Oil well tubular column power tong torque precision detection nipple and method

Abstract

The invention belongs to the technical field of testing devices, and particularly relates to an oil well tubular column power tong torque precision detection short section and method, and the short section comprises an external thread section and an internal thread section which are connected with each other, and a power tong for clamping the external thread section and the internal thread section; a pressure-bearing piece and a spring assembly are arranged at the thread matching position of the internal thread section and the external thread section, a pressure sensor is installed on the back face of the spring assembly and connected with a signal processing system through a transmission cable, and the signal processing system is connected with a display screen. The screwing-on torque which is not easy to detect in the screwing-on process of threaded connection is converted into the detectable pre-tightening force, then the value of the screwing-on torque borne by the detection short section is obtained through inversion calculation of the pre-tightening force, then the value is displayed on the displayer in the form of data, the influence of a tong torque transmission system on the output torque can be effectively avoided, and the detection accuracy is improved. And the output torque value of the power tongs can be detected more accurately, so that the precision of the power tongs can be detected.

Description

Technical Field

[0001] The invention belongs to the technical field of testing devices, and in particular relates to a torque accuracy detection nipple and a method for a power tong for an oil well pipe string. Background Art

[0002] Oil well pipes (casing, tubing and drill pipe) are indispensable and important tools in the exploration and exploitation of oil and gas. The drill pipe is connected in series to form the entire drill pipe string by threaded connection, providing a channel for mud transportation for drilling operations, and a carrier for drilling pressure and torque transmission. The casing is connected in series to form the entire casing string by threaded connection, fixing the entire wellbore channel and providing a stable transportation channel for oil and gas transportation. The oil pipe is connected in series to form the entire oil pipe string by threaded connection, placed in the annulus of the casing string, connected to the wellhead Christmas tree, and is a direct runway for oil and gas transportation. Therefore, whether it is a drill pipe string, an oil pipe string or a casing string, threaded connection is an important means to form these pipe strings. Therefore, the strength and sealing performance of the threaded connection directly affect the state of the entire pipe string. At the same time, drill pipe strings, tubing strings and casing strings are subjected to high temperature, high pressure, external extrusion, bending, torsion and other composite loads during service. As the connection between pipe fittings, the connection and sealing performance of threaded connections are not only related to the service conditions and environment, but also to the processing quality, make-up operation, accessory products (thread grease) and lifting and lowering operations of threaded connections. Among them, reasonable make-up torque has an important influence on the connection strength and sealing performance of oil well pipe threaded connections. In the actual use of oil well pipe strings, threaded connections often have sticking, puncture leakage and fracture failure accidents. Too small or too large make-up torque is often an important factor leading to its failure. Power tongs are important tools for threaded connection of oil well pipes. The existing technology still uses the traditional calibration method for power tongs, that is, checking sensors and hydraulic gauges. This method only detects and calibrates the accuracy of a single component. Its disadvantage is that it does not consider the influence of the torque transmission system of the entire tongs on the output torque. When hydraulic system leakage, sensor loosening, wear and loosening of the mating surfaces between transmission parts, etc. occur, even if the accuracy of the hydraulic gauge and the accuracy of the sensor are still in good condition, the output torque has deviated from the theoretical calculation result (the displayed value on the torque display). Therefore, the existing torque detection method of power tongs cannot truly reflect the actual torque acting on the threaded connection of oil well pipes. Summary of the invention

[0003] In order to solve or partially solve the above problems, the present invention proposes a torque accuracy detection nipple of a power tong for oil well tubulars, comprising an external thread section and an internal thread section connected to each other, and a power tong for clamping the external thread section and the internal thread section;

[0004] A pressure-bearing part and a spring assembly are arranged at the threaded fitting position of the internal thread section and the external thread section, a pressure sensor is installed on the back of the spring assembly, the pressure sensor is connected to a signal processing system via a transmission cable, and the signal processing system is connected to a display screen.

[0005] Furthermore, the external thread section and the internal thread section are hollow cylindrical sections, the external thread at the end of the external thread section and the thread of the internal thread section are cylindrical threads, and the internal thread and the external thread match each other.

[0006] Furthermore, the power tongs include a main tong and a backup tong;

[0007] Wherein, the main tongs clamp the external thread segment body, and the backup tongs clamp the internal thread segment body.

[0008] Furthermore, the power tongs also include a torque display, which is installed on the body of the power tongs and is used to display the torque generated by the power tongs.

[0009] Furthermore, the pressure-bearing member and the spring assembly are arranged inside the internal thread section;

[0010] Wherein, the spring assembly is arranged at one end close to the external thread section, and the pressure-bearing member is arranged at one end close to the internal thread section.

[0011] Furthermore, the pressure-bearing member is composed of an upper support ring, a lower support ring and a pressure-bearing ball; the upper support ring can roll freely on the surface of the pressure-bearing ball, and the lower support ring supports and fixes the rolling bearing.

[0012] Further, the spring assembly includes a compression spring.

[0013] On the other hand, the present invention proposes a method for detecting the torque accuracy of a power tong for a well tubular column, which uses the torque accuracy detection nipple of the power tong for a well tubular column to perform detection, and comprises the following steps:

[0014] Clamp the external thread segment and the internal thread segment with the main tongs and backup tongs of the power tongs respectively, and apply a specific torque according to the testing requirements;

[0015] The torque generated by the power tongs is transmitted to the internal thread section, and the pressure-bearing part in the internal thread section converts the torque into axial pressure of the pressure-bearing part and transmits the pressure to the spring assembly, and the spring assembly is elastically deformed by the axial pressure;

[0016] After the pressure sensor senses the pressure generated by the deformation of the spring assembly, it transmits the pressure value signal to the signal processing system through the transmission cable;

[0017] The signal processing system converts the pressure value signal transmitted by the pressure sensor into the make-up torque value data of the detection pup joint and displays it on the display screen.

[0018] Furthermore, the method also includes displaying the torque output by the power tongs on a torque display.

[0019] Beneficial effects of the present invention:

[0020] The torque accuracy test section for power tongs proposed in the present invention converts the make-up torque that is not easy to detect during the make-up process of the threaded connection into a detectable preload, and then obtains the make-up torque value on the test section by inverse calculation of the preload, and displays it on the display in the form of data, thereby realizing the detection of the torque value accuracy of the power tongs. Compared with the solution in the prior art that detects and calibrates the accuracy of individual components such as sensors and hydraulic gauges of the power tongs, the solution proposed in the present invention effectively avoids the influence of the tongs torque transmission system on the output torque, and can more accurately detect the output torque value of the power tongs, thereby detecting the accuracy of the power tongs.

[0021] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures pointed out in the description, claims and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] 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 some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0023] Figure 1 It shows a schematic structural diagram of a torque accuracy detection sub for a power tongs proposed in an embodiment of the present invention;

[0024] Figure 2 It shows a schematic structural diagram of a pressure-bearing component of a power tongs provided by an embodiment of the present invention;

[0025] Figure 3 A schematic diagram showing a detection operation of a power tong performed by a detection sub provided by an embodiment of the present invention;

[0026] Figure 4 A flow chart of a method for detecting torque accuracy of a power tong for a tubular column in an oil well according to an embodiment of the present invention is shown;

[0027] In the figure, 1. external thread section; 2. internal thread section; 3. pressure-bearing part; 31. upper support ring; 32. lower support ring; 33. pressure-bearing ball; 4. spring assembly; 5. pressure sensor; 6. signal processing system; 7. display screen; 8. power supply; 9. transmission cable; 10. power tongs; 101. main tongs; 102. backup tongs; 103. torque display. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are 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 creative work are within the scope of protection of the present invention.

[0029] The design principle of the oil well pipe string power tongs is to convert the hydraulic pressure into the torsional force of the power tongs by combining the hydraulic pressure with the transmission mechanism, thereby applying torque power to the oil well pipe string to realize the threaded connection and unthreading of the oil well pipe string. Therefore, in order to avoid accidents such as sticking, leakage and fracture failure of the threaded connection of the oil well pipe string during use, it is necessary to regularly calibrate the make-up torque applied by the oil well pipe string threaded connection tool. However, since the calibration of the power tongs in the prior art still adopts the traditional calibration method, there is a problem that the output torque test of the power tongs is not accurate enough. In order to solve the problem of inaccurate calibration of the output torque of the power tongs in the prior art. The embodiment of the present invention provides a torque accuracy detection short section of the power tongs. Since the torque can be converted into tension or pressure between the contact surfaces in the threaded connection, so that the two workpieces are firmly assembled together, the make-up torque can make the threaded connection move axially, thereby squeezing the pressure-bearing part (preload), and the torque is reversed by the pressure sensed by the sensor. Based on this, the present invention adopts an actual threaded connection structure, converts the make-up torque that is not easy to detect during the threaded connection process into a detectable preload, and then obtains the make-up torque value on the detection short section through inverse calculation of the preload, and displays it on the display in the form of data, thereby realizing the detection of the torque value accuracy of the power tongs. The specific technical solution is as follows:

[0030] This embodiment provides a torque accuracy detection short section of a power tongs 10, such as Figure 1As shown, it includes an external thread segment 1 and an internal thread segment 2, and a pressure-bearing member 3 and a spring assembly 4 are arranged at the threaded connection between the internal thread segment 2 and the external thread segment 1. Specifically, the pressure-bearing member 3 and the spring assembly 4 are arranged inside the internal thread segment 2, wherein the spring assembly 4 is arranged at one end close to the external thread segment 1, and the pressure-bearing member 3 is arranged at one end close to the internal thread segment 2. The pressure-bearing member 3 converts the make-up torque between the internal thread segment 2 and the external thread segment 1 into the axial pressure of the pressure-bearing member 3, and transmits it to the spring assembly 4, and the spring assembly 4 can be elastically deformed when axially compressed. A pressure sensor 5 is installed on the back of the spring assembly 4, and the pressure sensor 5 is connected to the signal processing system 6 through a transmission cable 9. The pressure sensor 5 can sense the pressure value of the spring assembly 4 under compression and transmit the signal to the signal processing system 6 through the transmission cable 9. The signal processing system 6 is connected to a display screen 7, which is used to display the torque value transmitted from the signal processing system 6 on the display screen 7, and the power supply 8 provides a power source for the signal processing system 6 and the display.

[0031] In some exemplary embodiments, the body of the external thread segment 1 and the body of the internal thread segment 2 are the main tong 101 clamping area and the back tong 102 clamping area of ​​the power tong 10. The external thread segment 1 and the internal thread segment 2 are hollow cylindrical segments, the external thread at the end of the external thread segment 1 and the thread of the internal thread segment 2 are cylindrical threads, and the internal thread and the external thread match each other. The use of cylindrical threads can sense the pressure of all torque conversions to ensure the accuracy of detection.

[0032] In some exemplary embodiments, the spring assembly 4 is a compression spring.

[0033] In some exemplary embodiments, the signal processing system 6 may convert the pressure value signal transmitted by the pressure sensor 5 into the make-up torque value data of the detection nipple.

[0034] In some exemplary embodiments, Figure 2 As shown, the pressure-bearing member 3 is composed of an upper support ring 31, a lower support ring 32 and pressure-bearing balls 33; the upper support ring 31 can roll freely on the surface of the pressure-bearing balls 33, and the lower support ring 32 supports and fixes the rolling bearing.

[0035] In some exemplary embodiments, the body of the external thread segment 1 and the body of the internal thread segment 2 are the main clamping area 101 and the back-up clamping area 102 of the power tongs 10; Figure 3 As shown, the power tongs 10 include a main tongs 101, a backup tongs 102 and a torque display 103, wherein the main tongs 101 clamp the body of the external thread segment 1, the backup tongs 102 clamp the body of the internal thread segment 2, and the torque display 103 is used to display the torque generated by the power tongs 10.

[0036] In an optional embodiment, the pressure sensor 5 is disposed on the spring assembly 4 to sense the pressure value of the spring assembly 4 under compressive deformation, and transmits the pressure value signal to the signal processing system 6 through the transmission cable 9 .

[0037] In an optional embodiment, the display screen 7 is connected to the signal processing system 6 , and the torque value transmitted from the signal processing system 6 is displayed on the display screen 7 .

[0038] In an optional embodiment, the power supply 8 provides a power source for the signal processing system 6 and the display.

[0039] The present invention also proposes a method for detecting the torque accuracy of a power tong 10 of an oil well pipe string, such as Figure 4 As shown, the specific steps are as follows:

[0040] The main tongs 101 and the backup tongs 102 of the power tongs 10 clamp the external thread segment 1 and the internal thread segment 2 respectively, and apply a specific torque according to the detection requirements; the torque display 103 is used to display the torque output by the power tongs 10;

[0041] The torque generated by the power tongs 10 is transmitted to the internal thread section 2, and the pressure-bearing member 3 in the internal thread section 2 converts the torque into an axial pressure of the pressure-bearing member 3, and transmits the pressure to the spring assembly 4, and the spring assembly 4 is elastically deformed by the axial pressure;

[0042] After the pressure sensor 5 senses the pressure value generated by the elastic deformation of the spring assembly 4, the pressure value signal is transmitted to the signal processing system 6 through the transmission cable 9;

[0043] The signal processing system 6 converts the pressure value signal transmitted by the pressure sensor 5 into the make-up torque value data of the detection pup joint and displays it on the display screen 7.

[0044] It should be noted that, in the present invention, the terms "upper", "lower", "left", "right", "front", "back", "top", "bottom", "inside", "outside", "middle", "vertical", "horizontal", "lateral", "longitudinal" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings. Although the present invention has been described in detail with reference to the aforementioned embodiments, a person of ordinary skill in the art should understand that the technical solutions described in the aforementioned embodiments can still be modified, or some of the technical features thereof can be replaced by equivalents; and these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A torque precision detection sub for a power tong in an oil well pipe string, characterized in that: It comprises an external thread segment (1) and an internal thread segment (2) connected to each other, and a power tongs (10) for clamping the external thread segment (1) and the internal thread segment (2); A pressure-bearing part (3) and a spring assembly (4) are arranged at the threaded joint of the internal thread section (2) and the external thread section (1); a pressure sensor (5) is installed on the back of the spring assembly (4); the pressure sensor (5) is connected to a signal processing system (6) via a transmission cable (9); and the signal processing system (6) is connected to a display screen (7).

2. The oil well pipe string power tongs torque accuracy detection nipple according to claim 1, characterized in that: The external thread section (1) and the internal thread section (2) are hollow cylindrical sections, the external thread at the end of the external thread section (1) and the thread of the internal thread section (2) are cylindrical threads, and the internal thread and the external thread match each other.

3. The oil well pipe string power tongs torque accuracy detection nipple according to claim 1, characterized in that: The power tongs (10) comprise a main tongs (101) and a backup tongs (102); The main clamp (101) clamps the body of the external threaded section (1), and the backup clamp (102) clamps the body of the internal threaded section (2).

4. The oil well pipe string power tongs torque precision detection nipple according to claim 1, characterized in that: The power tongs (10) further comprises a torque display instrument, which is mounted on the body of the power tongs (10) and is used to display the torque generated by the power tongs (10).

5. The oil well pipe string power tongs torque accuracy detection nipple according to claim 1, characterized in that: The pressure-bearing member (3) and the spring assembly (4) are arranged inside the internal thread section (2); The spring assembly (4) is arranged at one end close to the external thread section (1), and the pressure-bearing member (3) is arranged at one end close to the internal thread section (2).

6. The oil well pipe string power tongs torque accuracy detection nipple according to claim 1, characterized in that: The pressure-bearing member (3) is composed of an upper support ring (31), a lower support ring (32) and a pressure-bearing ball (33); wherein the upper support ring (31) rolls freely on the surface of the pressure-bearing ball (33), and the lower support ring (32) supports and fixes the rolling bearing.

7. The oil well pipe string power tongs torque precision detection nipple according to claim 1, characterized in that: The spring assembly (4) comprises a compression spring.

8. A method for detecting torque accuracy of oil well pipe string dynamic tongs, characterized in that: The detection is performed using the oil well tubular power tong torque accuracy detection nipple according to any one of claims 1 to 7, comprising the following steps: The main clamp (101) and the backup clamp (102) of the power tongs (10) clamp the external thread segment (1) and the internal thread segment (2) respectively, and apply a specific torque according to the detection requirements; The torque generated by the power tongs (10) is transmitted to the internal thread section (2), and the pressure-bearing part (3) in the internal thread section (2) converts the torque into axial pressure of the pressure-bearing part (3), and transmits the pressure to the spring assembly (4), and the spring assembly (4) is elastically deformed by the axial pressure; After the pressure sensor (5) senses the pressure generated by the deformation of the spring assembly (4), it transmits the pressure value signal to the signal processing system (6) through the transmission cable (9); The signal processing system (6) converts the pressure value signal transmitted by the pressure sensor (5) into the make-up torque value data of the detection pup joint and displays it on the display screen (7).

9. The method for detecting torque accuracy of oil well pipe string power tongs according to claim 8, characterized in that: The method further comprises displaying the torque output by the power tongs (10) on a torque display instrument (103).

Images