A device and method for testing the micro-motion life of a turbine tenon connection structure

Abstract

The present invention discloses a device and method for testing the micro-motion life of a turbine tenon connection structure; the device includes a frame, an exciter, a tenon fixture, a tenon fixing fixture, and a tenon anti-deformation fixture. The tenon anti-deformation fixture is located between the tenon fixing fixture and the tenon fixture. Two restraint blocks are provided in the tenon anti-deformation fixture. During operation, the tenon member and the tenon member are assembled together; the tenon member is located between the two restraint blocks of the tenon anti-deformation fixture; the exciter drives the tenon member to vibrate, and the two restraint blocks restrain the deformation of the tenon member along the width direction of the tenon. The present invention provides a tenon anti-deformation fixture on the outside of the rectangular tenon block to restrain the deformation of the tenon block along the width direction of the groove during the test, thereby simulating the stress and deformation of the actual turbine disk tenon structure and improving the accuracy of the turbine disk tenon life detection. At the same time, the present invention improves the stability of the fixture through a multi-point fixing structure and improves the follow-up capability by optimizing the fixture geometry.

Description

Technical Field

[0001] The present invention relates to the technical field of material performance testing, and in particular to a device and method for testing the micro-motion life of a turbine tenon connection structure. Technical Background

[0002] In the aviation field, the tenon structure of the turbine disk in an aero-engine is a vital component that is used to ensure a secure connection and operational stability between components. Currently, micro-motion fatigue testing technology is widely used to evaluate the quality and reliability of tenon structures. However, there is still room for improvement in improving the accuracy and reliability of tenon structure testing, and further research and development are needed to enhance this testing method. With the growing demand for tenon connections in the aerospace manufacturing industry, higher requirements are placed on the load-bearing capacity of tenon connection structures under dynamic loads. Under harsh and complex service conditions, tenon connection structures are more susceptible to surface damage and defects, such as fatigue cracks, wear, looseness, and fracture, when subjected to axial micro-motion. These surface damage and defects generated by tenon connection structures during service can lead to their failure or even cause more serious structural problems.

[0003] To ensure the reliability and longevity of tenon joints, axial micro-motion life tests must be conducted using specialized test fixtures to simulate actual operating conditions and study their performance under dynamic loads. During these tests, tenon joints are subjected to periodic micro-motion loads, which cause friction and wear on the contact surfaces, leading to degradation of material properties. Improper experimental design and operation can exacerbate this degradation, compromising the accuracy and reliability of the test results.

[0004] Fretting refers to the extremely small movement between the surfaces of two contacting objects, with the displacement amplitude generally ranging from tens to over a hundred microns. Fretting fatigue refers to the phenomenon in which, under cyclic loading, a small relative sliding occurs between a portion of a component surface and other contact surfaces, resulting in a reduction in the component's fatigue strength or premature fracture. It is a general term for wear and induced fatigue fracture caused by small-amplitude relative tangential vibrations between contact surfaces. Fretting fatigue includes fretting wear and fretting fatigue caused by crack initiation and propagation under alternating stress, leading to fracture. In order to better analyze the fretting fatigue behavior of materials and reveal the damage and failure mechanisms of materials, material-level fretting fatigue testing has received increasing attention.

[0005] In particular, micro-motion experiments on the tenon structure of a turbine disk are particularly challenging. In actual operating environments, the tenons and grooves in a turbine disk are evenly distributed in a circular array on the disk, and after the tenons and grooves are assembled, the load is evenly distributed on the outer surface of the disk. However, most experiments use a simplified single-tenon and groove test block to simulate the turbine disk. During the experiment, the tenon and groove components are isolated and unsupported at both ends, making them prone to bilateral expansion deformation. However, an actual turbine disk has a circle of tenons, all of which are equipped with tenons, leaving no room for bilateral expansion deformation. This results in significant differences between the experimental test conditions and actual operating conditions, leading to large experimental errors and seriously affecting the reliability of the experiment and the accuracy of the experimental data.

[0006] Therefore, there is an urgent need to develop a simple, safe, and reliable fixture for the axial micro-motion life test of tenon joints, along with a research method, that can accurately simulate axial micro-motion conditions. This fixture should provide precise micro-motion load control, synchronize with the motion of the specimen, possess sufficient stability, and ensure uniform and consistent load transfer. Furthermore, it should be able to control radial deformation of the tenon groove during the experiment, providing a scientific basis for design and maintenance in practical applications. Summary of the Invention

[0007] To overcome the shortcomings of existing research, this paper establishes a static simulation model of mortise-jointed structural components, conducts simulation analysis and prediction of component stress and deformation, and designs a fixture for axial micro-motion life testing of mortise-jointed structural components based on the simulation results. This paper provides a fixture and research method for axial micro-motion life testing of mortise-jointed structural components that can synchronously follow the movement of the sample, provide precise micro-motion load control, possess sufficient stability to ensure uniform and consistent load transfer, and simultaneously control radial load deformation of the mortise groove during the experiment.

[0008] In a first aspect, a micro-vibration life test device for a turbine tenon joint structure includes a frame, a vibration exciter, a tenon fixture, a tenon-groove fixing fixture, and a tenon-groove anti-deformation fixture mounted on the frame. The vibration exciter is fixed to the bottom of the frame. The tenon fixture is mounted on the vibration output shaft at the top of the vibration exciter and is used to mount the tenon. The tenon-groove fixing fixture is fixed to the top of the frame and is used to mount the tenon-groove.

[0009] The mortise and tenon anti-deformation fixture is located between the mortise and tenon fixing fixture and the tenon fixture. The mortise and tenon anti-deformation fixture is provided with two restraint blocks. The two restraint blocks are opposite to each other and spaced apart.

[0010] During operation, the tenon and the mortise are assembled together; the tenon is located between the two restraint blocks of the mortise anti-deformation fixture; the vibrator drives the tenon to vibrate, and the two restraint blocks restrain the deformation of the mortise along the width direction of the mortise.

[0011] Preferably, the two ends of the mortise and tenon piece to be measured are respectively provided with the mortise and tenon structure to be measured and mounting threaded holes. The two ends of the tenon piece are respectively provided with the tenon structure to be measured and mounting studs.

[0012] Preferably, the tenon fixture comprises a mounting base, a connecting tube, and two half-fastening sleeves. A guide shaft is provided at the bottom of the mounting base. The guide shaft is slidably connected to a guide hole in the vibrator. The connecting tube is integrally formed on the top surface of the mounting base. The connecting tube has a vertical axis and an inner sidewall with internal threads.

[0013] Two symmetrically arranged half-clamping sleeves enclose the outer side of the connecting tube. The half-clamping sleeves comprise an integrally formed half-sleeve and a tenon support bracket. The tenon support bracket is located on the convex side of the top of the half-sleeve. A radially arranged first pin hole is defined in the sidewall of the connecting tube. The tenon support bracket is provided with a groove structure that mates with the bottom of the main body of the tenon being measured. A corner notch is provided on the bottom edge of the tenon support bracket, facing away from the half-sleeve.

[0014] During operation, the mounting stud on the tenon is threadedly connected to the internal thread of the connecting tube; the second pin hole on the tenon is connected to the first pin hole on the connecting tube via a pin. The bottom of the main body of the tenon is embedded in the groove structure of the tenon support bracket.

[0015] Preferably, the half-clamping sleeve further includes a first ear and a second ear. The first ear is provided on both side edges of the half-sleeve. The first ear of each half-clamping sleeve is secured by bolts, and the second ear is provided on the bottom edge of each half-sleeve. The second ear is aligned with the top surface of the mounting base and secured by bolts, so that the two half-sleeves together form a complete sleeve structure that is sleeved onto the outside of the connecting sleeve.

[0016] Preferably, the half sleeve is fixed to the connecting sleeve by bolts. The bottom and side of the tenon piece are both connected to the tenon support bracket by bolts.

[0017] Preferably, the frame comprises a bottom plate and a top plate; the height and level of the top plate relative to the bottom plate are adjustable; the exciter is mounted on the bottom plate; and the tongue and groove fixing fixture is mounted on the bottom surface of the top plate.

[0018] Preferably, the mortise and tenon anti-deformation fixture includes an integrally formed outer frame, a first anti-bending support beam, an intermediate support ring, a second anti-bending support beam and two constraint blocks. The outer frame is mounted on a frame. The intermediate support ring is spaced apart on the inner side of the outer frame and is connected to the inner side wall of the outer frame through the first anti-bending support beam. Two constraint blocks are arranged on the inner side of the intermediate support ring. The opposite sides of the two constraint blocks are connected to the inner side wall of the intermediate support ring through the second anti-bending support beam. Constraint grooves are provided on the opposite sides of the two constraint blocks. During operation, the mortise and tenon piece is located between the two constraint blocks, and the two side surfaces of the mortise and tenon piece are in contact with the bottom surfaces of the constraint grooves of the two constraint blocks respectively.

[0019] Preferably, the frame further comprises an adjustment column and a guide rail. The bottom ends of the plurality of vertically arranged guide rails are fixed at different positions on the top surface of the base plate. A plurality of adjustment columns are evenly arranged around each guide rail. The bottom ends of all the adjustment columns are fixed to the top surface of the base plate. The top plate is provided with clearance holes corresponding to the guide rails and adjustment holes corresponding to the adjustment columns. The aperture of the adjustment hole is larger than the diameter of the adjustment column. The top of the adjustment column is an adjustment section with an external thread. The adjustment section of the adjustment column passes through the corresponding adjustment hole. The adjustment column and the top plate are fixed by two nuts located on the upper and lower sides of the top plate respectively. The levelness of the top plate is adjusted by adjusting the height of the nuts on each adjustment column. A plurality of guide sleeves are provided on the outer frame; the guide sleeves are slidably connected to the guide rails in the frame and are locked at a plurality of different positions.

[0020] Preferably, the guide rail and the adjustment column are both cylindrical, and the diameter of the guide rail is larger than the diameter of the adjustment column.

[0021] Preferably, the mortise and tenon fixture is secured to the bottom surface of the top plate via a plurality of bolts; a connecting stud is provided at the bottom of the mortise and tenon fixture; and a fastening screw is threadedly connected to the mortise and tenon fixture, extending axially through the connecting stud. During operation, the threaded mounting hole of the mortise and tenon fixture is threadedly engaged with the connecting stud. The end of the fastening screw abuts against the bottom end of the threaded mounting hole of the mortise and tenon fixture.

[0022] In a second aspect, the present invention provides a method for testing the life of a turbine tenon connection structure using the aforementioned device for testing the life of a turbine tenon connection structure. The method comprises the following steps:

[0023] Step 1: Install the tenon fixture on the vibrator and fix the tenon piece on the tenon fixture.

[0024] Step 2: Install the two half fastening sleeves around the outside of the connecting tube, and make the corners of the tenon piece be in the corner notch structure of the tenon support bracket.

[0025] Step 3: Assemble the mortise and tenon parts together.

[0026] Step 4: Adjust the position of the mortise and tenon anti-deformation fixture so that the mortise and tenon piece is between the two constraint blocks, and fix the position of the mortise and tenon anti-deformation fixture.

[0027] Step 5. Fix the mortise and tenon piece to the mortise and tenon fixing fixture; adjust the position of the top plate and fix it; fix the mortise and tenon fixing fixture to the top plate so that the mortise and tenon piece remain coaxial.

[0028] Step 6: Start the vibrator to make the tenon part move up and down slightly to simulate the actual working condition of the tenon connection structure in the turbine. According to the damage of the tenon part or the mortise part, the life of the turbine tenon connection structure is judged.

[0029] The beneficial effects of the present invention are:

[0030] This invention addresses the difficulty of maintaining a consistently centered specimen during current axial micro-motion life tests on mortise-jointed structural components, as well as the tendency for specimens to shift or rotate during the test. This method proposes a method for improving fixture stability through a multi-point fixation structure, thereby enhancing both experimental reliability and the accuracy of experimental data. Furthermore, by installing a mortise anti-deformation fixture on the exterior of a rectangular mortise block, the invention constrains deformation of the block along the slot width during testing, simulating the stress and deformation of a real turbine disk mortise structure and improving the accuracy of turbine disk mortise life tests.

[0031] In view of the problems that samples are difficult to align and samples and test benches are prone to follow-up in the current axial micro-motion life test of mortise and tenon joint structural parts, the present invention proposes a method to improve the follow-up capability by optimizing the geometric structure of the fixture to ensure the uniformity and consistency of load transfer.

[0032] This paper addresses the instability of fixtures during current axial micro-motion life tests for tenon-jointed structural components. This paper proposes a design method for optimizing the fixture structure by using a static simulation model of tenon-jointed structural components and prediction of micro-motion deformation. Furthermore, this paper addresses the uneven loading of axial loads during current axial micro-motion life tests for tenon-jointed structural components. This paper proposes a design method for optimizing the fixture structure by using a static simulation model of tenon-jointed structural components and prediction of equivalent stress. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0034] Figure 1This is a schematic diagram of the overall structure of Example 1 of the present invention.

[0035] Figure 2 Schematic diagram of the connection between the tongue and groove anti-deformation fixture and the frame in Example 1 of the present invention.

[0036] Figure 3 This is a structural schematic diagram of the mortise and tenon anti-deformation fixture and the mortise and tenon fixing fixture for clamping the mortise and tenon parts in Example 1 of the present invention.

[0037] Figure 4 This is a schematic structural diagram of the tenon clamp in Example 1 of the present invention.

[0038] Figure 5 This is a schematic diagram of the assembly of the tenon clamp and the tenon fixture in Example 1 of the present invention.

[0039] Figure 6 Schematic diagram of mesh division of the simulation model of the present invention.

[0040] Figure 7 1 is a comparison cloud diagram of the total deformation of the simulation of Example 1 of the present invention and Comparative Example 1.

[0041] Figure 8 2 is a comparison cloud diagram of the simulated equivalent stress between Example 1 of the present invention and Comparative Example 1.

[0042] In the figure: 100-frame; 101-base plate; 102-adjusting column; 103-guide rail; 104-top plate; 200-vibrator; 300-tenon fixture; 310-mounting seat; 311-first pin hole; 312-sleeve connecting screw hole; 320-semi-fastening sleeve; 321-first through hole; 330-connecting tube; 400-tenon and groove fixing fixture; 500-tenon and groove part; 600-tenon and groove anti-deformation fixture; 700-tenon part. DETAILED DESCRIPTION

[0043] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0044] Example 1

[0045] A device for testing the micro-motion life of a turbine tenon connection structure is provided, which is used to test the micro-motion life of the cooperation between the tenon member 700 and the tenon groove member 500, thereby testing the connection reliability and service life of the turbine disk and blade connected by the tenon structure. In this embodiment, the tenon groove member 500 to be tested is in the shape of a rectangular parallelepiped; the tenon groove structure to be tested and the mounting threaded holes for connecting the fixture are respectively provided at both ends of the tenon member 700. The tenon structure to be tested and the mounting studs for connecting the fixture are respectively provided at both ends of the tenon member 700. Therefore, the tenon member 700 can be divided into a main body portion for providing the tenon structure and the mounting studs.

[0046] The micro-motion life test device of the turbine tenon connection structure includes a frame 100, and an exciter 200, a tenon clamp 300, a tenon fixing clamp 400 and a tenon anti-deformation clamp 600 installed on the frame 100. The exciter 200 is fixed to the bottom of the frame 100. The tenon clamp 300 is installed on the vibration output shaft at the top of the exciter 200 and is used to clamp the tenon part 700. The tenon fixing clamp 400 is fixed to the top of the frame 100 and is used to fix the tenon part 500. The tenon anti-deformation clamp 600 is located between the tenon fixing clamp 400 and the tenon clamp 300 and is used to constrain the deformation of the tenon part 500 along the width direction.

[0047] The rack 100 includes a base plate 101, adjustment columns 102, guide rails 103, and a top plate 104. The bottom ends of four vertical guide rails 103 are fixed to the four corners of the top surface of the base plate 101. Four adjustment columns 102 are evenly spaced around the guide rails 103. The bottom ends of all adjustment columns 102 are fixed to the top surface of the base plate 101. Both the guide rails 103 and the adjustment columns 102 are cylindrical, with the diameter of the guide rails 103 being larger than that of the adjustment columns 102.

[0048] The top plate 104 is provided with four clearance holes corresponding to the four guide rails 103, and sixteen adjustment holes corresponding to the sixteen adjustment columns 102. The diameter of the adjustment hole is larger than the diameter of the adjustment column 102. The top of the adjustment column 102 is an adjustment section with an external thread. The adjustment section of the adjustment column 102 passes through the corresponding adjustment hole. The adjustment column 102 and the top plate 104 are fixed by two nuts located on the upper and lower sides of the top plate 104 respectively. By adjusting the position of the nuts on each adjustment column 102, the horizontality of the top plate 104 can be adjusted. At the same time, it is also ensured that the top plate 104 has sufficient assembly accuracy to ensure that the mortise and tenon fixing fixture 400 and the mortise and tenon part 500 are in the center position.

[0049] The mortise and tenon fixture 400 is secured to the bottom surface of the top plate 104 via multiple bolts. During operation, the threaded mounting holes on the mortise and tenon member 500 are threadedly engaged with the connecting studs at the bottom of the mortise and tenon fixture 400, securing the mortise and tenon member 500. The mortise and tenon fixture 400 is equipped with a fastening screw that passes through the connecting studs and abuts against the bottom of the threaded mounting holes on the mortise and tenon member 500.

[0050] The tongue-and-groove anti-deformation fixture 600 includes an integrally formed outer frame 602, a first anti-bending support beam 603, an intermediate support ring 605, a second anti-bending support beam 604, and two restraint blocks 601. Guide sleeves are provided at each of the four corners of the outer frame; the four guide sleeves are slidably connected to the four guide rails 103 in the frame 100 and can be locked at any position (the locking method is a set screw or a locking claw structure). The intermediate support ring is spaced apart on the inner side of the outer frame and connected to the inner side wall of the outer frame via the first anti-bending support beam. Two restraint blocks facing each other are provided on the inner side of the intermediate support ring. The opposite sides of the two restraint blocks are connected to the inner side wall of the intermediate support ring via the second anti-bending support beam.

[0051] Constraint grooves are defined on opposing sides of the two constraint blocks. During operation, the mortise and tenon member 500 lies between the two constraint blocks, with its sides contacting the bottom surfaces of the constraint grooves in each of the two constraint blocks. The alignment of the two constraint blocks aligns with the groove width of the mortise and tenon member 500, enabling them to constrain the mortise and tenon member 500 during testing, suppressing expansion and deformation along the groove width during testing. This ensures that the testing process more closely matches the actual operating conditions of the turbine disk mortise and tenon.

[0052] The tenon fixture 300 includes a mounting base 310, a connecting tube 330, and two half-fastening sleeves 320. Four guide shafts are located at the bottom of the mounting base 310. These guide shafts are slidably connected to the four guide holes on the vibrator 200. The middle portion of the bottom surface of the mounting base 310 is fixed to the vibration output shaft of the vibrator 200.

[0053] The connecting tube 330 is integrally formed at the center of the top surface of the mounting base 310. The axis of the connecting tube 330 is set vertically, and the inner side wall is provided with an internal thread. Two symmetrically arranged half-fastening sleeves 320 are enclosed on the outside of the connecting tube 330. The half-fastening sleeve 320 includes an integrally formed half-sleeve 323, a first ear 325, a tenon support bracket 322 and a second ear 324 fixed to the mounting base 310. The first ear 325 is provided on both side edges of the half-sleeve 323. The first ear 325 in the two half-fastening sleeves 320 fit together and are fixed by bolts, so that the two half-sleeves 323 are enclosed to form a complete sleeve structure that is sleeved on the outside of the connecting tube 330. A plurality of second ears 324 are provided on the bottom edge of the half-sleeve 323. The second ears 324 fit on the top surface of the mounting base 310 and are fixed by bolts.

[0054] The sidewall of the connecting cylinder 330 is provided with a radially arranged first pin hole 311 and a sleeve connecting screw hole 312. Each half sleeve 323 is provided with a first through hole 321. The first through hole 321 on the half sleeve 323 is aligned with the sleeve connecting screw hole 312 of the connecting cylinder 330 and is fixed by bolts.

[0055] The tenon support bracket 322 is a rectangular thin-walled part, which is located on the convex side of the top of the half sleeve 323. The tenon support bracket 322 is used to support and constrain the main part of the tenon member 700. The tenon support bracket 322 is provided with a groove structure that matches the bottom of the main part of the tenon member 700 to be measured. The bottom of the tenon support bracket 322 is provided with a corner notch structure at the edge facing away from the half sleeve 323. The corner notch structure can expose the corners of the main part of the tenon member 700 to avoid interference between the tenon member 700 to be measured and the fixture and the occurrence of unevenness in load transfer, so as to ensure that the tenon member 700 always maintains a good and accurate position during the experiment.

[0056] A second through hole and a third through hole are respectively formed on the bottom surface of the tenon support bracket 322 and the side surface furthest from the half-sleeve 323. A second pin hole is radially disposed on the mounting stud of the tenon member 700 being tested. Threaded holes are also formed on the main body of the tenon member 700 being tested at positions corresponding to the second and third through holes of the tenon support bracket 322.

[0057] During operation, the mounting stud on the tenon 700 is threadedly engaged with the internal thread of the connecting tube 330. The second pin hole on the tenon 700 is aligned with the first pin hole 311 on the connecting tube 330 and connected via a pin, ensuring that the tenon 700 and the mounting base 310 are fully locked and move synchronously. Simultaneously, the bottom of the main body of the tenon 700 is embedded in the groove structure of the tenon support bracket 322. The threaded hole in the main body of the tenon 700 is connected to the second and third through holes of the tenon support bracket 322 via bolts.

[0058] The testing method of the turbine tenon connection structure micro-motion life testing device comprises the following steps:

[0059] Step 1: Install the tenon fixture 300 on the exciter 200, and fix the tenon piece 700 to the connecting tube 330 of the tenon fixture 300 through a threaded connection, and use a pin to connect the second pin hole on the tenon piece 700 and the first pin hole 311 on the connecting tube 330 to ensure that the tenon piece 700 and the connecting tube 330 are completely locked and can follow the movement synchronously.

[0060] Step 2: Assemble the two half-fastening sleeves 320 on either side of the connecting tube 330 and the tenon 700, aligning the corners of the tenon 700 with the corner notches of the tenon support bracket 322 of the half-fastening sleeve 320. Bolt the second and third through-holes of the tenon support bracket 322 to the corresponding threaded holes in the tenon 700. Bolt the first through-hole 321 of the half-sleeve 323 to the sleeve connection threaded hole 312 on the connecting tube 330. Bolt the second ear 324 at the bottom of the half-fastening sleeve 320 to the mounting base 310.

[0061] Step 3: Lock the mortise and tenon deformation prevention fixture 600 on the guide rail 103. Assemble the mortise and tenon structure of the mortise and tenon member 500 and the tenon structure of the tenon member 700.

[0062] Step 4: Pass the mortise and tenon piece through the two restraint blocks in the mortise and tenon anti-deformation fixture 600; then fine-tune and fix the position of the mortise and tenon anti-deformation fixture 600.

[0063] Step 5: Fix the mortise and tenon piece 500 to the mortise and tenon fixing fixture 400 through threaded connection, adjust the position of the top plate, and fix the mortise and tenon fixing fixture to the top plate through bolts; after adjusting the position, fix the top plate in position through the nuts on each adjustment column 102.

[0064] Step 6. Use the fastening screw to pass through the through hole reserved in the center of the top plate, screw it into the threaded hole on the mortise and tenon fixing fixture 400 that passes through the stud, and press against the bottom end of the installation threaded hole of the mortise and tenon part 500 to ensure that the position of the mortise and tenon part 500 is fixed and not easy to slip during the experiment.

[0065] Step 7: Start the vibrator to make the tenon 700 perform high-frequency reciprocating micro-movement up and down to simulate the actual working conditions of the tenon connection structure in the turbine; thereby obtaining the service life of the tenon connection structure.

[0066] Comparative Example 1

[0067] A micro-motion life test device for a turbine tenon connection structure. The difference between this comparative example and Example 1 is that no tenon groove anti-deformation fixture 600 is provided, and no pin shaft and two half-fastening sleeves 320 are provided in the tenon fixture 300.

[0068] In order to prove the effect of improving the test accuracy of Example 1, a simulation comparison experiment was conducted on the test devices provided in Example 1 and Comparative Example 1. The experiment used the Ansys Workbench simulation integration platform and the Static Structural analysis system to establish a static simulation model of the mortise and tenon joint structural member. The mesh setting used tetrahedron as the main unit form, the minimum edge length of 0.0056m was set to 0.000237m, the span angle center was set to large scale, the expansion algorithm used pre-position, smooth transition, transition ratio set to 0.272, and growth rate set to 1.2; the simulation model mesh generation diagram of the experiment is shown in FIG. Figure 6 shown.

[0069] Set the Solver Target to Mechanical APDL and the Solver Unit System to MKS. Calculate the total deformation and equivalent stress of the specimen under different loading forms. In post-processing, set the contour plot to display the undeformed border as a contour band.

[0070] The comparison of the total deformation simulation results of the samples of Example 1 (corresponding to the right figure) and Comparative Example 1 (corresponding to the left figure) is as follows: Figure 7 As shown; by observation Figure 7 It can be clearly observed that the deformation of the sample model after being constrained by the fixture in Example 1 is more symmetrical and uniform, and the mortise and tenon parts have no deformation in the groove width direction; this shows that the fixture in the test device provided in Example 1 can synchronously follow the movement of the sample, has sufficient stability, and is a fixture for the axial micro-motion life test of mortise and tenon connection structural parts that ensures the clamping accuracy of the sample and the stability of the experimental process.

[0071] The comparison of the equivalent stress simulation results of the samples of Example 1 (corresponding to the right figure) and Comparative Example 1 (corresponding to the left figure) is as follows: Figure 8 As shown. By observing Figure 8 It can be clearly observed that the equivalent (Von-Mises) stress of the sample after being constrained by the fixture in Example 1 is smaller, the maximum stress (stress concentration singular point) is reduced by about 27%, the minimum stress (dark blue area) is more widely distributed, the stress contour band shows a more uniform shape, and the transition is smoother; this shows that the fixture in the test device provided in Example 1 can ensure that the load transferred in the sample is smaller and more uniform, the overall transfer process is more stable, and it is a fixture for the axial micro-motion life test of tenon-jointed structural parts that ensures the uniformity and consistency of load transfer.

[0072] The embodiments of the present invention are described in detail above with reference to the accompanying drawings, but the present invention is not limited to the described embodiments. It is apparent to those skilled in the art that various changes, modifications, substitutions, and variations to these embodiments may be made without departing from the principles and spirit of the present invention, and these changes and modifications still fall within the scope of protection of the present invention.

Claims

1. A micro-motion life test device for a turbine tenon connection structure, comprising a frame (100), an exciter (200), a tenon fixture (300), and a tenon groove fixing fixture (400) mounted on the frame (100); characterized in that: It also includes a tenon and groove anti-deformation fixture (600); the vibrator (200) is fixed to the bottom of the frame (100); the tenon fixture (300) is installed on the vibration output shaft at the top of the vibrator (200) and is used to install the tenon piece (700); the tenon and groove fixing fixture (400) is fixed to the top of the frame (100) and is used to install the tenon and groove piece (500); The frame (100) includes a bottom plate (101) and a top plate (104); the height and levelness of the top plate (104) relative to the bottom plate (101) can be adjusted; the exciter (200) is mounted on the bottom plate (101); and the tongue and groove fixing fixture (400) is mounted on the bottom surface of the top plate (104); The mortise and tenon anti-deformation fixture (600) is located between the mortise and tenon fixing fixture (400) and the tenon head fixture (300); two restraint blocks (601) are provided in the mortise and tenon anti-deformation fixture (600); the two restraint blocks (601) are opposite to each other and are spaced apart; The mortise and tenon anti-deformation fixture (600) comprises an integrally formed outer frame (602), a first anti-bending support beam (603), an intermediate support ring (605), a second anti-bending support beam (604) and two constraint blocks (601); the outer frame is mounted on a machine frame; the intermediate support ring is spaced apart on the inner side of the outer frame and connected to the inner side wall of the outer frame via the first anti-bending support beam; the two constraint blocks are arranged on the inner side of the intermediate support ring; the opposite sides of the two constraint blocks are connected to the inner side wall of the intermediate support ring via the second anti-bending support beam; constraint grooves are provided on the opposite sides of the two constraint blocks; during operation, the mortise and tenon member (500) is located between the two constraint blocks, and the two side surfaces of the mortise and tenon member (500) are in contact with the bottom surfaces of the constraint grooves of the two constraint blocks respectively; During operation, the tenon piece (700) and the tenon groove piece (500) are assembled together; the tenon piece (700) is located between two restraining blocks (601) of the tenon groove anti-deformation fixture (600); the vibrator (200) drives the tenon piece (700) to vibrate, and the two restraining blocks (601) restrain the deformation of the tenon groove piece (500) along the width direction of the tenon groove.

2. A turbine tenon connection structure micro-motion life test device according to claim 1, characterized in that: The two ends of the measured mortise and tenon part (500) are respectively provided with the measured mortise and tenon structure and mounting threaded holes; the two ends of the tenon part (700) are respectively provided with the measured tenon structure and mounting studs.

3. The micro-vibration life test device for a turbine tenon connection structure according to claim 2, characterized in that: The tenon clamp (300) includes a mounting seat (310), a connecting tube (330) and two half-fastening sleeves (320); a guide shaft is provided at the bottom of the mounting seat (310); the guide shaft is slidably connected to the guide hole on the exciter (200); the connecting tube (330) is integrally formed on the top surface of the mounting seat (310); the axis of the connecting tube (330) is vertically arranged, and the inner side wall is provided with an internal thread; Two symmetrically arranged half-fastening sleeves (320) are enclosed on the outside of the connecting tube (330); the half-fastening sleeve (320) includes an integrally formed half-sleeve (323) and a tenon support bracket (322); the tenon support bracket (322) is located on the convex side of the top of the half-sleeve (323); the side wall of the connecting tube (330) is provided with a radially arranged first pin hole (311); the tenon support bracket (322) is provided with a groove structure that matches the bottom of the main part of the tenon member (700) to be measured; the bottom of the tenon support bracket (322) is provided with a corner notch structure at the edge away from the half-sleeve (323); During operation, the mounting stud on the tenon member (700) is threadedly connected to the internal thread of the connecting tube (330); the second pin hole provided on the tenon member (700) is connected to the first pin hole (311) on the connecting tube (330) via a pin; and the bottom of the main body of the tenon member (700) is embedded in the groove structure of the tenon support bracket (322).

4. The micro-vibration life test device for a turbine tenon connection structure according to claim 3, characterized in that: The semi-fastening sleeve (320) further includes a first ear (325) and a second ear (324); the first ear (325) is provided on both side edges of the semi-sleeve (323); the first ear (325) in the two semi-fastening sleeves (320) is fixed by bolts, and the second ear (324) is provided on the bottom edge of the semi-sleeve (323); the second ear (324) is affixed to the top surface of the mounting seat (310) and fixed by bolts, so that the two semi-sleeves (323) are combined to form a complete sleeve structure that is sleeved on the outside of the connecting sleeve (330).

5. The micro-vibration life test device for a turbine tenon connection structure according to claim 3 is characterized in that: The half sleeve (323) and the connecting cylinder (330) are fixed by bolts; the bottom and side of the tenon member (700) are connected to the tenon support bracket (322) by bolts.

6. The micro-vibration life test device for a turbine tenon connection structure according to claim 1, characterized in that: The rack (100) further comprises an adjustment column (102) and a guide rail (103); the bottom ends of the plurality of vertically arranged guide rails (103) are respectively fixed at different positions on the top surface of the bottom plate (101); a plurality of adjustment columns (102) are evenly surrounded on all sides of each guide rail (103); the bottom ends of all the adjustment columns (102) are fixed to the top surface of the bottom plate (101); the top plate (104) is provided with a clearance hole corresponding to the guide rail (103) and an adjustment hole corresponding to the adjustment column (102); the aperture of the adjustment hole is large. The diameter of the adjusting column (102) is adjusted; the top of the adjusting column (102) is an adjusting section provided with an external thread; the adjusting section of the adjusting column (102) passes through the corresponding adjusting hole; the adjusting column (102) and the top plate (104) are fixed by two nuts respectively located on the upper and lower sides of the top plate (104); the horizontality of the top plate (104) is adjusted by adjusting the height of the nuts on each adjusting column (102); a plurality of guide sleeves are provided on the outer frame; the guide sleeves are slidably connected to the guide rails (103) in the frame (100) and are locked at a plurality of different positions.

7. The micro-motion life test device for a turbine tenon connection structure according to claim 1, characterized in that: The mortise and tenon fixing fixture (400) is fixed to the bottom surface of the top plate (104) by a plurality of bolts; a connecting stud is provided at the bottom of the mortise and tenon fixing fixture (400); a fastening screw is threadedly connected to the mortise and tenon fixing fixture (400) and passes through the connecting stud in the axial direction; during operation, the mounting threaded hole of the mortise and tenon member (500) is threadedly connected to the connecting stud of the connecting stud; the end of the fastening screw abuts against the bottom end of the mounting threaded hole of the mortise and tenon member (500).

8. A method for testing the micro-motion life of a turbine tenon connection structure, characterized by: A device for testing the micro-motion life of a turbine tenon connection structure according to claim 3 is used; and a method for testing the micro-motion life of a turbine tenon connection structure comprises the following steps: Step 1: Install the tenon fixture (300) on the vibration exciter (200), and fix the tenon piece (700) on the tenon fixture (300); Step 2: The two half fastening sleeves (320) are mounted on the outside of the connecting tube (330) so that the corners of the tenon piece are located in the corner cutout structure of the tenon support bracket (322); Step 3: Assemble the mortise and tenon piece (500) and the tenon piece (700) together; Step 4: Adjust the position of the mortise and tenon anti-deformation fixture (600) so that the mortise and tenon piece is located between the two constraint blocks, and fix the position of the mortise and tenon anti-deformation fixture (600); Step 5: Fix the mortise and tenon piece (500) to the mortise and tenon fixing fixture (400); adjust the position of the top plate and fix it; fix the mortise and tenon fixing fixture to the top plate so that the mortise and tenon piece (500) and the tenon piece (700) remain coaxial; Step 6: Start the vibrator to make the tenon (700) move up and down slightly to simulate the actual working condition of the tenon connection structure in the turbine. According to the damage of the tenon (700) or the tenon groove (500), the life of the turbine tenon connection structure is judged.

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