Variable speed turbine low pressure blade

Abstract

The present application relates to the technical fields of variable speed turbine low-pressure moving vane, and discloses a variable speed turbine low-pressure moving vane, which comprises a blade root, the upper surface of the blade root is fixedly connected with a low-pressure moving vane body, the outer side surface of the low-pressure moving vane body is provided with a horn cover and a collecting cylinder, the inner cavity of the lower end of the horn cover is communicated with the inner cavity of the upper end of the collecting cylinder, the outer surface of the collecting cylinder is provided with a cleaning window, the inner side wall of the left end of the cleaning window is provided with a sealing mechanism, the outer surface of the collecting cylinder close to the right end of the cleaning window is fixedly connected with a baffle, the outer surfaces of the upper and lower ends of the baffle are provided with threaded holes one, and the inner surfaces of the threaded holes one are threadedly connected with bolts; through the cooperation of the above structure, the solid particles generated on the low-pressure moving vane body of the turbine after long-term use can be collected, and the solid particles can be avoided from entering into the hub as much as possible, so that the service life is improved.

Description

Technical Field

[0001] This invention belongs to the technical field of low-pressure moving blades for variable speed steam turbines, specifically a low-pressure moving blade for a variable speed steam turbine. Background Technology

[0002] During the operation of variable-speed steam turbines, the low-pressure moving blades, as core components, typically face complex operating conditions involving high temperature, high pressure, and high-speed rotation. Over extended periods of operation, solid particles formed from wear, oxidation, or foreign impurities gradually accumulate on the surface of the low-pressure moving blades and in the hub area. The presence of these solid particles not only exacerbates wear on the blade surface, leading to material fatigue and performance degradation, but may also penetrate the hub, causing jamming or damage to mechanical components, ultimately affecting the overall operating efficiency and reliability of the steam turbine.

[0003] Utility model patent CN221347036U discloses a low-pressure moving blade for a variable-speed steam turbine, including a blade root, a blade body connected above the blade root, and tie rod holes in the upper middle part of the blade body. The blade body is a torsion blade with a reference cross section. Based on the reference cross section, from the root section to the top section, the relative value of the cross section height Li monotonically increases from 0.0 to 1.21; the relative value of the installation angle C monotonically decreases from 3.49 to 0.76; the relative value of the cross-sectional area A monotonically decreases from 6.747 to 0.84; the relative value of the axial width Xa monotonically decreases from 3.12 to 0.81; the relative value of the chord length B monotonically decreases from 1.21 to 0.93 and then monotonically increases to 1.05; the relative value of the maximum thickness W monotonically decreases from 4.09 to 0.73; and the relative value of the outlet geometric angle α1 monotonically decreases from 1.75 to 0.78.

[0004] In the process of developing this application, the following problems were discovered with this technology: The aforementioned patent documents primarily focus on improving the strength and vibration performance of low-pressure dynamic blades through structural design optimization, but do not provide an effective solution to the problem of solid particle accumulation and removal. In practical applications, the continuous accumulation of solid particles can create a vicious cycle: on the one hand, particle adhesion to the blade surface can impair aerodynamic performance, increase flow resistance, and reduce power generation efficiency; on the other hand, particles entering the hub may trigger a chain of failures, such as bearing wear or seal failure, significantly shortening equipment lifespan.

[0005] Therefore, we propose a variable speed steam turbine low-pressure moving blade. Summary of the Invention

[0006] The purpose of this invention is to provide a variable speed steam turbine low-pressure moving blade that can collect solid particles generated on the low-pressure moving blade body of a steam turbine after long-term use, minimize the entry of solid particles into the hub, and improve service life.

[0007] The technical solution adopted in this invention is as follows:

[0008] A low-pressure moving blade for a variable-speed steam turbine includes a blade root. A low-pressure moving blade body is fixedly connected to the upper surface of the blade root. A horn cover and a collecting cylinder are installed on the outer side of the low-pressure moving blade body. The lower end of the horn cover and the upper end of the collecting cylinder are connected. A cleaning window is provided on the outer surface of the collecting cylinder. A sealing mechanism is installed on the inner wall of the left end of the cleaning window. A baffle is fixedly connected to the outer surface of the collecting cylinder near the right end of the cleaning window. A threaded hole is provided on the outer surface of the upper and lower ends of the baffle. A bolt is threaded to the inner surface of the threaded hole.

[0009] In a preferred embodiment of the invention, the sealing mechanism includes an arc-shaped plate, which is hinged to the inner wall of the left end of the cleaning window via a hinge. Two threaded holes are formed on the outer surface of the right end of the arc-shaped plate, and the inner surface of the threaded holes is threadedly connected to the bolt.

[0010] In a preferred embodiment of the invention, an arc-shaped groove is formed in the middle of the outer surface of the arc-shaped plate, and a connecting plate is fixedly connected to the inner sidewall of the arc-shaped groove.

[0011] In a preferred embodiment of the invention, a rubber pad is adhered to the upper outer surface of the speaker cover.

[0012] In a preferred embodiment of the invention, a rubber pad is adhered to the inner wall of the collecting cylinder.

[0013] In a preferred embodiment of the invention, the upper outer surface of the low-pressure moving blade body is provided with tie rod holes.

[0014] In a preferred embodiment of the invention, the collecting cylinder is generally in the shape of a semi-conical cylinder.

[0015] In a preferred embodiment of the invention, the upper opening of the horn cover has an arc-shaped cross-section.

[0016] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0017] 1. In this invention, when the low-pressure moving blade body of the steam turbine rotates, the horn cover can block solid particles near the hub. The blocked solid particles can enter the inside of the collection cylinder through the horn cover, minimizing the entry of solid particles into the hub. This allows for centralized cleaning of the solid particles collected inside the collection cylinder. Compared to CN221347036U, which simply improves strength and vibration performance, this application, through the combination of the above structures, can collect solid particles generated on the low-pressure moving blade body of the steam turbine after long-term use, minimizing the entry of solid particles into the hub and improving service life.

[0018] 2. In this invention, when it is necessary to clean the solid particles collected in the collection cylinder, the bolt can be rotated to remove it from the threaded holes one and two. Then, the arc-shaped plate can be pressed inward to open the cleaning window for cleaning the solid particles collected in the collection cylinder. After cleaning, the connecting plate can be held in place by fingers at the arc-shaped groove to seal the cleaning window. Then, the bolt can be rotated to connect it inside the threaded holes one and two, thereby sealing the cleaning window. Compared with the solid particles that move around in CN221347036U, this application, through the combination of the above structure, can regularly and conveniently clean the solid particles collected on the low-pressure moving blades of the steam turbine, thus improving service life. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of the present invention;

[0020] Figure 2 This is a schematic diagram of the structure of the horn cover, the collecting cylinder, and the sealing mechanism in this invention;

[0021] Figure 3 In this invention Figure 1 Enlarged view of point A;

[0022] Figure 4 This is a schematic diagram of the sealing mechanism in this invention;

[0023] Figure 5 This is a cross-sectional view of the present invention;

[0024] Figure 6 This is a cross-sectional view of the collection cylinder in this invention.

[0025] Explanation of reference numerals in the attached drawings: 1-Blade root; 2-Low-pressure moving blade body; 3-Flute cover; 4-Collection cylinder; 5-Sealing mechanism; 21-Stretcher hole; 31-Rubber pad one; 41-Rubber pad two; 42-Cleaning window; 43-Baffle; 44-Threaded hole one; 45-Bolt; 51-Arc plate; 52-Arc groove; 53-Connecting plate; 54-Threaded hole two. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0027] The following will combine Figures 1-6A detailed description of a low-pressure moving blade for a variable-speed steam turbine according to an embodiment of the present invention is provided.

[0028] Example 1:

[0029] Reference Figures 1-6 A variable-speed steam turbine low-pressure moving blade includes a blade root 1. A low-pressure moving blade body 2 is fixedly connected to the upper surface of the blade root 1. A tie rod hole 21 is opened on the upper outer surface of the low-pressure moving blade body 2. A horn cover 3 and a collection cylinder 4 are installed on the outer side of the low-pressure moving blade body 2. The upper opening section of the horn cover 3 is arc-shaped. The collection cylinder 4 has a semi-conical cylindrical structure. The lower inner cavity of the horn cover 3 is connected to the upper inner cavity of the collection cylinder 4. A cleaning window 42 is opened on the outer surface of the collection cylinder 4. A sealing mechanism 5 is installed on the inner wall of the left end of the cleaning window 42. A baffle 43 is fixedly connected to the outer surface of the collection cylinder 4 near the right end of the cleaning window 42. Threaded holes 44 are opened on the outer surfaces of the upper and lower ends of the baffle 43. The inner surface of the threaded holes 44 is threaded. Bolt 45 is attached; rubber pad 31 is adhered to the upper outer surface of the horn cover 3; rubber pad 41 is adhered to the inner wall of the collection cylinder 4; specifically, when the low-pressure moving blade body 2 of the steam turbine rotates, the horn cover 3 can block solid particles near the hub. The blocked solid particles can enter the inside of the collection cylinder 4 from the horn cover 3, minimizing the entry of solid particles into the hub, so that the solid particles collected inside the collection cylinder 4 can be centrally cleaned later. Compared with CN221347036U, which simply improves the strength and vibration performance, this application can collect solid particles generated on the low-pressure moving blade body 2 of the steam turbine after long-term use through the combination of the above structures, minimizing the entry of solid particles into the hub and improving service life.

[0030] Example 2:

[0031] Reference Figures 1-6The sealing mechanism 5 includes an arc-shaped plate 51, which is hinged to the inner wall of the left end of the cleaning window 42. Two threaded holes 54 are formed on the outer surface of the right end of the arc-shaped plate 51. The inner surface of the threaded holes 54 is threadedly connected to a bolt 45. An arc-shaped groove 52 is formed in the middle of the outer surface of the arc-shaped plate 51, and a connecting plate 53 is fixedly connected to the inner wall of the arc-shaped groove 52. Specifically, when it is necessary to clean the solid particles collected in the collection cylinder 4, the bolt 45 can be rotated to remove it from the threaded holes 44 and 54, and then the arc-shaped plate 51 can be pressed inward. The cleaning window 42 is opened to clean the solid particles collected in the collection cylinder 4. After cleaning, the connecting plate 53 can be held in place by the finger at the arc groove 52 to drive the arc plate 51 to seal the cleaning window 42. Then, the bolt 45 is rotated to connect the threaded hole 44 and the threaded hole 54, thereby sealing the cleaning window 42. Compared with the solid particles generated in CN221347036U that move around, this application can perform regular and convenient cleaning of the solid particles collected on the low-pressure moving blade body 2 of the steam turbine through the cooperation of the above structure, thereby improving the service life.

[0032] The implementation principle of the variable speed steam turbine low-pressure moving blade of this application is as follows:

[0033] When the low-pressure moving blade body 2 of the steam turbine rotates, the horn cover 3 can block solid particles near the hub. The blocked solid particles can enter the collection cylinder 4 through the horn cover 3, minimizing the entry of solid particles into the hub. This allows for centralized cleaning of the solid particles collected in the collection cylinder 4. Compared to CN221347036U, which simply improves strength and vibration performance, this application, through the combination of the above structures, can collect solid particles generated on the low-pressure moving blade body 2 of the steam turbine after long-term use, minimizing the entry of solid particles into the hub and improving service life.

[0034] When it is necessary to clean the solid particles collected in the collection cylinder 4, the bolt 45 can be rotated to remove it from the threaded hole 44 and the threaded hole 54. Then, the arc plate 51 can be pressed inward to open the cleaning window 42 for cleaning the solid particles collected in the collection cylinder 4. After cleaning, the connecting plate 53 can be held in place by the arc groove 52 to move the arc plate 51 to seal the cleaning window 42. Then, the bolt 45 can be rotated to connect it inside the threaded hole 44 and the threaded hole 54, thereby sealing the cleaning window 42. Compared with the solid particles generated in CN221347036U that move around, this application can use the above structure to clean the solid particles collected on the low-pressure moving blade body 2 of the steam turbine regularly and conveniently, thereby improving the service life.

[0035] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes the element.

[0036] 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 the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A low-pressure moving blade for a variable-speed steam turbine, comprising a blade root (1), characterized in that: The upper surface of the blade root (1) is fixedly connected to a low-pressure moving blade body (2). A horn cover (3) and a collection cylinder (4) are installed on the outer side of the low-pressure moving blade body (2). The lower end of the horn cover (3) and the upper end of the collection cylinder (4) are connected. A cleaning window (42) is opened on the outer surface of the collection cylinder (4). A sealing mechanism (5) is installed on the inner wall of the left end of the cleaning window (42). A baffle (43) is fixedly connected to the outer surface of the collection cylinder (4) near the right end of the cleaning window (42). A threaded hole (44) is opened on the outer surface of the upper and lower ends of the baffle (43). A bolt (45) is threadedly connected to the inner surface of the threaded hole (44).

2. The low-pressure moving blade of a variable-speed steam turbine according to claim 1, characterized in that: The sealing mechanism (5) includes an arc plate (51), which is hinged to the inner wall of the left end of the cleaning window (42) by a hinge. Two threaded holes (54) are opened on the outer surface of the right end of the arc plate (51), and the inner surface of the threaded holes (54) is threadedly connected to the bolt (45).

3. The low-pressure moving blade of a variable-speed steam turbine according to claim 2, characterized in that: An arc-shaped groove (52) is provided in the middle of the outer surface of the arc-shaped plate (51), and a connecting plate (53) is fixedly connected to the inner side wall of the arc-shaped groove (52).

4. The low-pressure moving blade of a variable-speed steam turbine according to claim 1, characterized in that: A rubber pad (31) is adhered to the upper outer surface of the speaker cover (3).

5. The low-pressure moving blade of a variable-speed steam turbine according to claim 1, characterized in that: The inner wall of the collecting cylinder (4) is bonded with a rubber pad (41).

6. The low-pressure moving blade of a variable-speed steam turbine according to claim 1, characterized in that: The upper outer surface of the low-pressure moving blade body (2) is provided with a tie rod hole (21).

7. The low-pressure moving blade of a variable-speed steam turbine according to claim 1, characterized in that: The collecting cylinder (4) has a semi-conical cylindrical structure.

8. The low-pressure moving blade of a variable-speed steam turbine according to claim 1, characterized in that: The upper opening of the horn cover (3) has an arc-shaped cross section.

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