Using method of tubular column vibration test device with elastic supporting mechanism

Abstract

The invention discloses a use method of a tubular column vibration test device with an elastic supporting mechanism, and belongs to the technical field of tubular column vibration test. The tubular column vibration test device comprises an inner tubular column, an outer tubular column and an elastic supporting mechanism arranged between the inner tubular column and the outer tubular column, and the use method comprises the following steps: establishing an inner tubular column finite element model by using finite element software, the supporting position of the elastic supporting mechanism and the stiffness coefficient of a spring used by the elastic supporting mechanism are determined through a numerical simulation method; the elastic supporting mechanism is assembled according to the determined stiffness coefficient of the spring used by the elastic supporting mechanism, and the elastic supporting mechanism is installed according to the determined supporting position of the elastic supporting mechanism; and after the installation of the tubular column vibration test device is completed, applying vibration to the inner tubular column to carry out a tubular column vibration test. The elastic supporting mechanism is arranged between the inner pipe column and the outer pipe column, so that the inner pipe column can be prevented from being in contact with the outer pipe column in the vibration test process due to gravity deformation and the like, and test data can be prevented from being influenced.

Description

Technical Field

[0001] The present invention relates to the technical field of pipe string vibration testing, and particularly relates to a method for using a pipe string vibration testing device with an elastic support mechanism. Background Art

[0002] The injection-production pipe string or oil well pipe string of a gas storage reservoir will be subjected to the excitation of internal fluid, resulting in pipe string vibration, which poses a severe challenge to the service life of the pipe string and the safe operation of equipment. To study the influence brought by the pipe string vibration phenomenon, currently, the pipe string vibration test is usually carried out to analyze the vibration law of the pipe string. The pipe string vibration test uses a scaled-down similar model for the test. Although the prototype oil pipe and casing have been scaled, the similar model still has a length of several meters; moreover, the inner pipe string of the simulated oil pipe usually uses a PE pipe, which has a certain flexibility. Affected by the length-diameter ratio and the shape of the pipe string, the inner pipe string of the simulated oil pipe will contact the outer pipe string of the simulated casing during vibration due to gravity, affecting the test data. Summary of the Invention

[0003] To solve the above technical problems, the present invention proposes a method for using a pipe string vibration testing device with an elastic support mechanism. By arranging an elastic support mechanism between the inner pipe string and the outer pipe string to support the inner pipe string, it is prevented that the inner pipe string contacts the outer pipe string during the vibration test due to gravity deformation, etc., affecting the test data.

[0004] The present invention specifically adopts the following technical solutions: A method for using a pipe string vibration testing device with an elastic support mechanism, the pipe string vibration testing device includes an inner pipe string, an outer pipe string, and an elastic support mechanism arranged between the inner pipe string and the outer pipe string. The elastic support mechanism includes an inner pipe string support pipe bracket and at least two arc-shaped plates arranged circumferentially along the inner pipe string support pipe bracket. The inner pipe string support pipe bracket and the arc-shaped plates are connected by springs; The method for using includes the steps: S1. Establish a finite element model of the inner pipe string using finite element software, and determine the support position of the elastic support mechanism and the stiffness coefficient of the spring used in the elastic support mechanism through numerical simulation methods; S2. Assemble the elastic support mechanism according to the stiffness coefficient of the spring used in the elastic support mechanism determined in step S1, and install the elastic support mechanism according to the support position of the elastic support mechanism determined in step S1; S3. After the pipe string vibration testing device is installed, apply vibration to the inner pipe string to conduct the pipe string vibration test.

[0005] Further, step S1 is specifically: S11. Establish a finite element model of the inner pipe string according to the structure and dimensions of the inner pipe string of the pipe string vibration test device. After applying boundary conditions, conduct a static analysis to obtain the natural deformation state of the inner pipe string under the action of gravity only. S12. According to the static analysis results in step S11, preliminarily select the pipe section with the largest deformation of the inner pipe string as the area where the elastic support mechanism needs to be applied. S13. Based on the finite element model of the inner pipe string established in step S11, add elastic support arc surface models for simulating the elastic support mechanism in the area where the elastic support mechanism is preliminarily selected in step S12 and its two side areas. Control the elastic support force of the elastic support arc surface model with the basic stiffness. Use the orthogonal test method to adjust the number, position and basic stiffness of the elastic support arc surface models to conduct a static analysis, and analyze the deformation nephogram of the inner pipe string under different support conditions. S14. Compare the deformation nephograms of the inner pipe string under different support conditions obtained in step S13, and select the range of the number, position and basic stiffness of the elastic support arc surface models that can meet the deformation requirement of the inner pipe string. S15. Conduct a modal analysis on the inner pipe string model without support and the inner pipe string model with the support conditions selected in step S14, obtain the change of the first n natural frequencies of the inner pipe string before and after applying the support, analyze and judge the influence degree of applying the support on the natural frequency of the inner pipe string, and select the range of the number, position and basic stiffness of the elastic support arc surface models that can meet the requirement of the change of the natural frequency. S16. Determine the stiffness coefficient of the spring used in the actual elastic support mechanism according to the range of the basic stiffness of the elastic support arc surface model determined in step S15.

[0006] Further, the deformation requirement of the inner pipe string in step S14 is that the deformation of the inner pipe string after applying the support is within 20% of the radius difference between the inner and outer pipe strings.

[0007] Further, the requirement for the change of the natural frequency of the inner pipe string in step S15 is that the difference between the natural frequency of each order of the inner pipe string after applying the support and the corresponding order natural frequency of the inner pipe string before applying the support is within 3 Hz.

[0008] Further, the stiffness coefficient of the spring used in the actual elastic support mechanism in step S16 is calculated by the following formula: K = E×S; In the formula, K is the stiffness coefficient of the spring, E is the basic stiffness, and S is the area of the elastic support arc surface model.

[0009] Further, the inner pipe string support pipe shoe is arranged outside the inner pipe string and fits with the outer wall of the inner pipe string, and the outer wall of the arc plate fits with the inner wall of the outer pipe string.

[0010] Furthermore, the inner pipe column support pipe shoe is a circular pipe shoe or a semi-circular pipe shoe.

[0011] Furthermore, the inner pipe column is a soft plastic pipe, and the outer pipe column is a hard plastic pipe and is spliced by several sections of hard plastic pipes.

[0012] Furthermore, the inner pipe column and the outer pipe column include a vertical well section located in the upper part, a horizontal section located in the lower part, and an inclined section between the vertical well section and the horizontal section, and there are curved build-up sections between the vertical well section and the inclined section, and between the horizontal section and the inclined section; The end of the vertical well section and the end of the horizontal section of the inner pipe column are fixed to the outer pipe column through fixed collar rings, and the inclined section of the inner pipe column is supported by at least one elastic support mechanism.

[0013] Furthermore, the pipe column vibration test device further includes a test fixing frame adapted to the installation shape of the outer pipe column and an air compressor for applying vibration to the inner pipe column; A number of outer pipe column support pipe shoes are provided on the test fixing frame, the outer pipe column is sleeved in the outer pipe column support pipe shoe, and a gasket is provided between the outer pipe column and the outer pipe column support pipe shoe; The air outlet of the air compressor is hermetically connected to one end of the inner pipe column.

[0014] The present invention has the following beneficial effects: (1) The present invention provides a use method of a pipe column vibration test device with an elastic support mechanism. By arranging an elastic support mechanism between the inner pipe column and the outer pipe column to support the inner pipe column, the elastic force of the elastic support mechanism can maintain the inner pipe column at the center of the outer pipe column and keep the inner pipe column relatively stable during the vibration test, preventing the inner pipe column from contacting the outer pipe column during the vibration test due to gravity deformation or the like and affecting the test data. At the same time, the elastic force of the elastic support mechanism is relatively small and will not affect the vibration of the inner pipe column; (2) The elastic support mechanism provided by the present invention has a simple structure and is easy to install, and is convenient to adjust the support position according to actual needs. Description of the Drawings

[0015] Figure 1 It is a schematic diagram of the overall structure of the pipe column vibration test device; Figure 2 It is a schematic diagram of the structure of the outer pipe column support pipe shoe; Figure 3 It is a schematic diagram of the structure of the elastic support mechanism with the inner pipe column support pipe shoe being a circular pipe shoe; Figure 4 It is a schematic diagram of the structure of the elastic support mechanism with the inner pipe column support pipe shoe being a semi-circular pipe shoe; Figure 5 For Figure 3Schematic structural diagram of the elastic support mechanism installed between the inner pipe column and the outer pipe column; Figure 6 is Figure 4 Schematic structural diagram of the elastic support mechanism installed between the inner pipe column and the outer pipe column; Figure 7 is the deformation nephogram of the inner pipe column under the condition of no support; Figure 8 is the schematic diagram of applying elastic support at different positions of the straight inclined section of the inner pipe column; Figure 9 is for applying a basic stiffness of 0.001 N / mm 3 deformation nephogram of the inner pipe column after the support is applied; Figure 10 is for applying a basic stiffness of 0.0015 N / mm 3 deformation nephogram of the inner pipe column after the support is applied.

[0016] In the figure, the markings are as follows: 1. Inner pipe column; 2. Outer pipe column; 3. Elastic support mechanism; 301. Inner pipe column support pipe bracket; 302. Arc-shaped plate; 303. Spring; 4. Test fixing frame; 5. Outer pipe column support pipe bracket; 501. Upper support pipe bracket of the outer pipe column; 502. Lower support pipe bracket of the outer pipe column. Specific implementation manner

[0017] The following further describes the specific implementation manner of the present invention in conjunction with the accompanying drawings and specific embodiments.

[0018] Referring to Figure 1 , this embodiment provides a pipe column vibration test device with an elastic support mechanism, including an inner pipe column 1, an outer pipe column 2 sleeved outside the inner pipe column 1, an elastic support mechanism 3 arranged between the inner pipe column 1 and the outer pipe column 2, and a test fixing frame 4 adapted to the installation shape of the outer pipe column 2. At least one of the above elastic support mechanisms 3 is provided and used to support the inner pipe column, and a plurality of outer pipe column support pipe brackets 5 are arranged on the above test fixing frame 4 and used to fix the outer pipe column. Specifically, the above inner pipe column 1 is a soft plastic pipe, and specifically, a PE pipe can be used; the above outer pipe column 2 is a hard plastic pipe, and specifically, a transparent acrylic pipe can be used. The outer pipe column 2 is composed of several sections of hard plastic pipes spliced together, and adjacent two hard plastic pipes are connected through flanges at the pipe ends; the pipeline forms of the above inner pipe column 1 and outer pipe column 2 include a vertical well section at the upper part, a horizontal section at the lower part, and a straight inclined section between the vertical well section and the horizontal section, and there are curved build-up sections between the vertical well section and the straight inclined section, and between the horizontal section and the straight inclined section; the ends of the vertical well section and the horizontal section of the above inner pipe column 1 are fixed to the outer pipe column 2 through fixed collar rings, and the straight inclined section of the inner pipe column 1 is supported by at least one elastic support mechanism 3 to prevent the inner pipe column 1 made of soft plastic from deforming due to gravity or contacting the outer pipe column 2 during vibration.

[0019] Reference Figure 2 , the above-mentioned outer pipe column support pipe bracket 5 specifically includes an upper support pipe bracket 501 for the outer pipe column and a lower support pipe bracket 502 for the outer pipe column. The upper support pipe bracket 501 for the outer pipe column and the lower support pipe bracket 502 for the outer pipe column are connected by bolts on both sides of the pipe bracket. The lower support pipe bracket 502 for the outer pipe column is fixedly connected to the test fixing frame 4. By sleeving the outer pipe column 2 inside the outer pipe column support pipe bracket 5, the outer pipe column is fixed to the test fixing frame 4, and a gasket is provided between the outer pipe column 2 and the outer pipe column support pipe bracket 5.

[0020] Reference Figure 3 and Figure 4 , the above-mentioned elastic support mechanism 3 specifically includes an inner pipe column support pipe bracket 301 and at least two arc-shaped plates 302 arranged circumferentially along the inner pipe column support pipe bracket 301, and the inner pipe column support pipe bracket 301 and the arc-shaped plates 302 are connected by springs 303. The above-mentioned inner pipe column support pipe bracket 301 is specifically a circular pipe bracket or a semi-circular pipe bracket. When the inner pipe column support pipe bracket 301 is a circular pipe bracket, three arc-shaped plates 302 are provided, and two of the arc-shaped plates 302 are symmetrically arranged on the left and right sides of the inner pipe column support pipe bracket 301 respectively, and the other arc-shaped plate 302 is arranged directly below the inner pipe column support pipe bracket 301; when the inner pipe column support pipe bracket 301 is a semi-circular pipe bracket, two arc-shaped plates 302 are provided, and the two arc-shaped plates 302 are symmetrically arranged at the lower left and lower right of the inner pipe column support pipe bracket 301 respectively. In addition, the inner diameter of the above-mentioned inner pipe column support pipe bracket 301 matches the outer diameter of the inner pipe column 1 to ensure that the two are in contact and at the same time the inner pipe column support pipe bracket can move along the inner pipe column when a thrust is applied.

[0021] Reference Figure 5 and Figure 6 , the above-mentioned elastic support mechanism 3 is installed between the inner pipe column 1 and the outer pipe column 2, and the inner wall of the inner pipe column support pipe bracket 301 is in contact with the outer wall of the inner pipe column 1, and the outer wall of the arc-shaped plate 302 is in contact with the inner wall of the outer pipe column 2. Through this elastic support mechanism, the support of the inner pipe column can be realized.

[0022] In addition, for the convenience of installing and fixing the springs of the above-mentioned elastic support mechanism, installation holes for installing and fixing the springs are provided on the outer wall of the inner pipe column support pipe bracket 301 and the inner wall of the arc-shaped plate 302. One end of the spring is fixed in the installation hole on the outer wall of the inner pipe column support pipe bracket, and the other end is fixed in the installation hole on the inner wall of the arc-shaped plate.

[0023] In addition, the tubing vibration test device of this embodiment further includes an air compressor (not shown in the figure) for applying vibration to the inner tubing 1. The air outlet of the air compressor is hermetically connected to one end of the inner tubing 1. Additionally, along the length direction of the inner tubing 1, several vibration sensors (not shown in the figure) for monitoring the vibration of the inner tubing 1 are arranged. Compressed air is applied into the inner tubing 1 to simulate tubing vibration, and the vibration data of different regions of the inner tubing is monitored through the vibration sensors.

[0024] In the application process of the above elastic support mechanism, it is not directly applied. Instead, it is necessary to first determine its support position, quantity, and the spring stiffness coefficient to ensure that the elastic support mechanism supports the inner tubing while minimizing the impact on the vibration of the inner tubing. Therefore, in this embodiment, a finite element model of the inner tubing is first established using finite element software, and the support position of the elastic support mechanism and the spring stiffness coefficient of the spring used in the elastic support mechanism are determined through numerical simulation methods. The specific steps are as follows: S11. Establish a finite element model of the inner tubing according to the structure and dimensions of the inner tubing used in the tubing vibration test device, apply boundary conditions, and then perform a static analysis to obtain the natural deformation state of the inner tubing under the action of gravity only. S12. According to the static analysis results of step S11, preliminarily select the tubing section with the largest deformation of the inner tubing as the area where the elastic support mechanism needs to be applied. S13. Based on the finite element model of the inner tubing established in step S11, add an elastic support arc surface model for simulating the elastic support mechanism in the area where the elastic support mechanism is preliminarily selected in step S12 and the extended areas on both sides, and control the elastic support force of the elastic support arc surface with the basic stiffness. Use the orthogonal test method to adjust the number, position, and basic stiffness of the elastic support arc surface models for static analysis, and analyze the deformation nephogram of the inner tubing under different support conditions. S14. Compare the deformation nephograms of the inner tubing under different support conditions obtained in step S13, and select the support conditions that can meet the requirements of the inner tubing deformation amount, that is, the range of the number of elastic support arc surface models, the range of positions, and the range of basic stiffness. Specifically, the requirement for the inner tubing deformation amount is that the deformation amount of the inner tubing after applying the support is within 20% of the radius difference between the inner and outer tubings. S15. Perform a modal analysis on the inner tubing model without support and the inner tubing model with the support conditions selected in step S14, obtain the change in the first n natural frequencies of the inner tubing before and after applying the support, analyze and judge the influence degree of applying the support on the natural frequency of the inner tubing, and select the support conditions that can meet the requirements of the natural frequency change. Specifically, the requirement for the change in the natural frequency of the inner tubing is that the difference between the natural frequency of each order of the inner tubing after applying the support and the corresponding order natural frequency of the inner tubing before applying the support is within 3 Hz. The support conditions screened through this step can simultaneously meet the requirements of the inner tubing deformation amount and the change in the natural frequency. S16. Determine the stiffness coefficient of the spring used in the actual elastic support mechanism according to the basic stiffness range of the elastic support arc surface model determined in step S15; and the stiffness coefficient of the spring used in the actual elastic support mechanism is calculated by the following formula: K = E × S; In the formula, K is the stiffness coefficient of the spring, E is the basic stiffness, and S is the area of the elastic support arc surface model.

[0025] Based on the above steps, determine the support position, quantity, and the stiffness coefficient of the spring of the elastic support mechanism in the pipe string vibration test device of this embodiment. In this embodiment, the Figure 4 shown elastic support mechanism is adopted, and the outer diameter of the inner pipe string is 20 mm, the inner diameter of the outer pipe string is 60 mm, and the total length is 5250 mm.

[0026] In this embodiment, first establish a finite element model of the inner pipe string according to the structure and dimensions of the inner pipe string of the pipe string vibration test device, apply boundary conditions and then perform static analysis to obtain the natural deformation state of the inner pipe string under the action of only gravity, as Figure 7 shown; according to Figure 7 the static analysis results, it can be obtained that the pipe section with the largest deformation of the inner pipe string is mainly concentrated in the stabilized inclination section, and the middle part of the stabilized inclination section has the largest deformation, with the maximum deformation being 15.75 mm. The middle part of the stabilized inclination section with the largest deformation of the inner pipe string is pre-selected as the area where the elastic support mechanism needs to be applied.

[0027] On the basis of determining that the area with the largest deformation of the inner pipe string in the natural deformation state is the middle part of the stabilized inclination section, expand the selected range of the support position, that is, add elastic support arc surface models (contact area is 100 mm 2 ) for simulating the elastic support mechanism in the area where the elastic support mechanism is applied and the extended areas of the stabilized inclination sections on both sides in the pre-selected middle part area of the stabilized inclination section, as Figure 8 shown as the schematic diagram of applying elastic support at different positions of the stabilized inclination section of the inner pipe string. Specifically, the elastic support arc surface model can be applied at one or two or more positions from position a to position i, and on this basis, adjust the basic stiffness of the elastic support arc surface model to obtain different combinations of support conditions, and perform static analysis on different support conditions to obtain the deformation nephogram of the inner pipe string under different support conditions, and select the range of the number, position, and basic stiffness of the elastic support arc surface models that can make the deformation of the inner pipe string within 20% of the radius difference between the inner and outer pipe strings (that is, the deformation is within 4 mm); among them, apply the elastic support arc surface model at the middle position (i.e., position e) of the stabilized inclination section of the inner pipe string, and set the initial basic stiffness to 0.001 N / mm 3 , and after performing static analysis, obtain as Figure 9The deformed contour map of the inner pipe string is shown. Under this support condition, the maximum deformation of the overall inner pipe string is 4.54 mm. After applying the support, the overall deformation of the inner pipe string decreases significantly, but the deformation is still large and does not meet the requirement of the inner pipe string deformation. At this position, the foundation stiffness is further adjusted to 0.0015 N / mm 3 and a static analysis is carried out to obtain as Figure 10 the deformed contour map of the inner pipe string shown. Under this support condition, the maximum deformation of the overall inner pipe string is 3.86 mm, which meets the requirement. In addition, when setting the foundation stiffness, the selection range of the foundation stiffness can also be obtained by using the stiffness coefficient parameters of common stainless steel springs. If the outer diameter and the number of active coils of the spring for this support are fixed at 10 mm and 4 turns respectively, its stiffness coefficient is controlled by the wire diameter. The range of the spring stiffness coefficient under this condition is shown in Table 1 below. This table only illustrates the stiffness coefficients of springs with different wire diameters under fixed outer diameter and number of turns, so as to determine the selection range of the foundation stiffness. The range of the foundation stiffness can also be determined by adjusting the outer diameter and the number of turns

[0028] Table 1 Foundation stiffness corresponding to the stiffness coefficients of different springs

[0029] After applying the elastic support, the natural frequency of the inner pipe string will change. Therefore, continue to perform modal analysis on the inner pipe string model without support and the inner pipe string models with different support conditions to obtain the change of the first ten natural frequencies of the inner pipe string before and after applying the support. Among them, the first ten natural frequencies of the model without support and the model with an elastic support arc surface applied at the middle position of the stable inclination section of the inner pipe string (i.e., position e), and the foundation stiffness is set to 0.0015 N / mm 3 are shown in Table 2. The difference between the natural frequency of each order of the inner pipe string after applying this support and the corresponding natural frequency of the inner pipe string before applying the support is within 3 Hz, indicating that the influence of applying the support on the natural frequency of the inner pipe string is acceptable

[0030] Table 2 The first ten natural frequencies before and after applying the support

[0031] In addition, to a certain extent, the natural frequency can also reflect the forced vibration characteristics of the inner pipe string. When the change in the natural frequency after applying the support is small (within 3 Hz), it indicates that the applied elastic support basically does not affect the forced vibration of the inner pipe string. This is because the foundation stiffness of the applied elastic support is small, and the elastic force it can provide is relatively small, so it basically does not affect the vibration of the inner pipe string

[0032] Finally, use the foundation stiffness of 0.0015 N / mm of the above elastic support arc surface model 3The stiffness coefficient of the spring used in the actual elastic support mechanism is determined as K = E×S = 0.15 N / mm. On the basis of determining the stiffness coefficient of the spring, the spring specifications can also be determined by using the following formula or through Table 1: ; In the formula, G is the rigidity modulus of the spring wire, d is the wire diameter of the spring, N C is the number of active coils, D m is the mean diameter.

[0033] According to the stiffness coefficients of common stainless steels in Table 1, the spring of the elastic support mechanism is selected as a stainless steel spring, with its rigidity modulus G = 7200, wire diameter of the spring being 0.5 mm, total number of coils being 6, number of active coils being 4, outer diameter being 10 mm, and length being 15 mm (the spring length is determined according to the annulus distance between the inner and outer pipe columns. There is a 20-mm annulus between the inner and outer pipe columns. After removing the thicknesses of the pipe support and the arc-shaped plate, the spring length is finally determined to be 15 mm). The stiffness coefficient of this spring is 0.16 N / mm, which is basically the same as 0.15 N / mm.

[0034] On the basis of determining the support position, quantity, and stiffness coefficient of the spring by using the simulation method described above, first assemble the elastic support mechanism according to the stiffness coefficient of the spring used in the determined elastic support mechanism, and then sleeve the elastic support mechanism on the inner pipe column according to the determined support position of the elastic support mechanism. Since the outer diameter of the inner pipe column support pipe support on the elastic support mechanism matches the inner diameter of the inner pipe column, the two are firmly combined after installation and will not move under the action of a relatively large external force. At the same time, fix the vibration sensor on the outer wall of the inner pipe column; after installing the elastic support mechanism and the vibration sensor, install the outer pipe column. When installing the outer pipe column, first sleeve multiple acrylic pipes on the outer of the inner pipe column, and then fix the multiple acrylic pipes into one body through flanges and bolts; finally, fix the installed inner pipe column and outer pipe column on the test fixture through the outer pipe column support pipe support. After checking that the installation is correct, use an air compressor to apply vibration to the inner pipe column for the pipe column vibration test. At the same time, the vibration sensor monitors the vibration data of the inner pipe column.

[0035] During the above-mentioned pipe column vibration test, there was no contact between the inner pipe column and the outer pipe column, which improved the accuracy of the vibration data monitored by the vibration sensor.

[0036] In addition, in the actual oil and gas well exploitation, an annulus protection fluid is injected between the tubing and the casing, and the annulus protection fluid will form an annulus pressure between the tubing and the casing. In this embodiment, on the basis of applying support to the inner pipe column due to gravity deformation, the basic stiffness of the elastic support mechanism can be adjusted according to the annulus pressure, so as to simulate the action of the annulus protection fluid between the actual tubing and the casing, and more realistically simulate the actual working conditions.

[0037] It should be noted that the parts not described in the present invention can be realized by adopting or referring to the existing technologies.

[0038] Certainly, the above description is not a limitation to the present invention, and the present invention is not limited to the above examples. Any changes, modifications, additions or substitutions made by those skilled in the art within the scope of the essence of the present invention should also fall within the protection scope of the present invention.

Claims

1. A method for using a pipe column vibration test device having an elastic support mechanism, characterized in that: The pipe column vibration test device comprises an inner pipe column, an outer pipe column and an elastic support mechanism arranged between the inner pipe column and the outer pipe column, wherein the elastic support mechanism comprises an inner pipe column support pipe bracket and at least two arc-shaped plates arranged along the circumference of the inner pipe column support pipe bracket, and the inner pipe column support pipe bracket and the arc-shaped plates are connected by a spring; The method of use comprises the steps of: S1. Establish a finite element model of the inner pipe column using finite element software, and determine the support position of the elastic support mechanism and the stiffness coefficient of the spring used in the elastic support mechanism by numerical simulation method; S2, assembling the elastic support mechanism according to the stiffness coefficient of the spring used by the elastic support mechanism determined in step S1 and installing the elastic support mechanism according to the supporting position of the elastic support mechanism determined in step S1; S3. After the tubing string vibration test device is installed, vibration is applied to the inner tubing string to perform a tubing string vibration test.

2. The method for using the pipe column vibration test device with an elastic support mechanism according to claim 1, characterized in that: The step S1 is specifically as follows: S11. Establish a finite element model of the inner pipe string according to the structure and size of the inner pipe string for the pipe string vibration test device, perform static analysis after applying boundary conditions, and obtain the natural deformation state of the inner pipe string under the action of gravity only; S12, according to the static analysis result of step S11, pre-selecting the pipe section with the largest deformation of the inner pipe string as the area where the elastic support mechanism needs to be applied; S13, based on the finite element model of the inner pipe column established in step S11, an elastic support arc surface model for simulating the elastic support mechanism is added to the elastic support mechanism application area and the areas on both sides thereof pre-selected in step S12, and the elastic support force of the elastic support arc surface model is controlled by the basic stiffness, and the number, position and basic stiffness of the elastic support arc surface model are adjusted by the orthogonal test method to perform static analysis, and analyze the deformation cloud diagram of the inner pipe column under different support conditions; S14, comparing the deformation cloud diagrams of the inner pipe column under different support conditions obtained in step S13, and selecting the number range, position range and foundation stiffness range of the elastic support arc surface model that can meet the deformation requirements of the inner pipe column; S15, performing modal analysis on the inner pipe string model without support and the inner pipe string model with the support condition selected in step S14, obtaining the first n-order natural frequency changes of the inner pipe string before and after the support is applied, analyzing and judging the influence of the support on the natural frequency of the inner pipe string, and selecting the number range, position range and foundation stiffness range of the elastic support arc surface model that can meet the requirements of the natural frequency change; S16. Determine the stiffness coefficient of the spring used in the actual elastic support mechanism according to the basic stiffness range of the elastic support arc surface model determined in step S15.

3. The method for using the pipe column vibration test device with an elastic support mechanism according to claim 2, characterized in that: The deformation requirement of the inner pipe string in step S14 is: the deformation of the inner pipe string after the support is applied is within 20% of the difference between the radius of the inner and outer pipe strings.

4. The method for using the pipe column vibration test device with an elastic support mechanism according to claim 2, characterized in that: The requirement for the change of the natural frequency of the inner pipe string in step S15 is that the difference between the natural frequency of each order of the inner pipe string after the support is applied and the natural frequency of the corresponding order of the inner pipe string before the support is applied is within 3 Hz.

5. The method for using the pipe column vibration test device with an elastic support mechanism according to claim 2, characterized in that: The spring coefficient of the actual elastic support mechanism in step S16 is calculated by the following formula: K = E × S; Where K is the spring stiffness coefficient, E is the basic stiffness, and S is the area of ​​the elastic support arc surface model.

6. The method for using the pipe column vibration test device with an elastic support mechanism according to claim 1, characterized in that: The inner pipe column support bracket is arranged outside the inner pipe column and fits with the outer wall of the inner pipe column, and the outer wall of the arc plate fits with the inner wall of the outer pipe column.

7. The method for using the pipe column vibration test device with an elastic support mechanism according to claim 1, characterized in that: The inner pipe column support tube bracket is a circular tube bracket or a semicircular tube bracket.

8. The method for using the pipe column vibration test device with an elastic support mechanism according to claim 1, characterized in that: The inner pipe column is a soft plastic pipe, and the outer pipe column is a hard plastic pipe and is formed by splicing a plurality of sections of hard plastic pipes.

9. The method for using the pipe column vibration test device with an elastic support mechanism according to claim 1, characterized in that: The inner pipe string and the outer pipe string include a vertical well section at the top, a horizontal section at the bottom, and a stabilizing section between the vertical well section and the horizontal section, and a curved deflection section between the vertical well section and the stabilizing section and between the horizontal section and the stabilizing section; The ends of the vertical well section and the horizontal section of the inner pipe string are fixed to the outer pipe string through fixed collars, and the inclination stabilizing section of the inner pipe string is supported by at least one elastic supporting mechanism.

10. The method for using the pipe column vibration test device with an elastic support mechanism according to claim 1, characterized in that: The pipe string vibration test device also includes a test fixture adapted to the installation shape of the outer pipe string and an air compressor for applying vibration to the inner pipe string; The test fixture is provided with a plurality of outer pipe column support brackets, the outer pipe column is sleeved in the outer pipe column support brackets, and a gasket is provided between the outer pipe column and the outer pipe column support brackets; The air outlet of the air compressor is sealed and connected to one end of the inner pipe column.

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