Tool and method for disassembling conical bolt of high-pressure turbine rotor of aero-engine

Abstract

The invention discloses an aero-engine high-pressure turbine rotor conical bolt disassembling tool and method. The disassembling tool comprises an arch-shaped frame, a movable contact head and a transmission rod. When the conical bolt is disassembled, one supporting arm of the arch-shaped frame is tightly attached to and seals the end face of the labyrinth disc, then the transmission rod is rotated, and the movable contact head is driven to apply linear pressure to the end face of the conical bolt till the conical bolt is ejected out. The disassembling efficiency of aero-engine components is improved, the loss of the engine components caused by impact operation in the disassembling process is reduced, meanwhile, the service life of the high-pressure turbine rotor assembly is further prolonged, and the consistency in the follow-up assembling process is guaranteed.

Description

Technical Field

[0001] The invention belongs to the technical field of aeroengine assembly, and in particular relates to a device and a method for disassembling conical bolts on a high-pressure turbine rotor during aeroengine disassembly. Background Art

[0002] The structure of aircraft engines is complex and requires high precision, and there are high quality requirements during the assembly process. In the engine, the function of the turbine is to expand the high-temperature and high-pressure combustion gas to do work, convert part of the heat energy in the combustion gas into mechanical energy, and output turbine work to drive the compressor and other accessories.

[0003] The characteristics of aviation gas turbines are high power, high gas temperature, high speed and heavy load. The turbine output power of modern high-thrust turbofan engines is as high as 100MW or more, and the average power output of a turbine blade is as high as 200KW. To improve the performance of aviation gas turbine engines with small size and light weight, one of the main measures is to use higher gas temperature. Because of this, the turbine components (especially the rotor parts) are subject to great mechanical loads and have poor working conditions. It is one of the components with more failures during engine use.

[0004] Nowadays, most turbine rotor connections are detachable, which is beneficial to improving the assembly characteristics of the rotor. The detachable connection methods mainly include short bolt connection, long bolt connection and integral shaft-disc connection using a short shaft. In order to facilitate disassembly and assembly, simple structure, and reliable connection centering and torque transmission, long bolts are mostly used for connection between disks. To ensure the accuracy of assembly, bolts will use precision bolts with precision machined surfaces at the connection surfaces between disks to ensure the docking accuracy between disks and achieve the reproduction of the balanced state of the high-pressure rotor in the formal assembly. On this basis, in order to further improve the connection strength and accuracy and ensure that the preload force between disks in the assembly state is evenly distributed, the precision bolts will be made into a cone, and the interference fit is controlled to ensure that the bolts and the mounting edge are matched. Conical precision bolts are suitable for models with multiple assembly requirements and are widely used in many engines.

[0005] like Figure 1 As shown in the figure, the high-pressure turbine rotor assembly of the engine is composed of high-pressure turbine disc, sealing grate disc, retaining ring, rear journal, diaphragm, grate ring and multiple pairs of left and right blades. The high-pressure turbine disc, rear journal and sealing grate disc are fixed to the drum shaft through multiple tapered bolts, and the holes are 1:50 tapered connection holes.

[0006] Bolts can achieve connections that can be disassembled and reassembled multiple times, and well-designed connections can transmit huge forces without failure. The tapered bolts of aircraft engines fix the high-pressure turbine rotor assembly through interference fit. During the disassembly process, the interference must be offset to separate the tapered bolts. Currently, due to the lack of special tooling, the only way to disassemble them is by hammering. During disassembly, the tapered bolts cannot be easily separated due to the interference fit of the tapered bolts. Therefore, a hammer is used to knock on the top of the tapered bolt, and the thread is less than 1mm away from the top of the bolt. The thread, the end face of the bolt, and the comb teeth are easily damaged during the knocking process. Summary of the invention

[0007] The present invention aims to provide a tool and method for disassembling the conical bolts of a high-pressure turbine rotor of an aircraft engine, so as to avoid the disassembly of the high-pressure turbine rotor connecting parts (conical bolts) by knocking, improve the disassembly efficiency of aircraft engine components, reduce the loss of engine components caused by impact during the disassembly process, and further improve the service life of parts.

[0008] To achieve the above object, the present invention adopts the following technical solutions:

[0009] Aircraft engine high pressure turbine rotor conical bolt disassembly tooling, including:

[0010] An arch frame, the arch frame comprising a first arm and a second arm arranged in parallel, a clamping space formed between the first arm and the second arm, a threaded hole being formed on the first arm, and an axis of the threaded hole not intersecting with the second arm;

[0011] A transmission rod, the transmission rod comprising a screw rod and a rotating handle, wherein the screw rod is installed in the threaded hole of the first arm, and the axial first end of the screw rod points to the second arm, and the axial second end of the screw rod is vertically connected to the rotating handle;

[0012] A movable contact head is connected to the axial first end of the screw rod and is gap-fitted, and a surface of the movable contact head away from the screw rod forms an end face in contact with the conical bolt.

[0013] As a solution:

[0014] One end of the screw rod connected to the movable contact head is T-shaped;

[0015] The end surface of the movable contact head is provided with a T-shaped through groove, and the screw rod is assembled in the T-shaped through groove via the T-shaped end.

[0016] As a solution, the bow frame is made of industrial pure aluminum.

[0017] As a solution, the end surface of the movable contact head that contacts the conical bolt is a plane.

[0018] The method for disassembling the conical bolts of the high-pressure turbine rotor of an aircraft engine adopts the above-mentioned disassembly tool and comprises the following steps:

[0019] S1, insert the second arm of the arch frame between the sealing grate disc and the rear journal of the high-pressure turbine disc, and fit it to the end face edge of the sealing grate disc;

[0020] S2, quickly turn the rotary handle to drive the first axial end of the screw to move toward the sealing grate disc until the movable contact head contacts the conical bolt;

[0021] S3: Keep slowly turning the rotary handle in the same direction as S2 until the conical bolt withdraws from the rear journal end face of the high-pressure turbine disk.

[0022] At present, there is no special tooling for disassembling the conical bolts on the high-vortex rotor assembly, and they can only be disassembled by hammering. The disassembly process is prone to damage to the bolt end face, thread and comb teeth due to hammering. The present invention is fixed by a bow frame, and then contacts the conical bolt end face through a transmission rod and a movable contact head. The clearance between the movable contact head and the transmission rod can ensure that the force of the transmission rod acts nearly vertically on the end face of the conical bolt, and then gradually applies a disassembly torque to separate the conical bolt with a linearly increasing pressure, thereby protecting the sealing comb teeth and the conical bolt end face and thread, and also ensuring the measurement accuracy of the protruding amount of the engine conical bolt. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of the structure of the decomposition tooling in the present invention;

[0024] In the figure, 1-bow frame, 2-nameplate, 3-movable contact head, 4-nameplate fixing screw, 5-transmission rod. DETAILED DESCRIPTION

[0025] The present invention is further described below in conjunction with specific embodiments, but it should not be understood that the scope of the subject matter described in the present invention is limited to the following embodiments. Without departing from the above-mentioned technical ideas of the present invention, various modifications, substitutions and changes made according to common technical knowledge and customary means in the field are included in the scope of the present invention.

[0026] In view of the fact that the conventional decomposition of conical bolts in the process of engine assembly and decomposition can only be done by hammering, which will damage the end face, thread and comb teeth of the bolts, thus affecting the quality of secondary assembly. Therefore, the present invention designs a decomposition tool for conical bolts, such as Figure 1As shown, it includes an arch frame 1, a nameplate 2, a movable contact head 3, a nameplate fixing screw 4 and a transmission rod 5. The arch frame 1 includes a first arm and a second arm arranged in parallel, one end of the first arm and the second arm are connected to form a handle part held by an operator, the length of the first arm is greater than the second arm, and there is a threaded hole on the first arm, in which a transmission rod 5 is installed, and the end of the transmission rod 5 is detachably installed with a movable contact head 3, wherein the end of the transmission rod 5 is T-shaped, and a T-shaped through groove is opened on the end face of the movable contact head 3, and the T-shaped end is inserted into the T-shaped through groove to form a clearance fit. The nameplate 2 is installed on the surface of the handle part by the nameplate fixing screw 4.

[0027] The disassembly tool can prevent the damage to the tapered bolt end face, tapered bolt thread and comb teeth caused by knocking, and ensure the measurement accuracy of the bolt protrusion. When the disassembly tool is working, it contacts the bolt end face through the movable contact head 3, gradually applies the disassembly torque, and separates the bolt with linearly increasing pressure.

[0028] The bow frame 1 in the disassembly tool is made of industrial pure aluminum to avoid damage to the sealing grate teeth during the disassembly process.

[0029] Operation method: The end face of the bolt is contacted through the transmission rod 5 and the movable contact head 3. The end face of the movable contact head 3 is a plane. Since it is a clearance fit with the transmission rod 5, a certain amount of movable margin is reserved to ensure that the plane end face of the movable contact head 3 is completely fitted with the end face of the tapered bolt, so that the applied force is vertically transmitted to the tapered bolt, reducing the influence of the interference fit resistance (friction force) of the tapered bolt and improving the decomposition efficiency. The transmission rod 5 is rotated to gradually apply the decomposition torque to decompose the bolt with a linearly increasing pressure.

[0030] like Figure 1 As shown, the disassembly tool consists of a transmission rod 5, a movable contact head 3 and a bow frame 1. The bow frame 1 is fixed to the edge of the lower end surface of the sealing grate tooth plate. The transmission rod 5 is rotated to gradually tighten the end surface of the conical bolt through the movable contact head 3, and the conical bolt is separated by the increasing pressure, thereby protecting the sealing grate teeth and the bolt end surface and thread, and ensuring the measurement accuracy of the engine bolt protrusion.

[0031] The high-vortex rotor assembly includes multiple conical bolts. The protrusion of the conical bolts relative to the table surface during the engine assembly process is a key control point. The protrusion of the bolts is needed to ensure the consistency of the engine's high-pressure rotor assembly in a balanced state, that is, the protrusions of multiple numbered conical bolts are measured and divided after balancing is completed, and the high-pressure rotor is assembled again during assembly. It is required that the protrusions of multiple conical bolts measured twice during balancing and assembly must match to ensure that the assembly state can reproduce the state at the time of balance. When decomposing the conical bolts after balancing, it is necessary to knock on the end face of the conical bolt (i.e., the end face where the protrusion is measured), which will affect the judgment of whether the protrusions match during assembly. This key problem can be solved by using the decomposition tooling of the present invention.

[0032] Fix the disassembly tool to the comb teeth and conical bolts of the rear journal of the high-pressure turbine rotor assembly, turn the rotary handle, and remove the conical bolt by linearly increasing pressure (the impact load of hammering is a sudden change from 0 to 1, while the pressure process of rotating the transmission rod 5 and using the thread of the transmission rod 5 connected to the bow frame 1 to apply force to the end face of the conical bolt is continuous and linear), thereby avoiding damage to the sealing comb teeth and inaccurate measurement of the bolt protrusion caused by hammering during the disassembly process.

[0033] The contents not described in detail in the specification of the present invention belong to the prior art known to the professional and technical personnel in the field. Although the illustrative specific embodiments of the present invention are described above to facilitate the understanding of the present invention by the technical personnel in the field, it should be clear that the present invention is not limited to the scope of the specific embodiments. For ordinary technicians in the field of this technology, as long as various changes are within the spirit and scope of the present invention defined and determined by the attached claims, these changes are obvious, and all inventions and creations using the concept of the present invention are protected.

Claims

1. The conical bolt disassembly tool for high-pressure turbine rotor of aircraft engine is characterized by: include: An arch frame (1), the arch frame (1) comprising a first arm and a second arm arranged in parallel, a clamping space formed between the first arm and the second arm, a threaded hole being formed on the first arm, and an axis of the threaded hole not intersecting with the second arm; A transmission rod (5), the transmission rod (5) comprising a screw and a rotating handle, wherein the screw is installed in the threaded hole of the first support arm, and the axial first end of the screw points to the second support arm, and the axial second end of the screw is vertically connected to the rotating handle; A movable contact head (3) is connected to the axial first end of the screw rod and is gap-fitted; a surface of the movable contact head (3) away from the screw rod forms an end face in contact with the conical bolt.

2. The aircraft engine high pressure turbine rotor conical bolt disassembly tool according to claim 1, characterized in that: One end of the screw rod connected to the movable contact head (3) is in a T shape; The end surface of the movable contact head (3) is provided with a T-shaped through groove, and the screw rod is assembled in the T-shaped through groove via the T-shaped end.

3. The aircraft engine high pressure turbine rotor conical bolt disassembly tool according to claim 1, characterized in that: The material of the bow-shaped frame (1) is industrial pure aluminum.

4. The aircraft engine high pressure turbine rotor conical bolt disassembly tool according to claim 1, characterized in that: The end surface of the movable contact head (3) in contact with the conical bolt is a plane.

5. A method for disassembling conical bolts of a high-pressure turbine rotor of an aircraft engine, characterized in that: The disassembly tool according to claim 1 is used, and includes the following steps: S1, inserting the second arm of the bow frame (1) between the sealing grate disc and the rear journal of the high-pressure turbine disc, and fitting it to the end face edge of the sealing grate disc; S2, quickly turning the rotary handle to drive the first axial end of the screw to move toward the sealing grate disc until the movable contact head (3) contacts the conical bolt; S3: Keep slowly turning the rotary handle in the same direction as S2 until the conical bolt withdraws from the rear journal end face of the high-pressure turbine disk.

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