1, causing the torsion spring inside the rotating shaft 205k-1 to deform.

[0060] When some of the high-pressure steam enters the interior of the mounting groove 204 through the gap between the mounting groove 204 and the pressure block 205j-2, the arc-shaped groove 205j-6c on the side of the cylinder 205j-6b and the inclined design of the arc-shaped groove 205j-6c will cause the high-pressure steam to swirl when it flows towards the surface of the arc-shaped groove 205j-6c. This will reduce the intensity of the high-pressure steam entering the mounting groove 204 and prevent the high-pressure steam from being squeezed into the sealing surface on the side with the protrusion 205d, thus preventing steam leakage.

[0061] In summary, the method of sealing by compression between the steam sealing ring 205a and the mounting groove 204, compared with the traditional point-to-surface contact sealing method, can effectively improve the sealing effect of steam. Combined with the design of the arc groove 205j-6c on the outer side of the cylinder 205j-6b, the high-pressure steam swirls inside the mounting groove 204, reducing the intensity of high-pressure steam entering the mounting groove 204 and preventing steam leakage.

[0062] Example 3

[0063] Reference Figure 10 This is the third embodiment of the present invention. The difference between this embodiment and the second embodiment is that the return assembly 205k includes a rotating shaft 205k-1 rotatably connected inside the bottom cavity 205i, and a wind plate 205k-2 fixedly connected to the outside of the rotating shaft 205k-1. A torsion spring is provided inside the rotating shaft 205k-1.

[0064] Furthermore, the reflux assembly 205k also includes a telescopic rod 205k-3 hinged to the outside of the rotating shaft 205k-1, and a locking rod 205k-4 hinged to the telescopic end of the telescopic rod 205k-3, the locking rod 205k-4 being slidably connected to the top of the bottom cavity 205i.

[0065] When in use, when the air plate 205k-2 is squeezed by the cylinder 205j-6b and rotates around the pivot 205k-1, it will drive the locking rod 205k-4 to slide inside the bottom cavity 205i with the cooperation of the telescopic rod 205k-3, thereby causing the locking rod 205k-4 to approach the locking groove 205j-6d;

[0066] After the high-pressure steam enters the mounting groove 204, it blows the inclined air plate 205k-2 and causes the air plate 205k-2 to continue to rotate around the rotating shaft 205k-1 until one side of the air plate 205k-2 contacts the inner wall of the mounting groove 204. At this time, the rotating shaft 205k-1 will continue to drive the locking rod 205k-4 to continue to slide and insert into the locking groove 205j-6d, thereby fixing the cylinder 205j-6b and ensuring the stability of the steam seal ring 205a after extrusion.

[0067] Furthermore, since the air deflector 205k-2 is inclined inside the mounting groove 204, it can guide the high-pressure steam entering the mounting groove 204, causing the high-pressure steam to swirl. This further reduces the intensity of the high-pressure steam entering the mounting groove 204. Moreover, the inclination direction of the air deflector 205k-2 is opposite to that of the arc groove 205j-6c, resulting in different swirling directions of the two high-pressure steam streams. This causes the high-pressure steam to continuously collide with each other, effectively reducing the intensity of the high-pressure steam entering the mounting groove 204 and preventing the high-pressure steam from being squeezed into the sealing surface on the side with the protrusion 205d, thus avoiding steam leakage.

[0068] In summary, the compression sealing method using the steam sealing ring 205a and the mounting groove 204 effectively improves the sealing effect of steam compared to the traditional point-to-surface contact sealing method. Combined with the design of the outer arc groove 205j-6c of the cylinder 205j-6b and the inclined air plate 205k-2, the high-pressure steam swirls inside the mounting groove 204. Furthermore, the inclination directions of the air plate 205k-2 and the arc groove 205j-6c are opposite, resulting in different swirling directions of the two high-pressure steam streams. This causes the high-pressure steam to continuously collide with each other, reducing the intensity of high-pressure steam entering the mounting groove 204 and preventing steam leakage.

[0069] It is important to note that the constructions and arrangements of this application shown in several different exemplary embodiments are merely illustrative. Although only a few embodiments are described in detail in this disclosure, those who consult this disclosure will readily understand that many modifications are possible (e.g., changes in the size, dimensions, structure, shape, and proportions of various elements, as well as parameter values ​​(e.g., temperature, pressure, etc.), mounting arrangements, use of materials, color, orientation, etc.) without substantially departing from the novel teachings and advantages of the subject matter described in this application). For example, an element shown as integrally formed may be composed of multiple parts or elements, the position of elements may be inverted or otherwise altered, and the nature or number or position of discrete elements may be changed or altered. Therefore, all such modifications are intended to be included within the scope of the invention. The order or sequence of any process or method steps may be changed or rearranged according to alternative embodiments. In the claims, any "device plus function" clause is intended to cover the structure described herein that performs the function, and not only structurally equivalent but also equivalent in structure. Other substitutions, modifications, alterations, and omissions may be made in the design, operation, and arrangement of the exemplary embodiments without departing from the scope of the invention. Therefore, the present invention is not limited to the specific embodiments, but extends to various modifications that still fall within the scope of the appended claims.

[0070] Furthermore, in order to provide a concise description of exemplary embodiments, not all features of actual embodiments (i.e., those features that are not relevant to the currently considered best mode for carrying out the invention, or those features that are not relevant to implementing the invention) may be omitted.

[0071] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A steam turbine steam seal arrangement to prevent backside leakage, characterized by: include, The output mechanism (100) includes a rotor (101), a protruding ring (102) fixedly connected to the outside of the rotor (101), and a mounting mechanism (200) disposed on the outside of the rotor (101). The mounting mechanism (200) includes a mounting bracket (201) disposed on the outside of the rotor (101), a connecting plate (202) fixedly connected to the outside of the mounting bracket (201), and a bolt (203) threadedly connected to the inside of the connecting plate (202). The mounting bracket (201) has a mounting groove (204) on its inner side, and a steam seal component (205) is adapted to be installed inside the mounting groove (204). The vapor seal component (205) includes a vapor seal ring (205a) adapted to be installed inside the mounting groove (204), and a plate (205e) fixedly connected to the outside of the vapor seal ring (205a). A sliding cavity (205g) is provided on one side of the steam seal ring (205a), an inner cavity (205h) is provided inside the steam seal ring (205a), a bottom cavity (205i) is provided on the outer side of the insert plate (205e), a fastening component (205j) is adapted to be installed inside the sliding cavity (205g), and a return flow component (205k) is adapted to be installed inside the bottom cavity (205i). The fastening assembly (205j) includes a slide rod (205j-1) slidably connected inside the slide cavity (205g), a pressure block (205j-2) fixedly connected to one end of the slide rod (205j-1), and a slider (205j-3) fixedly connected to the other end of the slide rod (205j-1). The slider (205j-3) is slidably connected inside the inner cavity (205h); The fastening assembly (205j) also includes a first spring (205j-4) sleeved on the outside of the slide bar (205j-1), a round hole (205j-5) opened on the outside of the slider (205j-3), and a locking member (205j-6) disposed inside the round hole (205j-5). The first spring (205j-4) is disposed inside the sliding cavity (205g); The locking component (205j-6) includes a second spring (205j-6a) fixedly connected to the bottom end of the circular hole (205j-5), and a cylinder (205j-6b) fixedly connected to one end of the second spring (205j-6a). The locking component (205j-6) also includes an arc-shaped groove (205j-6c) formed on the outer side of the cylinder (205j-6b) and a slot (205j-6d) formed on the inner wall of the arc-shaped groove (205j-6c). The arc-shaped groove (205j-6c) is designed to be inclined. The return assembly (205k) includes a rotating shaft (205k-1) rotatably connected inside the bottom cavity (205i), and a wind vane (205k-2) fixedly connected to the outside of the rotating shaft (205k-1), and a torsion spring is provided inside the rotating shaft (205k-1). The reflux assembly (205k) also includes a telescopic rod (205k-3) hinged to the outside of the rotating shaft (205k-1), and a locking rod (205k-4) hinged to the telescopic end of the telescopic rod (205k-3), the locking rod (205k-4) being slidably connected to the top of the bottom cavity (205i).

2. The turbine steam seal to prevent backside leakage as claimed in claim 1, wherein: The steam seal component (205) further includes high comb teeth (205b) fixedly connected to the inner side of the steam seal ring (205a), and bottom comb teeth (205c) fixedly connected to the inner side of the high comb teeth (205b). The outer side of the steam seal ring (205a) is fixedly connected with a protrusion (205d).

3. The turbine steam seal to prevent backside leakage as claimed in claim 2 wherein: The gas seal component (205) also includes a ball (205f) fixedly connected to the outside of the panel (205e).

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