Pipeline thermal state stress test bed, system and method and test correction method

Abstract

The pipeline thermal state stress test bench comprises a bottom plate, a pair of bearing tables and a pair of flange bases, and the pair of bearing tables are arranged on the bottom plate and used for bearing the two ends of a to-be-tested pipeline respectively; the pair of flange bases is arranged at the top of the bearing table and used for fixing the two ends of a to-be-detected pipeline respectively, one of the flange bases is fixedly connected with the bearing table, and the other flange base is arranged to be capable of moving in the axis direction of the to-be-detected pipeline relative to the bearing table; the bearing table is further provided with a baffle used for limiting the maximum moving distance of the flange base. The invention also provides a pipeline thermal state stress test system, a correction method and an experiment method. According to the test bed and the method, accurate pipeline thermal state stress distribution can be obtained.

Description

Technical Field

[0001] The invention relates to the field of testing, and in particular to the field of engine management thermal strength testing. Background Art

[0002] The external pipeline of an aircraft engine is an important part of the engine. It ensures the reliable transportation of fuel, lubricating oil, air and other media under certain environmental conditions, and provides a guarantee for the safe operation of the engine. The external pipelines are distributed throughout the low-temperature and high-temperature areas of the engine. The air pipelines are mainly concentrated in the high-temperature section and are set on the casing. It is extremely important to study the stress, deformation, stability, vibration, fatigue, high-temperature creep and other properties of the air pipelines in the high-temperature area under thermal environment and thermal load.

[0003] At present, the research on thermal strength is mainly carried out through thermal strength simulation analysis and thermal strength test. Thermal strength test has extremely high requirements for test equipment, and it is necessary to simulate the flight thermal environment and load on the ground to assess the structural strength. The existing thermal strength test bench for air duct of aircraft engine has the following problems: First, the working condition simulation is inaccurate. The air duct test piece and the engine casing tooling will undergo thermal deformation in the thermal environment. Due to the different structures and temperatures of the two, their deformation amounts are also different. In general, the thermal strength test of the pipeline fixes the two together. Due to the different structures and materials of the test tooling and the casing, the deformation amount of the test tooling is not equal to the deformation amount of the casing. Therefore, it is impossible to accurately simulate the real state of the air duct under the thermal environment and thermal load; second, the versatility is poor. The test tooling is a special tooling suitable for specific pipeline structures. The types of air ducts of aircraft engines are diverse. Each type of air duct corresponds to a test bench tooling. The test tooling cannot be universal, resulting in a waste of resources. Summary of the invention

[0004] An object of the present invention is to provide a pipeline thermal stress test bench.

[0005] Another object of the present invention is to provide a thermal stress testing system.

[0006] Another object of the present invention is to provide a thermal stress test correction method.

[0007] Another object of the present invention is to provide a pipeline thermal stress test method.

[0008] The pipeline thermal stress test bench for achieving the above-mentioned purpose is used for thermal stress test of the pipeline to be tested, and includes a base plate, a pair of bearing platforms and a pair of flange bases. The pair of bearing platforms are arranged on the base plate, respectively used to support the two ends of the pipeline to be tested; a pair of flange bases are arranged on the top of the bearing platform, respectively used to fix the two ends of the pipeline to be tested, one of the flange bases is fixedly connected to the bearing platform, and the other is arranged to be movable along the axial direction of the pipeline to be tested relative to the bearing platform; wherein the bearing platform is also provided with a baffle for limiting the maximum moving distance of the flange base.

[0009] In one or more embodiments, the flange base is movably connected to the support platform via a linear bearing.

[0010] In one or more embodiments, the supporting platform includes a water-cooled base plate and a supporting tooling, wherein a water circulation channel is provided in the water-cooled base plate and is fixedly connected to the bottom of the base plate, and the supporting tooling includes block-shaped parts and / or plate-shaped parts and / or column-shaped parts that are detachably connected to each other.

[0011] In one or more embodiments, the support platform further includes a displacement loading bolt penetrating the baffle, and the displacement loading bolt is used for fixed connection with the flange base.

[0012] In one or more embodiments, the flange base is detachably fixedly connected to the supporting platform.

[0013] To achieve the above-mentioned purpose, a pipeline thermal stress test system comprises a high temperature box and the above-mentioned thermal stress test bench, wherein the flange base of the thermal stress test bench and the pipeline to be tested are arranged in the high temperature box.

[0014] In one or more embodiments, the system further includes a temperature controller, a temperature recorder, and a temperature sensor.

[0015] In one or more embodiments, the system further includes a pressure sensor and a high temperature strain gauge attached to the pipeline to be tested.

[0016] A pipeline thermal stress test correction method for achieving the above-mentioned purpose is carried out using the above-mentioned thermal stress test system, and the method comprises the following steps: determining a theoretical casing deformation spacing; placing a thermal stress test bench in a high temperature box, heating the thermal stress test bench and the pipeline to be tested; measuring the deformation of the bearing platform after heating; and setting the difference between the casing deformation spacing and the flange base deformation as a correction spacing between the flange base and the baffle.

[0017] In order to achieve the above-mentioned purpose, the pipeline thermal stress test method first performs the above-mentioned pipeline thermal stress test correction method to correct the distance between the flange base and the baffle; then the thermal stress test bench is set in a high temperature box, the thermal stress test bench and the pipeline to be tested are heated, and the stress of the pipeline to be tested is measured.

[0018] The above-mentioned pipeline thermal stress test bench for aircraft engine air pipelines is used for normal temperature and abnormal temperature strength tests. It can simulate the thermal environment and load of the air pipeline under real flight conditions, and provide a new solution for the thermal strength test of the air pipeline. The above-mentioned thermal stress test correction method can accurately eliminate the influence of the test bench itself on the thermal deformation of the pipeline, thereby obtaining a more realistic pipeline stress distribution. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The above and other features, properties and advantages of the present invention will become more apparent through the following description in conjunction with the accompanying drawings and embodiments, in which:

[0020] Figure 1 is a schematic diagram of an embodiment of a thermal stress test bench;

[0021] Figure 2 is a top view of an embodiment of a thermal stress test bench;

[0022] Figure 3 It is a schematic diagram of the mobile terminal;

[0023] Figure 4 This is the top view of the mobile terminal;

[0024] Figure 5 It is the positioning position before heating;

[0025] Figure 6 It is a schematic diagram of the deformation measurement state after heating;

[0026] Figure 7 It is a schematic diagram of the thermal stress test system. DETAILED DESCRIPTION

[0027] The present invention is further described below in conjunction with specific embodiments and drawings. More details are elaborated in the following description to facilitate a full understanding of the present invention. However, the present invention can obviously be implemented in a variety of other ways different from the description herein. Those skilled in the art can make similar generalizations and deductions based on actual application situations without violating the connotation of the present invention. Therefore, the protection scope of the present invention should not be limited by the content of this specific embodiment.

[0028] It should be noted that these and other subsequent drawings are only examples and are not drawn to scale, and should not be used to limit the actual scope of protection required by the present invention.

[0029] Aircraft engine air ducts are generally installed on the engine casing. When heated, both will produce thermal deformation, but the deformation amount is different. Generally speaking, assuming that the casing does not deform, the deformation of the duct will be limited, resulting in greater thermal stress in the duct. Under real conditions, the casing will deform and produce a deformation amount N, which means that the duct is also allowed to produce corresponding deformation, and the deformation amount is also N. In this way, the thermal stress of the duct will be slightly reduced.

[0030] Existing air pipe thermal strength test benches often fail to consider the impact of the engine casing on the thermal deformation of the pipe. In addition, the test bench itself often has thermal deformation, resulting in the superposition of deformation, which makes the measured pipe deformation inaccurate.

[0031] Therefore, the thermal stress test bench described in the present application is used for thermal stress test of the pipeline of the engine to be tested, and comprises a bottom plate 8 , a bearing platform 12 , and a flange base 3 .

[0032] like Figure 1 As shown, a pair of supporting platforms 12, 12' are arranged on the bottom plate 8, and are used to support the two ends of the pipeline 9 to be tested respectively. Figure 1 In the illustrated embodiment, the support platform 12 includes a water-cooled base plate 7 and a support fixture 4. The support fixture 4 is used to support the test pipeline and can itself undergo thermal deformation. The water-cooled base plate 7 is fixedly connected to the base plate 8 and is arranged at the bottom of the support fixture 4. A water circulation channel is provided in the water-cooled base plate to achieve cooling of the bottom of the support fixture 4.

[0033] The support tool 4 includes block-shaped parts and / or plate-shaped parts and / or column-shaped parts that are detachably connected to each other, and is composed of a series of plate, block, and column-shaped parts. According to the structure and fixing type of the test pipeline, free combination and construction are performed to realize the universalization of the support tool 4. The flange base is also configured to be detachably connected to the support tool 4 to adapt to different types of pipelines.

[0034] The flange base 3 is arranged on the top of the bearing fixture 4, one of the flange bases 3 is fixedly connected to the bearing platform 12, and the other one is arranged to be movable along the axial direction of the pipeline 9 to be tested relative to the bearing platform 12. As shown in the figure, specifically, one of the pair of flange bases, such as Figure 1 The left flange base 3 shown is movably supported by the tooling 4 through the linear bearing 1 to form a moving end A. The flange base 3 of the moving end A moves along the axis of the pipeline. It should be noted that the axis direction of the pipeline 9 to be tested refers to the three dimensions of XYZ, not the actual axis of the pipeline 9 to be tested. Figure 1 The pipeline 9 to be tested is often a curved structure, and its axial direction is defined as the dimension of the line connecting the starting point to the end point, such as the same as the dimension Y of the length direction of the bottom plate 8.

[0035] Continue to refer to Figure 3 to Figure 4 It is understood that the linear bearing 1 includes a bearing body 101, a slide rail 102 and a limit seat 103 located at both ends of the slide rail 102, and the flange base 3 of the moving end A is fixedly connected to the bearing body 101 through a connecting piece 104. Figure 4 In the illustrated embodiment, both sides of the flange base 3 in the X direction are connected to the water-cooled base plate 7 through linear bearings 1. The linear bearings 1 can limit the lateral and vertical movement of the flange base 3, so that the flange base 3 moves only in the axial direction, thereby compensating for the axial deformation caused by thermal expansion of the test pipeline and the test fixture.

[0036] The other side of the flange base, that is, Figure 1 The right flange base 3 ′ is fixedly arranged on the bearing platform 12 ′ through a connecting piece to form a fixed end B. The flange base 3 and the pipeline 9 to be tested at the fixed end B cannot move.

[0037] It is understandable that the flange base 3 can be considered to be equivalent to the casing to which the actual aircraft engine pipeline is fixedly connected. Therefore, under the condition of heat, the flange base 3 will produce axial deformation when heated, and its deformation amount is N, which also determines the pipeline deformation amount N.

[0038] Therefore, the support platform 12 further includes a baffle 24 on which the displacement loading bolts 2 are installed. The displacement loading bolts 2 are fixedly connected to the flange base 3 and extend along the axial direction of the pipeline 9 to be tested. The baffle 24 is used to limit the maximum movement distance of the flange base 3. Figure 4 As shown, when thermal deformation occurs and the pipeline deformation reaches the deformation amount of the casing, the movable end A is constrained by the baffle 24 of the supporting fixture 4, and the deformation is limited by the fixing effect of the displacement loading bolt 2 to accurately simulate the thermal expansion displacement of the pipeline.

[0039] The maximum deformation of the flange base 3 can be considered as the distance L from the right side of the flange base 3 to the baffle 24. In theory, the distance L should be set equal to the deformation N of the pipeline, so that after heating, the pipeline deformation and stress distribution in a real heating environment can be simulated.

[0040] Combined with the introduction of the above pipeline stress test bench, we can also understand a thermal stress test system. Figure 7 As shown, it includes a high temperature box 110 and a temperature controller 112, a temperature recorder 113, a data acquisition instrument 114, a high temperature strain gauge 115, a temperature sensor 116 such as a thermocouple sensor, a gas distribution platform system 117, a pressure sensor 118 and a plurality of test holes 119, etc. The load-bearing fixture 4 and the flange base 4 of the above-mentioned thermal stress test bench are arranged in the high temperature box 110. The high temperature of the thermal stress test is loaded by the high temperature box and the temperature controller. The high temperature strain gauge 115 is attached to the pipeline 9 to be tested to obtain the stress data of the pipeline.

[0041] However, the pipeline thermal stress test bench itself will also deform due to heat, especially the bearing fixture 4 directly connected to the flange base 3. Under the premise that one end of the pipeline to be tested has been fixed by the fixed end B, the superposition of the additional deformation from the test bench directly affects the stress of the pipeline, so the management thermal stress measured by the test bench is not accurate, and the deformation of the bearing fixture 4 needs to be corrected.

[0042] The pipeline hot stress test correction method includes the following steps: determining a theoretical casing deformation spacing, i.e., L, in which the theoretical casing deformation spacing L is equal to the casing deformation N; placing the hot stress test bench in a high temperature box, heating the hot stress test bench and the pipeline to be tested; measuring the heated bearing platform 12, more specifically, measuring the deformation △L of the bearing fixture 4, such as Figure 6 The difference L' between the casing deformation spacing L and the flange base deformation △L is set as the correction spacing between the flange base 3 and the baffle 24.

[0043] If the load-bearing fixture 4 does not undergo thermal deformation, Figure 5 The theoretical casing deformation spacing L from the middle flange base 3 to the baffle 24 is equal to the engine casing deformation N, that is, the theoretical displacement loading value. Since the bearing fixture 4 is thermally deformed at high temperature, the actual deformation of the pipeline 9 to be tested becomes larger. Therefore, it is necessary to measure and eliminate the additional thermal deformation ΔL caused by the deformation of the bearing fixture 4, and reset the corrected gap value L' to meet the stress distribution of the pipeline in the real environment of the engine, that is, L'=L-△L.

[0044] In this way, when the pipeline hot stress test bench is heated under the corrected spacing, the deformation N of the pipeline 9 to be tested is equal to the corrected spacing L' plus the deformation △L of the load-bearing fixture 4 itself, which still meets the requirement of N=L. Under this requirement, the actual deformation of the pipeline is the true deformation, thereby measuring a more accurate stress distribution.

[0045] The deformation ΔL of the load-bearing fixture 4 is obtained by using a triangle ruler 30 and a vernier caliper (not shown in the figure), as shown in FIG. Figure 6 As shown, since the bottom of the support fixture 4 is cooled by the water-cooled bottom plate 7, it can be considered that the bottom of the support fixture 4 does not deform, but the top of the connecting flange base 3 deforms, causing the left side of the support fixture 4 to tilt. Use a triangle ruler 30 to press against the maximum deformation M of the support fixture 4, and use a vernier caliper to measure the distance between the triangle ruler 30 and the point P where the support fixture 4 is connected to the water-cooled bottom plate 7 to obtain the deformation △L of the support fixture 4.

[0046] The specific steps of the correction method are as follows.

[0047] like Figure 5As shown, when the thermal stress test bench is assembled, the fixed bottom plate 8 is used as the reference plane, and the square ruler 30 is used as the ruler to make the baffle 24 and the left side of the bearing fixture 4 flush.

[0048] During the test debugging stage, the test tooling is placed in a high-temperature furnace, heated to the specified test temperature, and maintained for at least 30 minutes to allow the test tooling to be fully heated through.

[0049] After heating, Figure 6 As shown, with the bottom plate 8 as the reference plane, a square ruler 30 is used to approach the end of the displacement loading bolt 2 passing through the baffle 24. Due to the thermal deformation of the load-bearing fixture 4, there is a gap between the square ruler 30 and the load-bearing fixture 4. The gap △L between the bottom of the square ruler and the test fixture is measured with a vernier caliper, which is the thermal deformation of the load-bearing fixture 4.

[0050] Combined with the introduction of the above-mentioned pipeline thermal stress test correction method, it can also be connected to a pipeline thermal stress test method. First, the distance between the flange base and the baffle is corrected by the above-mentioned correction method, and then the thermal stress test bench is set in a high temperature box, and the thermal stress test bench and the pipeline to be tested are heated to measure the stress of the pipeline to be tested, thereby obtaining more accurate pipeline stress data.

[0051] The present application uses specific words to describe the embodiments of the present application. For example, "one embodiment", "an embodiment", and / or "some embodiments" refer to a certain feature, structure or characteristic related to at least one embodiment of the present application. Therefore, it should be emphasized and noted that "one embodiment" or "an embodiment" or "an alternative embodiment" mentioned twice or multiple times in different positions in this specification does not necessarily refer to the same embodiment. In addition, some features, structures or characteristics in one or more embodiments of the present application can be appropriately combined.

[0052] Although the present invention is disclosed as above with preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art may make possible changes and modifications without departing from the spirit and scope of the present invention. Therefore, any modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention shall fall within the protection scope defined by the claims of the present invention.

Claims

1. Pipeline thermal stress test bench, used for thermal stress test of pipeline to be tested, characterized by: include: Base plate; A pair of bearing platforms, arranged on the bottom plate, respectively used to bear the two ends of the pipeline to be tested; A pair of flange bases are arranged on the top of the bearing platform and are respectively used to fix the two ends of the pipeline to be tested, one of the flange bases is fixedly connected to the bearing platform, and the other one is arranged to be movable along the axial direction of the pipeline to be tested relative to the bearing platform; Wherein, the bearing platform is also provided with a baffle for limiting the maximum moving distance of the flange base.

2. The pipeline thermal stress test bench according to claim 1, characterized in that: The flange base is movably connected to the bearing platform via a linear bearing.

3. The pipeline thermal stress test bench according to claim 1, characterized in that: The supporting platform includes a water-cooled base plate and a supporting tooling. The water-cooled base plate is provided with a water circulation channel and is fixedly connected to the bottom of the base plate. The supporting tooling includes block parts and / or plate parts and / or columnar parts that are detachably connected to each other.

4. The pipeline thermal stress test bench according to claim 3, characterized in that: The bearing platform also includes a displacement loading bolt that passes through the baffle, and the displacement loading bolt is used to be fixedly connected to the flange base.

5. The pipeline thermal stress test bench according to claim 1, characterized in that: The flange base is detachably fixedly connected to the bearing platform.

6. Pipeline thermal stress test system, characterized in that: include: high temperature box; According to the thermal stress test bench as described in any one of claims 1 to 5, the flange base and the pipeline to be tested of the thermal stress test bench are arranged in the high temperature box.

7. The pipeline thermal stress test system according to claim 6, characterized in that: The system also includes a temperature controller, a temperature recorder, and a temperature sensor.

8. The pipeline thermal stress test system according to claim 6, characterized in that: The system also includes a high temperature strain gauge attached to the pipeline to be tested.

9. The pipeline thermal stress test correction method is characterized by: The method is carried out using a thermal stress test system as described in any one of claims 6 to 8, and comprises the following steps: Determine the theoretical casing deformation spacing; The thermal stress test bench is placed in a high temperature box to heat the thermal stress test bench and the pipeline to be tested; Measure the deformation of the bearing platform after heating; The difference between the casing deformation distance and the flange base deformation is set as the correction distance between the flange base and the baffle.

10. Pipeline thermal stress test method, characterized in that: First, the pipeline thermal stress test correction method as described in claim 9 is performed to correct the distance between the flange base and the baffle; The thermal stress test bench is arranged in a high temperature box, the thermal stress test bench and the pipeline to be tested are heated, and the stress of the pipeline to be tested is measured.

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