An inspection tool for the non-coincidence degree of the coupling thread axis and its inspection method

Abstract

The present invention discloses an inspection tool for the non - coincidence degree of the coupling thread axis and its inspection method, belonging to the field of oil casing coupling parameter detection. In the inspection tool, the detection unit includes a rod body, an indicating gauge and a detection end. The detection end includes a telescopic measuring rod. A connecting rod is arranged in the rod body. One end of the connecting rod is connected to the pointer of the indicating gauge, and the other end of the connecting rod is connected to the telescopic measuring rod. A detection contact is arranged at the end of the telescopic measuring rod. An inner hole A for passing through the rod body is arranged at the center of the plug gauge A, and an inner hole B for the detection contact to conduct detection is arranged at the center of the plug gauge B. Among them, a position adjustment disc for rotating the rod body is arranged outside the rod body, and an adjustment disc support is arranged between the position adjustment disc and the plug gauge A. During the detection, the rod body is rotated by rotating the position adjustment disc, so that the detection contact moves around on the inner hole wall of the inner hole B. According to the difference value of the scale values on the indicating gauge, the non - coincidence degree of the thread axis of the coupling to be detected is obtained, and it can be applied to the on - site inspection in the oilfield.

Description

Technical Field

[0001] The present invention belongs to the field of parameter detection of oil casing couplings, and particularly relates to an inspection tool and an inspection method for the non - coincidence degree of the coupling thread axis. Background Art

[0002] Oil casing is an important material and equipment used in oil and gas field exploitation, and its quality directly affects the production safety and exploitation efficiency of oil and gas fields. At present, most of the oil casings adopted by major oil fields implement API - related standards, such as API SPEC 5CT and API SPEC 5B, etc. Among them, API SPEC 5B has clearly defined the parameters of oil casing coupling threads and specified the tolerance ranges of various parameters. The manufacturer processes the oil casing according to the product standard requirements, and conducts inspection according to the process to determine the qualified batch products for delivery. The oil field inspection department conducts inspection and verification on the received products according to the standards and the incoming inspection specifications, and only the qualified products can be used downhole.

[0003] In the practical applications of manufacturer production inspection and oil field on - site inspection, it is found that there are few detection means and complex detection tools for some thread parameters of oil casing joints, making it difficult to be actually used at the manufacturing site or the oil field inspection site. For example, for the inspection of the non - coincidence degree of the oil casing coupling axis, API SPEC 5B standard requires that for casing and tubing couplings, the maximum non - coincidence degree of the two - end thread axes measured on the coupling end face shall not exceed 0.031 in (0.79 mm). The standard mentions a bench - type detector, which has a complex structure and many operation steps. It is similar to a laboratory instrument with low detection efficiency and is difficult to be set up and used in oil field on - site inspection. Therefore, it is necessary to propose a convenient tool and method that can be effectively used in oil field on - site inspection to verify whether the non - coincidence degree of the oil casing coupling thread axis meets the standard requirements. Summary of the Invention

[0004] In order to overcome the above - mentioned disadvantages of the prior art, the purpose of the present invention is to provide an inspection tool and an inspection method for the non - coincidence degree of the coupling thread axis, so as to solve the current situation that it is difficult to inspect the non - coincidence degree of the oil casing coupling thread axis in the oil field on - site inspection.

[0005] In order to achieve the above purpose, the present invention adopts the following technical solutions to be realized:

[0006] The present invention discloses an inspection tool for the non - coincidence degree of the coupling thread axes, which includes a plug gauge A, a plug gauge B, and a detection unit; the detection unit includes a rod body, an indicating gauge, and a detection end. The detection end includes a telescopic measuring rod. A connecting rod is arranged inside the rod body. One end of the connecting rod is connected to the pointer of the indicating gauge, and the other end of the connecting rod is connected to the telescopic measuring rod. A detection contact is arranged at the end of the telescopic measuring rod; an inner hole A for passing through the rod body is arranged at the center of the plug gauge A, and an inner hole B for the detection contact to conduct detection is arranged at the center of the plug gauge B; wherein, a position adjustment disc for rotating the rod body is arranged outside the rod body, and an adjustment disc support is arranged between the position adjustment disc and the plug gauge A.

[0007] Preferably, during use, the plug gauge A is assembled at the end A of the coupling of the collar, the plug gauge B is assembled at the end B of the coupling of the collar, the detection unit is passed through the inner hole A and the inner hole B, the indicating gauge is placed outside the plug gauge A, and the telescopic measuring rod is placed on the inner wall of the inner hole B.

[0008] Preferably, the adjustment disc support is a columnar tube with an inner hole at the center, and the inner hole is used for passing through the rod body.

[0009] Further preferably, a positioning groove for cooperating with the outer wall of the columnar tube is arranged outside the plug gauge A.

[0010] Preferably, the position adjustment disc is threadedly connected to the rod body.

[0011] Preferably, a limiting block is arranged on the rod body. One end of the limiting block is fixed to the inner wall of the rod body, and the other end of the limiting block is in contact with the connecting rod. The limiting block is used to keep the connecting rod rotating stably.

[0012] Preferably, a steering device is arranged at one end of the telescopic measuring rod, and the other end of the connecting rod is perpendicularly connected to the telescopic measuring rod through the steering device.

[0013] Further preferably, the telescopic measuring rod includes a multi - section sleeve - type detection rod and a spring. One end of the spring is connected to the steering device, and the other end of the spring is connected to the top of the multi - section sleeve - type detection rod; during use, the spring is in a compressed state, and the multi - section sleeve - type detection rod is in an extended state, so that the detection contact is in contact with the inner wall of the inner hole B.

[0014] Preferably, the plug gauge A and the plug gauge B are assembled at both ends of the collar to be inspected through threaded connection.

[0015] The present invention discloses an inspection method based on the above - mentioned inspection tool for the non - coincidence degree of the coupling thread axes, which includes the following steps:

[0016] 1) Suspend the coupling to be detected vertically in the air. Screw the plug gauge A into the A end of the coupling to be detected, and screw the plug gauge B into the B end of the coupling to be detected. Pass the rod body of the detection unit through the inner hole A and install it in the plug gauge A. Rotate the position adjustment disk to make the rod body continue to pass through the inner hole B and install it in the plug gauge B. Rotate the position adjustment disk to make the detection end of the detection unit flush with the end face of the B end of the coupling. 2) Continue to adjust the up and down position of the rod body by rotating the position adjustment disk to make the detection contact of the detection end flush with the end face of the B end of the coupling. 3) Continue to rotate the rod body by rotating the position adjustment disk to make the detection contact move around on the inner hole wall of the inner hole B. According to the difference in the scale values on the indicating gauge, obtain the non - coincidence degree of the thread axes of the coupling to be detected.

[0017] Preferably, in step 3), obtaining the non - coincidence degree of the thread axes of the coupling to be detected according to the difference in the scale values on the indicating gauge specifically includes the operations:

[0018] Make the detection contact move around on the inner hole wall of the inner hole B for one week, and record the minimum scale S1 and the maximum scale S2 on the indicating gauge. Then, for the non - coincidence degree S of the thread axes of the coupling to be detected, its calculation general formula is as follows:

[0019] S = S2 - S1.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] The present invention discloses an inspection tool for the non - coincidence degree of the thread axes of a coupling. Through the detection end composed of a telescopic measuring rod, it can realize the inspection of the non - coincidence degree within a certain axial height range, avoid the replacement of structural equipment, and is applicable to a larger inspection range. By arranging a connecting rod in the rod body and directly connecting one end of the connecting rod to the pointer of the indicating gauge, it can directly display the degree of non - coincidence. By setting a position adjustment disk that drives the rod body to rotate, it can adjust the movement of the detection rod in the axial direction of the coupling, thereby ensuring that couplings of different specifications and sizes can be measured. By setting an adjustment disk support between the position adjustment disk and the plug gauge A, it can fix the axial position of the position adjustment disk with respect to the coupling, so that the axial position of the coupling remains unchanged when the position adjustment disk is rotated. Therefore, the inspection tool for the non - coincidence degree of the thread axes of the coupling of the present invention avoids the need for specially made equipment in the laboratory to measure the non - coincidence degree of the thread axes of the coupling. Its structural design is simple, easy to use and assemble, and can be effectively applied to the manufacturing site or the oilfield inspection site, solving the problem of difficult detection of the non - coincidence degree of the thread axes of the coupling.

[0022] Furthermore, by using a detection rod and a spring to form a telescopic measuring rod, the distance of non - coincidence of the thread axes of the coupling can be obtained.

[0023] Furthermore, by threadedly connecting the position adjustment disc to the rod body, the rotation of the position adjustment disc can be converted into the movement of the rod body in the direction of the coupling axis, avoiding the shaking of the detection end and improving the smoothness and accuracy of detection.

[0024] Furthermore, the detection vertical rod passes through the limit block, and the limit block is fixed on the rod body, enabling the vertical rod to move and rotate axially while remaining unchanged in the radial position, improving the inspection accuracy.

[0025] The present invention also discloses an inspection method for an inspection tool based on the above-mentioned non-coincidence degree of the coupling thread axes. By assembling gauge A and gauge B at both ends of the coupling, the axes of the threads at both ends of the coupling can be aligned with the axes of their respective gauges; by moving the detection contact on the inner wall of inner hole B, driving the pointer of the indicating gauge to rotate, the non-coincidence distance between the axis of gauge B and the axis of gauge A can be measured, thereby obtaining the non-coincidence degree of the coupling thread axes. Therefore, the preparation method has the advantages of simple operation of the detection tool, intuitive data display, and reliable detection results, and can be effectively applied to the manufacturing site or the oilfield inspection site, solving the problems of difficult detection and low detection efficiency of the non-coincidence degree of the coupling thread axes.

[0026] In summary, an inspection tool for the non-coincidence degree of the coupling thread axes and an inspection method based on it disclosed by the present invention have a simple structure, are convenient to carry, are not restricted by the detection environment, can be used both in the oilfield site and the manufacturing workshop, and have extremely strong applicability. Based on the inspection method of this inspection tool, the detection tool is simple to operate, the inspection method has few steps and is easy to master, the inspection result display is intuitive and clear, and it can be determined whether it meets the standard requirements without complex calculations. In addition, the inspection method in the present invention uses the vertical detection of the coupling, effectively avoiding the influence of the tool weight on the detection result and enhancing the accuracy of this detection tool and inspection method. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 is a schematic structural diagram of the inspection tool for the non-coincidence degree of the coupling thread axes of the present invention;

[0028] Figure 2 is a schematic structural diagram of the indicating gauge in the present invention.

[0029] Wherein: 1 - indicating gauge; 2 - position adjustment disc; 3 - adjustment disc support; 4 - gauge A; 5 - end A of the coupling; 6 - rod body; 7 - connecting rod; 8 - detection end; 9 - steering gear; 10 - telescopic measuring rod; 11 - end B of the coupling; 12 - gauge B; 13 - limit block. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0030] To enable those skilled in the art to better understand the solution of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below 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. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0031] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and do not necessarily need to describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances so that the embodiments of the present invention described here can be implemented in an order other than those illustrated or described here. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device comprising a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0032] The present invention will be further described in detail below in conjunction with the accompanying drawings:

[0033] See Figure 1 , which is an inspection tool for the non-coincidence degree of the coupling thread axis disclosed by the present invention. The inspection tool includes two plug gauges A 4 and plug gauges B 12 corresponding to the coupling threads to be measured and a detection unit for detecting the non-coincidence degree. Both the plug gauge A 4 and the plug gauge B 12 are provided with inner holes. The center of the plug gauge A 4 is provided with an inner hole A for passing through the rod body 6, and the center of the plug gauge B 12 is provided with an inner hole B for the telescopic measuring rod 10 to perform detection; the detection unit is installed on the plug gauge A 4 through the inner hole A; specifically, when in use, the plug gauge A 4 is assembled to the coupling A end 5 of the coupling, the plug gauge B 12 is assembled to the coupling B end 11 of the coupling, the detection unit vertically penetrates through the inner hole A and the inner hole B, the indicating gauge 1 is placed outside the plug gauge A 4, the telescopic measuring rod 10 is placed on the inner wall of the inner hole B, and the detection unit can perform axial movement and axial rotation in the inner hole of the plug gauge A 4.

[0034] The detection unit is composed of an indicating gauge 1, a rod body 6, and a detection end 8. The upper end of the rod body 6 is connected to the indicating gauge 1, and the lower end is connected to the detection end 8. The detection end 8 is composed of a telescopic measuring rod 10 and a detection contact provided at one end of the telescopic measuring rod 10.

[0035] Among them, a vertical connecting rod 7 is arranged inside the rod body 6 of the detection unit. The upper end of the vertical connecting rod 7 is connected to the pointer of the dial indicator 1, and the lower end is connected to the other end of the telescopic measuring rod 10 through a steering device 9. A limiting block 13 is arranged on the rod body 6. The limiting block 13 is used to keep the connecting rod 7 stable. One end of the limiting block 13 is fixed to the inner wall of the rod body 6, and the other end of the limiting block 13 is in contact with the connecting rod 7. The limiting block 13 is used to keep the connecting rod 7 rotating stably.

[0036] A section of external thread is arranged on the part of the rod body 6 of the detection unit close to the dial indicator 1, which is matched with the internal thread in the position adjustment disc 2, so as to realize that the position adjustment disc 2 drives the rod body 6 to rotate and adjust the up and down position. An adjustment disc support 3 is arranged between the position adjustment disc 2 and the plug gauge A4. The adjustment disc support 3 is a columnar tube with an inner hole in the center, and the inner hole is used to pass through the rod body 6. Among them, a positioning groove matched with the outer wall of the columnar tube is arranged on the outer side of the plug gauge A4.

[0037] The telescopic measuring rod 10 of the detection end 8 is perpendicular to the connecting rod 7 vertically assembled in the plug gauge A4 and the plug gauge B12. The telescopic measuring rod 10 includes multiple sections of sleeve-type measuring rods and an internal spring. One end of the spring is connected to the steering device 9, and the other end of the spring is connected to the top of the multiple sections of sleeve-type measuring rods. When in use, the spring is in a compressed state, so that the multiple sections of sleeve-type measuring rods are in an extended state, fit with the inner wall of the inner hole B, and expand and contract along the radial direction of the detection unit under the action of the internal spring. The maximum extension can reach the outermost inner wall of the plug gauge B12, and the minimum can be shortened to the innermost inner wall of the plug gauge B12. The steering device 9 of the detection end 8 can convert the horizontal position of the multiple sections of sleeve-type measuring rods into the angular displacement of the vertical connecting rod 7, so as to drive the pointer of the dial indicator 1 to rotate and indicate the value.

[0038] The present invention also discloses an inspection method for the inspection tool based on the misalignment of the coupling thread axes described above. The inspection tool is detected through the following steps:

[0039] Step 1: Vertically suspend the coupling to be inspected, and screw the plug gauge A4 and the plug gauge B12 into the coupling A end 5 (upper end) and the coupling B end 11 (lower end) of the coupling to be inspected respectively.

[0040] Step 2: Pass the rod body 6 of the detection unit through the inner hole A and install it on the plug gauge A4, and adjust the up and down position of the rod body 6 by rotating the position adjustment disc 2, so that the detection contact of the detection end 8 is flush with the end face of the coupling B end 11 to be inspected.

[0041] Step 3: Continue to rotate the rod body 6 by rotating the position adjustment disc 2, so that the detection contact travels around the inner wall of the inner hole B for one week, and record the minimum scale S1 and the maximum scale S2 on the dial indicator 1. As Figure 2 shown.

[0042] Step 4: Calculate the misalignment S of the coupling thread axes through the following formula:

[0043] S = S2 - S1.

[0044] The following further illustrates the present invention with specific embodiments. The provided embodiments are only for clarifying the present invention and not for limiting its scope.

[0045] Example: Taking a coupling for a certain 5-1 / 2" casing with API standard 8-round thread profile as an example, the non-coincidence degree of the coupling thread axis is inspected.

[0046] Step 1: Vertically suspend the coupling to be inspected on the inspection table, and screw the plug gauge A 4 and the plug gauge B 12 into the A end (upper end) and the B end (lower end) of the coupling to be inspected respectively.

[0047] Step 2: Install the rod body 6 of the detection unit on the plug gauge A 4, and adjust the up and down position of the detector by rotating the position adjustment disk 2 so that the detection contact at the end of the retractable measuring rod 10 is flush with the end face of the B end 11 of the coupling to be inspected.

[0048] Step 3: Rotate the detection unit to drive the rod body 6 to make the detection contact travel around the inner hole wall of the plug gauge B 12 for one week, and record that the minimum scale S1 indicated on the dial indicator 1 is 0.15 mm and the maximum scale S2 is 0.19 mm.

[0049] Step 4: Calculate the non-coincidence degree S of the coupling thread axis through the following formula

[0050] S = S2 - S1 = 0.19 - 0.15 = 0.04 mm

[0051] According to the API SPEC 5B standard, it can be found that the maximum non-coincidence degree of the thread axes at both ends of the casing shall not exceed 0.031 in (0.79 mm). The inspection result shows that the non-coincidence degree of the coupling thread axis meets the standard requirements.

[0052] The above-mentioned specific implementation manners further elaborate on the purpose, technical solution and beneficial effects of the present invention. It should be understood that the above is only the specific implementation manner of the present invention and is not used to limit the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An inspection tool for the non - coincidence degree of the axis of a coupling thread, characterized in that, It includes a plug gauge A (4), a plug gauge B (12) and a detection unit; The detection unit includes a rod body (6), an indicating gauge (1) and a detection end (8). The detection end (8) includes a telescopic measuring rod (10). A connecting rod (7) is arranged inside the rod body (6). One end of the connecting rod (7) is connected to the pointer of the indicating gauge (1), and the other end of the connecting rod (7) is connected to the telescopic measuring rod (10). A detection contact is arranged at the end of the telescopic measuring rod (10). An inner hole A for passing through the rod body (6) is arranged at the center of the plug gauge A (4), and an inner hole B for the detection contact to perform detection is arranged at the center of the plug gauge B (12); Wherein, a position adjustment disc (2) for rotating the rod body (6) is arranged outside the rod body (6), and an adjustment disc support (3) is arranged between the position adjustment disc (2) and the plug gauge A (4); The adjustment disc support (3) is a columnar tube with an inner hole at the center, and the inner hole is for passing through the rod body (6); A positioning groove for cooperating with the outer wall of the columnar tube is arranged on the outer side of the plug gauge A (4).

2. The inspection tool for the misalignment degree of the coupling thread axis according to claim 1, wherein The position adjustment disc (2) is threadedly connected to the rod body (6).

3. The inspection tool for the non - coincidence degree of the coupling thread axis according to claim 1, characterized in that, A limiting block (13) is arranged on the rod body (6). One end of the limiting block (13) is fixed to the inner wall of the rod body (6), and the other end of the limiting block (13) is in contact with the connecting rod (7). The limiting block (13) is used to keep the connecting rod (7) rotating stably.

4. The inspection tool for the misalignment degree of the coupling thread axis according to claim 1, characterized in that, One end of the telescopic measuring rod (10) is provided with a steering device (9), and the other end of the connecting rod (7) is perpendicularly connected to the telescopic measuring rod (10) through the steering device (9).

5. The inspection tool for the misalignment degree of the coupling thread axis according to claim 4, characterized in that, The telescopic measuring rod (10) includes a multi-section sleeve-type detection rod and a spring. One end of the spring is connected to the steering device (9), and the other end of the spring is connected to the top of the multi-section sleeve-type detection rod; During use, the spring is in a compressed state, and the multi-section sleeve-type detection rod is in an extended state, so that the detection contact fits against the inner wall of the inner hole B.

6. The inspection tool for the non - coincidence degree of the coupling thread axis according to claim 1, wherein, The plug gauge A (4) and the plug gauge B (12) are assembled at both ends of the coupling to be inspected by threaded connection.

7. The inspection method of an inspection tool for the non - coincidence degree of the coupling thread axis according to any one of claims 1 to 6, characterized in that, It includes the following steps: 1) Vertically suspend the coupling to be detected, screw the plug gauge A (4) into the A end (5) of the coupling to be detected, and screw the plug gauge B (12) into the B end (11) of the coupling to be detected; Pass the rod body (6) of the detection unit through the inner hole A and install it in the plug gauge A (4), and continue to pass the rod body (6) through the inner hole B and install it in the plug gauge B (12) by rotating the position adjustment disc (2); Make the detection end (8) of the detection unit flush with the end face of the B end (11) of the coupling by rotating the position adjustment disc (2); 2) Continue to adjust the up and down position of the rod body (6) by rotating the position adjustment disc (2) to make the detection contact of the detection end (8) flush with the end face of the B end (11) of the coupling; 3) Continue to rotate the rod body (6) by rotating the position adjustment disc (2) to make the detection contact move around on the inner hole wall of the inner hole B, and obtain the non-coincidence degree of the thread axes of the coupling to be detected according to the difference in the scale values on the indicating gauge (1).

8. The inspection method according to claim 7, characterized in that, In step 3), obtaining the non-coincidence degree of the thread axes of the coupling to be detected according to the difference in the scale values on the indicating gauge (1) specifically includes the operations: Rotate the detection contact around the inner wall of the inner hole B for one week, and record the minimum scale S 1 and the maximum scale S 2, then the non - coincidence degree of the thread axes of the coupling to be detected S , and its general calculation formula is as follows: 。

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