Rotor axial dimension measuring tool and method

Abstract

Provided are a rotor-stator axial dimension measuring tool and a rotor-stator axial dimension measuring method. The rotor-stator axial dimension is the axial distance from the rear mounting edge of an intermediate casing to a centering boss. The tool comprises an external support frame for abutting the rear mounting edge of the intermediate casing, and a core rod that extends into the shaft cavity of the rotor-stator and has a tail end for abutting the centering boss. The core rod is movably arranged on the external support frame and comprises a measuring reference surface near the front end side. The rotor-stator axial dimension measuring tool and method can simplify the process of measuring the axial dimension of a low-pressure rotor-stator.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of engine assembly, in particular to the field of measurement in the assembly stage. BACKGROUND

[0002] An aero-engine has a complex structure and a large number of parts. The engine body can be divided into a fan case unit, a core engine unit and a low-pressure turbine unit according to unit bodies. The first and second supporting points of the unit bodies generally have a clearance and can produce axial movement. In order to prevent the rotor and stator blades from being scratched during the test run, an adjusting pad is selected and matched at the rotor to adjust the axial clearance before and after the rotor disc. The size calculation of the adjusting pad is one of the work focuses in the assembly stage of the aero-engine. An adjusting pad with a suitable thickness can ensure the performance and safety reliability of the engine. However, the traditional measurement method needs more steps and is relatively complex to operate.

[0003] Therefore, how to quickly and accurately measure and calculate the low-pressure rotor-stator axial size is important for subsequent selection and matching of the adjusting pad and butt joint of the large part. SUMMARY

[0004] The purpose of the present application is to provide a rotor-stator axial size measurement tool that can simplify the low-pressure rotor-stator axial size measurement process.

[0005] The rotor-stator axial size measurement tool for measuring the rotor-stator axial size includes a rotor-stator, an external support frame and a core rod. The rotor-stator includes a middle casing rear mounting edge at the end of the middle casing and a centering boss on the shaft. The rotor-stator axial size is the axial distance from the middle casing rear mounting edge to the centering boss. The external support frame is used to abut against the middle casing rear mounting edge. The core rod extends into the shaft cavity of the rotor-stator, and the tail end of the core rod is used to abut against the centering boss. The core rod is movably arranged on the external support frame, and the measurement reference surface is arranged close to the front end side.

[0006] In one or more embodiments, the centering boss is arranged on the fan shaft, and the tail end of the core rod is further provided with a spline for matching with the spline on the fan shaft.

[0007] In one or more embodiments, the tool further includes a pressing bolt connected to the front end of the core rod, and the pressing bolt is used to push the core rod to move axially.

[0008] In one or more embodiments, the tool further includes a force sensor arranged between the pressing bolt and the core rod.

[0009] In one or more embodiments, the external support frame is detachably fixed on the middle casing rear mounting edge by a bolt fastener.

[0010] Another object of the present application is to provide a rotor axial dimension measurement method using the above rotor axial dimension measurement tool, which comprises the following steps: abutting the external support frame against the rear mounting edge of the intermediate casing; extending the mandrel into the axial cavity of the rotor and abutting the tail end of the mandrel against the centering boss; applying an axial force to the mandrel to push the fulcrum bearing to the front pushing state; measuring the distance from the measurement reference surface of the mandrel to the rear mounting edge of the intermediate casing to obtain the length from the measurement reference surface of the mandrel to the tail end; and finding the bearing play of the fulcrum bearing.

[0011] The above rotor axial dimension measurement tool and method do not need to separately measure the axial dimensions of the intermediate casing and the first and second fulcrum bearings, and after the first and second fulcrum bearings are directly pushed to the front pushing position by the mandrel, the axial dimension of the low-pressure rotor is directly measured, which can simplify the measurement process, reduce the measurement difficulty, and thus improve the engine assembly efficiency and quality and provide quick guidance for the selection of adjustment pads. BRIEF DESCRIPTION OF DRAWINGS

[0012] The above and other features, properties, and advantages of the present application will become more apparent by describing in detail the following embodiments with reference to the accompanying drawings and examples, in which:

[0013] Figure 1 is a simplified diagram of an engine structure;

[0014] Figure 2 is a schematic diagram of the measurement principle of an existing low-pressure rotor stator;

[0015] Figure 3 is a schematic diagram of the cooperation between the rotor axial dimension measurement tool and the rotor;

[0016] Figures 4A-4B is a schematic diagram of the mandrel;

[0017] Figures 5A-5B is a schematic diagram of the external support frame;

[0018] Figure 6 is a flowchart of the rotor axial dimension measurement method.

[0019] SYMBOL EXPLANATION

[0020] 1 fan blade

[0021] 2 fan casing

[0022] 3 intermediate casing

[0023] 4 core machine rotor

[0024] 5 core machine stator

[0025] 6 low-pressure rotor

[0026] 7 low-pressure turbine stator casing

[0027] 8. Turbine rear casing

[0028] 9-stage inter-stage casing

[0029] 10. Boost stage

[0030] 11. Rear mounting edge of intermediate housing

[0031] 12 Adjustment Pads

[0032] 13. Locating shoulder

[0033] 14 Centering Boss

[0034] 16 Fan Shaft

[0035] 31 External support frame

[0036] 32 mandrels

[0037] 33 Bolts and fasteners

[0038] 34. Tightening bolts

[0039] 35 Force Sensor

[0040] 322 spline

[0041] 323 Measurement datum Detailed Implementation

[0042] The present invention will be further described below with reference to specific embodiments and accompanying drawings. More details are set forth in the following description in order to provide a full understanding of the present invention. However, the present invention can obviously be implemented in many other ways different from those described herein. Those skilled in the art can make similar extensions and derivations based on actual application situations without departing from the spirit of the present invention. Therefore, the scope of protection of the present invention should not be limited by the content of this specific embodiment.

[0043] It should be noted that these and other accompanying drawings are merely examples and are not drawn to scale, and should not be construed as limiting the scope of protection of the present invention.

[0044] Figure 1 The simplified structure of an aero-engine is shown, including fan blades 1, fan casing 2, intermediate casing 3, core engine rotor 4, core engine stator 5, low-pressure turbine rotor 6, low-pressure turbine stator casing 7, turbine rear casing 8, interstage casing 9, booster stage 10, and fan shaft 16. It also includes five pivot points A, B, C, D, and E, where the first pivot point A and the second pivot point B are generally ball bearings with axial clearance, which can produce axial micro-movements.

[0045] The connection between the core stator 5 and the intermediate casing 3 is the rear mounting edge 11 of the intermediate casing, which abuts against the front stator mounting edge, and the fan shaft 16 has a positioning shaft shoulder 13 and a centering boss 14.

[0046] In the first fulcrum A and the second fulcrum B, an adjusting pad 12 needs to be arranged to adjust the axial gap between the front disc of the rotor disc and the rear disc.

[0047] The conventional measurement method of the axial size of the low-pressure rotor stator is as follows.

[0048] As shown in Figure 2 First, the axial size L2 of the intermediate casing unit body is measured, which is the distance from the rear mounting edge 11 of the intermediate casing to the front mounting edge of the intermediate casing, and the rear mounting edge abuts against the rear mounting edge N of the first and second fulcrums. Since the unit body size of the intermediate casing 3 is large, high requirements are put forward for the specifications of the three-coordinate measuring equipment, and high requirements are put forward for turning, hoisting, measuring, etc.

[0049] Then, the axial distance VM from the rear mounting edge N of the first and second fulcrums to the positioning shaft shoulder 13 is measured when the first and second fulcrum bearings are in the front pushing state.

[0050] Then, the axial size Lc of the centering boss 14 on the fan shaft 16 to the positioning shaft shoulder 13 of the first and second fulcrums is obtained. Since the distance from the fan shaft centering boss 14 to the rear mounting edge N of the first and second fulcrums is far, and the fan shaft diameter is small, it is not conducive to direct measurement by a general measuring tool.

[0051] Then, the bearing clearance ZY2 of the ball bearing of the second fulcrum B is found.

[0052] According to the formula, the axial size of the low-pressure rotor stator, that is, the axial distance L1 from the rear mounting edge of the intermediate casing, that is, the front stator mounting edge to the centering boss 14 at the theoretical center position of the second fulcrum bearing, is obtained, that is, L1=L2+VM-Lc-(ZY2 / 2).

[0053] It can be seen that the above method has many size chains and complicated measurement, and one data error will affect the entire calculation result.

[0054] The rotor stator axial size measurement method and tool described in the disclosure can effectively reduce the intermediate process, simplify the current complex measurement and calculation process, greatly reduce the quality risk link, and avoid the inaccurate calculation result caused by tolerance accumulation.

[0055] Referring to Figure 3As shown, the tooling includes an external support frame 31 and a core rod 32, the external support frame 31 abuts against the intermediate casing rear mounting edge 11, such as the external support frame 31 is fixed on the intermediate casing rear mounting edge 11 of the intermediate casing 3 through bolt fasteners 33. The core rod 32 extends into the rotor-stator shaft cavity to achieve axial positioning and cylindrical centering. The core rod 32 is used to push the bearings of the one-two support point axially to make the bearings of the one-two support point in the front pushing state, so as to carry out subsequent measurement.

[0056] As shown, the tail end 321 of the core rod 32 abuts against the centering boss 14. Preferably, the tail end 321 of the core rod 32 is provided with splines 322, which are in contact with the splines on the support 16 to complete the fixation of the core rod. The core rod 32 is movably arranged on the external support frame 31 and also includes a measurement reference surface 323 close to the front end side. Figures 4A-4B

[0057] The core rod 32 has an axial distance Lcore, which is the axial length from the measurement reference surface 323 to the tail end 321.

[0058] The tooling also includes a compression bolt 34 and a force sensor 35, the compression bolt 34 passes through the threaded hole 318 on the external support frame 31 and is connected with the force sensor 35, the front end of the core rod 32 is located in the positioning cavity 319, and the force sensor 35 is located between the core rod 32 and the compression bolt 34.

[0059] As shown, the required axial force is applied to the force sensor 35 through the compression bolt 34 to push the core rod 32 to move axially, and then the tail end 321 of the core rod 32 applies an axial force to the centering boss 14, so as to make the one-two support point ball bearing axially move forward and be in the front pushing state, which is the premise of accurate measurement of the axial size L1. Figures 5A-5B Generally speaking, it is difficult to push the bearing to move when the axial force is small, and it will also cause damage to engine parts when the axial force is too large. Therefore, when the axial force of the compression bolt 34 displayed by the force sensor 35 is within a suitable range, it can be considered that the one-two support point ball bearing has axial displacement at this time. The range of force is determined according to different engine specifications, such as in an embodiment, the axial force of the compression bolt 34 within the range of 1000-1600N is regarded as an effective pushing force. In this way, the one-two support point unit body is simply and conveniently pushed to the front pushing limit measurement position in the assembled state, so that the axial assembly size control of the intermediate casing and the one-two support point is more accurate.

[0060] At this time, the axial distance between the intermediate casing rear mounting edge 11 and the measurement reference surface 323 of the core rod 32 is measured using a ruler, depth gauge and other tools, and is recorded as Lmea. Lmea is located outside the engine shaft cavity, so it can be directly measured using a ruler, depth gauge and other tools.

[0061] ​​

[0062] Thus, the axial dimension calculation formula between the intermediate casing rear mounting edge 11 of the intermediate casing 3 and the centering boss 14 of the one-two support low-pressure rotor is simplified to L1=Lmeas+Lcore-(ZY2 / 2).

[0063] In this way, the axial dimension of the intermediate casing and the one-two support does not need to be measured separately before assembly, and the one-two support is directly assembled to the intermediate casing, reducing the measurement and calculation process. Instead, the axial dimension of the low-pressure rotor is directly measured by the axial distance Lmeas between the core rod 32 and the measuring reference surface 323 of the intermediate casing rear mounting edge 11 to the core rod 32, breaking the current complex dimension chain calculation method, reducing the measurement or copying process of multiple dimensions, reducing the risk link, and providing the possibility of quickly obtaining the appropriate low-pressure adjustment pad.

[0064] In addition, the use of the core rod 32 to internally push the bearing of the one-two support forward is more convenient than externally applying force to the unit body to make the bearing reach the forward state, and can also ensure that the bearing reaches the forward state, significantly reducing the influence of the forward state on measurement errors.

[0065] In combination with the introduction of the above-mentioned rotor axial dimension measurement tool, a rotor axial dimension measurement method can be connected, which includes the following steps: abutting the external support frame against the intermediate casing rear mounting edge; extending the core rod into the shaft cavity of the rotor and abutting the tail end of the core rod against the centering boss; applying an axial force to the core rod to push the bearing of the one-two support to a forward state; measuring the distance from the measuring reference surface of the core rod to the intermediate casing rear mounting edge to obtain the length from the measuring reference surface of the core rod to the tail end; and finding the bearing clearance of the support bearing.

[0066] Finally, the axial distance L1 from the intermediate casing rear mounting edge to the centering boss is directly obtained by the formula L1=Lmeas+Lcore-(ZY2 / 2).

[0067] The above-mentioned axial dimension measurement method is simple to operate, directly pushes the bearing forward by the internal core rod, uses a handheld general measuring tool for measurement, does not need to rely on complex equipment such as a three-coordinate device, can achieve the effect of axial assembly dimension error control, can shorten the dimension chain calculation, and greatly reduces the difficulty of dimension calculation.

[0068] The present application uses specific words to describe the embodiments of the present application. As "one embodiment", "an embodiment", and / or "some embodiments" means a certain feature, structure or characteristic related to at least one embodiment of the present application. Therefore, it should be emphasized and noted that the "one embodiment" or "one alternative embodiment" mentioned in different places in the specification does not necessarily refer to the same embodiment. In addition, certain features, structures or characteristics in one or more embodiments of the present application can be properly combined.

[0069] Although the present application has been disclosed in its preferred embodiments with reference to the accompanying drawings, it is not intended to limit the present application thereto, and any person skilled in the art can make possible changes and modifications without departing from the spirit and scope of the present application. Therefore, any modification, equivalent change and modification made to the above embodiments according to the technical essence of the present application without departing from the technical solutions of the present application, all fall within the protection scope defined by the claims of the present application.

Claims

1. A fixture for measuring the axial dimension of a rotor-stator, used to measure the axial dimension of a rotor-stator, the rotor-stator including an intermediate housing rear mounting edge located at the end of an intermediate housing and a centering boss located on a shaft, wherein the axial dimension of the rotor-stator is the axial distance from the intermediate housing rear mounting edge to the centering boss, and the aero-engine also includes a support point, at least part of which is a ball bearing, characterized in that, The tooling includes: An external support frame is provided to abut against the rear mounting edge of the intermediate housing; The mandrel extends into the shaft cavity of the rotor-stator, and its tail end is used to abut against the centering boss. The tail end of the mandrel is configured to apply axial force to the centering boss, thereby causing the ball bearing to move axially forward and be in a forward-pushing state. The mandrel is movably mounted on the external support frame and also includes a measuring calibrating surface near the front end.

2. The axial dimension measuring fixture for a rotor-stator as described in claim 1, characterized in that, The centering boss is mounted on the fan shaft, and the tail end of the mandrel is also provided with a spline for engaging with the spline on the fan shaft.

3. The axial dimension measuring fixture for a rotor-stator as described in claim 1, characterized in that, The tooling also includes a clamping bolt connected to the front end of the mandrel, the clamping bolt being used to push the mandrel axially.

4. The axial dimension measuring fixture for a rotor-stator as described in claim 3, characterized in that, The tooling also includes a force sensor disposed between the clamping bolt and the mandrel.

5. The axial dimension measuring fixture for a rotor-stator as described in claim 1, characterized in that, The external support frame is detachably fixed to the rear mounting side of the intermediate housing by bolt fasteners.

6. A method for measuring the axial dimension of a rotor-stator, characterized in that, The method of measuring the axial dimension of a rotor-stator using the tooling described in any one of claims 1-5 includes the following steps: The external support frame is abutted against the rear mounting edge of the intermediate housing; Insert the mandrel into the shaft cavity of the rotor-stator and make the tail end of the mandrel abut against the centering boss; An axial force is applied to the mandrel, pushing the fulcrum bearing to the forward position; The distance from the measuring datum plane of the mandrel to the rear mounting edge of the intermediate housing is measured to obtain the length from the measuring datum plane of the mandrel to its tail end. Locate the bearing clearance of the pivot bearing.

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