A high-pressure turbine outer ring connecting positioning structure capable of adjusting a blade tip gap

Abstract

The application provides a high-pressure turbine outer ring connecting positioning structure for adjusting blade tip clearance, and belongs to the field of aero-engines. The structure comprises: a turbine casing; an outer ring fixing ring fixed on the turbine casing; a high-pressure turbine outer ring installed on the outer ring fixing ring through connecting pins; and connecting pins of multiple specifications, which have pin heads with circumferential positioning surfaces, large-diameter fitting sections and small-diameter fitting sections. The circumferential positioning surfaces are matched with planes or circular arc surfaces on the outer ring fixing ring to realize circumferential positioning. The large-diameter fitting sections are matched with mounting holes on the outer ring fixing ring, and the small-diameter fitting sections are matched with pin holes on the high-pressure turbine outer ring. The connecting pins comprise non-eccentric structures and eccentric structures with small-diameter fitting sections eccentric downward or upward to different degrees. When the high-pressure turbine outer ring is assembled on the outer ring fixing ring, connecting pins with different eccentric amounts are selected according to requirements to realize adjustment of the radial height of the high-pressure turbine outer ring, so that the blade tip clearance between blades and the high-pressure turbine outer ring is adjusted.

Description

Technical Field

[0001] This application belongs to the field of aero-engines, and specifically relates to a high-pressure turbine outer ring connection and positioning structure that can be used to adjust blade tip clearance. Background Technology

[0002] The blade tip clearance (i.e., the radial clearance between the turbine rotor blade tip and the stator flow channel) of high-pressure turbines and gas turbines is a key factor affecting turbine aerodynamic performance. To achieve optimal high-pressure turbine performance while avoiding severe rubbing between the blade tip and the stator flow channel, the blade tip assembly clearance is usually adjusted multiple times during the high-pressure turbine development process to find an optimal clearance value.

[0003] To adjust the tip clearance of a high-pressure turbine blade, the blade tip height or the radial height of the stator flow channel surface (commonly referred to as the "high-pressure turbine outer ring") needs to be adjusted. Currently, each clearance adjustment requires reprocessing the component at the factory or replacing it with a new one. Reducing the clearance can only be achieved by replacing the component. Therefore, each newly developed engine requires ordering one or more expensive sets of rotor blades or high-pressure turbine outer rings as spares, increasing development costs. Summary of the Invention

[0004] The purpose of this application is to provide a high-pressure turbine outer ring connection positioning structure that can be used to adjust the blade tip clearance, so as to solve or alleviate at least one of the problems in the prior art.

[0005] The technical solution of this application is: a high-pressure turbine outer ring connection and positioning structure that can be used to adjust the blade tip clearance, comprising:

[0006] Turbine casing;

[0007] An outer ring retaining ring is fixed to the turbine casing;

[0008] A high-pressure turbine outer ring, wherein the high-pressure turbine outer ring is mounted to the outer ring fixing ring by a connecting pin; and

[0009] Various specifications of connecting pins are provided. Each connecting pin has a pin head with a circumferential positioning surface, a large-diameter mating section, and a small-diameter mating section. The circumferential positioning surface mates with a plane or arc surface on the outer ring fixing ring to achieve circumferential positioning. The large-diameter mating section mates with a mounting hole on the outer ring fixing ring, and the small-diameter mating section mates with a pin hole on the outer ring of the high-pressure turbine. The connecting pin includes a non-eccentric structure with the small-diameter mating section and the large-diameter mating section coaxial with each other, and an eccentric structure with the small-diameter mating section relative to the large-diameter mating section downward or upward along the normal of the circumferential positioning surface to different degrees.

[0010] When assembling the high-pressure turbine outer ring onto the outer ring fixing ring, connecting pins with different eccentricities can be selected as needed to adjust the radial height of the high-pressure turbine outer ring, thereby achieving the adjustment of the blade tip clearance between the blade and the high-pressure turbine outer ring.

[0011] In at least one embodiment of this application, the outer ring fixing ring is a fan-shaped segment structure, and the outer ring fixing ring has two mounting sides arranged forward and backward along the airflow. Multiple outer ring fixing rings are spliced ​​together to form a complete ring structure and fixed to the turbine casing.

[0012] In at least one embodiment of this application, the outer ring fixing ring is limited by a front baffle, and the front baffle is fixed to the turbine casing by a locking pin.

[0013] In at least one embodiment of this application, the high-pressure turbine outer ring is a fan-shaped segment structure, the high-pressure turbine outer ring has an mounting edge that adapts to the outer ring fixing ring, and the two circumferential ends of the mounting edge are provided with a first pin hole and a second pin hole, and the high-pressure turbine outer ring is mounted on the outer ring fixing ring by connecting pins passing through the first pin hole and the second pin hole.

[0014] In at least one embodiment of this application, the first pin hole is a round hole, and the second pin hole is an elongated hole with a longer circumferential distance.

[0015] In at least one embodiment of this application, the circumferential length of the outer ring fixing ring is N times the circumferential length of the high-pressure turbine outer ring, so that a single outer ring fixing ring can install N high-pressure turbine outer rings, where N is a natural number.

[0016] In at least one embodiment of this application, the outer ring fixing ring and / or the high-pressure turbine ring are provided with a sealing groove on their circumferential side, and the sealing groove is used to install a sealing plate.

[0017] In at least one embodiment of this application, an orifice plate is also included. The orifice plate is disposed between the high-pressure turbine outer ring and the outer ring fixing ring. Cooling gas flowing into the inner side of the outer ring fixing ring from the cooling channel disposed inside the outer ring fixing ring passes through the cooling holes disposed on the orifice plate to perform impact cooling on the high-pressure turbine outer ring.

[0018] In at least one embodiment of this application, the degree or amount of eccentricity of the minor diameter mating section does not exceed the projection range of the major diameter mating section in the direction of the centerline of the minor diameter mating section.

[0019] The high-pressure turbine outer ring connection and positioning structure provided in this application can realize the adjustment of the radial height of the high-pressure turbine outer ring and the adjustment of the blade tip clearance of the high-pressure turbine. Compared with the prior art, which requires re-machining or reassembly for each blade tip clearance adjustment, this application can achieve the same result by replacing the connecting pin with a suitable eccentricity and installing the high-pressure turbine outer ring. It eliminates the need to customize spare parts for clearance adjustment and avoids the process of returning to the factory for re-machining. The development cost is low, the efficiency is high, and the cycle is short. Attached Figure Description

[0020] To more clearly illustrate the technical solutions provided in this application, the accompanying drawings will be briefly described below. Obviously, the drawings described below are merely some embodiments of this application.

[0021] Figure 1 This is a schematic diagram of the overall positioning structure for the high-pressure turbine outer ring connection in this application.

[0022] Figure 2 This is a schematic diagram of the high-pressure turbine outer ring structure of this application.

[0023] Figure 3 This is a schematic diagram of different types of connecting pins in this application.

[0024] Figure label:

[0025] 1-Turbine casing; 11-Front retaining ring; 12-Locking pin;

[0026] 2-Outer ring fixing ring,

[0027] 3-High-pressure turbine ring, 31-Mounting edge, 32-First pin hole, 33-Second pin hole, 34-Sealing groove;

[0028] 4-blade;

[0029] 5-Connecting pin, 51-Major diameter mating section, 52-Minor diameter mating section, 53-Circumferential positioning surface, 54-Pin head;

[0030] 61-Clamping ring, 62-Clamping plate;

[0031] 7-hole plate;

[0032] 8- Corrugated sealing ring. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below with reference to the accompanying drawings.

[0034] To overcome the problems of high cost, low efficiency, and long cycle caused by the lack of tip clearance adjustment function in the traditional high-pressure turbine outer ring connection structure, which prevents the verification of multiple tip clearances during the development stage, this application provides a high-pressure turbine outer ring connection positioning structure that can be used to adjust tip clearance.

[0035] like Figures 1 to 3 As shown, the high-pressure turbine outer ring connection and positioning structure provided in this application for adjusting blade tip clearance includes: turbine casing 1, outer ring fixing ring 2, high-pressure turbine outer ring 3, and connecting pin 5.

[0036] The outer ring fixing ring 2 is installed on the turbine casing 1 by insertion. After the front retaining ring 11 axially limits the inserted outer ring fixing ring 2, the front retaining ring 11 is fixed on the turbine casing 11 by locking pin 12, thereby realizing the fixation of the outer ring fixing ring 2.

[0037] Combination Figure 2 As shown, the main body of the high-pressure turbine outer ring 3 is a fan-shaped segment structure, and multiple fan-shaped segments can be spliced ​​together circumferentially to form a complete ring structure. This fan-shaped segment structure has two radially extending mounting edges 31 (front and rear, in the direction of airflow). A first pin hole 32 and a second pin hole 33 are respectively provided at the circumferential ends of the front and rear mounting edges 31 of the high-pressure turbine outer ring 3. The first pin hole 32 is a circular hole, and the second pin hole 33 is a longer hole with a slightly longer circumferential distance. The first pin hole 32 and the second pin hole 33 are located on the same side of the front and rear mounting edges 31. By configuring the first pin hole 32 and the second pin hole 33 as a circular hole and a longer hole, respectively, when the high-pressure turbine outer ring 3 is installed on the outer ring fixing ring 2, the radial positioning of the high-pressure turbine outer ring 2 can be ensured while achieving coordinated circumferential thermal deformation.

[0038] Similar to the structure of the high-pressure turbine outer ring 3, the outer ring fixing ring 2 also has a fan-shaped segment structure. The circumferential length of the outer ring fixing ring 2 is typically greater than that of the high-pressure turbine outer ring 3, being several times larger. For example, the circumferential length of the outer ring fixing ring 2 can be 2 to 4 times the circumferential length of the high-pressure turbine outer ring 3, thus allowing approximately 2 to 4 high-pressure turbine outer rings 3 to be installed on each outer ring fixing ring 2.

[0039] The outer ring fixing ring 2 also has front and rear mounting edges, with mounting holes on these edges corresponding to the first pin hole 32 and the second pin hole 33 of the high-pressure turbine outer ring 3. Multiple fan-shaped segment outer ring fixing rings 2 are spliced ​​together to form a complete ring structure and then installed on the turbine casing 1. The front and rear mounting edges 31 of each high-pressure turbine outer ring 3 are respectively mounted and positioned onto the front and rear mounting edges of the outer ring fixing ring 2 using two connecting pins 5. The front and rear connecting pins 5 are respectively limited to the outer ring fixing ring 2 by retaining rings 61 or locking pieces 62, thereby achieving the connection between the high-pressure turbine outer ring 3 and the turbine casing 1. A corrugated sealing ring 8 can be provided between the mounting edge 31 on the front side of the high-pressure turbine outer ring 3 and the outer ring fixing ring 2 to achieve a seal.

[0040] In some embodiments of this application, to enhance the impact cooling effect on the high-pressure turbine outer ring 3, a cooling channel communicating with lower-temperature gas is provided inside the outer ring fixing ring 2. Simultaneously, an orifice plate 7 is provided between the outer ring fixing ring 2 and the high-pressure turbine outer ring 3. The orifice plate 7 has multiple cooling holes facing the high-pressure turbine outer ring 7. Cooling gas flowing in from the cooling channel of the outer ring fixing ring 2 can pass through the cooling holes of the orifice plate 7 and impact the surface of the high-pressure turbine outer ring 3. In some embodiments of this application, the orifice plate 7 can be installed on the inner or lower side of the outer ring fixing ring 2 by welding.

[0041] To ensure axial sealing and deformation coordination between the high-pressure turbine outer ring 3 and the outer ring fixed ring 2, a sealing ring in the form of a whole ring is provided between the high-pressure turbine outer ring 3 and the outer ring fixed ring 2.

[0042] In some embodiments of this application, sealing grooves 34 can be provided on both circumferential sides of the high-pressure turbine outer ring 3 and the outer ring fixing ring 2 for installing sealing plates.

[0043] like Figure 3 The diagram shows different types of connecting pin structures in this application. The connecting pin 5 includes a pin head 54, a large-diameter mating section 51, and a small-diameter mating section 52. The pin head 54 is provided with a circumferential positioning surface 53, which mates with the plane or arc surface on the outer ring fixing ring 2 to achieve circumferential positioning. The large-diameter mating section 51 mates with the mounting hole on the outer ring fixing ring 2, and the small-diameter mating section 52 mates with the pin hole on the high-pressure turbine outer ring 3.

[0044] The connecting pins 5 come in various specifications and types, including a non-eccentric structure (i.e., the large-diameter mating section 51 and the small-diameter mating section 52 are coaxial) and an eccentric structure with the small-diameter mating section 52 being eccentric to varying degrees relative to the large-diameter mating section 51, either downwards or upwards, along the normal direction of the circumferential positioning surface 53. When assembling the high-pressure turbine outer ring 3 onto the outer ring fixing ring 2, different eccentric connecting pins 5 can be selected as needed to adjust the radial height of the high-pressure turbine outer ring 3, thereby achieving the adjustment target of the blade tip clearance between the blade 4 and the high-pressure turbine outer ring 3.

[0045] like Figure 3 The figures shown are schematic diagrams of different types of connecting pins in this application. Figure a shows a connecting pin without an eccentric structure, Figure b shows a structure in which the small diameter mating section 52 is eccentric downward relative to the large diameter mating section 51, and Figure c shows a structure in which the small diameter mating section 52 is eccentric upward relative to the large diameter mating section 51.

[0046] To ensure the assemblability of the connecting pin 5, the degree or amount of eccentricity of the minor diameter mating section 52 shall not exceed the projection range of the major diameter mating section 51 in the direction of its centerline. For example, if the diameter of the major diameter mating section 51 is 5mm and the diameter of the minor diameter mating section 52 is 4mm, then the minor diameter mating section 52 is allowed to be eccentric relative to the major diameter mating section 51 within a range of 0.5mm downwards or upwards, in order to ensure that the minor diameter mating section 52 has a complete outer circular mating surface.

[0047] The assembly process of the high-pressure turbine outer ring connection and positioning structure in this application is as follows:

[0048] S1. Before installing the high-pressure turbine outer ring 3, the fan-shaped segment structure outer ring fixing ring 2 is spliced ​​and installed piece by piece onto the turbine casing 1 of the whole ring structure. During the installation process, the adjacent outer ring fixing rings 2 are sealed by installing sealing plates. The sealing ring of the whole ring is embedded in the ring cavity of the outer ring fixing ring 2. After all the outer ring fixing rings 2 are installed, the axially limiting front stop ring 11 and locking pin 12 are installed at the front end of the outer ring fixing ring 2.

[0049] S2, after the installation of the outer ring fixing ring 2 is completed, the high pressure turbine outer ring 3 is pushed into the outer ring fixing ring 2 one by one from the radial direction. At the same time, sealing plates are installed between the high pressure turbine outer rings 3. As needed, connecting pins 5 with appropriate eccentricity are selected and installed to install the front and rear mounting edges 31 of the high pressure turbine outer ring 3. The connecting pins 5 are limited to the outer ring fixing ring 2 by the retaining ring 61 or locking plate 62.

[0050] The high-pressure turbine outer ring connection and positioning structure provided in this application installs the high-pressure turbine outer ring 3 onto the outer ring fixing ring 2 by selecting connecting pins with different offsets. This allows for adjustment of the radial height of the high-pressure turbine outer ring 3, thereby adjusting the blade tip clearance of the high-pressure turbine. Compared to the prior art, where each blade tip clearance adjustment requires re-machining or reassembly, this application can achieve this by replacing the connecting pins with appropriate eccentricity to install the high-pressure turbine outer ring. This eliminates the need for custom-made spare parts for clearance adjustment and avoids the process of returning to the factory for re-machining. The development cost is low, the efficiency is high, and the cycle is short.

[0051] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A high-pressure turbine outer ring connection and positioning structure for adjusting blade tip clearance, characterized in that, include: Turbine casing; An outer ring retaining ring is fixed to the turbine casing; A high-pressure turbine outer ring, which is mounted to the outer ring fixing ring by a connecting pin; as well as Various specifications of connecting pins are provided. Each connecting pin has a pin head with a circumferential positioning surface, a large-diameter mating section, and a small-diameter mating section. The circumferential positioning surface mates with a plane or arc surface on the outer ring fixing ring to achieve circumferential positioning. The large-diameter mating section mates with a mounting hole on the outer ring fixing ring, and the small-diameter mating section mates with a pin hole on the outer ring of the high-pressure turbine. The connecting pin includes a non-eccentric structure with the small-diameter mating section and the large-diameter mating section coaxial with each other, and an eccentric structure with the small-diameter mating section relative to the large-diameter mating section downward or upward along the normal of the circumferential positioning surface to different degrees. When assembling the high-pressure turbine outer ring onto the outer ring fixing ring, connecting pins with different eccentricities can be selected as needed to adjust the radial height of the high-pressure turbine outer ring, thereby achieving the adjustment of the blade tip clearance between the blade and the high-pressure turbine outer ring.

2. The high-pressure turbine outer ring connection and positioning structure as described in claim 1, characterized in that, The outer ring fixing ring is a fan-shaped segment structure. The outer ring fixing ring has two mounting sides arranged forward and backward along the airflow. Multiple outer ring fixing rings are spliced ​​together to form a complete ring structure and fixed to the turbine casing.

3. The high-pressure turbine outer ring connection and positioning structure as described in claim 2, characterized in that, The outer ring fixing ring is limited by the front baffle, which is fixed to the turbine casing by locking pins.

4. The high-pressure turbine outer ring connection and positioning structure as described in claim 2, characterized in that, The high-pressure turbine outer ring has a fan-shaped segment structure and an installation edge that is adapted to the outer ring fixing ring. The two circumferential ends of the installation edge are provided with a first pin hole and a second pin hole. The high-pressure turbine outer ring is installed on the outer ring fixing ring by connecting pins passing through the first pin hole and the second pin hole.

5. The high-pressure turbine outer ring connection and positioning structure as described in claim 4, characterized in that, The first pin hole is a round hole, and the second pin hole is a long hole with a longer circumferential distance.

6. The high-pressure turbine outer ring connection and positioning structure as described in claim 5, characterized in that, The circumferential length of the outer ring fixing ring is N times the circumferential length of the high-pressure turbine outer ring, so that a single outer ring fixing ring can install N high-pressure turbine outer rings, where N is a natural number.

7. The high-pressure turbine outer ring connection and positioning structure as described in claim 6, characterized in that, The outer ring fixing ring and / or the high-pressure turbine ring are provided with sealing grooves on their circumferential sides, and sealing plates are installed in the sealing grooves.

8. The high-pressure turbine outer ring connection and positioning structure as described in any one of claims 1 to 7, characterized in that, It also includes an orifice plate, which is set between the outer ring of the high-pressure turbine and the outer ring fixing ring. Cooling gas flowing into the inner side of the outer ring fixing ring from the cooling channel set inside the outer ring fixing ring passes through the cooling holes set on the orifice plate to impact and cool the outer ring of the high-pressure turbine.

9. The high-pressure turbine outer ring connection and positioning structure as described in claim 1, characterized in that, The degree or amount of eccentricity of the minor diameter mating section does not exceed the projection range of the major diameter mating section in the direction of the centerline of the minor diameter mating section.

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