Calibration method and system of throat area detection device

Abstract

The invention discloses a calibration method and system of a throat area detection device. The calibration method comprises the following steps: manufacturing a standard sample piece, wherein the standard sample piece comprises a guider sample piece and a standard mounting disc; mounting the standard mounting disc on a rotary table of the detection device; the throat area S1 of the guider sample piece is measured at the position P1; the throat area Sn of the guider sample piece is measured at the position Pn; whether the error between the S1 and the Sn exceeds a first preset threshold value or not is determined, if yes, the detection device is checked, and the areas of the guider sample piece at all the radial positions are the same. The calibration method further comprises the steps that the average value Svt1 of the throat area of the guider sample piece measured at the time t1 is determined; determining the throat area Svtm of the guider sample piece measured at the time tm different from t1; and determining whether the error between the Svt1 and the Svtm exceeds a second predetermined threshold, and if so, checking the detection device. The invention further discloses a corresponding calibration system.

Description

Technical Field

[0001] The present application relates to the technical field of engines, particularly to the field of measurement of the throat area of an engine, and specifically to a method and system for calibrating a device for measuring the throat area. Background Art

[0002] As is well known, the minimum exhaust side area in the converging channel of the guide vane through which the gas flows is called the throat area of the guide vane. The size of the throat area of the turbine guide vane is an important parameter that directly affects the performance of the engine. Practice has proved that the change in the throat area of the first-stage guide vane of the high-pressure turbine has an impact on the high-pressure speed, thrust, M2 performance, T4 temperature, and fuel consumption rate of the engine. Therefore, the throat area of the engine blade is an important parameter for engine assembly and commissioning. The measurement of the throat area is the key to blade assembly. The blade passage is a spatial curved surface passage formed by the upper and lower flange plates of the blade and the blade profiles between every two blades, as Figure 1 shown in

[0003] However, because the structure of the guide vane is complex, the measurement of its throat area has become the key in the engine manufacturing and assembly process. Currently, the commonly used method for measuring the throat area is to use a coordinate measuring machine for measurement. The measurement process is as follows:

[0004] Place the turntable on the coordinate measuring machine; then place the casing unit with the guide vane assembly on the turntable; then perform centering, that is, align the axis of the turbine guide vane with the axis of the turntable; then use the coordinate measuring machine to measure the area of the first throat window; after the measurement is completed, control the turntable to move by a dividing angle, and then measure the area of the next throat window.

[0005] Figure 2 The schematic diagram of the coordinate measuring method is shown in

[0006] However, the throat is a spatial structure formed by a complex curved surface. It is actually impossible to obtain the true value of the throat area using the existing methods and devices. Therefore, it is impossible to accurately evaluate the measurement result of the throat area. For example, when the measurement difference of the throat area exceeds a predetermined threshold, those skilled in the art cannot determine whether it is a problem with the structure of the turbine guide vane itself or a problem with the hardware of the device for measuring the throat area.

[0007] Therefore, there is an urgent need in the art for a method and system for calibrating a device for measuring the throat area. Summary of the Invention

[0008] The object of the present invention is to provide a calibration method and system for a throat area detection device. This calibration method utilizes a standard sample system to ensure that when the three-coordinate method is used for measuring the throat area, the hardware such as the coordinate measuring machine, the turntable, and the clamping tool are in a normal working state, thereby eliminating the problem that the abnormal measurement result is caused by the hardware.

[0009] A brief overview of one or more aspects is given below to provide a basic understanding of these aspects. This overview is not an exhaustive survey of all contemplated aspects, and is neither intended to identify key or decisive elements of all aspects nor to define the scope of any or all aspects. Its sole purpose is to present some concepts of one or more aspects in a simplified form as a prelude to the more detailed description that follows.

[0010] According to one aspect of the present application, a calibration method for a throat area detection device is provided. The calibration method includes the following steps: fabricating a standard sample, which includes a guide vane sample and a standard mounting disc; mounting the standard mounting disc on the turntable of the detection device; measuring the throat area S1 of the guide vane sample at position P1; measuring the throat area Sn of the guide vane sample at position Pn; determining whether the error between S1 and Sn exceeds a first predetermined threshold, and if so, troubleshooting the detection device, wherein the area of the guide vane sample is the same at each radial position.

[0011] According to a preferred embodiment of the present application, the calibration method further includes: determining the average value Svt1 of the throat area of the guide vane sample measured at time t1; determining the throat area Svtm of the guide vane sample measured at a time tm different from t1; determining whether the error between Svt1 and Svtm exceeds a second predetermined threshold, and if so, troubleshooting the detection device.

[0012] According to a preferred embodiment of the present application, position P1 and position Pn are set in the throat window of the guide vane sample, and n is at least equal to 2.

[0013] According to a preferred embodiment of the present application, the first predetermined threshold and the second predetermined threshold are the same.

[0014] According to a preferred embodiment of the present application, the first predetermined threshold and the second predetermined threshold are different.

[0015] According to a preferred embodiment of the present application, the settings of time t1 and time tm depend on: the calibration period, the calibration cycle, the usage period, and the usage frequency, and m is at least equal to 2.

[0016] According to a preferred embodiment of the present application, the throat area detection device is a coordinate measuring machine.

[0017] According to a preferred embodiment of the present application, the calibration method further includes: measuring the standard sample with a coordinate measuring machine with higher precision; and further calibrating the throat area detection device based on the accuracy comparison between systems.

[0018] According to a second aspect of the present application, there is provided a calibration system for a throat area detection device for implementing the method as described above.

[0019] The system includes: a standard sample, the standard sample including a guide vane sample and a standard mounting plate. And, the standard mounting plate can be mounted on the turntable of the detection device, and the areas of the guide vane samples at various radial positions are the same.

[0020] To achieve the foregoing and related purposes, one or more of these aspects include the features that are fully described hereinafter and particularly pointed out in the appended claims. The following description and the drawings set forth in detail certain illustrative features of one or more of these aspects. However, these features are merely indicative of the several ways in which the principles of the various aspects may be employed, and this description is intended to cover all such aspects and their equivalents. Brief Description of the Drawings

[0021] For a more particular understanding of the manner in which the above-recited features of the present application are used, reference may be had to the aspects, some of which are illustrated in the drawings. It should be noted, however, that the drawings illustrate only certain typical aspects of the present application and are not to be considered limiting of its scope, for the description may admit of other equally effective aspects.

[0022] In the drawings:

[0023] Figure 1 is a schematic structural diagram of a turbine guide vane according to an embodiment of the present application;

[0024] Figure 2 is an assembly schematic diagram for measuring the throat area of a turbine guide vane using a coordinate measuring machine;

[0025] Figure 3 is a schematic diagram of the integral ring throat structure of a guide vane in the prior art;

[0026] Figure 4 is a schematic diagram of a part of a calibration system of a coordinate measuring machine according to an embodiment of the present application; and

[0027] Figure 5 is a flowchart of a calibration method for a throat area detection device according to an embodiment of the present application.

[0028] Description of the Reference Numerals

[0029] 1 upper edge plate

[0030] 2 Lower edge plate

[0031] 3 Guide vane

[0032] 4 Coordinate measuring machine

[0033] 5 Workpiece to be measured

[0034] 6 Turntable

[0035] 7 Guide vane sample

[0036] 8 Standard mounting disc Detailed implementation manners

[0037] The following detailed description in conjunction with the accompanying drawings is intended as a description of various configurations and is not intended to represent the only configurations in which the concepts described herein can be practiced. This detailed description includes specific details to provide a thorough understanding of the various concepts. However, it will be apparent to those skilled in the art that these concepts can be practiced without these specific details. In some instances, well-known components are shown in block diagram form to avoid obscuring such concepts.

[0038] It should be understood that based on this disclosure, other embodiments will be apparent and systematic, structural, process, or mechanical changes can be made without departing from the scope of this disclosure.

[0039] As Figure 1 shown, the guide vane structure is mainly divided into three parts: the upper edge plate 1, the lower edge plate 2, and the guide vane 3. The air flow channel formed between adjacent guide vanes 3 of the turbine guide vane is the throat window described herein. The throat area refers to the minimum interface area formed by a relatively independent air flow channel combined by every two adjacent blades of the exhaust guide vane and the upper and lower edge plates.

[0040] Figure 2 The schematic diagram of measuring the throat area by using the coordinate measuring method in the prior art is shown.

[0041] As Figure 2 shown, the existing coordinate measuring method for the throat area is as follows: The turbine guide vane (shown as the workpiece 5 to be measured in the figure) is installed on the turntable 6, and then the turntable 6 is placed on the coordinate measuring machine 4. Subsequently, centering is performed, that is, the axis of the turbine guide vane is aligned with the axis of the turntable. Then, the area of the first throat window is measured by using the coordinate method. After the measurement is completed, the turntable 6 is rotated by a dividing angle, and then the area of the next throat window is measured.

[0042] However, as Figure 3As shown in the figure, the cross-section of the throat is a twisted spatial surface. The space is small, and the directions of each measurement point have different spatial angles, making it very difficult to obtain accurate measurements. Therefore, errors often occur during actual measurements. As a result, it is impossible to obtain the true value of the throat area using existing methods and equipment, and thus it is impossible to calibrate and correct the measurement results of the coordinate measuring machine. Moreover, due to the errors in the measurement itself, problems and failures may also occur in the coordination of hardware such as the coordinate measuring machine, turntable, and clamping tools. Therefore, it is difficult for those skilled in the art to determine the exact source of the errors, resulting in the problem that abnormal measurement results cannot be traced back.

[0043] To address the above technical difficulties, the present application proposes a calibration method and system for a throat area detection device.

[0044] Figure 4 The figure shows a schematic diagram of a part of the calibration system described above. First, the system includes a guide vane sample 7, which is identical to a traditional turbine guide vane in terms of external dimensions and is used to simulate a traditional turbine guide vane assembly. However, the throat structure of the guide vane sample 7 is different from that of a traditional turbine guide vane. The difference is that the throat interface of a traditional guide vane is a twisted spatial surface, so the areas at measurement points in various angles are different. In contrast, the throat of the guide vane sample 7 is not a twisted surface structure, so the areas in each radial direction are exactly the same.

[0045] Moreover, the guide vane sample only needs to retain the positioning device and the throat window, and other components, such as but not limited to: air film holes, front cavity, rear cavity, and honeycomb, may not be included. Therefore, the manufacturing process of the sample is very simple and easy.

[0046] The system further includes a standard mounting plate 8, on which the guide vane sample 7 can be positioned and installed. The standard mounting plate 8 has at least two positioning devices in the axial direction. The positioning device can be implemented using various positioning structures known in the art. Such as but not limited to positioning pins, positioning bolts, clamping-type positioning devices, baffles, etc. All these positioning structures are within the scope of the present application.

[0047] The axial and circumferential positioning of the guide vane sample 7 is achieved through the above positioning structure. Moreover, this positioning structure is very easy to disassemble and assemble, so that the guide vane sample 7 and the standard mounting plate 8 can be conveniently removed from the turntable after the calibration procedure is completed.

[0048] The standard mounting plate 8 can be installed on the turntable 6 of the coordinate measuring machine, and then the throat area of the guide vane sample 7 is measured according to the coordinate measuring method.

[0049] As described above, the throat structure of the guide vane sample 7 has exactly the same area in each radial direction. Therefore, after it is installed on the standard mounting plate 8, by rotating the indexing angle of the turntable, the throat areas measured at at least two positioning positions should theoretically be exactly the same. If the measurement results are inconsistent and this deviation exceeds a certain threshold (which can be hereinafter referred to as the "first predetermined threshold"), it indicates that there is a problem with the hardware structure of the throat area detection device. Therefore, it is necessary to check its hardware to eliminate the fault. This fault may include but is not limited to hardware problems of the coordinate measuring machine itself (uncalibrated, uncalibrated), turntable installation problems, clamping tool matching problems, and so on.

[0050] As can be appreciated by those skilled in the art, the setting of the first predetermined threshold can be set by them according to actual work needs. The first predetermined threshold may depend on but is not limited to the following factors: machining accuracy, measurement error, actual process parameters, and so on.

[0051] In the above embodiments, two positioning positions are described. However, as can be understood by those skilled in the art, the number of positioning devices can be greater than 2, and its number can be fully set according to actual needs. And, as can be appreciated by those skilled in the art, with the increase in the number of positioning devices, the measurement accuracy will also be correspondingly improved.

[0052] In addition to achieving angular measurement through positioning devices positioned in different axial and circumferential directions in space, the embodiments of the present application can also calibrate the throat area measuring device within a certain time window. For example, at time point t1, the throat area of the guide vane sample 7 is detected and its average value is obtained.

[0053] Similarly, at a time point tm different from time point t1, the throat area of the guide vane sample 7 is detected again and its average value is obtained again. By comparing the average throat areas at different time points, the performance of the throat area measuring device in a certain time dimension can be calibrated. Specifically, if the difference between the two average areas does not meet the evaluation requirements of the guide vane uncertainty, that is, if it exceeds the preset second predetermined threshold, it proves that there may be a hardware problem with the throat area measuring device during this calibration / calibration / usage cycle, and it is necessary to check and troubleshoot.

[0054] Similarly, as can be appreciated by those skilled in the art, the setting of the second predetermined threshold can be set by them according to actual work needs. The second predetermined threshold may also depend on but is not limited to the following factors: machining accuracy, measurement error, actual process parameters, and so on. And, the first predetermined threshold and the second predetermined threshold can be the same or different.

[0055] Further, as can be understood by those skilled in the art, the selection of time t1 and tm can be carried out according to actual working needs. For example, various working requirements such as calibration period, calibration cycle, service life, and usage frequency are comprehensively considered. Moreover, the number of selected time points can be more than two, that is, m is at least equal to 2, and its quantity can be set completely according to actual needs. Further, as can be appreciated by those skilled in the art, as the number of devices for measuring time measurement points increases, the measurement accuracy will be correspondingly improved. All these embodiments fall within the scope of this application.

[0056] By comparing and evaluating the measurement results of the throat area detection device in two dimensions of space and time respectively, the performance of the detection device can be calibrated very accurately, so that accurate traceability can be carried out after problems occur in the measurement results.

[0057] The following combines Figure 4 the structure of Figure 5 to describe the calibration method of the throat area detection device of this application.

[0058] As Figure 5 shown, the calibration method mainly includes the following steps.

[0059] In step S1, a standard sample is made. As described above, the standard sample at least includes a guide vane sample 7 and a standard mounting disc 8.

[0060] The guide vane sample used in this application is different from the conventional guide vane. The difference lies in that the throat interface of the conventional guide vane is a twisted spatial curved surface, so the areas at the measuring points at various angles are different, which makes it difficult to obtain its fixed value. On the contrary, the throat of the guide vane sample 7 is not a twisted curved surface structure, so the areas in each radial direction are exactly the same. And its structure is simple and convenient to manufacture.

[0061] Next, in step S2, the standard mounting disc 8 is installed on the turntable 6 of the detection device as Figure 2 shown.

[0062] Thereafter, in steps S3 to S4, n measurement positions P1,..., Pn are set in one or more throat windows of the guide vane sample, where n is at least equal to 2, and as the number of n increases, the measurement accuracy will be correspondingly improved. As can be understood by those skilled in the art, positions P1 to Pn can be set on the flange of the guide vane.

[0063] Measure the values of the throat areas at n positions, that is, determine the corresponding throat areas S1,..., Sn.

[0064] The movement from position P1 to position Pn can be achieved by rotating the turntable 6 by the corresponding indexing angle.

[0065] Then, in step S5, it is determined whether the error between S1 and Sn exceeds a first predetermined threshold, and if so, it proves that there is a problem with the hardware of the detection system. Thus, in step S6, the detection device is checked to eliminate its error.

[0066] In addition to calibrating the detection system by measuring the throat area of the guide piece sample in the spatial dimension, the solution according to the present application can also be calibrated in the time dimension. This solution can be achieved through the following steps.

[0067] First, in step S7, the average value Svt1 of the throat area of the guide piece sample measured at time t1 is determined.

[0068] Secondly, in step S8, the throat area Svtm of the guide piece sample measured at a time tm different from t1 is determined.

[0069] As those skilled in the art can understand, m is at least equal to 2, and as the number of m increases, the measurement accuracy will also increase accordingly.

[0070] Thirdly, in step S9, it is determined whether the error between Svt1 and Svtm exceeds a second predetermined threshold, and if so, it proves that there is a problem with the hardware of the detection system. Thus, the detection device is checked (i.e., return to step S6) to eliminate its error.

[0071] The selection of the first predetermined threshold and the second predetermined threshold is set according to the actual working requirements, and the two can be the same or different. And the setting of time t1 and time tm may depend on factors such as but not limited to: calibration period, calibration cycle, usage period, and usage frequency of the guide piece, etc.

[0072] By analyzing and comparing the measurement results of the throat area detection device in both the spatial dimension and the time dimension, the performance of the detection device can be calibrated and calibrated very accurately. Thus, during actual use, if there is a problem with the measurement result, the error can be accurately traced.

[0073] Moreover, as the number of spatial measurement positions and the number of time measurement points increase, the accuracy of the calibration system and method will be further improved, so that the hardware problems of the detection system can be accurately located, and thus the accuracy of the existing detection system can be accurately evaluated.

[0074] Meanwhile, the hardware structure of the detection system and method is relatively not complex, and there is no need to modify the hardware of the existing detection system. Moreover, the calibration method has a fast implementation speed and high accuracy, and has very good practicability.

[0075] According to various aspects, elements, or any part of an element, or any combination of elements of the present disclosure, it can be implemented by a "processing system" including one or more processors. Examples of processors include: microprocessors, microcontrollers, digital signal processors (DSPs), field programmable gate arrays (FPGAs), programmable logic devices (PLDs), state machines, gated logic, discrete hardware circuits, and other suitable hardware configured to perform the various functions described throughout the present disclosure. One or more processors in the processing system can execute software. Software should be broadly interpreted to mean instructions, instruction sets, code, code segments, program code, programs, subroutines, software modules, applications, software applications, software packages, routines, subroutines, objects, executables, execution threads, procedures, functions, etc., regardless of whether it is referred to in terms of software, firmware, middleware, microcode, hardware description language, or other terms. The software can reside on a computer-readable medium. The computer-readable medium can be a non-transitory computer-readable medium. As an example, non-transitory computer-readable media include: magnetic storage devices (e.g., hard disks, floppy disks, magnetic strips), optical disks (e.g., compact disks (CDs), digital versatile disks (DVDs)), smart cards, flash memory devices (e.g., memory cards, memory sticks, key drives), random access memory (RAM), read-only memory (ROM), programmable ROM (PROM), erasable PROM (EPROM), electrically erasable PROM (EEPROM), registers, removable disks, and any other suitable medium for storing software and / or instructions that can be accessed and read by a computer. As an example, the computer-readable medium can also include carrier waves, transmission lines, and any other suitable medium for transmitting software and / or instructions that can be accessed and read by a computer. The computer-readable medium can reside within the processing system, outside the processing system, or be distributed across multiple entities including the processing system. The computer-readable medium can be implemented in a computer program product. As an example, the computer program product can include a computer-readable medium in a packaging material. Those skilled in the art will recognize how to best implement the described functionality presented throughout the present disclosure depending on the specific application and overall design constraints imposed on the overall system.

[0076] It should be understood that the specific order or hierarchy of the steps in the disclosed methods is an illustration of exemplary processes. Based on design preferences, it should be understood that the specific order or hierarchy of the steps in the methods or method systems described herein can be rearranged. The appended method claims present the elements of the various steps in a sample order and are not meant to be limited to the specific order or hierarchy presented, unless specifically recited herein.

[0077] The foregoing description is provided to enable any person skilled in the art to practice the various aspects described herein. Various modifications to these aspects will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other aspects. Thus, the claims are not intended to be limited to the aspects shown herein, but are to be accorded the full scope consistent with the language of the claims, wherein the recitation of a singular element is not intended to mean "one and only one" (unless specifically so stated) but "one or more." Unless specifically stated otherwise, the term "some" refers to one or more. A phrase that recites "at least one" of a list of items refers to any combination of those items, including a single member. As an example, "at least one of a, b, or c" is intended to cover: at least one a; at least one b; at least one c; at least one a and at least one b; at least one a and at least one c; at least one b and at least one c; and at least one a, at least one b, and at least one c. Elements of the various aspects described throughout this disclosure that are presently known or later come to be known to those of ordinary skill in the art as all structural and functional equivalents thereof are expressly incorporated herein by reference and are intended to be covered by the claims. Furthermore, nothing disclosed herein is intended to be dedicated to the public, whether or not such disclosure is explicitly recited in the claims.

Claims

1. A calibration method for a throat area detection device, the calibration method comprising the following steps: Making a standard sample, wherein the standard sample includes a guide sample and a standard mounting plate; Installing the standard mounting plate onto the turntable of the detection device; Measuring the throat area S1 of the guide sample at position P1; Measuring the throat area Sn of the guide sample at position Pn; Determine whether the error between S1 and Sn exceeds a first predetermined threshold, and if so, check the detection device, The area of ​​the guide sample is the same at each radial position.

2. The calibration method according to claim 1, characterized in that: The calibration method further comprises: Determine an average value Svt1 of the throat area of ​​the guide sample measured at time t1; Determine the throat area Svtm of the guide sample measured at a time tm different from t1; Determine whether the error between Svt1 and Svtm exceeds a second predetermined threshold, and if so, check the detection device.

3. The calibration method according to claim 1 or 2, characterized in that the position P1 and the position Pn are set in the throat window of the guide sample, and n is at least equal to 2.

4. The calibration method according to claim 1 or 2, characterized in that the first predetermined threshold value and the second predetermined threshold value are the same.

5. The calibration method according to claim 1 or 2, characterized in that the first predetermined threshold value and the second predetermined threshold value are different.

6. The calibration method as described in claim 1 or 2 is characterized in that the setting of time t1 and time tm depends on: a verification period, a calibration period, a usage period, and a usage frequency, and m is at least equal to 2.

7. The calibration method according to claim 1 or 2, characterized in that the throat area detection device is a three-coordinate measuring machine.

8. The calibration method according to claim 7, characterized in that: The calibration method further comprises: Measuring the standard sample with a higher precision three-dimensional coordinate measuring machine; and The throat area detection device is further calibrated based on the accuracy comparison between systems.

9. A calibration system for a throat area detection device, used to implement the method according to any one of claims 1 to 8, the system comprising: A standard sample, wherein the standard sample comprises a guide sample and a standard mounting plate, wherein the standard mounting plate is mounted to the turntable of the detection device, and The area of ​​the guide sample is the same at each radial position.

10. The calibration system according to claim 9, characterized in that: The throat area detection device is a three-coordinate measuring instrument.

11. The calibration system according to claim 10, characterized in that: Measuring the standard sample using a higher-precision three-dimensional coordinate measuring machine; and The throat area detection device is further calibrated based on the accuracy comparison between systems.

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