Detection die for measuring radius of transition circular arc at root of external thread and use method

Abstract

The invention discloses a detection mold for measuring the radius of a transition arc at the root of an external thread and a use method, and belongs to the technical field of petroleum drilling and production equipment, the detection mold comprises a template conical surface, a template sealing surface and a transition arc, and the template conical surface, the template sealing surface and the transition arc are connected to form a sealing template. The template and the using method are not limited to be used on 5 ''non-standard drill rods, can also be used on various drilling tools such as double-shoulder drilling tool external threads and drill collar threads, and are wide in application range. Meanwhile, the template is similar to a parallelogram structure, two arcs at the opposite angles can be used, the use frequency can be increased, the manufacturing, machining and using methods of the template are very simple, detection is rapid (whether the transition arc of one drilling tool is qualified or not can be judged only in 10 seconds), 100% detection of the transition arc at the root of the external thread of the drilling tool can be rapidly achieved on site, and the detection efficiency is improved. The time cost is not increased while the quality is ensured, the failure is avoided, the drilling accident handling time is saved, and efficient exploration and development of an oil field can be supported.

Description

Technical Field

[0001] The invention belongs to the technical field of petroleum drilling equipment, and in particular relates to a detection die for measuring the transition arc radius of an external thread root and a use method thereof. Background Art

[0002] In 2022, a 5" non-standard drill pipe failed. The drill pipe was put into use on January 4, 2022. After 432.5 hours of pure drilling time and 2273m of footage, on February 24, 2022, during the process of casing dropping and hanging, it was found that there was a crack at the connection between its external thread (the 138th) and the sealing shoulder surface of the lower single internal thread. The crack at the root of the external thread was 210mm long and 5mm wide. After chemical performance, metallographic, microscopic, and stress analysis, it was found that the main reason for the failure of the drill pipe joint was the root of the external thread. The small transition radius leads to stress concentration, which causes the fatigue crack to originate at this place and then cause puncture failure. The transition arc radius of the failed drill pipe external thread root is measured to be 1.1766mm, while the oil field requires the arc radius to be 1.6mm. The transition arc between the drill tool joint and the thread is one of the important parameters affecting the fatigue life of the drill tool. However, the drill tool was not inspected when it arrived for acceptance. The main reason is the lack of inspection tools and detection methods, which leads to the limited life of the drill tool and increased risk factor of the operation. Summary of the invention

[0003] In order to overcome the above-mentioned shortcomings of the prior art, the purpose of the present invention is to provide a detection template and a method of use for measuring the transition arc radius of the root of an external thread, so as to solve the technical problems of limited drilling tool life and increased operation risk factor in the prior art.

[0004] In order to achieve the above object, the present invention adopts the following technical solutions:

[0005] A detection mold for measuring the transition arc radius of the root of an external thread comprises: a template conical surface, one end of the template conical surface is connected to the transition arc and then to the template sealing surface, and the other end is directly connected to the template sealing surface. The template conical surface, the template sealing surface and the transition arc are connected to form a sealing template.

[0006] Preferably, the taper of the template conical surface is 1:4 or 1:6.

[0007] Preferably, the template conical surface, the template sealing surface and the transition arc are connected to form a sealing template which is a parallelogram with one rounded corner.

[0008] Preferably, the template sealing surface is perpendicular to the thread axis of the measured component.

[0009] Preferably, the transition arc is tangent to the template conical surface and the template sealing surface.

[0010] Preferably, the radius of the transition arc is 0.8-2.0 mm.

[0011] The present invention also discloses a method for using a detection die for measuring the transition arc radius of the root of an external thread, comprising the following steps:

[0012] Fit the template sealing surface to the main thread sealing surface of the tested part;

[0013] Place the transition arc close to the thread arc of the tested part;

[0014] Observe the fit between the template cone surface and the thread cone surface of the tested part to determine whether the tested part is qualified.

[0015] Preferably, the tested part is judged to be qualified when the fitting condition between the template conical surface and the tested part thread conical surface is that the template conical surface and the tested part thread conical surface are matched and the transition arc fits the tested part thread arc.

[0016] Preferably, according to the fitting condition between the template conical surface and the measured piece thread conical surface, when the template conical surface and the measured piece thread conical surface match but the transition arc and the measured piece thread arc do not fit, the measured piece is judged to be unqualified.

[0017] Preferably, when the fitting condition between the template conical surface and the thread conical surface of the measured piece is that the template conical surface and the thread conical surface of the measured piece do not fit each other and a gap is left, the measured piece is judged to be qualified.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] The present invention discloses a detection mold for measuring the radius of the transition arc at the root of an external thread. The template conical surface, the template sealing surface and the transition arc are connected to form a sealing template. The template sealing surface fits the main sealing surface of the thread of the tested piece. By comparing whether the transition arc fits the thread arc of the tested piece, and the fit between the template conical surface and the thread conical surface of the tested piece, it is judged whether the tested piece reduces the stress concentration at the thread arc of the tested piece and whether the tested piece meets the design requirements, thereby most effectively improving the fatigue life of the tested piece, improving the life of the drilling tool, and reducing the operation risk factor. Moreover, the template is not limited to being used on 5" non-standard drill pipes, but can also be used on various drilling tools such as double-shoulder drilling tool external threads and drill collar threads. It has a wide range of applications and rapid detection. The transition arc at the root of the external thread of the drilling tool can be quickly inspected 100% on site, which can ensure quality without increasing time costs, avoid the occurrence of the above-mentioned failures, save drilling accident processing time, and support efficient exploration and development of oil fields.

[0020] Furthermore, the template conical surface, template sealing surface and transition arc are connected to form a sealing template which is a parallelogram with rounded corners. The two arcs at the diagonals are designed to be usable, which can increase the number of uses.

[0021] The method for using the detection mold for measuring the transition arc radius of the root of the external thread disclosed in the present invention is not limited to being used on 5" non-standard drill pipes, but can also be used on various drilling tools such as double-shoulder drilling tool external threads and drill collar threads. The scope of application is wide, and the method of use is simple and the detection is rapid (it only takes 10 seconds to determine whether the transition arc of a drilling tool is qualified). The transition arc of the root of the external thread of the drilling tool can be 100% inspected quickly on site, and the quality can be ensured without increasing the time cost, avoiding the occurrence of the above-mentioned failure, saving the time for handling drilling accidents, and supporting the efficient exploration and development of oil fields. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the mold structure of the present invention;

[0023] Figure 2 is a flow chart of the method of using the present invention;

[0024] Figure 3 A diagram showing the measurement conditions of the present invention;

[0025] Figure 4 Figure 2 is a measurement situation of the present invention;

[0026] Figure 5 Three diagrams showing the measurement conditions of the present invention;

[0027] Figure 6 Four diagrams showing the measurement conditions of the present invention;

[0028] Figure 7 This is a schematic diagram of the mold structure used in an embodiment of the present invention.

[0029] Among them: 1-template cone surface; 2-template sealing surface; 3-transition arc; 4-thread cone surface; 5-thread sealing surface; 6-thread arc. DETAILED DESCRIPTION

[0030] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme 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 only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection 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 are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

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

[0033] See also Figure 1 The present invention discloses a detection mold for measuring the radius of the transition arc at the root of an external thread, comprising: a template conical surface 1, one end of the template conical surface 1 is connected to the transition arc 3 and then to the template sealing surface 2, and the other end is directly connected to the template sealing surface 2, and the template conical surface 1, the template sealing surface 2 and the transition arc 3 are connected to form a sealing template. The template sealing surface 2 fits with the main sealing surface of the thread of the measured part, and by comparing whether the transition arc 3 fits with the thread arc of the measured part, and the fit of the template conical surface 1 and the thread conical surface of the measured part, it is judged whether the measured part reduces the stress concentration at the thread arc of the measured part, and whether the measured part meets the design requirements, thereby most effectively improving the fatigue life of the measured part, improving the life of the drilling tool, and reducing the risk factor of the operation. The template is not limited to 5" non-standard drill pipes, but can also be used on double-shoulder drill tool external threads, drill collar threads and other drill tools. It has a wide range of applications and rapid detection. The transition arc at the root of the external thread of the drill tool can be quickly inspected on site for 100%, which can ensure quality without increasing time costs, avoid the occurrence of the above-mentioned failures, save drilling accident handling time, and support efficient exploration and development of oil fields.

[0034] The most effective way to improve fatigue life is to keep the designed structure at a lower stress level. The requirement for structural design is to reduce stress concentration. Literature shows that in the structural design details, under the conditions of space, weight and other actual conditions, the largest possible angle R should be used, especially where the cross-sectional thickness changes, to reduce the adverse effects of stress concentration. Based on this theory, when the measured arc radius R ≥ the arc radius R specified in the design drawing or standard, the measurement result is considered qualified, otherwise it is judged as unqualified.

[0035] In some embodiments, the taper of the template conical surface 1 is 1:4 or 1:6.

[0036] In some embodiments, the template conical surface 1, the template sealing surface 2 and the transition arc 3 are connected to form a sealing template which is a parallelogram with rounded corners.

[0037] In some embodiments, the template sealing surface 2 is perpendicular to the thread axis of the measured component.

[0038] In some embodiments, the transition arc 3 is tangent to the template cone surface 1 and the template sealing surface 2 .

[0039] In some embodiments, the arc radius of the transition arc 3 is 0.8-2.0 mm.

[0040] In some embodiments, in order to avoid the template from causing damage to the arc during detection and considering the wear resistance of the template for long-term use, high-strength plastic or steel plate ≤ joint strength (120 steel grade) can be selected, with a thickness of 5 mm, a width of 15 mm, and a length of 25.4 mm;

[0041] In some embodiments, the template is similar to a parallelogram structure. In order to increase the number of times the template can be used, the two diagonal arcs R can be used.

[0042] See also Figure 2 The present invention also discloses a method for using a detection die for measuring the transition arc radius of the root of an external thread, comprising the following steps:

[0043] S1: Fit the template sealing surface 2 to the main sealing surface of the thread of the tested part;

[0044] S2: Move the transition arc 3 close to the thread arc of the tested part;

[0045] S3: Observe the fit between the template cone surface 1 and the thread cone surface of the tested part to determine whether the tested part is qualified.

[0046] The method of use is not limited to the use on 5" non-standard drill pipes, but can also be used on double-shoulder drill tool external threads, drill collar threads and other drill tools, with a wide range of applications. At the same time, the template is similar to a parallelogram structure, and its two diagonal arcs can be used, which can increase the number of uses. Its manufacturing, processing and use methods are very simple, and the detection is fast (it only takes 10 seconds to determine whether the transition arc of a drill tool is qualified). The transition arc at the root of the external thread of the drill tool can be quickly inspected 100% on site, which can ensure quality without increasing time costs, avoid the occurrence of the above-mentioned failures, save drilling accident processing time, and support efficient exploration and development of oil fields.

[0047] The following four situations occur during measurement:

[0048] In some embodiments, case 1, see Figure 3: Measured value = design value, that is, the template cone surface 1 and the thread cone surface basically coincide, the template sealing surface 2 and the thread main sealing surface basically fit, and the arc chamfer also fits, which is considered qualified;

[0049] In some embodiments, case 2, see Figure 4 : The measured value is less than the design value, that is, the template cone surface 1 matches the thread cone surface, the template sealing surface 2 fits the thread main sealing surface, but the template arc does not fit the thread arc, and there is an obvious gap during the test. This situation is judged as unqualified and should be marked;

[0050] In some embodiments, case three, see Figure 5 : Measured value > design value, that is, when the template sealing surface 2 fits with the main thread sealing surface, there is a gap between the template cone surface 1 and the thread cone surface, which can better reduce the stress concentration at this location and is judged to be qualified.

[0051] In some embodiments, case four, see Figure 6 : Measured value > design value. When the template cone surface 1 fits with the thread cone surface, there is a gap between the template sealing surface 2 and the thread sealing surface, which can better reduce the stress concentration at this location and is judged to be qualified.

[0052] It only takes 10 seconds to determine whether the transition arc of a drill bit is qualified. The detection is rapid, and the transition arc of the root of the external thread of the drill bit can be quickly inspected 100% at the operation site, which can ensure the quality without increasing the time cost, avoid the occurrence of the above-mentioned failures, save the time for handling drilling accidents, and support the efficient exploration and development of oil fields.

[0053] [Example 1]

[0054] Take the 5" tower drill pipe, an independent innovation product of the oil field, as an example, see Figure 7 The design of the detection template structure dimensions is as follows: the taper of the template cone surface 1 in the figure is 1:6; the template sealing surface 2 is perpendicular to the thread axis, the transition arc radius R is 1.6mm, the template width is 15mm, the height is 25.4mm, and the thickness is 5mm.

[0055] Directions:

[0056] S1: Fit the template sealing surface 2 to the main sealing surface of the thread of the tested part;

[0057] S2: Move the transition arc 3 close to the thread arc of the tested part;

[0058] S3: Observe the fit between the template cone surface 1 and the thread cone surface of the tested part to determine whether the tested part is qualified.

[0059] Use this template to detect, see Figure 3: Measured value = design value, that is, the template cone surface 1 and the thread cone surface basically coincide, the template sealing surface 2 and the thread main sealing surface basically fit, and the arc chamfer also fits, which is considered qualified;

[0060] [Example 2]

[0061] Take the 5" tower drill pipe, an independent innovation product of the oil field, as an example, see Figure 7 The design of the detection template structure dimensions is as follows: the taper of the template cone surface 1 in the figure is 1:6; the template sealing surface 2 is perpendicular to the thread axis, the transition arc radius R is 1.6mm, the template width is 15mm, the height is 25.4mm, and the thickness is 5mm.

[0062] Directions:

[0063] S1: Fit the template sealing surface 2 to the main sealing surface of the thread of the tested part;

[0064] S2: Move the transition arc 3 close to the thread arc of the tested part;

[0065] S3: Observe the fit between the template cone surface 1 and the thread cone surface of the tested part to determine whether the tested part is qualified.

[0066] Use this template to detect, see Figure 4 : The measured value is less than the design value, that is, the template cone surface 1 matches the thread cone surface, the template sealing surface 2 fits the thread main sealing surface, but the template arc does not fit the thread arc, and there is an obvious gap during the test. This situation is judged as unqualified and should be marked;

[0067] [Example 3]

[0068] Take the 5" tower drill pipe, an independent innovation product of the oil field, as an example, see Figure 7 The design of the detection template structure dimensions is as follows: the taper of the template cone surface 1 in the figure is 1:6; the template sealing surface 2 is perpendicular to the thread axis, the transition arc radius R is 1.6mm, the template width is 15mm, the height is 25.4mm, and the thickness is 5mm.

[0069] Directions:

[0070] S1: Fit the template sealing surface 2 to the main sealing surface of the thread of the tested part;

[0071] S2: Move the transition arc 3 close to the thread arc of the tested part;

[0072] S3: Observe the fit between the template cone surface 1 and the thread cone surface of the tested part to determine whether the tested part is qualified.

[0073] Use this template to detect, see Figure 5, the measured value > the design value, that is, when the template sealing surface 2 fits with the main thread sealing surface, there is a gap between the template cone surface 1 and the thread cone surface, which can better reduce the stress concentration at this location and is judged to be qualified.

[0074] [Example 4]

[0075] Take the 5" tower drill pipe, an independent innovation product of the oil field, as an example, see Figure 7 The design of the detection template structure dimensions is as follows: the taper of the template cone surface 1 in the figure is 1:6; the template sealing surface 2 is perpendicular to the thread axis, the transition arc radius R is 1.6mm, the template width is 15mm, the height is 25.4mm, and the thickness is 5mm.

[0076] Directions:

[0077] S1: Fit the template sealing surface 2 to the main sealing surface of the thread of the tested part;

[0078] S2: Move the transition arc 3 close to the thread arc of the tested part;

[0079] S3: Observe the fit between the template cone surface 1 and the thread cone surface of the tested part to determine whether the tested part is qualified.

[0080] Use this template to detect, see Figure 6 : Measured value > design value. When the template cone surface 1 fits with the thread cone surface, there is a gap between the template sealing surface 2 and the thread sealing surface, which can better reduce the stress concentration at this location and is judged to be qualified.

[0081] The template and its use method are not limited to use on 5" non-standard drill pipes, but can also be used on double-shoulder drill tool external threads, drill collar threads and other drill tools, with a wide range of applications. At the same time, the template is similar to a parallelogram structure, and its two diagonal arcs can be used, which can increase the number of uses. Its manufacturing, processing and use methods are very simple, and the detection is rapid (it only takes 10 seconds to determine whether the transition arc of a drill tool is qualified). The transition arc at the root of the external thread of the drill tool can be quickly inspected 100% on site, which can ensure quality without increasing time costs, avoid the occurrence of the above-mentioned failures, save drilling accident processing time, and support efficient exploration and development of oil fields.

[0082] The above contents are only for explaining the technical idea of ​​the present invention and cannot be used to limit the protection scope of the present invention. Any changes made on the basis of the technical solution in accordance with the technical idea proposed by the present invention shall fall within the protection scope of the claims of the present invention.

Claims

1. A detection die for measuring the transition arc radius of the root of an external thread, characterized in that: include: The template conical surface (1) has one end connected to the transition arc (3) and then connected to the template sealing surface (2), and the other end directly connected to the template sealing surface (2). The template conical surface (1), the template sealing surface (2) and the transition arc (3) are connected to form a sealing template.

2. A detection die for measuring the transition arc radius of the root of an external thread according to claim 1, characterized in that: The taper of the template conical surface (1) is 1:4 or 1:

6.

3. The detection die for measuring the transition arc radius of the root of an external thread according to claim 1, characterized in that: The template conical surface (1), the template sealing surface (2) and the transition arc (3) are connected to form a sealing template which is a parallelogram with one rounded corner.

4. The detection die for measuring the transition arc radius of the root of an external thread according to claim 1, characterized in that: The template sealing surface (2) is perpendicular to the thread axis of the component being tested.

5. The detection die for measuring the transition arc radius of the root of an external thread according to claim 1, characterized in that: The transition arc (3) is tangent to the template conical surface (1) and the template sealing surface (2).

6. The detection die for measuring the transition arc radius of the root of an external thread according to claim 1, characterized in that: The arc radius of the transition arc (3) is 0.8-2.0 mm.

7. A method for using a detection die for measuring the transition arc radius of an external thread root as claimed in any one of claims 1 to 6, characterized in that: The following steps are involved: Fitting the template sealing surface (2) to the main thread sealing surface of the tested piece; Place the transition arc (3) close to the thread arc of the tested object; Observe the fit between the template cone surface (1) and the thread cone surface of the tested piece to determine whether the tested piece is qualified.

8. The method for using a detection die for measuring the transition arc radius of the root of an external thread according to claim 7, characterized in that: The test piece is judged to be qualified when the template conical surface (1) and the test piece thread conical surface fit together and the transition arc (3) fits the test piece thread arc according to the fitting condition between the template conical surface (1) and the test piece thread conical surface.

9. The method for using a detection die for measuring the transition arc radius of the root of an external thread according to claim 7, characterized in that: According to the fitting condition between the template conical surface (1) and the thread conical surface of the tested piece, when the template conical surface (1) and the thread conical surface of the tested piece fit together but the transition arc (3) does not fit the thread arc of the tested piece, the tested piece is judged to be unqualified.

10. The method for using a detection die for measuring the transition arc radius of the root of an external thread according to claim 7, characterized in that: The test piece is judged to be qualified when the template conical surface (1) and the test piece thread conical surface are not in contact with each other and a gap is left according to the contact condition between the template conical surface (1) and the test piece thread conical surface.

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