A high-bypass-ratio engine core centering device

Abstract

The application belongs to the field of core engine installation design and relates to a large-bypass-ratio engine core centering device which comprises a rotor connecting mechanism and a stator connecting mechanism, the rotor connecting mechanism comprises a centering bushing, a limiting bolt, a sector body and a torque screw, the stator connecting mechanism comprises a front limiting nut, a rear limiting nut and a flat key, adjustable positioning is realized through the double-thread structure of the limiting bolt, axial positioning and adjustment requirements are realized through the axial compression of the torque screw, the front limiting nut and the rear limiting nut, the radial positioning and supporting structure are separated, the cylindrical surface of the grid tooth part and the stator casing installation edge bolt are utilized to realize the radial positioning of the rotor and the stator, meanwhile, the torque screw matched with the rear internal thread of the shaft is adopted to avoid damage caused by the excessive pressure of the grid tooth part, the contact end face after the tightening of the torque screw prevents the inclination caused by the sinking of the rear end of the rotor, and the axial, radial relative positioning between the rotor and the stator and the angular and axial position adjustment function are realized.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of core engine installation design, and particularly relates to a large-bypass-ratio engine core centering device. BACKGROUND

[0002] The diameter of a certain large-bypass-ratio intermediate nacelle is 1800mm, the front shaft nut of the compressor is embedded and installed on the central transmission driving gear of the intermediate nacelle and cannot be disassembled, the engine is designed as a unit body structure, the whole installation / disassembly of the main unit body can be realized on the structure, the fan main unit body has been assembled before the core engine is installed, and the core engine main unit body needs to be installed from the rear of the intermediate nacelle. Due to the large diameter of the intermediate nacelle, the traditional vertical assembly scheme relying on a turnover vehicle for multiple whole machine turnover has been unable to meet the assembly requirements of the large-bypass-ratio engine because of low installation, high height requirement of the assembly workshop, low operation efficiency of the radial span, high design difficulty and processing cost of the turnover vehicle, and the like. The whole machine needs to be assembled horizontally, that is, the core engine needs to be installed to the fan main unit body in a horizontal posture. Since the positioning connection structure between the rotor and the stator of the core engine has not been installed, a special centering device needs to be designed. As shown in Figure 1 After the core engine is positioned by the centering device, the horizontal installation is performed by cooperating with the centering guide shaft at the front end of the wrench.

[0003] The small-bypass-ratio engine in China adopts a large turnover vehicle to vertically install the intermediate nacelle (with a diameter of about 900mm), sequentially install the high-pressure compressor rotor, the combustion chamber, and the high-pressure turbine, install the centering nacelle after the high-pressure turbine, turn over 90 degrees to the horizontal to limit the force of the shaft front nut, turn over to the vertical state to install the air duct and the No. 4 outer ring, and complete the assembly of the core engine; turn over 180 degrees to install the fan, and then turn over 180 degrees to install the low-pressure turbine and the rear nacelle.

[0004] During the horizontal parking and installation of the core engine of the large-bypass-ratio engine, since the three-point bearing at the front end of the core engine has not been installed, the centering device needs to realize the axial, radial relative positioning between the rotor and the stator, and the angular relative position adjustment to make the outer spline at the front end of the rotor cooperate with the inner spline of the driving bevel gear. In addition, the axial positioning should adapt to the different position requirements of the relative position between the rotor and the stator in different installation stages: the relative position between the rotor and the stator is ensured during the core engine assembly process, and the rotor is ensured to be contacted first during the installation process.

[0005] The core engine of the small-bypass-ratio engine has no horizontal installation process, and only needs to be turned over to the horizontal during the limiting of the shaft front nut during the assembly process. Since the three-point ball bearing has been installed on the core engine to realize the axial positioning function at this time, the centering of the core engine during the assembly process of the small-bypass-ratio engine only needs to realize the radial positioning of the rotor and the stator, and cannot realize the axial, angular and other positioning and adjustment requirements. Figure 2As shown, the outer mounting edge of the centering box is connected with the combustion chamber box, and the inner ring is provided with a process bearing matched with the outer ring of the engine No. 4 to realize the radial positioning of the rotor-stator, and the rotor-stator can rotate relatively.

[0006] Therefore, how to simultaneously realize the axial and radial installation precision of the small and large bypass ratio is a problem to be solved. SUMMARY

[0007] The purpose of the present application is to provide a large bypass ratio engine core centering device to solve the problem that the relative position of the rotor-stator cannot be effectively guaranteed in the prior art for large and small bypass ratio engines.

[0008] The technical scheme of the present application is: a large bypass ratio engine core centering device, comprising a rotor connecting mechanism and a stator connecting mechanism, the rotor connecting mechanism comprising a centering bushing, a limiting bolt, a sector body and a torque screw; the centering bushing is matched with the cylindrical surface of the high-pressure turbine rear shaft grate structure for centering, the limiting bolt is a double-headed thread, one end of the limiting bolt is threadedly connected with the centering bushing, and the other end is threadedly connected with the stator connecting mechanism; the sector body is provided with a positioning tooth at the front end, the positioning tooth is matched with the tooth groove of the high-pressure turbine rear shaft for limiting, and the rear end is provided with a sector block with an arc-shaped groove; the arc-shaped groove is matched with the torque screw for clamping to fix the angular position of the rotor; the torque screw is coaxially arranged with the sector body, and one end of the torque screw is inserted into the inside of the sector body and threadedly matched with the high-pressure turbine rear shaft.

[0009] Preferably, the stator connecting mechanism is connected with a welded assembly of the high-pressure turbine and the combustion chamber box, the welded assembly comprises a front limiting nut, a rear limiting nut and a flat key; the inside of the welded assembly is provided with a mounting edge, the inner wall of the mounting edge is attached to the limiting bolt, the inner wall of the mounting edge is provided with a key groove, the limiting bolt is provided with a tooth groove at the position corresponding to the key groove, and the flat key is arranged between the key groove and the tooth groove; the front limiting nut and the rear limiting nut are respectively arranged on the front and rear sides of the mounting edge, and the front limiting nut and the rear limiting nut are both threadedly connected with the outer wall of the limiting bolt.

[0010] Preferably, the outer wall of the mounting edge is connected with a reverse support seat through a bolt.

[0011] Preferably, a hoisting trunnion is horizontally arranged between the outer wall of the high-pressure turbine rear shaft and the mounting edge, and the hoisting trunnion is provided with a hoisting interface; a parking car adapter and a reinforcing rod are obliquely arranged between the outer wall of the high-pressure turbine rear shaft and the mounting edge, the reinforcing rod is connected with the rotor connecting mechanism, the parking car adapter is connected with the outer wall of the mounting edge, and the parking car adapter and the hoisting trunnion are in the same plane.

[0012] Preferably, the outer side of the high-pressure turbine rear shaft is provided with a pressing mechanism, the pressing mechanism comprising a pressing nut and a wrench driving head, the wrench driving head being connected with the stator connecting mechanism through the pressing nut, and the wrench driving head being provided with a square hole for wrench driving.

[0013] Preferably, the centering bushing is made of fluoroplastic material.

[0014] The centering device of the large-bypass-ratio engine core machine provided in the application comprises a rotor connecting mechanism and a stator connecting mechanism, the rotor connecting mechanism comprising a centering bushing, a limiting bolt, a sector body and a torque screw, the stator connecting mechanism comprising a front limiting nut, a rear limiting nut and a flat key, the adjustable positioning being realized through the double-thread structure of the limiting bolt, and the axial positioning and adjustment requirement being realized through the axial pressing of the torque screw, the front limiting nut and the rear limiting nut. The radial positioning and supporting structure are separated, the radial positioning of the rotor and the stator is realized by using the cylindrical surface of the grate part and the installation edge bolt of the stator casing, and the torque screw matched with the inner thread of the shaft rear end is used to avoid the damage of the grate part due to the excessive pressure, the contact end surface after the tightening of the torque screw prevents the inclination caused by the sinking of the rear end of the rotor, and the axial, radial relative positioning and the angular, axial position adjustment functions between the rotor and the stator are realized. BRIEF DESCRIPTION OF DRAWINGS

[0015] In order to more clearly illustrate the technical solutions provided in the application, the following will briefly introduce the drawings. Obviously, the drawings described below are only some embodiments of the application.

[0016] Figure 1 It is a schematic diagram of the horizontal installation of the core machine in the background art;

[0017] Figure 2 It is a schematic diagram of the assembly of the centering casing of the small-bypass-ratio engine core machine in the background art;

[0018] Figure 3 It is a front view of the overall structure of the application;

[0019] Figure 4 It is a sectional view of the overall structure of the application;

[0020] Figure 5 It is a sectional view of the rotor connecting mechanism and the stator connecting mechanism of the application.

[0021] 1, centering bushing; 2, limiting bolt; 3, sector body; 4, torque screw; 5, pressing nut; 6, wrench driving head; 7, front limiting nut; 8, rear limiting nut; 9, flat key; 10, hoisting ear shaft; 11, parking car adapter; 12, reinforcing rod; 13, reverse support seat; 14, welded assembly; 15, high-pressure turbine rear shaft; 16, installation edge. DETAILED DESCRIPTION

[0022] With reference to the accompanying drawings: the technical solutions in the embodiments of the present application will be apparently and completely described, obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work belong to the scope of protection of the present application.

[0023] A large-bypass-ratio engine core centering device, as shown in Figures 3-5 The high-pressure turbine casing and the combustion chamber casing are connected through the welding assembly 14, the rear shaft of the high-pressure turbine has more grids but no bolt or other structure that can be directly used for connection, and due to the need for subsequent installation of the air duct and the No. 4 bearing outer ring, the centering device still needs to have radial support after the core engine is assembled in place but cannot occupy the internal structure of the rear shaft of the high-pressure turbine, that is, the radial positioning after the core engine is assembled in place cannot use the internal threads of the rear shaft of the high-pressure turbine. Under this condition, the following functions need to be realized at the same time:

[0024] 1. Axial and radial relative positioning function between the rotor and the stator.

[0025] 2. Angular relative position adjustment function, so that the front end external spline of the rotor cooperates with the internal spline of the driving bevel gear.

[0026] 3. Axial positioning adaptation function: adapt to the different position requirements of the axial relative position of the rotor and the stator at different stages of installation, that is, before horizontal installation, satisfy the relative position of the rotor and the stator that has been guaranteed during the assembly process of the core engine, and ensure that the rotor is contacted first during the installation process.

[0027] 4. Centering function of the front end of the rotor in cooperation with the wrench before the core engine is installed, providing support for the core engine.

[0028] Including a rotor connecting mechanism and a stator connecting mechanism, installed after the vertical assembly of the core engine unit body is completed.

[0029] The rotor connecting mechanism comprises a centering bush 1, a limiting bolt 2, a sector body 3 and a torque screw 4. The centering bush 1 is made of fluoroplastic material, which is heat-resistant, wear-resistant and has good insulation performance. The centering bush 1 is matched with the cylindrical surface of the high-pressure turbine rear shaft 15 to realize centering, and is matched with the toothed structure to realize positioning. The limiting bolt 2 is a double-headed screw thread, one end of which is threadedly connected with the centering bush 1 and the other end of which is threadedly connected with the stator connecting mechanism. The sector body 3 is provided with a positioning tooth at the front end, which is matched with the toothed groove of the high-pressure turbine rear shaft 15 to limit the position, and is provided with a sector block with an arc-shaped groove at the rear end, which is matched with the torque screw 4 to fix the angular position of the rotor. The outer side of the high-pressure turbine rear shaft 15 is provided with a pressing mechanism, which comprises a pressing nut 5 and a wrench driving head 6. The wrench driving head 6 is connected with the stator connecting mechanism through the pressing nut 5. The wrench driving head 6 is provided with a square hole for wrench driving. After the pressing nut 5 is loosened, the wrench can be installed on the driving head to drive the sector body 3 and the rotor to rotate. After the pressing nut 5 is tightened, the angular position of the rotor is fixed.

[0030] The torque screw 4 is coaxially arranged with the sector body 3. One end of the torque screw 4 is inserted into the inner side of the sector body 3 and the inserted part is threadedly matched with the high-pressure turbine rear shaft 15. The torque screw 4 is tightened to ensure that the end faces of the torque screw 4, the sector body 3 and the limiting bolt 2 are in contact and pressed.

[0031] The stator connecting mechanism comprises a front limiting nut 7, a rear limiting nut 8 and a flat key 9. The outer end of the welded assembly 14 is matched with the high-pressure turbine casing and the combustion chamber casing through a flange. The inner part of the welded assembly 14 is provided with a mounting edge 16. The inner wall of the mounting edge 16 is attached to the limiting bolt 2. The inner wall of the mounting edge 16 is provided with a key groove. The limiting bolt 2 is provided with a toothed groove at the position corresponding to the key groove. The flat key 9 is arranged between the key groove and the toothed groove, which realizes the angular positioning of the limiting bolt 2 and the mounting edge 16, and provides a counter-torque when the front limiting nut 7 and the rear limiting nut 8 are rotated.

[0032] The front limiting nut 7 and the rear limiting nut 8 are respectively arranged on the front and rear sides of the mounting edge 16, and are threadedly connected with the outer wall of the limiting bolt 2, which realizes the axial positioning of the mounting edge 16 and the limiting bolt 2. By rotating the front limiting nut 7 and the rear limiting nut 8 to different mounting positions on the limiting bolt 2, the axial position of the rotor connecting mechanism can be adjusted.

[0033] A lifting lug shaft 10 is horizontally arranged between the high-pressure turbine rear shaft 15 and the outer wall of the mounting edge 16, and a lifting interface is arranged on the lifting lug shaft 10 to provide an interface for a horizontal lifting device of the core machine unit body. A parking vehicle adapter 11 and a reinforcing rod 12 are arranged between the high-pressure turbine rear shaft 15 and the outer wall of the mounting edge 16, the reinforcing rod 12 is connected with the rotor connecting structure, the parking vehicle adapter 11 is connected with the outer wall of the mounting edge 16, the parking vehicle adapter 11 is in the same plane as the lifting lug shaft 10, and the reinforcing rod 12 mainly bears pressure rather than shear force through the inclined surface contact mode, so that the structural strength is improved.

[0034] And a reverse support seat 13 is connected to the outer wall of the mounting edge 16 through bolts, so that the core machine unit body can be parked in an upward posture.

[0035] The application can be adjusted and positioned through the double-thread structure of the limiting bolt 2, and the axial positioning and adjustment requirements can be realized through the axial compression of the torque screw 4, the front limiting nut 7 and the rear limiting nut 8. The radial positioning and supporting structure are separated, the cylindrical surface of the labyrinth part and the bolt of the stator casing mounting edge 16 are used to realize the radial positioning of the rotor and stator, and the torque screw 4 matched with the inner thread of the shaft rear end is used to avoid damage of the labyrinth part due to bearing of excessive pressure. The contact end surface after tightening of the torque screw 4 prevents the inclination caused by the sinking of the rear end of the rotor. The tooth groove on the limiting bolt 2 is used as a force point to realize the adjustment of the angular position of the rotor, and a compression structure is arranged to control the adjustable state of the angular position. Therefore, the axial and radial relative positioning between the rotor and the stator, the angular and axial position adjustment function are realized, and the realization of the horizontal installation scheme of the whole machine is ensured.

[0036] The device is installed to the core machine after the vertical assembly of the core machine unit body is completed, and as a specific embodiment, the specific operation steps of the device are as follows:

[0037] 1) The rear torque screw 4, the compression nut 5 and the sector 3 are removed;

[0038] 2) The front limiting nut 7 is rotated to be at the frontmost position, and the rear limiting nut 8 is rotated to be flush with the rear end surface of the limiting bolt 2;

[0039] 3) The device is installed to the high-pressure turbine casing through the centering bushing 1 and is aligned at the uppermost position;

[0040] 4) The front limiting nut 7 and the rear limiting nut 8 are tightened;

[0041] 5) The sector 3 is installed and the teeth on the front end surface of the sector 3 are matched with the tooth groove on the rear end surface of the high-pressure turbine rear shaft 15, and the compression nut 5 is tightened to fix the sector 3;

[0042] 6) The torque screw 4 is installed and tightened, and the end surfaces of the torque screw 4, the sector 3 and the limiting bolt 2 are in contact and compression.

[0043] Before the core machine is installed in place, that is, when there is a gap of 3±0.5 mm between the front installation edge 16 of the core machine unit body and the rear installation edge 16 of the fan main unit body, the front limiting nut 7 and the rear limiting nut 8 are each loosened by 2-3 turns to allow the core machine rotor-stator to have a certain amount of axial movement, so as to prevent the rotor from being affected by the stator and failing to be installed in place, and then a wrench is used to limit the front nut of the shaft.

[0044] Finally, it should be noted that the drawings of the disclosed embodiments only involve the structures involved in the disclosed embodiments, and other structures can refer to the usual design. In the case of no conflict, the same embodiment and different embodiments of the present application can be combined with each other;

[0045] Finally, the above only describes the preferred embodiments of the present application and is not intended to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A high bypass ratio engine core centering device characterized by: The rotor connecting mechanism and the stator connecting mechanism, the rotor connecting mechanism comprises a centering bushing (1), a limiting bolt (2), a sector (3) and a torque screw (4); the centering bushing (1) is matched with the cylindrical surface of the comb structure of the high-pressure turbine rear shaft (15) to center, the limiting bolt (2) is double-headed thread, one end of the limiting bolt (2) is threadedly connected with the centering bushing (1), and the other end is threadedly connected with the stator connecting mechanism; the sector (3) is provided with a positioning tooth at the front end, the positioning tooth is matched with the tooth groove of the high-pressure turbine rear shaft (15) to limit, and the rear end is provided with a sector block with an arc-shaped groove; the arc-shaped groove is matched with the torque screw (4) to be clamped, and is used for fixing the angular position of the rotor; the torque screw (4) is coaxially arranged with the sector (3), one end of the torque screw (4) is inserted into the inner side of the sector (3), and the inserted part is threadedly matched with the high-pressure turbine rear shaft (15); The stator connecting structure is connected with the welded assembly (14) of the high-pressure turbine and the combustion chamber case, and comprises a front limiting nut (7), a rear limiting nut (8) and a flat key (9); the inside of the welded assembly (14) is provided with a mounting edge (16), the inner wall of the mounting edge (16) is attached to the limiting bolt (2), the inner wall of the mounting edge (16) is provided with a key groove, the limiting bolt (2) is provided with a tooth groove at the position corresponding to the key groove, and the flat key (9) is arranged between the key groove and the tooth groove; the front limiting nut (7) and the rear limiting nut (8) are arranged on the front and rear sides of the mounting edge (16) respectively, and the front limiting nut (7) and the rear limiting nut (8) are threadedly connected with the outer wall of the limiting bolt (2); The outer side of the high-pressure turbine rear shaft (15) is provided with a pressing mechanism, the pressing mechanism comprises a pressing nut (5) and a wrench driving head (6), the wrench driving head (6) is connected with the stator connecting mechanism through the pressing nut (5), and the wrench driving head (6) is provided with a square hole for wrench driving.

2. The high bypass ratio engine core centering device of Claim 1, wherein: The outer wall of the mounting edge (16) is connected with a reverse supporting seat (13) through a bolt.

3. The high bypass ratio engine core centering device of claim 1, wherein: A hoisting trunnion (10) is horizontally arranged between the high-pressure turbine rear shaft (15) and the outer wall of the mounting edge (16), and the hoisting trunnion (10) is provided with a hoisting interface; a parking car adapter (11) and a reinforcing rod (12) are obliquely arranged between the high-pressure turbine rear shaft (15) and the outer wall of the mounting edge (16), the reinforcing rod (12) is connected with the rotor connecting mechanism, the parking car adapter (11) is connected with the outer wall of the mounting edge (16), and the parking car adapter (11) and the hoisting trunnion (10) are in the same plane.

4. The high bypass ratio engine core centering device of claim 1, wherein: The centering bushing (1) is made of fluoroplastic material.

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