A device and method for measuring axial movement of an aeroengine bearing

Abstract

This application belongs to the field of aero-engine technology, and specifically relates to a device and method for measuring the axial movement of an aero-engine bearing, including a push rod and a base; wherein, the upper end face of the base has a platform supporting a two-point stator, the platform has an internal threaded hole, the push rod has an external thread that mates with the internal threaded hole and a torque-applying wrench, the push rod has an upper pressure plate and a lower pressure plate, and the push rod moves axially under the relative rotation of the internal threaded hole and the external thread by applying torque through the wrench, and multiple dial gauges for measuring the axial displacement of the two-point component rotor are installed on the base, and the two-point rotor is lifted by setting upper and lower limit torque values ​​during measurement, which improves the stability of force application and avoids the risk of elastic deformation of the two-point component due to large tension or uneven force application during the lifting process of traditional measurement process, thereby reducing the risk of damage to engine components during the process.

Description

Technical Field

[0001] This application belongs to the field of aero-engine technology, and specifically relates to a device and method for measuring the axial movement of aero-engine bearings. Background Technology

[0002] The design and control of the rotor-stator clearance in an aero-engine directly determines its performance. In a certain type of aero-engine, the low-pressure turbine rotor is connected to a two-point support assembly. The rotor of this assembly is connected to the stator casing via ball bearings. The axial clearance of these ball bearings directly affects the rotor-stator clearance during engine testing. During aero-engine assembly and production, the axial clearance of the ball bearings must be measured, providing data guidance for real-time monitoring and control of the rotor-stator clearance.

[0003] Currently, the clearance measurement process for the ball bearings in the two-point assembly is carried out under the condition of the engine assembly. Figure 4 In the rotor's natural state, the bearing movement is eliminated by moving it forward. A dial indicator is then placed in contact with the front end face of the two-point rotor and zeroed. Next, a crane scale is used to lift the rotor assembly backward to eliminate the bearing movement. By comparing the difference in dial indicator readings between the low-pressure rotor's natural state and the lifted state, the axial movement of the bearings in the two-point assembly can be calculated.

[0004] The main problems with existing measurement methods are:

[0005] 1. When a crane scale is used to lift a rotor, once the scale reading reaches the rotor's mass, the lifting continues to eliminate bearing movement. However, controlling the uniformity of force applied by the crane scale during lifting is difficult, and the scale reading is prone to sudden changes, resulting in poor operational stability. There is a risk that excessive instantaneous lifting force may cause elastic deformation of the two-point support assembly, leading to measurement deviations.

[0006] 2. It is difficult to ensure that the hoisting rope is completely aligned with the engine axis during hoisting, which can easily pull the rotor off-center, resulting in deviations in the measured values. Figure 5 As shown, the measurement deviation value Δ=Rtanф, where R is the distance from the rotor center to the measurement end face, which is a constant. Therefore, the degree of deviation of the engine shaft during hoisting determines the magnitude of the deviation, and the greater the degree of deviation, the greater the measurement deviation.

[0007] 3. The measurement of the axial movement of the two support points is carried out in the engine transfer state. If the measurement result is out of tolerance, the low-pressure turbine rotor and the two support point assembly must be completely disassembled and the two support point bearings must be reassembled to eliminate the risk of out of tolerance. This prolongs the assembly cycle and results in extremely low assembly efficiency. Summary of the Invention

[0008] To address the aforementioned problems, this application provides an axial movement measuring device for an aero-engine bearing, used to measure the axial movement of a two-point assembly bearing. The two-point assembly includes: a two-point assembly rotor, two-point stators, and bearings. The two-point assembly rotor is fitted within a central hole in the two-point stators via the bearings. The measuring device includes a push rod and a base. The upper surface of the base has a platform supporting the two-point stators, and the platform has a circular groove at its center to accommodate the two-point assembly rotor. The bottom of the groove has an internally threaded hole. The push rod... The device has an external thread that mates with the internal threaded hole and a wrench for applying torque. An upper pressure plate and a lower pressure plate are located at the middle position of the push rod. The upper and lower pressure plates are positioned on either side of a stop on the inner wall of the two-point assembly rotor, and they overlap with the stop. By applying torque with the wrench, the push rod moves axially under the relative rotation of the internal threaded hole and the external thread. The push rod, through the moving upper and lower pressure plates, drives the two-point assembly rotor to move axially. Multiple dial indicators for measuring the axial displacement of the two-point assembly rotor are mounted on the base.

[0009] Preferably, an anti-rotation shaft is installed in the circular groove, the anti-rotation shaft is sleeved inside the rotor of the two-point assembly, and the anti-rotation shaft has a through hole through which the push rod passes.

[0010] Preferably, the platform has a stop that overlaps with the two-point stator, and the position of the two-point stator is determined by the overlap of the platform's stop.

[0011] Preferably, the lower pressure plate includes: a base plate, balls, and a cover plate. The base plate is fixed on the top rod. The base plate has an annular stepped surface at the contact point with the stop of the two-point assembly rotor. A cover plate is arranged on the stepped surface that directly contacts the stop of the two-point assembly rotor. The balls are circumferentially distributed between the stepped surface and the cover plate by a cage.

[0012] Preferably, a lubricant is applied between the upper pressure plate and the stop of the two-point assembly rotor, and a lubricant is applied between the lower pressure plate and the stop of the two-point assembly rotor.

[0013] Preferably, the top rod has a limiting shoulder, and the upper pressure plate is fixed by the limiting shoulder and the nut.

[0014] Preferably, the wrench is a digital display torque limiter wrench.

[0015] A method for measuring the axial movement of an aero-engine bearing, using the aforementioned aero-engine bearing axial movement measuring device:

[0016] Step 1: Install the two-point assembly onto the measuring device;

[0017] Step 2: Tighten the wrench to turn the push rod downwards. At this time, the upper pressure plate presses down on the two-point rotor, causing the two-point rotor assembly to move downwards. When the applied torque reaches the minimum tightening torque T... min Then continue to apply torque overload, and the final torque shall not exceed the maximum tightening torque T. max At this point, the rotor of the two-point assembly is brought into contact with the dial indicator's measuring contacts, and the dial indicator reading is returned to zero.

[0018] Step 3: Tighten the wrench in the reverse direction to rotate the push rod upwards. After the lower pressure plate is in contact with the two-point rotor, continue to rotate the torque-limiting wrench until the applied torque reaches the maximum tightening torque T. max Stop after that; record the percentage value.

[0019] Step 4: Organize the percentage readings and use the organized percentage readings as the measured value of the bearing axial clearance.

[0020] Preferably, the minimum turning torque T min Calculated using the following formula:

[0021] T min =KFD;

[0022] Where K is the tightening torque coefficient; F is the resultant force of the measured load required by the bearing design and the force to overcome the weight of the rotor of the two-point assembly; and D is the nominal diameter of the push rod thread.

[0023] Preferably, the maximum turning torque T max The maximum turning torque T is calculated using the following formula: When the stator housing at the two fulcrums of the wrench undergoes a predetermined degree of deformation during tightening, the torque value at this point is taken as the maximum tightening torque T. max .

[0024] The advantages of this application include:

[0025] 1. The upper and lower limits of the tightening torque are specified, which improves the stability of the force application and avoids the risk of elastic deformation of the two-point assembly due to large tension or uneven force application during the lifting process of traditional measurement process, thereby reducing the risk of damage to engine parts during the process.

[0026] 2. During measurement, the upper and lower pressure plates of the measuring instrument cooperate with the rotor of the two-support assembly through the stop, ensuring the radial centering of the rotor during the measurement process and reducing the risk of deviation in the measured value caused by the pull during the traditional measurement process.

[0027] 3. This measuring tool can directly measure the axial clearance of the bearing in the two-point assembly without the low-pressure turbine rotor installed. It can identify the risk of bearing movement deviation in the two-point assembly state, reducing the risk of disassembly and rework of parts due to bearing clearance measurement deviation during transfer and improving assembly efficiency. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the installation of the bearing axial movement measuring device and the two-point support assembly;

[0029] Figure 2 This is a schematic diagram of a bearing axial movement measuring device;

[0030] Figure 3 yes Figure 2 A partial enlarged view of area A in the schematic diagram of the bearing axial movement measuring device;

[0031] Figure 4 This is a schematic diagram of the measurement process in the prior art;

[0032] Figure 5 This is a schematic diagram illustrating the generation of measurement deviations in existing technologies;

[0033] Figure 6 This is a flowchart for measuring the axial movement of a traditional bearing.

[0034] Figure 7 This is a flowchart of the bearing axial movement measurement process in this application. Detailed Implementation

[0035] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below with reference to the accompanying drawings. In the drawings, the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The described embodiments are only some, not all, of the embodiments of this application. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application. The embodiments of this application will be described in detail below with reference to the accompanying drawings.

[0036] like Figures 1-3As shown, an axial movement measuring device for an aero-engine bearing is used to measure the axial movement of a two-point assembly bearing. The two-point assembly includes a two-point assembly rotor 3, a two-point stator 2, and a bearing 5. The two-point assembly rotor 3 is fitted into a central hole in the two-point stator 2 via the bearing 5. The measuring device 1 is characterized by comprising a push rod 4 and a base. The upper surface of the base has a platform supporting the two-point stator 2. A circular groove for accommodating the two-point assembly rotor 3 is located at the center of the platform. The bottom of the groove has an internal threaded hole. The push rod 4 has an external thread that mates with the internal threaded hole and a torque-applying wrench. 13. The top rod 4 has an upper pressure plate 9 and a lower pressure plate 10 at its middle position. The upper pressure plate 9 and the lower pressure plate 10 are located on both sides of the stop on the inner wall of the two-point assembly rotor 3. The upper pressure plate 9 and the lower pressure plate 10 are engaged with the stop. When torque is applied by the wrench 13, the top rod 4 moves axially under the relative rotation of the internal thread hole and the external thread. The top rod 4 drives the two-point assembly rotor 3 to move axially through the moving upper pressure plate 9 and the lower pressure plate 10. Multiple dial indicators 11 for measuring the axial displacement of the two-point assembly rotor 3 are installed on the base. The dial indicators 11 are mounted on a frame, which is fixed to the base by screws and locating pins. The dial indicators 11 are fixed to the frame by cross-head screws. The threaded section of the push rod is threaded with the base. The push rod is screwed up and down by the wrench 13, which drives the upper and lower pressure plates to rise and fall, respectively realizing the process of eliminating the movement of the bearing in the measuring instrument. The upper and lower pressure plates are fitted with the two-point rotor with a small clearance through the stop, realizing the radial centering of the two-point rotor during measurement.

[0037] In some alternative embodiments, an anti-rotation shaft 12 is installed in the circular groove, the anti-rotation shaft 12 is sleeved inside the two-point assembly rotor 3, and the anti-rotation shaft 12 has a through hole through which the push rod 4 passes.

[0038] In some alternative embodiments, the platform has a stop that overlaps with the two-point stator 2. The position of the two-point stator 2 is determined by the overlap of the platform's stop, and the two-point assembly stator 2 and the base are centered by the cooperation of the stop.

[0039] In some alternative embodiments, when the axial movement of the bearing exceeds a certain level, while the lower pressure plate 10 lifts the two-point assembly rotor 3, the lower pressure plate 10 rotates with the top rod. In order to eliminate the friction between the rotating lower pressure plate 10 and the two-point assembly rotor 3, a lower pressure plate 10 with ball bearings is provided. Specifically, the lower pressure plate 10 includes: a base plate, ball bearings, and a cover plate. The base plate is fixed on the top rod 4. The contact area between the base plate and the stop of the two-point assembly rotor 3 has an annular stepped surface. A cover plate that directly contacts the stop of the two-point assembly rotor 3 is arranged on the stepped surface. The ball bearings are circumferentially distributed between the stepped surface and the cover plate through a cage.

[0040] Alternatively, when the axial movement of the bearing is small, the frictional force between the rotating lower pressure plate 10 and the two-point assembly rotor 3 that needs to be eliminated can be resolved by applying lubricant between the upper pressure plate 9 and the stop of the two-point assembly rotor 3.

[0041] In some alternative embodiments, the top rod 4 has a limiting shoulder, and the upper pressure plate 9 is fixed by the limiting shoulder and a nut.

[0042] In some alternative implementations, the wrench 13 is a digitally displayed force-limiting wrench.

[0043] A method for measuring the axial movement of an aero-engine bearing, using the aforementioned aero-engine bearing axial movement measuring device: before measurement, the lower and upper limits of the applied torque are determined, including: a minimum tightening torque T. min Maximum twisting torque T max Minimum turning torque T min Calculated using the following formula:

[0044] T min =KFD;

[0045] Where K is the tightening torque coefficient; F is the resultant force of the measured load required by the bearing design and the force to overcome the gravity of the rotor 3 of the two-point assembly; D is the nominal diameter of the thread of the push rod 4, and the maximum tightening torque T is... max The maximum turning torque T is calculated using the following formula: When the housing of the two-point stator 2 of the wrench 13 undergoes a preset degree of deformation during turning, the torque value at this time is taken as the maximum turning torque T. max .

[0046] Step 1: As Figure 3 As shown, the two-point assembly is mounted onto the measuring device, and if necessary, the stator of the two-point assembly is fixed to the base using process bolts.

[0047] Step 2: Tighten wrench 13 to turn push rod 4 downwards. At this time, upper pressure plate 9 presses down on the two-point rotor, causing the two-point assembly rotor 3 to move downwards. When the applied torque reaches the minimum tightening torque T... min Then stop, at this time bring the rotor 3 of the two-point assembly into contact with the measuring contact of the dial indicator 11, and return the reading of the dial indicator 11 to zero;

[0048] Step 3: Twist the wrench 13 in the reverse direction to make the push rod 4 rotate upward. After the lower pressure plate 10 is in contact with the two-point rotor, continue to rotate the force-limiting wrench 13 until the applied torque reaches the maximum tightening torque T. max Stop after that; record the reading on dial indicator 11;

[0049] Step 4: The dial indicator 11 includes multiple dial indicators. Calculate the average value of the readings of multiple dial indicators, which is used as the measured value of the bearing axial clearance. Use the sorted dial indicator 11 reading as the measured value of the bearing axial clearance.

[0050] like Figures 5-6 As shown, before the measurement process was improved, the first step in engine assembly was to install the two-point assembly, the second step was to install the low-vortex rotor, and the third step was to measure the movement of the two-point assembly. When the movement did not meet the design value, the assembly was suspended, and the two-point assembly and the low-vortex rotor assembly were disassembled and the two-point assembly was reassembled.

[0051] like Figure 7 As shown, after improving the measurement process, the movement of the two-point assembly can be measured before the assembly is installed. When the movement does not meet the design value, the two-point assembly can be adjusted directly without disassembling the two-point assembly and the low-vortex rotor assembly. This reduces the risk of disassembly and rework of parts due to bearing clearance measurement errors during assembly and improves assembly efficiency.

[0052] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A method for measuring the axial movement of an aero-engine bearing, characterized in that: An aero-engine bearing axial movement measuring device is used to measure the axial movement of a two-point assembly bearing. The two-point assembly includes a two-point assembly rotor (3), a two-point stator (2), and a bearing (5). The two-point assembly rotor (3) is fitted into the center hole of the two-point stator (2) through the bearing (5). The measuring device (1) includes a push rod (4) and a base. The upper end face of the base has a platform supporting the two-point stator (2). The center of the platform has a circular groove for accommodating the two-point assembly rotor (3). The bottom of the circular groove has an internal thread hole. The push rod (4) has an external thread that mates with the internal thread hole and a wrench (13) for applying torque. The middle position of the push rod (4) has an upper pressure plate (9) and a lower pressure plate (10). The upper pressure plate (9) and the lower pressure plate (10) are located on the inner wall of the two-point assembly rotor (3). The upper pressure plate (9) and the lower pressure plate (10) are engaged with the stop on both sides of the stop. The torque is applied by the wrench (13), and the push rod (4) moves axially under the relative rotation of the internal thread hole and the external thread. The push rod (4) drives the two-point assembly rotor (3) to move axially through the following upper pressure plate (9) and lower pressure plate (10). Multiple dial gauges (11) for measuring the axial displacement of the two-point assembly rotor (3) are installed on the base. The wrench (13) is a digital display limit wrench. The lower pressure plate (10) includes: a base plate, balls and a cover plate. The base plate is fixed on the push rod (4). The base plate has an annular stepped surface at the contact point between the base plate and the stop of the two-point assembly rotor (3). The cover plate is arranged on the stepped surface to directly contact the stop of the two-point assembly rotor (3). The balls are circumferentially distributed between the stepped surface and the cover plate through the cage. The method includes: Step 1: Install the two-point assembly onto the measuring device; Step 2: Tighten the wrench (13) to make the push rod (4) turn downwards. At this time, the upper pressure plate (9) presses down on the two-point rotor, causing the two-point assembly rotor (3) to move downwards. When the applied torque reaches the minimum tightening torque T min Then continue to apply torque overload, and the final torque shall not exceed the maximum tightening torque T. max At this time, the rotor (3) of the two-point assembly is brought into contact with the measuring contact of the dial indicator (11), and the reading of the dial indicator (11) is returned to zero. Step 3: Twist the wrench (13) in the reverse direction to make the push rod (4) rotate upward. After the lower pressure plate (10) is in contact with the two-point rotor, continue to rotate the force-limiting wrench (13) until the applied torque reaches the maximum turning torque T. max Then stop; record the reading of the dial indicator (11); Step 4: Organize the dial indicator (11) reading and use the organized dial indicator (11) reading as the measured value of the bearing axial clearance; Minimum turning torque T min Calculated using the following formula: T min =KFD; Wherein, K is the tightening torque coefficient; F is the resultant force of the measured load required by the bearing design and the force to overcome the gravity of the rotor (3) of the two-point assembly; and D is the nominal diameter of the thread of the push rod (4).

2. The method for measuring the axial movement of an aero-engine bearing as described in claim 1, characterized in that, The anti-rotation shaft (12) is installed in the circular groove of the aero-engine bearing axial movement measuring device. The anti-rotation shaft (12) is sleeved inside the rotor (3) of the two-point assembly. The anti-rotation shaft (12) has a through hole through which the push rod (4) passes.

3. The method for measuring the axial movement of an aero-engine bearing as described in claim 1, characterized in that, The platform of the aero-engine bearing axial movement measuring device has a stop that overlaps with the two-point stator (2), and the position of the two-point stator (2) is determined by the overlap of the platform's stop.

4. The method for measuring the axial movement of an aero-engine bearing as described in claim 1, characterized in that, In the aero-engine bearing axial movement measuring device, lubricant is applied between the upper pressure plate (9) and the stop of the two-point assembly rotor (3), and lubricant is applied between the lower pressure plate (10) and the stop of the two-point assembly rotor (3).

5. The method for measuring the axial movement of an aero-engine bearing as described in claim 1, characterized in that, The top rod (4) of the aero-engine bearing axial movement measuring device has a limiting shoulder, and the upper pressure plate (9) is fixed by the limiting shoulder and the nut.

6. The method for measuring the axial movement of an aero-engine bearing as described in claim 1, characterized in that, Maximum twisting torque T max The determination method is as follows: when the housing of the two-point stator (2) of the wrench (13) undergoes a preset degree of deformation during the tightening, the torque value at this time is taken as the maximum tightening torque T. max .

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