Wedge design method for phased array ultrasonic testing of flue gas turbine model-stage moving blades

Abstract

The present invention discloses a wedge design method for phased array ultrasonic detection of model-level moving blades of a flue gas turbine, comprising: generating a three-dimensional model diagram of a model-level moving blade of a flue gas turbine; distinguishing the working surface and the back surface of the three-dimensional model diagram; stress zoning the three-dimensional model diagram according to the stress levels of different parts of the model-level moving blades of the flue gas turbine; selecting an area on the three-dimensional model diagram where the stress value is greater than a preset threshold, and statistically analyzing the three-dimensional flow surface data of the area; analyzing the flow surface curvature of the working surface and the back surface of the three-dimensional model diagram with the minimum outer dimensions of the proposed phased array detector probe as the analysis area; selecting a number of curvatures covering a preset ratio or more of the flow surface data points from the obtained flow surface curvatures; determining the manufacturing parameters of the wedge based on the selected curvatures; and manufacturing the wedge. The design method of the present invention can form wedges for phased array ultrasonic detection of moving blades of different model levels.

Description

Technical Field

[0001] The invention relates to the technical field of detection of moving blades of a flue gas turbine, and in particular to a wedge design method for phased array ultrasonic detection of moving blades of a model-level flue gas turbine. Background Art

[0002] The scale of domestic catalytic devices varies from 4000kW to 40000kW due to different construction periods, processes and equipment manufacturing capabilities. Flue gas has thermal energy and pressure energy. According to the flue gas pressure and temperature parameters of different catalytic processes and the flue gas thermal performance design criteria, multiple basic model-level blades have been formed. Most of these basic model-level blades are reactionary three-dimensional flow blades with high efficiency. Through similar principles, the design of flue gas turbine blades of different device scales can be carried out to meet the flue gas capacity recovery requirements of different processes and device scales.

[0003] The aerodynamic structure of the flue gas turbine's moving blades is a three-dimensional curved structure, and the blade root is a tree-branch-shaped structure. The overall structural shape of the moving blades is complex, and conventional non-destructive testing methods cannot effectively detect them, nor can they detect the tiny original manufacturing defects inside and under the shallow surface, and the fatigue expansion defects after one or more cycles of operation. As a result, the moving blades of the flue gas turbine suddenly break during normal operation, causing fluctuations in the device and failing to achieve "long, full, and optimal" operation, bringing huge losses and hidden dangers to production safety and environmental protection for oil refining and petrochemical companies.

[0004] At present, the only domestic manufacturing standard HG / T 3650-2012 "Technical Conditions for Flue Gas Turbines" only has conventional A-type ultrasonic testing requirements for rolled bars for flue gas turbine moving blades, and no ultrasonic testing requirements for subsequent die forging and performance heat treatment. There is only a PT testing requirement for the surface of the moving blades after fine machining. The flue gas turbine enters the overhaul stage after one cycle of use. At present, domestic refineries and petrochemical companies have formulated their own overhaul specifications with reference to the manufacturing standards, and only visual and PT inspections are performed on the surface of the flue gas turbine. The above non-destructive testing methods cannot detect the superficial surface and internal tiny original manufacturing defects of the flue gas turbine moving blades and fatigue expansion defects after one or more cycles of operation. With the improvement of national industrial policies and environmental protection requirements, the stable operation cycle of various petrochemical units has transitioned from the previous 3 years to 4 years, and to the recent 5 years, which has put forward higher requirements for the inherent safety and quality of the equipment.

[0005] At present, the country's environmental protection requirements for oil refining and petrochemical equipment will be further improved. If the non-destructive testing methods and requirements for the manufacturing process and overhaul process of flue gas turbine moving blades in the original standard are still used, it will no longer be able to meet the owner's requirements. In order to realize the phased array ultrasonic testing of the reaction blade type moving blades of the flue gas turbine, in addition to the testing methods, it is necessary to solve the phased array ultrasonic testing of the blade body of the reaction blade type moving blade of the model-level flue gas turbine. Therefore, the wedge block that cooperates with the probe is also one of the core links. The fit between the wedge block and the test part determines the scanning quality of the phased array probe on the blade body. In order to realize the full scanning of the stress concentration area of ​​the blade body of the three-dimensional flow aerodynamic structure moving blade by the phased array ultrasonic probe, the bonding of the probe and the blade body becomes one of the key links. The wedge blocks used for conventional phased array testing are basically planar structures or inclined plane structures, and cannot achieve the fit of the three-dimensional flow curved surface. Summary of the invention

[0006] In view of the above technical problems, the present invention provides a wedge design method for phased array ultrasonic detection of model-level moving blades of a flue gas turbine, so as to form wedges for phased array ultrasonic detection of moving blades of different model levels, which can be matched with specific instruments and probes to complete the scanning of the blade bodies of moving blades of different model levels.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] A wedge design method for phased array ultrasonic testing of a flue gas turbine model-level moving blade comprises the following steps:

[0009] Generate a three-dimensional model diagram of the moving blades of the flue gas turbine model stage;

[0010] Distinguishing between a working surface and a back surface of the three-dimensional model diagram;

[0011] Stress partitioning of the three-dimensional model diagram is performed according to the stress levels of different parts of the moving blades of the flue gas turbine model stage;

[0012] Selecting an area on the three-dimensional model graph where the stress value is greater than a preset threshold, and counting the three-dimensional flow surface data of the area;

[0013] Analyzing the curvature of the flow surface of the working face and the back face of the three-dimensional model diagram by taking the minimum outer dimensions of the proposed phased array detector probe as the analysis area;

[0014] Selecting a number of curvatures covering a predetermined ratio or more of the stream surface data points from the obtained stream surface curvatures;

[0015] Determining manufacturing parameters of the wedge based on the selected curvatures;

[0016] The wedges are made.

[0017] In one embodiment of the present invention, the stress zones include but are not limited to the stress zone at the blade root, the stress zone at the junction of the blade root and the blade body, and the stress zone at the middle of the blade body.

[0018] In one embodiment of the present invention, based on the thermal stress, centrifugal force and front-rear differential pressure stress of the flue gas turbine and its model-level moving blades, stress analysis is performed by finite element analysis to determine the area where the stress value is greater than a preset threshold.

[0019] In one embodiment of the present invention, the method of analyzing the curvature of the flow surface of the working surface and the back surface of the three-dimensional model diagram based on the minimum outer dimensions of the proposed phased array detector probe as the analysis area comprises:

[0020] Taking the minimum outer dimension of the proposed phased array detector probe as the analysis area, the flow surface data change trend of the working surface and the back side of the three-dimensional model diagram is analyzed; taking the height direction of the three-dimensional model diagram as the reference point of the stress distribution concentration area of ​​the working surface and the back side of the three-dimensional model diagram, taking the minimum outer dimension of the phased array detector probe as the equal width line to intercept the dimension of the three-dimensional model diagram along the width direction, taking the reference point as the horizontal axis, and dividing it into the flow surface point data value frame according to the outer dimension of the phased array detector probe, the flow surface curvature of the working surface and the back side of the three-dimensional model diagram is obtained by the stepwise approximation and iteration method.

[0021] In one embodiment of the present invention, the step of selecting a plurality of curvatures covering a predetermined ratio or more of the flow surface data points from the obtained flow surface curvatures comprises:

[0022] Based on the curvatures of the flow surfaces on the working face and the back face of the three-dimensional model diagram and their changing trends, at least one of the curvatures covering the flow surface data points above a preset ratio is selected.

[0023] In one embodiment of the present invention, the step of determining the manufacturing parameters of the wedge based on the selected curvatures includes:

[0024] Determine the arc surface size of the fitting surface between the wedge block and the phased array detector probe based on the selected curvatures;

[0025] The wedge block is manufactured to be assembled with the phased array detector probe with a minimum contact plane.

[0026] In one embodiment of the present invention, before the step of making the wedge block, the method further comprises:

[0027] simulating the wedge according to the manufacturing parameters of the wedge;

[0028] Adapting the simulated wedge to the arc surface size of the phased array detector probe fitting surface;

[0029] Complete the simulation fitting test of the wedge block on the three-dimensional model diagram.

[0030] In one embodiment of the present invention, before the step of generating a three-dimensional model diagram of the flue gas turbine model-level moving blades, the step further includes: obtaining authorization for the use of the flue gas turbine model-level moving blades.

[0031] In one embodiment of the present invention, the method of generating a three-dimensional model diagram of a model-level moving blade of a flue gas turbine includes but is not limited to: legally obtaining the three-dimensional model diagram from the owner of the model-level moving blade; or generating the three-dimensional model diagram through a two-dimensional diagram authorized by the owner of the model-level moving blade; or using reverse engineering to map the authorized model-level moving blade to generate a three-dimensional model diagram.

[0032] The present invention establishes three-dimensional models of moving blades of different model levels separately, and selects several groups of curvatures with a wide spectrum as the dimensions of the fitting surfaces between the wedge and the moving blade according to the aerodynamic profile data or curvature of the working surface and the back surface, so as to form wedges for phased array ultrasonic detection of moving blades of different model levels, which can be matched with specific instruments and probes to complete the scanning of the blade bodies of moving blades of different model levels. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The accompanying drawings herein are incorporated into and constitute a part of the specification, illustrate embodiments consistent with the present invention, and together with the specification are used to explain the principles of the present invention. Obviously, the accompanying drawings described below are only some embodiments of the present invention, and for those of ordinary skill in the art, other accompanying drawings can be obtained based on these accompanying drawings without creative work.

[0034] Figure 1 It is a flow chart of a method for designing wedges for phased array ultrasonic testing of model-stage moving blades of a flue gas turbine in one embodiment of the present invention. DETAILED DESCRIPTION

[0035] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in a variety of forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that the present invention will be comprehensive and complete and fully convey the concepts of the example embodiments to those skilled in the art. The same reference numerals in the figures represent the same or similar structures, and thus their repeated description will be omitted.

[0036] It should be noted that in some of the processes described in the specification and claims of the present invention and the above-mentioned drawings, multiple operations appearing in a specific order are included, but it should be clearly understood that these operations may not be executed in the order in which they appear in this document or may be executed in parallel, and the serial numbers of the operations, such as step S100, step S200, etc., are only used to distinguish different operations, and the serial numbers themselves do not represent any execution order. In addition, these processes may include more or fewer operations, and these operations may be executed in sequence or in parallel, and therefore cannot be understood as limiting the present invention.

[0037] In order to make the purpose, technical solution and advantages of the present invention clearer, the wedge design method for phased array ultrasonic testing of model-level moving blades of a flue gas turbine for which protection is sought in the present invention will be further elaborated in detail below in conjunction with specific embodiments.

[0038] Figure 1 FIG. 1 is a flow chart of a method for designing a wedge for phased array ultrasonic testing of a model-level moving blade of a flue gas turbine according to an embodiment of the present invention. Figure 1 As shown, this embodiment discloses a wedge design method for phased array ultrasonic testing of a model-level moving blade of a flue gas turbine, which comprises the following steps:

[0039] S100, generating a three-dimensional model diagram of a flue gas turbine model stage moving blade;

[0040] In one embodiment of the present invention, before generating the three-dimensional model diagram of the flue gas turbine model-level moving blades, that is, step S100, it also includes: obtaining authorization for use of the flue gas turbine model-level moving blades.

[0041] In one embodiment of the present invention, the method of generating a three-dimensional model diagram of a model-level moving blade of a flue gas turbine includes but is not limited to: legally obtaining the three-dimensional model diagram from the owner of the model-level moving blade; or generating the three-dimensional model diagram through a two-dimensional diagram authorized by the owner of the model-level moving blade; or using reverse engineering to map the authorized model-level moving blade to generate a three-dimensional model diagram.

[0042] S200, distinguishing a working surface and a back surface of the three-dimensional model image;

[0043] S300, stress partitioning the three-dimensional model diagram according to stress levels of different parts of the moving blades of the flue gas turbine model stage;

[0044] In one embodiment of the present invention, according to the distribution of the root part, the joint surface between the blade root and the blade body, and the middle part of the blade body of the flue gas turbine model stage moving blade on the three-dimensional model diagram, the stress zone of the three-dimensional model diagram can be divided into a blade root stress zone, a blade root and blade body joint surface stress zone, and a blade body middle stress zone according to the force level.

[0045] S400, selecting an area on the three-dimensional model graph where the stress value is greater than a preset threshold, and counting the three-dimensional flow surface data of the area;

[0046] In one embodiment of the present invention, based on the thermal stress, centrifugal force and the differential pressure stress of the front and rear blades of the flue gas turbine and the model stage, stress analysis is performed by finite element analysis to determine the area where the stress value is greater than a preset threshold. For example, when it is necessary to select an area with a large stress value for calculation, it is necessary to set a threshold for the stress value. When the stress value of a certain area is greater than the threshold, it is the area with a large stress value that we want to calculate.

[0047] S500, analyzing the curvature of the flow surface of the working face and the back face of the three-dimensional model diagram by taking the minimum outer dimensions of the proposed phased array detector probe as the analysis area;

[0048] Furthermore, the minimum outer dimensions of the proposed phased array detector probe can be used as the analysis area to analyze the flow surface data change trends of the working surface and the back surface of the three-dimensional model diagram; the height direction of the three-dimensional model diagram is used as the reference point of the stress distribution concentration area of ​​the working surface and the back surface of the three-dimensional model diagram, and the minimum outer dimensions of the phased array detector probe are used as the equal width line to intercept the dimensions of the three-dimensional model diagram along the width direction. The reference point is used as the horizontal axis and the outer dimensions of the phased array detector probe are evenly divided into flow surface point data value frames, and the flow surface curvature of the working surface and the back surface of the three-dimensional model diagram is obtained by the stepwise approximation and iteration method.

[0049] S600, selecting a plurality of curvatures covering a predetermined ratio or more of the stream surface data points from the obtained stream surface curvatures;

[0050] In one embodiment of the present invention, the step of selecting a plurality of curvatures covering a preset ratio of the stream surface data points from the obtained stream surface curvatures includes: selecting at least one of the plurality of curvatures covering a preset ratio of the stream surface data points based on the stream surface curvatures of the working surface and the back surface of the three-dimensional model diagram and their changing trends. For example, the curvatures covering 60% or more of the stream surface data points can be selected by screening to determine the manufacturing parameters of the wedge.

[0051] S700, determining the manufacturing parameters of the wedge block based on the selected curvatures; in one embodiment of the present invention, the manufacturing parameters of the wedge block based on the selected curvatures include: determining the arc surface size of the wedge block and the phased array detector probe based on the selected curvatures; the manufactured wedge block should be assembled with the phased array detector probe with the minimum contact plane. And

[0052] S800, manufacturing the wedge.

[0053] In one embodiment of the present invention, before the step of making the wedge block, the method further comprises:

[0054] simulating the wedge according to the manufacturing parameters of the wedge;

[0055] Adapting the simulated wedge to the arc surface size of the phased array detector probe fitting surface;

[0056] Complete the simulation fitting test of the wedge block on the three-dimensional model diagram.

[0057] The present invention establishes three-dimensional models of moving blades of different model levels separately, and selects several groups of curvatures with a wide spectrum as the dimensions of the fitting surfaces between the wedge and the moving blade according to the aerodynamic profile data or curvature of the working surface and the back surface, so as to form wedges for phased array ultrasonic detection of moving blades of different model levels, which can be matched with specific instruments and probes to complete the scanning of the blade bodies of moving blades of different model levels.

[0058] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention is described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A wedge design method for phased array ultrasonic testing of flue gas turbine model-level moving blades, characterized in that: include: Generate a three-dimensional model diagram of the moving blades of the flue gas turbine model stage; Distinguishing between a working surface and a back surface of the three-dimensional model diagram; Stress partitioning of the three-dimensional model diagram is performed according to the stress levels of different parts of the moving blades of the flue gas turbine model stage; Selecting an area on the three-dimensional model graph where the stress value is greater than a preset threshold, and counting the three-dimensional flow surface data of the area; Analyzing the curvature of the flow surface of the working face and the back face of the three-dimensional model diagram by taking the minimum outer dimensions of the proposed phased array detector probe as the analysis area; Selecting a number of curvatures covering a predetermined ratio or more of the stream surface data points from the obtained stream surface curvatures; Determining manufacturing parameters of the wedge based on the selected curvatures; making the wedge; The method of analyzing the curvature of the working surface and the back surface of the three-dimensional model diagram based on the minimum outer dimensions of the proposed phased array detector probe as the analysis area comprises: Taking the minimum outer dimensions of the proposed phased array detector probe as the analysis area, analyzing the flow surface data change trends of the working face and the back face of the three-dimensional model diagram; The height direction of the three-dimensional model diagram is used as the reference point of the stress distribution concentration area on the working surface and the back surface of the three-dimensional model diagram, and the minimum outer dimension of the phased array detector probe is used as the equal width line to intercept the dimension of the three-dimensional model diagram along the width direction. The reference point is used as the horizontal axis and the outer dimension of the phased array detector probe is evenly divided into stream surface point data value frames, and the stream surface curvature of the working surface and the back surface of the three-dimensional model diagram is obtained by the stepwise approximation and iteration method.

2. The wedge design method according to claim 1, characterized in that: The stress zones include but are not limited to the stress zone at the blade root, the stress zone at the junction of the blade root and the blade body, and the stress zone in the middle of the blade body.

3. The wedge design method according to claim 1, characterized in that: Based on the thermal stress, centrifugal force and differential pressure stress of the front and rear blades of the flue gas turbine and the model stage, stress analysis is performed by finite element analysis to determine the area where the stress value is greater than a preset threshold.

4. The wedge design method according to claim 1, characterized in that: The step of selecting a plurality of curvatures covering a predetermined ratio or more of the flow surface data points from the obtained flow surface curvatures comprises: Based on the curvatures of the flow surfaces on the working face and the back face of the three-dimensional model diagram and their changing trends, at least one of the curvatures covering the flow surface data points above a preset ratio is selected.

5. The wedge design method according to claim 1, characterized in that: The step of determining the manufacturing parameters of the wedge based on the selected curvatures comprises: Determine the arc surface size of the fitting surface between the wedge block and the phased array detector probe based on the selected curvatures; The wedge block is manufactured to be assembled with the phased array detector probe with a minimum contact plane.

6. The wedge design method according to claim 1, characterized in that: Before the step of making the wedge block, the method further comprises: simulating the wedge according to the manufacturing parameters of the wedge; Adapting the simulated wedge to the arc surface size of the phased array detector probe fitting surface; Complete the simulation fitting test of the wedge block on the three-dimensional model diagram.

7. The wedge design method according to claim 1, characterized in that: Before the step of generating a three-dimensional model diagram of the flue gas turbine model-level moving blades, the method further includes: Obtain authorization for use of the flue gas turbine model-level moving blades.

8. The wedge design method according to claim 7, characterized in that: The method of generating a three-dimensional model diagram of a flue gas turbine model-level moving blade includes but is not limited to: Legally obtain the three-dimensional model drawing from the owner of the model-level rotor blade; or generating a three-dimensional model diagram through a two-dimensional diagram authorized by an owner of the model-level moving blade; Or reverse engineering is used to map the authorized model-level moving blade to generate a three-dimensional model diagram.

Images