A plug structure applicable to an observation window of an aeroengine and a disassembly and assembly method thereof

Abstract

A plug structure applicable to the observation window of an aeroengine and its disassembly and assembly method, a plug assembly formed by a plug rod, a plug cover, and a guide rivet; the lower end of the plug rod is a plug head; the plug cover is sleeved on the middle part of the plug rod, and the plug cover can rotate around the axis of the plug rod. A snap ring is arranged between the inner hole surface of the plug cover and the outer cylindrical surface of the plug rod to limit the axial position of the plug cover; the guide rivet passes through a transverse hole in the middle of the plug rod and is located below the plug cover; a guide head is arranged at one end of the guide rivet, and a flared opening is arranged at the other end; the guide rivet is clamped on the transverse hole of the plug rod through the guide head and the flared opening; an external thread is arranged on the outer peripheral surface of the lower section of the plug cover for threaded connection with the outer casing of the low-pressure turbine guide vane. When the plug rod, the plug cover, and the guide rivet are assembled and disassembled, the three are an integral body to achieve rapid disassembly and effectively avoid any one of the components from falling into the internal flow path of the engine to form foreign objects.

Description

Technical Field

[0001] The present invention relates to the technical field of aeroengine turbine structures, and particularly to a plug structure applicable to an observation window of an aeroengine and a disassembly and assembly method thereof. Background Art

[0002] For a traditional turbojet engine, it belongs to a typical single-duct structure. The working parameters of the hot-end components are low, and the requirements of the engine hot-end components can be met based on existing materials. Therefore, on the premise of meeting the overall performance indicators, the weight of the engine is minimized as much as possible and the structure of the engine is simplified. As a result, when the turbojet engine undergoes long-term test runs, problems such as wear, missing blocks, and cracks in the hot-end components rarely occur.

[0003] With the increase in the turbine inlet temperature of aeroengines, the working temperature of the hot-end components exceeds the limit temperature of their materials. Therefore, during the long-term test runs of aeroengines, it is necessary to regularly conduct borescope inspections on their hot-end components to prevent serious problems such as wear, missing blocks, and cracks in the hot-end components. Compared with traditional turbojet engines, an installation seat needs to be provided on the outer casing for borescope inspections during the long-term test runs of the engine. The speed of the borescope inspection depends on the disassembly speed of the observation window plug. At the same time, the disassembly of the observation window plug should not only be convenient and fast, but also no foreign objects (such as the guiding components of the observation window plug, etc.) should fall into the internal flow path of the engine, because if foreign objects fall into the flow path, it means that the subsequent test run safety of the engine cannot be effectively guaranteed, seriously affecting the stable, reliable, and safe operation of the engine.

[0004] The observation window plugs in the prior art cannot be conveniently and quickly removed due to deficiencies in their structural design, and their components are prone to forming foreign objects that easily fall into the internal flow path of the engine during the disassembly process, affecting the operation of the engine. Summary of the Invention

[0005] The main objective of the present invention is to propose a plug structure applicable to an observation window of an aeroengine and a disassembly and assembly method thereof, aiming to solve the above technical problems.

[0006] To achieve the above object, on the one hand, the present invention provides a plug structure applicable to the observation window of an aero-engine, which includes a plug rod, a plug cover, and a plug assembly formed by a guide rivet; the lower end of the plug rod is a plug head; the plug cover is sleeved on the middle part of the plug rod, and the plug cover can rotate around the axis of the plug rod. A snap ring is arranged between the inner hole surface of the plug cover and the outer cylindrical surface of the plug rod to limit the axial position of the plug cover; the guide rivet passes through the transverse hole in the middle of the plug rod and is located below the plug cover; a guide head is arranged at one end of the guide rivet, and a flared opening is arranged at the other end; the guide rivet is clamped on the transverse hole of the plug rod through the guide head and the flared opening; an external thread is arranged on the outer peripheral surface of the lower section of the plug cover for threaded connection with the outer casing of the low-pressure turbine guide vane.

[0007] Preferably, a plurality of concave openings are evenly distributed on the flange plate at the upper part of the plug cover.

[0008] Preferably, the guide head is in the shape of a hemisphere.

[0009] Preferably, a threaded portion is arranged on the upper section of the plug rod.

[0010] Preferably, an outer ring groove is arranged on the outer cylindrical surface in the middle of the plug rod, and an inner ring groove is arranged on the inner hole surface of the plug cover. The outer ring groove and the inner ring groove form an annular groove for accommodating the snap ring.

[0011] Preferably, a side hole is arranged on the plug cover, and the side hole communicates with the inner ring groove of the plug cover; the snap ring is of an open-ring structure; during assembly, the snap ring is unfolded into a straight line from the opening and inserted into the annular groove formed by the outer ring groove and the inner ring groove through the side hole to form a snap ring.

[0012] Preferably, a cutting plane is arranged in the middle of the plug rod, the transverse hole in the middle of the plug rod is perpendicular to the cutting plane, and the guide head abuts against the cutting plane. A flared opening is arranged at one end of the transverse hole in the middle of the plug rod away from the cutting plane, and the outer conical surface of the flared opening on the guide rivet is matched with the flared opening.

[0013] Preferably, the lower end surface of the plug head is an inclined cutting surface, and the inclination angle of the inclined cutting surface is the same as the inclination angle of the inner wall of the hot-end component of the aero-engine.

[0014] On the other hand, the present invention also provides a disassembly and assembly method for the above plug structure applicable to the observation window of an aero-engine, including the following steps:

[0015] Step 1: During the assembly of the plug structure, insert the plug assembly formed by the plug rod, the plug cover, and the guide rivet onto the outer casing of the low-pressure turbine guide vane, so that the guide head of the guide rivet slides downward along the radial groove of the outer casing of the low-pressure turbine guide vane, and press the plug rod downward to insert the plug head into the observation window of the hot-end component, and screw the plug cover onto the outer casing of the low-pressure turbine guide vane through the external thread.

[0016] Step 2: When disassembling the plug structure, loosen the plug cover and pull out the plug structure, and then carry out the engine borescope operation.

[0017] Preferably, in Step 1, after screwing the plug cover onto the outer casing of the low-pressure turbine guide vane through external threads, a bushing and a nut are provided on the threaded part of the upper section of the plug rod, and the nut is screwed to press the bushing downward against the plug cover; the plug cover is fixed to the bushing and the outer casing of the low-pressure turbine guide vane through a J-shaped pin passing through the concave opening; in Step 2, when disassembling the plug structure, first remove the bushing, nut and J-shaped pin, and then loosen the plug cover to pull out the plug structure.

[0018] Due to the adoption of the above technical solution, the beneficial effects of the present invention are as follows:

[0019] Since the plug structure in the present invention is a plug assembly formed by a plug rod, a plug cover and a guide rivet, when the plug rod, the plug cover and the guide rivet are assembled and disassembled, the three are an integral whole, that is, the whole is inserted into the outer casing of the low-pressure turbine guide vane, or the whole is pulled out from the outer casing of the low-pressure turbine guide vane. Using the guide rivet as a guiding component, its guiding head slides and cooperates with the radial groove of the outer casing of the low-pressure turbine guide vane for guiding, so that the plug part of the plug rod can accurately insert into the observation window of the hot end component. Since the plug rod, the plug cover and the guide rivet are an integral assembly structure, it can effectively prevent a certain component from falling into the internal flow path of the engine to form foreign objects during the plugging and unplugging process. Therefore, the observation window plug structure provided by the present invention can avoid the problem of foreign objects falling into the flow path caused by disassembly and assembly. At the same time, with an integral plugging and unplugging structure, the observation window plug can be disassembled quickly without affecting the engine startup node. Description of the Drawings

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on the structures shown in these drawings.

[0021] Figure 1 It is a cross-sectional view of the plug structure provided by the present invention;

[0022] Figure 2 It is a three-dimensional structure diagram of the plug structure provided by the present invention;

[0023] Figure 3 It is a structural diagram of the plug rod in the present invention;

[0024] Figure 4Schematic diagram of the plug structure provided by the present invention when installed on the outer casing of the low-pressure turbine guide vane

[0025] Figure 5 Schematic diagram of the plug cover in the present invention

[0026] Figure 6 Schematic diagram of the guide rivet in the present invention

[0027] Figure 7 Schematic diagram of the snap ring in the present invention

[0028] Explanation of the reference numerals in the drawings: 1. Plug rod; 1-1. Plug head; 1-2. Outer ring groove; 1-3. Cutting plane; 1-4. Flared mouth; 1-5. Tapered section; 2. Plug cover; 2-1. Inner ring groove; 3. Guide rivet; 3-1. Guide head; 4. Screw part; 5. Snap ring; 6. Side hole; 7. Flared opening; 8. Concave opening; 9. External thread; 10. Outer casing of the low-pressure turbine guide vane; 10-1. Radial groove; 11. Hot end component; 12. J-type pin; 13. Bushing; 14. Nut. Detailed implementation manners

[0029] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0030] It should be noted that all the directional indications (such as up, down, left, right, front, back...) in the embodiments of the present invention are only used to explain the relative positional relationship and movement conditions between components in a specific posture (as shown in the drawings). If the specific posture changes, the directional indications will also change accordingly.

[0031] Combined with Figures 1 to 4 and Figure 6 As shown, a plug structure applicable to the observation window of an aeroengine includes a plug assembly formed by a plug rod 1, a plug cover 2, and a guide rivet 3; the lower end of the plug rod 1 is a plug head 1-1, and the plug head 1-1 is used to be inserted into the observation of the hot end component 11 and block it; the plug cover 2 is sleeved on the middle of the plug rod 1, and the plug cover 2 can rotate around the axis of the plug rod 1. A snap ring 5 is arranged between the inner hole surface of the plug cover 2 and the outer cylindrical surface of the plug rod 1 to limit the axial position of the plug cover 2.

[0032] The guiding rivet 3 passes through the transverse hole in the middle of the plug rod 1 and is located below the plug cover 2; a guiding head 3-1 is provided at one end of the guiding rivet 3, and a flared opening 7 is provided at the other end; the guiding rivet 3 is clamped on the transverse hole of the plug rod 1 through the guiding head 3-1 and the flared opening 7; the guiding head 3-1 is used for sliding cooperation with the radial groove 10-1 of the outer casing 10 of the low-pressure turbine guide vane for guiding.

[0033] An external thread 9 is provided on the outer peripheral surface of the lower section of the plug cover 2 for threaded connection with the outer casing 10 of the low-pressure turbine guide vane.

[0034] Combined Figure 4 As shown, in this embodiment, a plurality of concave openings 8 are evenly distributed on the flange plate of the upper part of the plug cover 2. When the plug assembly is installed on the outer casing 10 of the low-pressure turbine guide vane, after the plug cover 2 is tightened, the J-shaped pin 12 is used to fix with the outer casing 10 of the low-pressure turbine guide vane through the concave openings 8.

[0035] Combined Figure 6 As shown, the guiding head 3-1 is hemispherical in shape. By using the hemispherical shape, the spherical surface slides in cooperation with the radial groove 10-1 of the outer casing 10 of the low-pressure turbine guide vane.

[0036] Combined Figure 4 As shown, a threaded portion 4 is provided on the upper section of the plug rod 1. When the plug assembly is assembled, in order to ensure the firm connection between the plug assembly and the outer casing 10 of the low-pressure turbine guide vane, a bushing 13 and a nut 14 are provided on the threaded portion 4 of the upper section of the plug rod 1, and the nut 14 is screwed so that the bushing 13 presses the plug cover 2 downward; the plug cover 2 is fixed with the bushing 13 and the outer casing 10 of the low-pressure turbine guide vane by using the J-shaped pin 12 through the concave openings 8.

[0037] Combined Figure 1 As shown, an outer ring groove 1-2 is provided on the outer cylindrical surface in the middle of the plug rod 1, and an inner ring groove 2-1 is provided on the inner hole surface of the plug cover 2. The outer ring groove 1-2 and the inner ring groove 2-1 form an annular groove for accommodating the snap ring 5. The structure of the snap ring 5, the inner ring groove 2-1, and the outer ring groove 1-2 can limit the plug cover 2 and restrict its axial position on the plug rod 1. At the same time, it can also make the plug cover 2 rotate around the plug rod 1.

[0038] Combined Figure 1 And Figure 7 As shown, a side hole 6 is provided on the plug cover 2, and the side hole 6 communicates with the inner ring groove 2-1 of the plug cover 2; the snap ring 5 is of an open-ring structure, and the material of the snap ring 5 is a steel wire with a certain elasticity; during assembly, the snap ring 5 is unfolded into a straight line from the opening and inserted into the annular groove formed by the outer ring groove 1-2 and the inner ring groove 2-1 through the side hole 6 to form a snap ring 5.

[0039] CombinedFigure 2 , Figure 3 As shown in Figure 3 , a cutting plane 1-3 is provided in the middle of the plug rod 1. The transverse hole in the middle of the plug rod 1 is perpendicular to this cutting plane 1-3, and the guiding head 3-1 abuts against this cutting plane 1-3. A flared opening 1-4 is provided at one end of the transverse hole in the middle of the plug rod 1 away from the cutting plane 1-3, and the outer conical surface of the flared opening 7 on the guiding rivet 3 is matched with the flared opening 1-4. The cutting plane 1-3 is provided to facilitate the formation of a planar contact between the hemispherical guiding head 3-1 and the cutting plane 1-3, increasing the contact area. The flared opening 1-4 can not only form an accommodating space for the flared opening 7, but also be matched with the outer conical surface of the flared opening 7 to limit the guiding rivet 3.

[0040] Combined Figure 4 As shown in Figure 4 , the lower end surface of the plug head portion 1-1 is an inclined cutting surface 1-5, and the inclination angle of this inclined cutting surface 1-5 is the same as the inclination angle of the inner wall of the hot end component 11 of the aero-engine. The inclined cutting surface 1-5 is provided to prevent the end surface of the plug head portion 1-1 from interfering with other parts inside the hot end component 11.

[0041] On the other hand, the present invention also provides a disassembly and assembly method for the above plug structure applicable to the observation window of an aero-engine, including the following steps:

[0042] Step 1: When assembling the plug structure, insert the plug assembly formed by the plug rod 1, the plug cover 2, and the guiding rivet 3 into the outer casing 10 of the low-pressure turbine guide vane, so that the guiding head 3-1 of the guiding rivet 3 slides downward along the radial groove 10-1 of the outer casing 10 of the low-pressure turbine guide vane, and press the plug rod 1 downward to insert the plug head portion 1-1 into the observation window of the hot end component 11, and then screw the plug cover 2 onto the outer casing 10 of the low-pressure turbine guide vane through the external thread 9;

[0043] Step 2: When disassembling the plug structure, unscrew the plug cover 2 and pull out the plug structure, and then carry out the engine borescope inspection operation.

[0044] Further, in Step 1, after screwing the plug cover 2 onto the outer casing 10 of the low-pressure turbine guide vane through the external thread 9, fix it with the J-shaped pin 12 through the concave opening 8 and the outer casing 10 of the low-pressure turbine guide vane. At the same time, arrange a bushing 13 and a nut 14 on the threaded portion 4 of the upper section of the plug rod 1, and screw the nut 14 to press the bushing 13 downward to press the plug cover 2; in Step 2, when disassembling the plug structure, first remove the bushing 13, the nut 14, and the J-shaped pin 12, and then unscrew the plug cover 2 to pull out the plug structure.

[0045] The above are only the preferred embodiments of the present invention, and do not limit the patent scope of the present invention accordingly. Any equivalent structural transformation made under the inventive concept of the present invention by using the content of the specification and drawings of the present invention, or any direct / indirect application in other related technical fields is included in the patent protection scope of the present invention.

Claims

1. A plug structure applicable to the observation window of an aeroengine, characterized in that, A plug head assembly formed by a plug head rod (1), a plug cover (2), and a guide rivet (3); The lower end of the plug head rod (1) is a plug head portion (1-1); The plug cover (2) is sleeved on the middle part of the plug head rod (1), and the plug cover (2) can rotate around the axis of the plug head rod (1). A snap ring (5) is arranged between the inner hole surface of the plug cover (2) and the outer cylindrical surface of the plug head rod (1) to limit the axial position of the plug cover (2); The guide rivet (3) is transversely arranged on the transverse hole in the middle of the plug head rod (1) and is located below the plug cover (2); a guide head (3-1) is arranged at one end of the guide rivet (3), and a flared opening (7) is arranged at the other end; the guide rivet (3) is clamped on the transverse hole of the plug head rod (1) through the guide head (3-1) and the flared opening (7); An external thread (9) is arranged on the outer peripheral surface of the lower section of the plug cover (2) for threaded connection with the outer casing of the low-pressure turbine guide vane (10); A plurality of concave openings (8) are evenly distributed on the flange plate of the upper part of the plug cover (2); A threaded portion (4) is arranged on the upper section of the plug head rod (1); The lower end surface of the plug head portion (1-1) is an inclined cutting surface (1-5), and the inclination angle of the inclined cutting surface (1-5) is the same as the inclination angle of the inner wall of the hot end component (11) of the aero-engine; The guide head (3-1) is slidably matched with the radial groove of the outer casing of the low-pressure turbine guide vane for guiding, so that the plug head portion (1-1) of the plug head rod (1) can accurately insert into the observation window of the hot end component (11) of the aero-engine; A bushing (13) and a nut (14) are arranged on the threaded portion (4) of the upper section of the plug head rod (1). The nut (14) is screwed to press the bushing (13) downward against the plug cover (2); the plug cover (2) is fixed to the bushing (13) and the outer casing of the low-pressure turbine guide vane (10) by using a J-shaped pin (12) through the concave opening (8); 2. The plug structure applicable to the observation window of an aeroengine according to claim 1, wherein The guide head (3-1) is in the shape of a hemisphere; 3. The plug structure applicable to the observation window of an aeroengine according to claim 1, wherein, An outer ring groove (1-2) is arranged on the outer cylindrical surface in the middle of the plug head rod (1), and an inner ring groove (2-1) is arranged on the inner hole surface of the plug cover (2). The outer ring groove (1-2) and the inner ring groove (2-1) form an annular groove for accommodating the snap ring (5); 4. The plug structure applicable to the observation window of an aero-engine according to claim 3, wherein, A side hole (6) is arranged on the plug cover (2), and the side hole (6) communicates with the inner ring groove (2-1) of the plug cover (2); the snap ring (5) is of an open ring structure; during assembly, the snap ring (5) is unfolded into a straight line from the opening and inserted into the annular groove formed by the outer ring groove (1-2) and the inner ring groove (2-1) through the side hole (6) to form a snap ring (5) by surrounding; 5. The plug structure applicable to the observation window of an aeroengine according to claim 1, characterized in that, A cutting plane (1-3) is arranged in the middle of the plug head rod (1). The transverse hole in the middle of the plug head rod (1) is perpendicular to the cutting plane (1-3), and the guide head (3-1) abuts against the cutting plane (1-3). A flared opening (1-4) is arranged at the end of the transverse hole in the middle of the plug head rod (1) far from the cutting plane (1-3). The outer conical surface of the flared opening (7) on the guide rivet (3) is matched with the flared opening (1-4); 6. A disassembly and assembly method for a plug structure applicable to an observation window of an aeroengine, as described in any one of claims 1 to 5, characterized in that, Including the following steps: Step 1: When assembling the plug structure, insert the plug assembly formed by the plug rod (1), the plug cover (2), and the guide rivet (3) onto the outer casing (10) of the low-pressure turbine guide vane, so that the guide head (3-1) of the guide rivet (3) slides downward along the radial groove (10-1) of the outer casing (10) of the low-pressure turbine guide vane, and presses the plug rod (1) downward, so that the plug head (1-1) is inserted into the observation window of the hot-end component (11), and then screw the plug cover (2) onto the outer casing (10) of the low-pressure turbine guide vane through the external thread (9); Step 2: When disassembling the plug structure, loosen the plug cover (2), pull out the plug structure, and then carry out the engine borescope inspection operation.

7. The disassembly and assembly method of the plug structure applicable to the observation window of an aeroengine, characterized in that, In Step 1, after screwing the plug cover (2) onto the outer casing (10) of the low-pressure turbine guide vane through the external thread (9), simultaneously set a bushing (13) and a nut (14) on the threaded part (4) of the upper section of the plug rod (1), and screw the nut (14) to press the bushing (13) downward against the plug cover (2), and the plug cover (2) is fixed to the bushing (13) and the outer casing (10) of the low-pressure turbine guide vane through the J-shaped pin (12) via the concave opening (8); In Step 2, when disassembling the plug structure, first remove the bushing (13), the nut (14), and the J-shaped pin (12), and then loosen the plug cover (2), and the plug structure can be pulled out.

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