High-precision auxiliary installation tool and installation method for aircraft engine turbine support

Abstract

The present invention discloses a high-precision auxiliary installation tool and installation method for an aircraft engine turbine support. The installation tool is mainly composed of a support, a precision guide pin, a guide pin and a limit pin. The support is an inverted triangle-arc structure, and the precision guide pin and the guide pin correspond to the precision hole and the ordinary hole on the turbine support respectively. During installation, the support of the high-precision auxiliary installation tool is evenly installed on the rear installation edge of the low-pressure turbine guide on the main engine, and the guide pin is inserted into the support to guide the ordinary hole on the turbine support; then the precision guide pin is inserted from top to bottom to guide the precision hole on the turbine support, and then the limit pin is inserted into the support to lock the precision guide pin and the guide pin; after completing the installation of the tool, the turbine support is vertically hoisted by a crane. The present invention has the characteristics of precise guidance, which improves the assembly efficiency and quality of the engine.

Description

Technical Field

[0001] The invention belongs to the technical field of aircraft engine complete machine assembly and test running, and specifically relates to a high-precision auxiliary installation tool and an installation method for an aircraft engine turbine support. Background Art

[0002] In the assembly of aircraft engines, the graphite components on the turbine bearings are very precisely matched with their bearings, with a clearance of less than 0.05mm. It is difficult to control the centering of the turbine bearings during installation, so problems such as bearing damage and graphite falling off often occur, affecting the assembly quality of the engine, delaying the progress of scientific research, and causing high manufacturing costs. In the past, in the process of assembling turbine bearings of various types of engines, quality accidents often occurred due to the lack of proper guidance during lifting, resulting in deviation from the center and damage to the graphite ring, causing great losses.

[0003] The turbine support is mainly assembled and connected to the engine body through the low-pressure turbine guide. Both the turbine support and the low-pressure turbine guide are processed with precision holes and ordinary holes. Both the precision holes and ordinary holes are through holes with smooth inner walls. The difference lies in the different processing accuracy. After the turbine support and the low-pressure turbine guide are aligned, they are connected by precision bolts and ordinary bolts.

[0004] Based on the above reasons, it is necessary to design a process device and assembly method for high-precision auxiliary installation of turbine bearings for aircraft engines according to the structural characteristics of the engine turbine bearings and the problems existing in the transmission and assembly process, so as to improve the assembly efficiency and quality of the engine. Summary of the invention

[0005] In order to solve the above technical problems, the present invention aims to provide a high-precision auxiliary installation tool and installation method for an aircraft engine turbine support, which has the characteristics of precise guidance and can achieve the function of high-quality and rapid disassembly and assembly of the turbine support.

[0006] The present invention adopts the following technical solutions:

[0007] High-precision auxiliary installation tools for aircraft engine turbine bearings, including:

[0008] The support is a fan-shaped structure with a central angle less than 180°, and includes a first fitting surface for fitting the lower end surface of the rear mounting edge of the low-pressure turbine guide vane, and a second fitting surface for fitting the protrusion on the circumferential outer surface of the low-pressure turbine guide vane. The first fitting surface is provided with a through hole that penetrates the support, and the support is also provided with a limiting hole, and the limiting hole is connected to the through hole; the fan-shaped structure is adopted in consideration of the shape of the mounting edges (both are circular) of the low-pressure turbine guide vane and the turbine support, and the central angle of the fan-shaped structure is less than 180°, the purpose of which is to reduce the deadweight and volume of the auxiliary tool, and at the same time facilitate the adjustment of its installation position to determine the assembly plane. The support adopts a split structure, which is used in combination of multiple identical auxiliary tools, and only occupies a very small part of the circumferential length of the mounting edges of the low-pressure turbine guide vane and the turbine support to complete the auxiliary alignment.

[0009] A precision guide pin, the precision guide pin comprising a first insertion section and a first guide section, the first insertion section is inserted in the through hole, the outer diameter of the first guide section is larger than the inner diameter of the through hole, and the outer diameter of the first guide section matches the inner diameter of the precision hole on the turbine bearing;

[0010] A guide pin, the guide pin comprising a second insertion section and a second guide section, the second insertion section is inserted into the through hole, the outer diameter of the second guide section is larger than the inner diameter of the through hole, and the outer diameter of the second guide section matches the inner diameter of a common hole on the turbine support;

[0011] The limiting pin, when the limiting pin is inserted into the limiting hole, the end of the limiting pin is in close contact with the surface of the first insertion section and the surface of the second insertion section.

[0012] As an option, one of the supports has three through holes and three limiting holes, wherein the central through hole is used for a precision guide pin, and the through holes on both sides are used for guide pins.

[0013] As an option, the first insertion section and the first guide section have a chamfer at their transition, the second insertion section and the second guide section have a chamfer at their transition, and the through hole has a chamfer at its opening at one end of the first fitting surface.

[0014] As an option, the ends of the first insertion section and the second insertion section inserted into the through hole are both chamfered, and the surfaces of the first insertion section and the second insertion section include at least one plane.

[0015] As an option, the first guide segment and the second guide segment further include an outer diameter gradient segment with a gradually decreasing outer diameter.

[0016] As an option, the cross-sectional shape of the support is trapezoidal, with the first fitting surface as the longer bottom edge and the second fitting surface as the shorter top edge. The use of this trapezoidal cross-sectional structure helps to reduce the deadweight and volume occupied by the support, avoiding falling due to excessive weight or deforming the boss on the surface of the low-pressure turbine guide vane. The small-volume support is convenient for mobile installation on the one hand, and convenient for storage and management on the other.

[0017] As an option, the shape contour of the surface of the support corresponding to the circumferential outer surface of the low-pressure turbine guide vane is processed according to the circumferential outer surface of the low-pressure turbine guide vane, thereby avoiding the structural shape on the circumferential outer surface of the low-pressure turbine guide vane.

[0018] The turbine bearing installation method using the aforementioned high-precision auxiliary installation tool for the aircraft engine turbine bearing comprises the following steps:

[0019] Step 1: Determine the number of sets of high-precision auxiliary installation tools for the aircraft engine turbine support according to the number of precision holes and common holes on the front mounting edge of the turbine support, and install the supports in multiple sets of auxiliary installation tools evenly distributed along the radial direction of the low-pressure turbine guide vane on the outer side of the circumferential surface of the low-pressure turbine guide vane on the main engine, and the first fitting surface is in close contact with the lower end surface of the rear mounting edge of the low-pressure turbine guide vane, and the second fitting surface is in close contact with the raised end surface on the circumferential outer surface of the low-pressure turbine guide vane;

[0020] Step 2: insert the guide pin and the precision guide pin into the through hole from top to bottom, and then insert the limit pin into the limit hole of the support to lock the guide pin and the precision guide pin;

[0021] Step three: vertically lift the turbine support by crane. During the process, ensure that the precision holes on the turbine support match the precision guide pins. Slowly lower the turbine support under the guidance of the precision guide pins until it fits with the rear mounting edge of the low-pressure turbine guide vane. Then remove the precision guide pins and guide pins from above in turn, and then remove the support to complete the guided assembly of the turbine support.

[0022] Preferably, in step one, the number of sets of high-precision auxiliary installation tools for aircraft engine turbine supports is 3 sets.

[0023] Preferably, in step 2, a precision guide pin having a first guide section with a gradually changing outer diameter section and a guide pin having a second guide section with a gradually changing outer diameter section are used.

[0024] It should be pointed out that the structure of the precision guide pin is consistent with that of the guide pin. The difference is that the precision guide pin is matched with the precision hole with high precision, while the guide pin is matched with the ordinary hole with low precision.

[0025] Compared with the prior art, the precise installation of the turbine bearing of the present invention is achieved by guiding a tool with high precision to assist in installing the turbine bearing, and has the following characteristics:

[0026] (1) The support adopts a fan-shaped structure with a trapezoidal cross-section, which can be closely attached to the rear mounting edge of the low-pressure turbine guide vane casing (i.e., the turbine support connection mounting edge), and does not need to be fixed by additional auxiliary devices (the support is closely attached between the mounting edge and the boss on the outer side of the low-pressure turbine guide vane through two fitting surfaces, and can be fixed by inserting guide pins and precision guide pins). It is evenly installed on the low-pressure turbine guide vane casing, which is convenient for installation and removal;

[0027] (2) The guide part (precision guide pin and guide pin) and the support are separate structures. The precision guide pin and the guide pin are inserted into the through holes on the support respectively to achieve guidance. After the guidance is completed, they can be directly pulled out from the through holes to achieve disassembly. The support is directly removed from the circumferential outer surface of the low-pressure turbine guide vane;

[0028] (3) The corresponding precision holes on the turbine support are installed correspondingly with the precision guide pins, and the common holes are installed correspondingly with the guide pins. The turbine support is highly precisely aligned to achieve precise guidance.

[0029] The present invention facilitates the installation and removal of the turbine support, has high guiding accuracy, improves the assembly quality of the engine, and can effectively avoid the occurrence of collision damage to graphite or bearings. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is the general assembly structure diagram of the tool used for high-precision auxiliary installation of turbine bearings for aircraft engines;

[0031] Figure 2 is a schematic diagram of the support structure;

[0032] Figure 3 It is a schematic diagram of the structure of the precision guide pin and the guide pin;

[0033] In the figure, 1-support; 2-precision guide pin; 3-guide pin; 4-limiting pin; 11-first fitting surface; 12-second fitting surface; 13-avoidance surface; 14-weight-reducing cone surface; 15-through hole; 16-limiting hole. DETAILED DESCRIPTION

[0034] The present invention is further described below in conjunction with the accompanying drawings and 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 the common technical knowledge and customary means in the field are included in the scope of the present invention.

[0035] like Figure 1 to Figure 3 As shown, a set of high-precision auxiliary installation tools for aircraft engine turbine bearings consists of a support 1 (1 piece), a precision guide pin 2 (1 piece), a guide pin 3 (2 pieces) and a limit pin 4 (3 pieces).

[0036] The support 1 is a fan-shaped structure with a trapezoidal cross section, and a through hole 15 and a stop hole 16 are formed on the support 1, and the stop hole 16 is vertically connected to the through hole 15; the central angle of the fan-shaped structure is less than 180°, that is, there is only a small arc, the purpose is to partially cover the circumferential surface of the low-pressure turbine guide vane, rather than covering it completely, thereby reducing the weight and volume occupied by the tool. Figure 2 The cross section of the support 1 is trapezoidal, the first fitting surface 11 is the bottom surface of the trapezoid and has a longer length, the second fitting surface 12 is the top edge of the trapezoid and has a shorter length, the weight-reducing conical surface 14 is the weight-reducing structure and the outer surface of the support 1, and cooperates with the through hole 15 to make the center of gravity of the support 1 closer to the avoidance surface 13, and the avoidance surface 13 is the surface of the support 1 close to the circumferential outer surface of the low-pressure turbine guide vane. The shape of the avoidance surface 13 is processed according to the contour of the circumferential outer surface of the low-pressure turbine guide vane to avoid the structure of the circumferential outer surface of the low-pressure turbine guide vane. When in use, the weight-reducing conical surface 14 of the support 1 faces outward, the avoidance surface 13 faces inward, the first fitting surface 11 is in close contact with the lower end surface of the rear mounting edge of the low-pressure turbine guide vane, and the second fitting surface 12 is in close contact with the end surface of the boss structure on the circumferential outer surface of the low-pressure turbine guide vane, so that the support 1 is between the two surfaces.

[0037] like Figure 3 The precision guide pin 2 includes a first insertion section and a first guide section. The first insertion section is used to be inserted into the through hole 15. The outer diameter of the first insertion section is smaller than the outer diameter of the first guide section and the end is chamfered. The surface of the first insertion section has a groove. The bottom surface of the groove is a plane parallel to the axis of the precision guide pin 2. The first insertion section and the first guide section are transitioned by a chamfer. Figure 3 There is an inclined cutting plane at the right end of the first guide section (so that the outer diameter of the cross section gradually decreases), and the cutting plane and the bottom surface of the groove are both located on the same side of the axis of the precision guide pin 2, which is convenient for inserting and pulling out the precision hole on the mounting edge of the turbine support. The outer diameter of the first guide section matches the inner diameter of the precision hole on the turbine support;

[0038] like Figure 3 The guide pin 3 includes a second insertion section and a second guide section. The second insertion section is used to be inserted into the through hole 15. The outer diameter of the second insertion section is smaller than the outer diameter of the second guide section and the end is chamfered. The second insertion section and the second guide section are transitioned by a chamfer. The surface of the second insertion section has a groove, and the bottom surface of the groove is a plane parallel to the axis of the guide pin 3. Figure 3 The right end of the second guide section has an inclined cutting plane (so that the outer diameter of the cross section gradually decreases), and the cutting plane and the bottom surface of the groove are both located on the same side of the axis of the guide pin 3, so as to facilitate insertion into the common hole on the mounting edge of the turbine support. The outer diameter of the second guide section matches the inner diameter of the common hole on the turbine support;

[0039] When the limiting pin 4 is inserted into the limiting hole 16, the end of the limiting pin 4 presses the bottom surface of the groove of the first insertion section and the second insertion section (such as Figure 3 The guide pins 2 and 3 are fixed to prevent them from rotating, and the cutting planes of the guide pins 3 and the precision guide pins 2 are uniformly oriented to the radial direction of the turbine support mounting edge. The cutting planes of the guide pins 3 and the precision guide pins 2 form a guide surface with an outer diameter from small to large, which retains sufficient operating space.

[0040] The opening of the through hole 15 is processed with chamfers, and the first insertion section and the second insertion section are both processed with chamfers to facilitate the insertion process. The through hole 15 is a through hole, so it also has an observation function.

[0041] The high-precision auxiliary installation tool is divided into two detachable parts (support 1 as one part, and the rest as another part), wherein the limit pin 4 (3 pieces) is installed on the support 1 (1 piece) to limit the precision guide pin 2 (1 piece) and the guide pin 3 (2 pieces) to prevent the precision guide pin 2 (1 piece) and the guide pin 3 (2 pieces) from rotating, so as to ensure that the cutting surfaces of the precision guide pin 2 and the guide pin 3 are facing the turbine support casing, and to ensure that there is enough space for installation and disassembly.

[0042] Turbine bearing installation method using the above tools:

[0043] Assuming that there are 35 threaded holes in the front mounting edge of the turbine support, of which 7 are precision holes, 3 sets of high-precision auxiliary installation tools are used at the same time, and the support 1 of the 3 sets of high-precision auxiliary installation tools is evenly installed on the rear mounting edge of the low-pressure turbine guide on the main engine (the main engine is the main part of the engine, and the turbine support is mainly installed on the main engine through the low-pressure turbine guide). On the one hand, the 3 sets of tools play the role of 3-point positioning planes, and on the other hand, too many tools will increase the installation time. Afterwards, 6 guide pins 3 are inserted into the support 1 to guide the 6 ordinary holes on the turbine support;

[0044] Then, insert three precision guide pins 2 into the through holes 15 of the support 1 from top to bottom to guide the three precision holes on the turbine support, and then insert nine limit pins 4 horizontally into the limit holes 16 on the support 1 to lock the precision guide pins 2 and the guide pins 3;

[0045] After completing the tool installation, the turbine bearing is vertically lifted by a crane. During the process, ensure that the precision hole on the turbine bearing matches the precision guide pin 2. The turbine bearing is slowly lowered under the guidance of the precision guide pin 2 until it fits with the rear mounting edge of the low-pressure turbine guide. Then, remove the precision guide pin 2 and guide pin 3 from the top (i.e., remove them from the top of the turbine bearing mounting edge), and then remove 1, thereby completing the guidance of the turbine bearing and achieving high-precision assembly of the turbine bearing.

[0046] 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. High-precision auxiliary installation tool for aircraft engine turbine support, characterized by: include, A support (1), wherein the support (1) is a fan-shaped structure with a central angle of less than 180°, and comprises a first fitting surface (11) for fitting the lower end surface of the rear mounting edge of a low-pressure turbine guide vane, and a second fitting surface (12) for fitting the protrusion on the circumferential outer surface of the low-pressure turbine guide vane, the first fitting surface (11) is provided with a through hole (15) penetrating the support (1), the support (1) is also provided with a limiting hole (16), and the limiting hole (16) is connected to the through hole (15); the cross-sectional shape of the support (1) is trapezoidal, and comprises an avoidance surface (13) and a weight-reducing conical surface (14), the weight-reducing conical surface (14) cooperates with the through hole (15) so that the center of gravity of the support (1) is close to the avoidance surface (13), the first fitting surface (11) serves as a longer bottom edge, and the second fitting surface (12) serves as a shorter top edge; A precision guide pin (2), the precision guide pin (2) comprising a first insertion section and a first guide section, the first insertion section being inserted into the through hole (15), the outer diameter of the first guide section being larger than the inner diameter of the through hole (15), and the outer diameter of the first guide section matching the inner diameter of the precision hole on the turbine support; A guide pin (3), the guide pin (3) comprising a second insertion section and a second guide section, the second insertion section being inserted into the through hole (15), the outer diameter of the second guide section being larger than the inner diameter of the through hole (15), and the outer diameter of the second guide section matching the inner diameter of a common hole on the turbine support; A limiting pin (4), when the limiting pin (4) is inserted into the limiting hole (16), the end of the limiting pin (4) is in close contact with the surface of the first insertion section and the surface of the second insertion section; A support (1) is provided with three through holes (15) and three limiting holes (16), wherein a central through hole (15) is used for a precision guide pin (2), and the through holes (15) on both sides are used for guide pins (3); The first guide section and the second guide section also include an outer diameter gradient section with a gradually decreasing outer diameter.

2. The high-precision auxiliary installation tool for aero-engine turbine bearing according to claim 1, characterized in that: The transition between the first insertion section and the first guide section is chamfered, the transition between the second insertion section and the second guide section is chamfered, and the through hole (15) is chamfered at the opening at one end of the first fitting surface (11).

3. The high-precision auxiliary installation tool for aero-engine turbine bearing according to claim 1, characterized in that: The ends of the first insertion section and the second insertion section inserted into the through hole (15) are both chamfered, and the surfaces of the first insertion section and the second insertion section include at least one plane.

4. A method for installing a turbine bearing using the high-precision auxiliary installation tool for an aircraft engine turbine bearing according to claim 1, Features: include, Step 1: according to the number of precision holes and common holes on the front mounting edge of the turbine support, the number of sets of high-precision auxiliary mounting tools for the aircraft engine turbine support is determined, and the supports (1) in the plurality of sets of auxiliary mounting tools are evenly distributed along the radial direction of the low-pressure turbine guide and mounted on the outer side of the circumferential surface of the low-pressure turbine guide on the main engine, and the first fitting surface (11) is in close contact with the lower end surface of the rear mounting edge of the low-pressure turbine guide, and the second fitting surface (12) is in close contact with the raised end surface on the circumferential outer surface of the low-pressure turbine guide; Step 2: insert the guide pin (3) and the precision guide pin (2) into the through hole (15) from top to bottom, and then insert the limit pin (4) into the limit hole (16) of the support (1) to lock the guide pin (3) and the precision guide pin (2); Step three: vertically hoist the turbine support by means of a crane. During the process, ensure that the precision hole on the turbine support matches the precision guide pin (2). The turbine support is slowly lowered under the guidance of the precision guide pin (2) until it fits with the rear mounting edge of the low-pressure turbine guide. Then, remove the precision guide pin (2) and guide pin (3) from above in turn, and then remove the support (1) to complete the guided assembly of the turbine support.

5. The turbine support installation method according to claim 4, characterized in that: In the step 1, the number of sets of high-precision auxiliary installation tools for aircraft engine turbine supports is 3 sets.

6. The turbine support installation method according to claim 4, characterized in that: In the second step, a precision guide pin (2) having a first guide section with an outer diameter gradient section and a guide pin (3) having a second guide section with an outer diameter gradient section are used.

Images