A sealing sheet structure with cold air leakage slot

Abstract

The present invention provides a sealing sheet structure with a cold air leakage slot, comprising: a stationary blade assembly is sleeved on the rotor of a turbine; the stationary blade assembly comprises a holding ring and a plurality of stationary blades; a plurality of stationary blades in a circumferential array are arranged in the holding ring; the holding ring is composed of a plurality of retaining ring segments connected, and a stationary blade is connected under each retaining ring segment; a sealing sheet is arranged between every two retaining ring segments and every two stationary blade connection, and the sealing sheet is provided with a plurality of first air slots along its axial direction. The present invention increases the amount of cold air by arranging the first air slot on the sealing sheet at the connection between every two retaining ring segments and every two stationary blades, thereby reducing the phenomenon of ablation of the end wall platform and the retaining ring segment of the stationary blade.

Description

Technical Field

[0001] The invention relates to the technical field of gas turbine manufacturing, in particular to the technical field of a sealing sheet structure with a cold air leakage slot. Background Art

[0002] The purpose of gas turbine operation at high temperature is to improve thermal efficiency and power output. The heat transferred to the turbine blades increases with the increase of turbine inlet temperature, so the temperature level and thermal stress of each turbine component must be limited to ensure a reasonable life.

[0003] During the assembly of existing turbine blades, it is necessary to set a sealing sheet between the end wall platforms of two adjacent blades; the sealing sheet can prevent cold air from entering the stator blade end wall platform, thereby limiting the consumption of cooling air and improving the efficiency of the gas turbine; but on the other hand, due to the limitation of the consumption of cold air, it will cause the side of the stator blade end wall platform to be burned, thereby reducing the service life of the stator blade. Summary of the invention

[0004] In view of the above-mentioned shortcomings of the prior art, an object of the present invention is to provide a sealing sheet structure with a cold air leakage slot, so as to solve the problem in the prior art that it is difficult to balance the service life of the stationary blades and improve the efficiency of the gas turbine.

[0005] To achieve the above-mentioned and other related purposes, the present invention provides a sealing sheet structure with a cold air leakage slot, comprising:

[0006] A stationary blade assembly, wherein the stationary blade assembly is sleeved on the rotor of the turbine; the stationary blade assembly comprises a holding ring and a plurality of stationary blades; a plurality of stationary blades in a circumferential array are arranged in the holding ring; the holding ring is composed of a plurality of retaining ring segments connected together, and each retaining ring segment is connected to a stationary blade;

[0007] A sealing sheet is provided between every two sections of the guard ring sections and every two sections of the stationary blade connection, and the sealing sheet is provided with at least one first air gap along its axial direction.

[0008] Preferably, all the first air gaps are arranged in a zigzag shape, and each of the first air gaps has an inclination angle consistent with the axial direction, and the inclination angle is greater than 5° and less than 10°.

[0009] Preferably, the length of the first air gap is 20 to 30 mm.

[0010] Preferably, the sealing sheet is a quadrilateral structure.

[0011] Preferably, one side of the sealing sheet is a smooth plane, and the other end of the sealing sheet is a serrated surface.

[0012] Preferably, the sealing sheet is provided with a plurality of spaced half-open circular holes on both sides along the axial direction, and each of the half-open circular holes is provided with a second air gap; the second air gap is located between two adjacent first air gaps and is connected to the two adjacent first air gaps.

[0013] Preferably, the line between each of the half-open circular holes and the horizontal plane is an arc, and the distance from the closest point of the half-open circular hole toward the axis of the sealing strip to the side of the sealing strip is 1 mm.

[0014] Preferably, the second air gap is 1 or 1.5 times the length of the first air gap.

[0015] Preferably, the distance between the centers of each two adjacent arcs is 5 to 10 mm greater than the length of the second air gap.

[0016] As described above, the sealing sheet structure with a cold air leakage slot of the present invention has the following beneficial effects:

[0017] The present invention can prevent high-temperature combustion gas from entering the holding ring or the connection between two stationary blades by arranging the first air slit on the sealing sheet, and at the same time allow cooling air to enter the stationary blade, thereby preventing ablation on the side of the stationary blade end wall platform; in addition, the sealing sheet is provided with a second air slit on the side to absorb the cold air on both sides of the sealing sheet, further increasing the inflow of cooling air. In addition, the sealing sheet staggers at least one first air slit and arranges it at intervals in the axial direction of the sealing sheet, which can ensure that the cold air leaks evenly into the gaps between adjacent stationary blades, avoiding uneven distribution of local heat loads. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram showing the installation of a sealing sheet structure with a cold air leakage slot, a stationary blade and a holding ring according to the present invention;

[0019] Figure 2 A perspective view showing a first embodiment of a sealing sheet structure with a cold air leakage slot according to the present invention from one angle;

[0020] Figure 3 A three-dimensional view showing another angle of the first embodiment of a sealing sheet structure with a cold air leakage slot according to the present invention;

[0021] Figure 4 A top view of a first embodiment of a sealing sheet structure with a cold air leakage slot according to the present invention is shown;

[0022] Figure 5 A side view showing a first embodiment of a sealing sheet structure with a cold air leakage slot according to the present invention;

[0023] Figure 6A top view showing a second embodiment of a sealing sheet structure with a cold air leakage slot according to the present invention;

[0024] Figure 7 A side view of a second embodiment of a sealing sheet structure with a cold air leakage slot according to the present invention is shown.

[0025] Component number description

[0026] 11. Ring Holder

[0027] 111 guard ring section

[0028] 12 Stationary blades

[0029] 2 Sealing sheet

[0030] 21 First air gap

[0031] 22 Smooth surface

[0032] 23. Sawtooth surface

[0033] 24 Half-open round hole

[0034] 241 Second Air Seam DETAILED DESCRIPTION

[0035] The following is a description of the implementation of the present invention by means of specific embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification.

[0036] See also Figures 1 to 7 . It should be noted that the structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the limiting conditions for the implementation of the present invention, so they have no substantial technical significance. Any modification of the structure, change in the proportional relationship, or adjustment of the size should still fall within the scope of the technical content disclosed by the present invention without affecting the effects and purposes that can be achieved by the present invention. At the same time, the terms such as "upper", "lower", "left", "right", "middle" and "one" quoted in this specification are only for the convenience of description, and are not used to limit the scope of the implementation of the present invention. Changes or adjustments in their relative relationships should also be regarded as the scope of the implementation of the present invention without substantially changing the technical content.

[0037] like Figure 1 As shown, the present invention provides a sealing sheet structure with a cold air leakage slot, comprising:

[0038] The stationary blade assembly is sleeved on the rotor of the turbine; the stationary blade assembly includes a holding ring 11 and a plurality of stationary blades 12; a plurality of stationary blades 12 in a circumferential array are arranged in the holding ring 11; the holding ring 11 is composed of a plurality of retaining ring segments 111 connected together, and a stationary blade 12 is connected under each retaining ring segment 111;

[0039] A sealing sheet 2 is provided between each two sections of the retaining ring sections 111 and each two sections of the stationary blades 12 , and the sealing sheet 2 is provided with at least one first air gap 21 along its axial direction.

[0040] The present invention increases the amount of cooling air by providing a first air gap 21 on the sealing sheet 2 at the connection between every two sections of the retaining ring sections 111 and every two sections of the stationary blades 12, thereby reducing the ablation phenomenon of the end wall platform of the stationary blade 12 and the retaining ring section 111; in addition, at the same time, the sealing sheet 2 still has a sealing effect to effectively block the invasion of high-temperature fuel gas.

[0041] The first embodiment of the present invention, see Figures 1 to 5 As shown:

[0042] like Figure 4 As shown, in order to allow the cold air to leak evenly into the gaps of the adjacent stationary blades 12, so as to achieve the purpose of cooling the end wall of the stationary blade 12; now all the first air gaps 21 are arranged in a zigzag shape, and each first air gap 21 has a consistent inclination angle with the axial direction, and the inclination angle θ is greater than 5° and less than 10°. When the cold air passes through the first air gap 21, it can leak evenly into the gap between the two stationary blades 12, avoiding the influence of the cooling of the stationary blade 12 due to overcooling, too slow or too fast.

[0043] In order to allow each first air gap 21 to leak enough cold air, Figure 4 As shown, the length a of the first air gap 21 is now set to 20 to 30 mm. In addition, in order to allow the second air gap 241 to introduce more cold air, the length b of the second air gap 241 is now set to 0.5 to 2 times the length of the first air gap 21, that is, 0.5≤b≤2a.

[0044] In order to simplify the processing of the sealing sheet 2, the sealing sheet 2 is now set to a quadrilateral structure.

[0045] In order to prevent the sealing sheet 2 from falling off when it is inserted into the connection between each two sections of the retaining ring section 111 and each two sections of the stationary blade 12; Figure 2 and 3 As shown, one side of the sealing strip 2 is a smooth plane 22, and the other end of the sealing sheet 2 is a serrated surface 23. The serrated surface 23 can increase a certain friction force, so that the sealing sheet 2 and the cavity are more tightly connected.

[0046] In order to further improve the leakage of cold air from one side of the sealing plate 2 to the other side, a plurality of spaced half-open circular holes 24 are provided on both sides of the sealing plate 2 along the axial direction, and a second air gap 241 is provided on the wall of each half-open circular hole 24; the second air gap 241 is located between two adjacent first air gaps 21 and is connected to the two adjacent first air gaps 21. Figure 1 As shown, when the sealing sheet 2 is disposed between the two retaining ring sections 111, cold air can flow from the second air gap 241 on the side of the sealing sheet 2 through the first air gap 21 to the bottom of the sealing sheet 2; Figure 1 As shown, when the sealing sheet 2 is disposed between the connection points of two sections of stationary blades 12 , cold air can flow from the second air gap 241 on the side of the sealing sheet 2 through the first air gap 21 to the top of the sealing sheet 2 .

[0047] In order to avoid the loss of the isolation effect of the sealing strip 2 caused by excessive cutting of the side of the sealing strip 2, the side of the sealing strip 2 can be partially cut to control the cutting amount; specifically, Figure 4 As shown, the distance from point A, where the semi-open circular hole 24 is closest to the axis of the sealing strip 2, to the side of the sealing strip 2 is 1 mm.

[0048] To illustrate the profile of the half-open circular hole 24, the coincidence line of the half-open circular hole 24 and the horizontal plane is an arc, and the radius r of the arc is equal to the distance c from the center of the arc to the side of the sealing strip 2 plus 1 mm, that is, r = c + 1;

[0049] In order to limit the distance between two adjacent semicircular holes 24, the distance between the centers of two adjacent arcs is limited; specifically, the distance between the centers of the two adjacent arcs is 2e, and half of 2e is 5 to 10 mm larger than the length b of the second air gap, that is, e=b+(5~10) mm.

[0050] The second embodiment of the present invention is shown in Figure 6 and 7 :

[0051] The difference between the second embodiment and the first embodiment is that: Figure 6 As shown, in order to simplify the arrangement of the first air slots 21 , all the first air slots 21 may be arranged at intervals along the axis.

[0052] When all the first air gaps 21 are arranged along the axis, in order to still allow the second air gaps 241 on both sides of the first air gap 21 to penetrate it, the length a of the first air gap 21 needs to be shortened while e and b remain unchanged, such as Figure 6 shown.

[0053] Or when the lengths of a and b need to remain unchanged, the distribution of the half-open circular holes 24 on both sides can be changed to satisfy the formula e=b+(0-5).

[0054] In summary, the present invention can prevent high-temperature combustion gas from entering the holding ring or the connection between two stationary blades by setting the first air slit 21 on the sealing sheet 2, and at the same time allow cooling air to enter the stationary blade, thereby avoiding ablation on the side of the stationary blade end wall platform; in addition, the sealing sheet 2 is provided with a second air slit 241 on the side to absorb the cold air on both sides of the sealing sheet 2, further increasing the inflow of cooling air. In addition, the sealing sheet 2 staggers all the first air slits 21, and is spaced apart in the axial direction of the sealing sheet 2, which can ensure that the cold air leaks evenly into the gaps between adjacent stationary blades, avoiding uneven distribution of local heat loads.

[0055] Therefore, the present invention effectively overcomes various shortcomings in the prior art and has high industrial utilization value.

[0056] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A sealing sheet structure with a cold air leakage slot, It is characterized in that include: A stationary blade assembly, wherein the stationary blade assembly is sleeved on the rotor of the turbine; the stationary blade assembly comprises a holding ring and a plurality of stationary blades; A plurality of the stationary blades in a circular array are arranged in the holding ring; the holding ring is composed of a plurality of guard ring segments connected together, and each guard ring segment is connected to a stationary blade; A sealing sheet, wherein the sealing sheet is provided between every two sections of the retaining ring sections and between every two sections of the stationary blades, and the sealing sheet is provided with at least one first air gap along its axial direction; All the first air slits are arranged in a zigzag shape, and each of the first air slits has an inclination angle consistent with the axial direction, and the inclination angle is greater than 5° and less than 10°. When the cold air passes through the first air slits, it leaks evenly into the gap between the two stationary blades; In order to increase the leakage of cold air from one side of the sealing plate to the other side, the sealing plate is provided with a plurality of spaced half-open circular holes on both sides along the axial direction, and a second air gap is provided at each half-open circular hole; the second air gap is located between two adjacent first air gaps, and is connected with two adjacent first air gaps. When the sealing plate is arranged between two sections of the protective ring sections, the cold air flows from the second air gap on the side of the sealing plate to the bottom of the sealing plate via the first air gap; when the sealing plate is arranged between the connection of two sections of stationary blades, the cold air flows from the second air gap on the side of the sealing plate to the top of the sealing plate via the first air gap.

2. A sealing sheet structure with a cold air leakage slot according to claim 1, It is characterized in that The length of the first air gap is 20 to 30 mm.

3. A sealing sheet structure with a cold air leakage slot according to claim 1, Features: The sealing sheet is a quadrilateral structure.

4. A sealing sheet structure with a cold air leakage slot according to claim 1, Features: One side of the sealing sheet is a smooth plane, and the other end of the sealing sheet is a serrated surface.

5. A sealing sheet structure with a cold air leakage slot according to claim 1, Features: The line between each of the half-open circular holes and the horizontal plane is an arc, and the distance from the closest point of the half-open circular hole toward the axis of the sealing sheet to the side surface of the sealing sheet is 1 mm.

6. A sealing sheet structure with a cold air leakage slot according to claim 1, Features: The second air gap has a length that is 1 or 1.5 times that of the first air gap.

7. A sealing sheet structure with a cold air leakage slot according to claim 5, Features: The distance between the centers of each two adjacent arcs is 5 to 10 mm greater than the length of the second air gap.

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