Turbine guide vane positioning structure and turbine

Abstract

The invention provides a turbine guide vane positioning structure which is arranged at the joint of a guide vane hook, a turbine outer ring and a turbine case and comprises a positioning block, a first groove, a second groove and an axial positioning part, and the first groove is formed in the guide vane hook; the second groove is formed in the turbine case and is opposite to the first groove in the radial direction, and a containing cavity for containing at least part of the positioning block is defined; the axial positioning part is arranged on the turbine outer ring and used for fixing the positioning block together with the guide vane hook and the turbine outer ring. The turbine guide vane positioning structure has better guide vane assembly efficiency on the premise of ensuring the stability of the guide vane in the circumferential direction. The invention further provides a turbine comprising the turbine guide vane positioning structure.

Description

Technical Field

[0001] The invention relates to the field of aeroengines, and in particular to the field of blade positioning bumps. Background Art

[0002] The Low Pressure Turbine is the main gas power extraction component in the engine. Its function is to convert the potential energy of the gas into mechanical kinetic energy. The output power drives the fan rotor to rotate and do work on the air. The guide vane (NozzleSegment) is the stator component of the gas turbine engine turbine. It accelerates the airflow at the outlet of the front row of moving blades and changes the direction of the airflow to impact the rear row of moving blades at the required angle. The Low Pressure Turbine Case is the containment structure outside the low pressure turbine component, providing a fixed assembly position for the low pressure turbine guide vanes and the outer ring. The low pressure turbine outer ring (Low Pressure Turbine Shroud Segment) is the middle case structure between the low pressure turbine case and the rotor blades.

[0003] The guide vanes of each stage of the low-pressure turbine are an annular stationary cascade composed of an inner edge plate, an outer edge plate and a group of guide vanes. They will bear a large circumferential gas load under the impact of the gas. Therefore, it is necessary to ensure that there is a relatively stable and reliable circumferential positioning structure between each section of the guide vane sector and the low-pressure turbine casing, so that the guide vanes can work stably under the impact of the airflow. At the same time, the turbine outer ring and the guide vane are generally sector structures, and each section of the turbine outer ring and the turbine guide vane are also kept relatively still by the positioning structure.

[0004] The traditional positioning structure generally provides an integrally connected protrusion on the turbine outer ring, and provides a groove that matches the protrusion on the low-vortex casing and the low-vortex guide vane, so that the low-vortex outer ring can simultaneously position the low-vortex casing and the guide vane. However, since the protrusion and the turbine outer ring are integrally provided, this structure has a blind assembly process during the assembly process, and the positioning accuracy of the protrusion and the groove on the low-vortex casing and the low-vortex guide vane cannot be determined. In addition, the protrusion structure designed in the middle of the fan-shaped section of the turbine outer ring has poor processing technology. In order to avoid the interference of the protrusion with the chamfered corners of the groove on the low-vortex casing and the low-vortex guide vane, the turbine outer ring generally needs to be cleaned, and the processing efficiency is low. Summary of the invention

[0005] An object of the present invention is to provide a turbine guide vane positioning structure which has better guide vane assembly efficiency while ensuring the circumferential stability of the guide vane.

[0006] To achieve the above-mentioned purpose, a turbine guide vane positioning structure is arranged at the connection between the guide vane hook, the turbine outer ring and the turbine casing, and includes a positioning block, a first groove, a second groove and an axial positioning portion. The first groove is arranged on the guide vane hook; the second groove is arranged on the turbine casing, facing the first groove in the radial direction, and defining a cavity for accommodating at least part of the positioning block; the axial positioning portion is arranged on the turbine outer ring, and is used to fix the positioning block together with the guide vane hook and the turbine outer ring.

[0007] In one or more embodiments, the axial positioning portion is a third groove provided on the turbine outer ring, for engaging at least a portion of the positioning block.

[0008] In one or more embodiments, a pair of chamfers is provided on a side of the positioning block facing the cavity.

[0009] In one or more embodiments, an axially extending protruding claw is further provided on the radial side of the third groove to engage with the positioning block.

[0010] In one or more embodiments, the axial positioning portion includes a circumferential retaining ring, and the circumferential retaining ring is used to axially compress the positioning block.

[0011] In one or more embodiments, the turbine casing further comprises a circumferential groove accommodating the radially outer side of the circumferential retaining ring.

[0012] In one or more embodiments, the positioning block includes an axially extending threaded hole.

[0013] In one or more embodiments, a chamfer is provided on a side of the positioning block facing the circumferential retaining ring.

[0014] In one or more embodiments, the turbine outer ring includes a turbine outer ring hook, the turbine outer ring hook encloses a concave cavity, and the concave cavity is used to accommodate the guide vane hook and a portion of the turbine casing.

[0015] Another object of the present invention is to provide a turbine, comprising stator guide vanes, moving blades, a turbine outer ring and a turbine casing, and also comprising the above-mentioned turbine guide vane positioning structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The above and other features, properties and advantages of the present invention will become more apparent through the following description in conjunction with the accompanying drawings and embodiments, in which:

[0017] Figure 1 is a structural schematic diagram of an embodiment of a turbine guide vane positioning structure;

[0018] Figure 2 is a schematic diagram of an embodiment of a positioning block;

[0019] Figure 3 is a structural schematic diagram of another embodiment of a turbine guide vane positioning structure;

[0020] Figure 4 is a schematic diagram of another embodiment of a positioning block;

[0021] Figure 5 It is a schematic diagram of the guide vane hook;

[0022] Figure 6 This is a schematic diagram of the turbine case hook.

[0023] Symbols and Markings

[0024] 10 Turbine case

[0025] 11 Turbine case hook

[0026] 20 Turbine guide vanes

[0027] 21 Guide vane hook

[0028] 30 Turbine outer ring

[0029] 31 Turbine outer ring hook

[0030] 32 Third groove

[0031] 33 Axially extended claw

[0032] 40 Positioning block

[0033] 41 threaded holes

[0034] 42 First chamfer

[0035] 43 Second chamfer

[0036] 44 Third chamfer

[0037] 50 Turbine blades

[0038] 102 Second groove

[0039] 103 inner groove

[0040] 104 Circumferential groove

[0041] 210 First Groove DETAILED DESCRIPTION

[0042] The present invention is further described below in conjunction with specific embodiments and drawings. More details are elaborated in the following description to facilitate a full understanding of the present invention. However, the present invention can obviously be implemented in a variety of other ways different from the description herein. Those skilled in the art can make similar generalizations and deductions based on actual application situations without violating the connotation of the present invention. Therefore, the protection scope of the present invention should not be limited by the content of this specific embodiment.

[0043] It should be noted that these and other subsequent drawings are only examples and are not drawn to scale, and should not be used to limit the actual scope of protection required by the present invention.

[0044] The traditional positioning structure is generally achieved by providing an integrally connected protrusion on the turbine outer ring and a groove that cooperates with the protrusion on the low-vortex casing and the low-vortex guide vane. This design allows the low-vortex outer ring to simultaneously position the low-vortex casing and the guide vane, but has the following disadvantages: First, there will be assembly interference between the chamfers of the protrusion and the grooves on the low-vortex casing and the low-vortex guide vane. In order to avoid interference with the chamfers, the chamfers need to be manually polished and repaired. This process is called root cleaning and has low processing efficiency. Second, the protrusion structure means that the outer ring parts can only be processed by milling, and milling can only process a single part. The milling stress is large, the tool radius requirements at the root cleaning are high, and the surface roughness is poor.

[0045] The turbine guide vane positioning structure disclosed in the present invention can simplify the assembly process and significantly improve the processing efficiency while ensuring the circumferential stability of the guide vane.

[0046] Figure 1 The connection structure of the turbine guide vane 20, the turbine casing 10 and the turbine outer ring 30 is shown. The turbine guide vane 20 includes a guide vane hook 21, which is matched with the turbine casing hook 11 of the turbine casing 10 in the radial direction at the radial inner end surface of the turbine casing hook 11. The turbine outer ring 30 is also provided with a turbine outer ring hook 31, and the turbine outer ring hook 31 includes a concave cavity, which can accommodate the guide vane hook 21 and the turbine casing hook 11 at the same time. Figure 1 shown.

[0047] exist Figure 1 In the diagram, the left-right direction refers to the "axial" direction, the up-down direction refers to the "radial" direction, and the direction perpendicular to the paper plane refers to the "circumferential" direction. The term "axial" refers to the direction parallel to the engine's rotation axis, "radial" refers to the radial direction of the turbine casing assembly, and "circumferential" refers to the circumferential direction of the turbine casing assembly, that is, the direction around the engine's rotation axis.

[0048] The turbine guide vane positioning structure disclosed in the present disclosure includes a positioning block 40 , a first groove 210 disposed on the guide vane hook 21 , a second groove 102 disposed on the turbine casing 10 , and an axial positioning portion disposed on the turbine outer ring 30 .

[0049] The first groove 210 of the guide vane hook 21 and the second groove 102 on the turbine casing hook 11 face each other in the radial direction, defining a cavity for accommodating at least part of the positioning block 40, as shown in FIG. Figure 1 , Figure 5 and Figure 6 The two grooves are arranged with equal widths for placing positioning blocks 40 of equal widths to achieve circumferential positioning between the turbine guide vane 20 and the turbine casing 10 .

[0050] The axial positioning portion is arranged on the turbine outer ring hook 31 located on the right side of the positioning block 40 , and is used to fix the positioning block 40 together with the guide vane hook 21 and the turbine outer ring hook 31 .

[0051] An example of an axial positioning portion is Figure 1 As shown, it includes a circumferential retaining ring 60 for axially pressing the positioning block 40. Specifically, the circumferential retaining ring 60 is a circumferential annular structure, and the two sides in the axial direction are respectively against the surface of the turbine outer ring 30 and the positioning block 40, and a circumferential groove 104 is provided in the turbine casing 10 to accommodate the radial outer side of the circumferential retaining ring 60, so that the radial outer side of the circumferential retaining ring 60 is stuck in the circumferential groove 104. As a result, the positioning block 40 is fixed in both the radial direction and the axial direction, realizing the circumferential positioning of the turbine outer ring 30, the turbine casing 10 and the guide vane 20.

[0052] To facilitate the assembly of the positioning block 40 , the sum of the radial depths of the first groove 210 of the guide vane hook 21 and the second groove 102 on the turbine casing 10 should be slightly greater than the radial height of the positioning block 40 .

[0053] In order to avoid assembly interference, the edge of the positioning block 40 facing the cavity formed by the first groove 210 and the second groove 102 is also provided with a relatively large chamfer, such as Figure 2 The first chamfer 42 and the second chamfer 43 shown are used to prevent the positioning block 40 from interfering with the turbine guide vane 20 and the turbine casing 10 during assembly.

[0054] In some embodiments, a threaded hole or through hole 41 extending axially is also designed in the middle of the positioning block 40, such as Figure 1 and Figure 2 As shown, it is convenient to introduce and disassemble during the assembly process. This is because the size of the positioning block 40 is very small and it is inconvenient to hold it during assembly, so a small hole is designed in the part to facilitate the clamping or hooking of the hook-type tooling to participate in the assembly or disassembly of the positioning block 40.

[0055] It is understandable that, if a plurality of positioning blocks 40 are provided in the circumferential direction, a plurality of grooves intermittently distributed in the circumferential direction are provided on the turbine casing 10 and the guide vane hook 21 to accommodate the positioning blocks 40 .

[0056] Another embodiment of the axial positioning portion is as follows: Figure 3 As shown, the axial positioning portion is a third groove 32 provided on the turbine outer ring 30, and the third groove 32 is used to engage at least part of the positioning block 40. Figure 4 shown.

[0057] The hook 31 of the turbine outer ring 30 is provided with a third groove 32 of the same circumferential width as the positioning block 40, which accommodates one axial side of the positioning block 40 and ensures that it does not fall off, such as an axially extending protruding claw 33 is provided on the radial outer side of the third groove 32 to engage the positioning block 40. At the same time, the first groove 210 of the guide vane hook 21 and the second groove 102 on the turbine casing 10 accommodate the positioning block 40 on the other axial side, and the three grooves jointly fix the positioning block 40 to achieve the circumferential positioning of the turbine outer ring 30, the turbine casing 10 and the guide vane 20.

[0058] On the basis of the above embodiment, a pair of third chamfers 44 are provided on one side of the positioning block 40 facing the cavity formed by the first groove and the second groove. Figure 4 The chamfering can avoid the influence of traditional edges when the first groove and the second groove are connected with the positioning block 40, improve the guide vane assembly path, and further improve the guide vane assembly efficiency.

[0059] The positioning blocks of the above-mentioned turbine guide vane positioning structure are not limited to the dimensions shown in the accompanying drawings, and the structural form can be changed within a certain space, or the circumferential positioning of the guide vanes and the turbine casing can be realized independently, or the traditional guide vane protrusions can be replaced by cooperating with the turbine outer ring to realize the circumferential fixation of the casing, guide vanes and outer ring.

[0060] On the premise of satisfying the circumferential fixing function of the guide vane, the above structure eliminates the traditional raised structure, and can realize the cutting of the entire outer ring into segments after turning to form parts, which significantly improves the processing efficiency, and has high turning accuracy, low stress, no need for root cleaning, and better surface roughness.

[0061] Therefore, the above structure can optimize the assembly path of the guide vane, improve the processability of the guide vane assembly, and further optimize the processing processability of the low-pressure turbine casing and the low-pressure turbine outer ring that match it, improve the product qualification rate, and reduce the manufacturing cost.

[0062] In combination with the above introduction to the turbine guide vane positioning structure, a turbine can also be understood, which includes a stator guide vane 20, a turbine blade 50, a turbine outer ring 30 and a turbine casing 10, and also includes the above turbine guide vane positioning structure.

[0063] It should be noted that the above content uses words such as "first" and "second" to limit components, which is only for the convenience of distinguishing the corresponding components. If not otherwise stated, the above words have no special meaning and therefore cannot be understood as limiting the scope of protection of this application.

[0064] At the same time, the present application uses specific words to describe the embodiments of the present application. For example, "one embodiment", "an embodiment", and / or "some embodiments" refer to a certain feature, structure or characteristic related to at least one embodiment of the present application. Therefore, it should be emphasized and noted that "one embodiment" or "an embodiment" or "an alternative embodiment" mentioned twice or more in different positions in this specification does not necessarily refer to the same embodiment. In addition, some features, structures or characteristics in one or more embodiments of the present application can be appropriately combined.

[0065] Although the present invention is disclosed as above with preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art may make possible changes and modifications without departing from the spirit and scope of the present invention. Therefore, any modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention shall fall within the protection scope defined by the claims of the present invention.

Claims

1. The turbine guide vane positioning structure is arranged at the connection between the guide vane hook, the turbine outer ring and the turbine casing, and is characterized in that: include: Positioning block; A first groove is provided on the guide vane hook; A second groove is provided on the turbine casing, facing the first groove in a radial direction, and defines a cavity for accommodating at least a portion of the positioning block; as well as The axial positioning portion is arranged on the turbine outer ring and is used to fix the positioning block together with the guide vane hook and the turbine outer ring.

2. The turbine guide vane positioning structure according to claim 1, characterized in that: The axial positioning portion is a third groove arranged on the turbine outer ring, which is used to engage at least a portion of the positioning block.

3. The turbine guide vane positioning structure according to claim 2, characterized in that: A chamfer is provided on one side of the positioning block facing the cavity.

4. The turbine guide vane positioning structure according to claim 2, characterized in that: The radial side of the third groove is also provided with an axially extending protruding claw to engage with the positioning block.

5. The turbine guide vane positioning structure according to claim 1, characterized in that: The axial positioning portion includes a circumferential retaining ring, and the circumferential retaining ring is used for axially pressing the positioning block.

6. The turbine guide vane positioning structure according to claim 5, characterized in that: The turbine casing also includes a circumferential groove that receives the radially outer side of the circumferential retaining ring.

7. The turbine guide vane positioning structure according to claim 5, characterized in that: The positioning block includes an axially extending threaded hole.

8. The turbine guide vane positioning structure according to claim 5, characterized in that: A chamfer is provided on one side of the positioning block facing the cavity.

9. The turbine guide vane positioning structure according to claim 1, characterized in that: The turbine outer ring comprises a turbine outer ring hook, and the turbine outer ring hook forms a concave cavity, and the concave cavity is used to accommodate the guide vane hook and a part of the turbine casing.

10. A turbine, comprising stator guide vanes, moving blades, a turbine outer ring and a turbine casing, characterized in that: It also includes the turbine guide vane positioning structure according to any one of claims 1-9.

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