Threaded sealing surface contact stress measuring device and measuring method

Abstract

The invention provides a thread sealing surface contact stress measuring device and method, and the device comprises a clamp which is used for clamping a test sample; the sealing surface test probe is fixed to the outer wall of the coupling at the sealing surface of the test sample; the shoulder test probe is fixed to the outer wall of the coupling at the shoulder of the test sample; the external thread rotation sensor is used for controlling the rotation angles of the sealing surface test structure and the shoulder test structure relative to the external thread; the internal thread rotation sensor is used for controlling the rotation angles of the sealing surface test structure and the shoulder test structure relative to the internal thread; the output end of the sound wave signal generation device is connected with the external thread rotation sensor and the internal thread rotation sensor; and the data acquisition structure is used for receiving signals fed back by the sealing surface test structure and the shoulder test structure. According to the technical scheme, the problem that the contact stress of a special thread in the prior art can only be subjected to model analysis and cannot be actually tested is effectively solved.

Description

Technical Field

[0001] The present invention relates to the technical field of special threads, and more particularly, to a device and a method for measuring the contact stress of a thread sealing surface. Background Art

[0002] With the continuous deepening of natural gas exploration and development, the proportion of deep wells (well depth > 3000 m) and ultra-deep wells (well depth > 6000 m) in gas field development is increasing continuously. The downhole working environment of deep wells and ultra-deep wells is complex, facing the "three highs" situation of high temperature (bottom hole temperature up to 180 °C), high pressure (downhole pressure > 80 MPa) and highly corrosive media. Traditional API oil casing pipes can no longer meet the downhole working conditions, and non-API special thread oil casing pipe joints with high gas tightness are increasingly widely used in the exploitation of high-temperature and high-pressure gas wells. Compared with traditional API threads, the special thread joints of oil casing pipes add a metal-to-metal sealing structure in their structure, and control the pressure of internal fluid through the contact stress generated after the inner and outer thread sealing surfaces come into contact after making up the connection. Generally, it is considered that the condition for preventing the leakage of fluid in the pipe is that the average contact stress on the metal sealing surface is greater than the pressure of the fluid to be sealed in the pipe.

[0003] At present, the research on the contact stress of special thread sealing surfaces at home and abroad is mainly limited to theoretical model research, and at the same time, finite element analysis software is used to simulate and calculate the magnitude and distribution of contact stress. Summary of the Invention

[0004] The main object of the present invention is to provide a device and a method for measuring the contact stress of a thread sealing surface, so as to solve the problem in the related art that the contact stress of special threads can only be analyzed by models and cannot be actually tested.

[0005] To achieve the above object, according to one aspect of the present invention, there is provided a device for measuring the contact stress of a thread sealing surface, including: a fixture for clamping a test sample; a sealing surface test structure including a sealing surface test probe, the sealing surface test probe being fixed to the outer wall of the coupling at the sealing surface of the test sample and used for testing the contact stress at the sealing surface of the test sample; a shoulder test structure including a shoulder test probe, the shoulder test probe being fixed to the outer wall of the coupling at the shoulder of the test sample and used for testing the contact stress at the shoulder of the test sample; an external thread rotation sensor for controlling the rotation angle of the sealing surface test structure and the shoulder test structure relative to the external thread; an internal thread rotation sensor for controlling the rotation angle of the sealing surface test structure and the shoulder test structure relative to the internal thread; an acoustic signal generating device, the output end of the acoustic signal generating device being connected to the external thread rotation sensor and the internal thread rotation sensor; and a data acquisition structure for receiving the signals fed back by the sealing surface test structure and the shoulder test structure.

[0006] Further, the thread seal surface contact stress measuring device further includes a container and a connecting pipe. The inside of the container contains a coupling agent. The first end of the connecting pipe communicates with the container, and the second end of the connecting pipe faces the test sample.

[0007] Further, the thread seal surface contact stress measuring device further includes a power supply, which is connected to the connecting pipe and used to charge the coupling agent.

[0008] Further, the data acquisition structure includes a flaw detector and a processor. The flaw detector receives the signal of the data acquisition structure, and the processor is connected to the flaw detector and used to process the measurement signal of the flaw detector.

[0009] Further, the acoustic wave signal generating device includes an analog signal generator and an analog signal display.

[0010] Further, the thread seal surface contact stress measuring device further includes a pump body, which is arranged at the first end of the connecting pipe.

[0011] Further, a filling valve is arranged on the container, and a transmission valve is arranged on the connecting pipe.

[0012] According to another aspect of the present invention, a method for measuring the thread seal surface contact stress is provided. The thread seal surface contact stress measuring device described in the above items is used for measurement. The method for measuring the thread seal surface contact stress includes: starting the pump body to spray the coupling agent through the connecting pipe towards the test sample; fixing the seal surface test structure and the shoulder test structure; adjusting the measurement angles of the seal surface test structure and the shoulder test structure through the external thread rotation sensor and the internal thread rotation sensor to obtain a measurement signal; transmitting the measurement signal to the data acquisition structure to obtain stress data.

[0013] Further, the step of fixing the seal surface test structure and the shoulder test structure includes: clamping the seal surface test structure and the shoulder test structure on the test sample through a fixture; the seal surface test structure and the shoulder test structure are in contact with the test sample; sliding axially along the test sample to adjust the positions of the seal surface test structure and the shoulder test structure and fixing them.

[0014] Further, the step of starting the pump body to spray the coupling agent through the connecting pipe towards the test sample includes: starting the pump body and spraying the coupling agent towards the test sample; closing the pump body when the outer surface of the test sample is completely sprayed.

[0015] Applying the technical solution of the present invention, the test sample is clamped by a fixture. The sealing surface test structure is used to test the contact stress at the sealing surface of the test sample, and the shoulder test structure is used to test the contact stress at the shoulder of the test sample. The external thread rotation sensor and the internal thread rotation sensor respectively control the rotation angles of the sealing surface test structure and the shoulder test structure. The output end of the acoustic wave signal generating device is connected to the external thread rotation sensor and the internal thread rotation sensor, and the data acquisition structure is used to receive the signals fed back by the external thread rotation sensor and the internal thread rotation sensor. Through the above settings, the sealing surface test structure includes a sealing surface test probe, which can test the contact stress at the sealing surface of the test sample. The shoulder test structure includes a shoulder test probe, which can test the test stress at the shoulder of the test sample. The external thread rotation sensor can adjust the rotation angles of the sealing surface test structure and the shoulder test structure relative to the external thread, and the internal thread rotation sensor can adjust the rotation angles of the sealing surface test structure and the shoulder test structure relative to the internal thread. The acoustic wave signal generating device emits a signal and transmits it to the test sample. The acoustic wave is received by the sealing surface test structure and the shoulder test structure and then transmitted to the data acquisition structure. The data acquisition structure then receives the fed-back signal and processes the fed-back signal to obtain specific contact stress data. Therefore, the technical solution of the present application effectively solves the problem in the related art that the contact stress of special threads can only be analyzed by models and cannot be actually tested. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The accompanying drawings forming a part of this application are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0017] Figure 1 shows a schematic structural diagram of an embodiment of a threaded sealing surface contact stress measuring device according to the present invention;

[0018] Figure 2 shows a schematic flow diagram of an embodiment of a threaded sealing surface contact stress measuring method according to the present invention;

[0019] Figure 3 shows Figure 2 a specific flow diagram of step S20 of the threaded sealing surface contact stress measuring method;

[0020] Figure 4 shows Figure 2 a specific flow diagram of step S10 of the threaded sealing surface contact stress measuring method.

[0021] Among them, the above-mentioned drawings include the following reference numerals:

[0022] 1. Test sample; 10. Fixture; 20. Sealing surface test structure; 30. Shoulder test structure; 40. External thread rotation sensor; 50. Internal thread rotation sensor; 60. Acoustic signal generating device; 61. Analog signal generator; 62. Analog signal display; 70. Data acquisition structure; 71. Flaw detector; 72. Processor; 81. Container; 811. Filling valve; 82. Connecting pipe; 821. Transmission valve; 83. Power supply; 84. Pump body. Detailed implementation mode

[0023] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and in no way limits the present invention and its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0024] It should be noted that the terms used here are only for describing the specific implementation mode and are not intended to limit the exemplary embodiments according to the present application. As used here, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or their combinations.

[0025] Unless otherwise specifically stated, the relative arrangements, numerical expressions and values of the components and steps described in these embodiments do not limit the scope of the present invention. At the same time, it should be understood that for the sake of description, the dimensions of the various parts shown in the drawings are not drawn in actual proportional relationship. Technologies, methods and devices known to those of ordinary skill in the relevant field may not be discussed in detail, but where appropriate, the technologies, methods and devices should be regarded as part of the authorized specification. In all the examples shown and discussed here, any specific value should be interpreted as merely exemplary and not as a limitation. Therefore, other examples of the exemplary embodiments may have different values. It should be noted that similar reference numerals and letters indicate similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further discussed in the subsequent drawings.

[0026] As Figure 1As shown, in this embodiment, the threaded seal surface contact stress measurement device includes: a fixture 10, a seal surface test structure 20, a shoulder test structure 30, an external thread rotation sensor 40, an internal thread rotation sensor 50, an acoustic signal generating device 60, and a data acquisition structure 70. The fixture 10 is used to clamp the test sample 1. The seal surface test structure 20 includes a seal surface test probe, which is fixed to the outer wall of the collar at the seal surface of the test sample 1 and is used to measure the contact stress at the seal surface of the test sample 1. The shoulder test structure 30 includes a shoulder test probe, which is fixed to the outer wall of the collar at the shoulder of the test sample 1 and is used to measure the contact stress at the shoulder of the test sample 1. The external thread rotation sensor 40 is used to control the rotation angle of the seal surface test structure 20 and the shoulder test structure 30 relative to the external thread. The internal thread rotation sensor 50 is used to control the rotation angle of the seal surface test structure 20 and the shoulder test structure 30 relative to the internal thread. The acoustic signal generating device 60, the output end of the acoustic signal generating device is connected to the external thread rotation sensor 40 and the internal thread rotation sensor 50. The data acquisition structure 70 is used to receive the signals fed back by the seal surface test structure 20 and the shoulder test structure 30.

[0027] Applying the technical solution of this embodiment, the test sample 1 is clamped by the fixture 10. The seal surface test structure 20 is used to measure the contact stress at the seal surface of the test sample 1, and the shoulder test structure 30 is used to measure the contact stress at the shoulder of the test sample 1. The external thread rotation sensor 40 and the internal thread rotation sensor 50 respectively control the rotation angles of the seal surface test structure 20 and the shoulder test structure 30. The output end of the acoustic signal generating device 60 is connected to the external thread rotation sensor 40 and the internal thread rotation sensor 50. The data acquisition structure 70 is used to receive the signals fed back by the external thread rotation sensor 40 and the internal thread rotation sensor 50. Through the above settings, the seal surface test structure 20 includes a seal surface test probe, which can measure the contact stress at the seal surface of the test sample 1. The shoulder test structure 30 includes a shoulder test probe, which can measure the test stress at the shoulder of the test sample 1. The external thread rotation sensor 40 can adjust the rotation angle of the seal surface test structure 20 and the shoulder test structure 30 relative to the external thread. The internal thread rotation sensor 50 can adjust the rotation angle of the seal surface test structure 20 and the shoulder test structure 30 relative to the internal thread. The acoustic signal generating device 60 emits signals to the test sample. The signals are received by the seal surface test structure 20 and the shoulder test structure 30 and then transmitted to the data acquisition structure. The data acquisition structure 70 receives the fed-back signals and processes the fed-back signals to obtain specific contact stress data. Therefore, the technical solution of this embodiment effectively solves the problem that the contact stress of special threads in the related art can only be analyzed by models and cannot be actually measured.

[0028] Specifically, the process of acoustic wave transmission during the test of the thread sealing surface contact stress measuring device in this embodiment is as follows:

[0029] Before the thread is tightened, thread grease is applied to the surface, which mainly plays a lubricating role. At the same time, the thread grease can also serve as a medium for acoustic wave conduction. The ultrasonic wave of the acoustic wave signal generating device 60 acts on the surface of the sealing surface, changing its propagation direction or characteristics, and the changed ultrasonic wave is received by the data acquisition structure 70.

[0030] As Figure 1 shown, in this embodiment, the thread sealing surface contact stress measuring device further includes a container 81 and a connecting pipe 82. The inside of the container 81 contains a coupling agent. The first end of the connecting pipe 82 is communicated with the container 81, and the second end of the connecting pipe 82 faces the test sample 1. The container 81 can hold the coupling agent, and the coupling agent can improve the effect of acoustic wave conduction, thereby making the detection effect more accurate.

[0031] As Figure 1 shown, in this embodiment, the thread sealing surface contact stress measuring device further includes a power supply 83. The power supply 83 is connected to the connecting pipe 82 and is used to charge the coupling agent. The setting of the power supply 83 can further improve the conduction effect.

[0032] As Figure 1 shown, in this embodiment, the data acquisition structure 70 includes a flaw detector 71 and a processor 72. The flaw detector 71 receives the signal of the data acquisition structure 70, and the processor 72 is connected to the flaw detector 71 and is used to process the measurement signal of the flaw detector 71. The above-mentioned flaw detector 71 can receive the test signal, and the processor 72 can realize the processing of the test signal and thus obtain the specific data of the contact stress.

[0033] As Figure 1 shown, in this embodiment, the acoustic wave signal generating device 60 includes an analog signal generator 61 and an analog signal display 62. The above-mentioned analog signal generator 61 can emit acoustic wave signals, and the analog signal display 62 can display acoustic wave signals.

[0034] As Figure 1 shown, in this embodiment, the thread sealing surface contact stress measuring device further includes a pump body 84. The pump body 84 is arranged at the first end of the connecting pipe 82. The above-mentioned pump body 84 can pump the coupling agent towards the test sample to coat the test sample with the coupling agent.

[0035] As Figure 1 shown, in this embodiment, a filling valve 811 is arranged on the container 81, and a transmission valve 821 is arranged on the connecting pipe 82. The above-mentioned filling valve 811 can control the amount of the coupling agent stored in the container, and the transmission valve 821 can control the transmission of the coupling agent.

[0036] According to another aspect of the present application, a method for measuring the contact stress of a threaded sealing surface is provided, which is measured using the above-mentioned device for measuring the contact stress of a threaded sealing surface. As Figure 2 shown, in this embodiment, the method for measuring the contact stress of a threaded sealing surface includes:

[0037] S10: Start the pump body 84 to spray the coupling agent towards the test sample 1 through the connecting pipe 82;

[0038] S20: Fix the sealing surface test structure 20 and the shoulder test structure 30;

[0039] S30: Adjust the measurement angles of the sealing surface test structure 20 and the shoulder test structure 30 through the external thread rotation sensor 40 and the internal thread rotation sensor 50 to obtain a measurement signal;

[0040] S40: Transmit the measurement signal to the data acquisition structure 70 to obtain stress data.

[0041] Specifically, during the test, first, the coupling agent is sprayed on the test sample through the pump body to achieve the conduction of acoustic wave signals between the sealing surface test structure 20 and the shoulder test structure 30 and the test sample 1. Then, the sealing surface test structure 20 and the shoulder test structure 30 are fixed to make the test position more accurate. The measurement angles of the sealing surface test structure 20 and the shoulder test structure 30 are adjusted through the external thread rotation sensor 40 and the internal thread rotation sensor 50 so that the analog signal display 62 can display the acoustic wave signal. Finally, the test signal is transmitted to the data acquisition structure to obtain stress data. After the above steps, the measurement of the test stress on the sealing surface and shoulder of the thread can be effectively achieved.

[0042] As Figure 2 and Figure 3 shown, in this embodiment, S20: The step of fixing the sealing surface test structure 20 and the shoulder test structure 30 includes:

[0043] S21: Clamp the sealing surface test structure 20 and the shoulder test structure 30 on the test sample 1 through the fixture 10;

[0044] S22: The sealing surface test structure 20 and the shoulder test structure 30 are in contact with the test sample 1;

[0045] S23: Slide and adjust the positions of the sealing surface test structure 20 and the shoulder test structure 30 along the axial direction of the test sample 1 and fix them.

[0046] Through the above settings, the fixing of the sealing surface test structure 20 and the shoulder test structure 30 can be effectively achieved. Specifically, the sealing surface test structure 20 and the shoulder test structure 30 are clamped on the outer wall of the collar of the test sample 1 by a fixture 10 with magnetism, and the sealing surface test structure and the shoulder test structure are in contact with the outer wall of the test sample collar.

[0047] As Figure 2 and Figure 4 shown, in this embodiment, S10: The step of starting the pump body 84 to spray the coupling agent towards the test sample 1 through the connecting pipe 82 includes:

[0048] S11: Start the pump body 84 and spray the coupling agent onto the test sample 1;

[0049] S12: When the entire outer surface of the test sample 1 is sprayed, turn off the pump body 84.

[0050] Through the above settings, it can be ensured that the coupling agent is entirely sprayed on the outer surface of the test sample.

[0051] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by orientation words such as "front, back, up, down, left, right", "horizontal, vertical, perpendicular, horizontal" and "top, bottom", etc. is usually based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description. Without contrary description, these orientation words do not indicate and imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation on the protection scope of the present invention; the orientation words "inside, outside" refer to the inside and outside relative to the contour of each component itself.

[0052] For the convenience of description, spatial relative terms such as "above...", "above...", "on the upper surface of...", "above" can be used here to describe the spatial positional relationship between a device or feature shown in the figure and other devices or features. It should be understood that the spatial relative terms are intended to include different orientations in use or operation in addition to the orientation described in the figure for the device. For example, if the device in the drawing is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "beneath other devices or structures" afterwards. Thus, the exemplary term "above..." can include both the orientations of "above..." and "below...". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and corresponding explanations are made for the spatial relative descriptions used here.

[0053] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. Without additional declaration, the above terms have no special meaning, and therefore should not be construed as a limitation on the protection scope of the present invention.

[0054] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A device for measuring the contact stress of a threaded sealing surface, characterized in that, it includes: a fixture (10) for clamping a test sample (1); a sealing surface test structure (20), including a sealing surface test probe, the sealing surface test probe is fixed to the outer wall of the coupling at the sealing surface of the test sample (1), and is used to test the contact stress at the sealing surface of the test sample (1); a shoulder test structure (30), including a shoulder test probe, the shoulder test probe is fixed to the outer wall of the coupling at the shoulder of the test sample (1), and is used to test the contact stress at the shoulder of the test sample (1); an external thread rotation sensor (40) for controlling the rotation angle of the sealing surface test structure (20) and the shoulder test structure (30) relative to the external thread; an internal thread rotation sensor (50) for controlling the rotation angle of the sealing surface test structure (20) and the shoulder test structure (30) relative to the internal thread; an acoustic signal generating device (60), the output end of the acoustic signal generating device (60) is connected to the external thread rotation sensor (40) and the internal thread rotation sensor (50); a data acquisition structure (70) for receiving the signals fed back by the sealing surface test structure (20) and the shoulder test structure (30).

2. The device for measuring the contact stress of a threaded sealing surface according to claim 1, characterized in that, the device for measuring the contact stress of a threaded sealing surface further includes a container (81) and a connecting pipe (82), the inside of the container (81) contains a coupling agent, the first end of the connecting pipe (82) is communicated with the container (81), and the second end of the connecting pipe (82) faces the test sample (1).

3. The device for measuring the contact stress of a threaded sealing surface according to claim 2, characterized in that, the device for measuring the contact stress of a threaded sealing surface further includes a power supply (83), the power supply (83) is connected to the connecting pipe (82) and is used to charge the coupling agent.

4. The device for measuring the contact stress of a threaded sealing surface according to claim 1, characterized in that, the data acquisition structure (70) includes a flaw detector (71) and a processor (72), the flaw detector (71) receives the signal of the data acquisition structure (70), and the processor (72) is connected to the flaw detector (71) and is used to process the measurement signal of the flaw detector (71).

5. The device for measuring the contact stress of a threaded sealing surface according to claim 1, characterized in that, the acoustic signal generating device (60) includes an analog signal generator (61) and an analog signal display (62).

6. The device for measuring the contact stress of a threaded sealing surface according to claim 2, characterized in that, the device for measuring the contact stress of a threaded sealing surface further includes a pump body (84), the pump body (84) is arranged at the first end of the connecting pipe (82).

7. The device for measuring the contact stress of a threaded sealing surface according to claim 2, characterized in that, A filling valve (811) is provided on the container (81), and a transmission valve (821) is provided on the connecting pipe (82).

8. A method for measuring the contact stress of a threaded sealing surface, which is measured by using the device for measuring the contact stress of a threaded sealing surface according to any one of claims 1 to 7, characterized in that the method for measuring the contact stress of a threaded sealing surface includes: starting the pump body (84) to spray the coupling agent through the connecting pipe (82) towards the test sample (1); fixing the sealing surface test structure (20) and the shoulder test structure (30); adjusting the measuring angles of the sealing surface test structure (20) and the shoulder test structure (30) through the external thread rotation sensor (40) and the internal thread rotation sensor (50) to obtain a measuring signal; transmitting the measuring signal to the data acquisition structure (70) to obtain stress data.

9. The method for measuring the contact stress of a threaded sealing surface according to claim 8, characterized in that the step of fixing the sealing surface test structure (20) and the shoulder test structure (30) includes: clamping the sealing surface test structure (20) and the shoulder test structure (30) on the test sample (1) through a fixture (10); the sealing surface test structure (20) and the shoulder test structure (30) are in contact with the test sample (1); sliding axially along the test sample (1) to adjust the positions of the sealing surface test structure (20) and the shoulder test structure (30) and fixing them.

10. The method for measuring the contact stress of a threaded sealing surface according to claim 8, characterized in that the step of starting the pump body (84) to spray the coupling agent through the connecting pipe (82) towards the test sample (1) includes: starting the pump body (84) and spraying the coupling agent towards the test sample (1); closing the pump body (84) when the outer surface of the test sample (1) is completely sprayed.

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