Air tightness detection device for measurement while drilling instrument

Abstract

The present invention relates to the field of vacuum detection technology, and particularly relates to an airtightness detection device for a measurement-while-drilling instrument, comprising: a base, including a piston sleeve, and a vacuum gauge interface and a detection interface provided on the side wall of the piston sleeve, the vacuum gauge interface, the detection interface and the inner cavity of the piston sleeve are communicated, and the piston sleeve includes a first end and a second end which are communicated; a two-way adapter tube for communicating with a vacuum pumping device, provided at the first end, the vacuum pumping device is communicated with the inner cavity of the piston barrel through the two-way adapter tube, and further communicated with the vacuum gauge interface and the detection interface; a plunger, including a plunger rod and a first piston provided at the end of the plunger rod, the first piston can be hermetically fitted with the first end to disconnect the communication between the vacuum pumping device and the inner cavity of the piston sleeve. The present invention reduces components such as valve switches, avoids air leakage at the valve switches, and improves the reliability and accuracy of airtightness detection.

Description

Technical Field

[0001] The present invention relates to the technical field of vacuum detection, and particularly relates to an airtightness detection device for a measurement-while-drilling instrument. Background Art

[0002] Logging While Drilling (LWD) is a comprehensive logging application technology developed on the basis of Measurement While Drilling (MWD) to solve formation evaluation and drilling geological steering in horizontal wells and multi-branched wells. LWD technology is mainly applied in scenarios such as distinguishing formations, distinguishing water-gas-water, judging formation changes, and predicting high-pressure formations, which can greatly shorten the drilling cycle, reduce the soaking time of water and gas, and reduce the pollution of water-bearing layers. Since the application scenarios of LWD instruments are mostly underground high-pressure test environments, the requirement for airtightness is very high. If the airtightness of the LWD instrument does not meet the requirements, liquid injection is likely to occur underground, which will not only have a significant impact on the measurement results, but also cause irreversible pollution damage to the LWD instrument.

[0003] In order to ensure the qualified and safe operation of LWD instruments underground, airtightness detection needs to be carried out on LWD instruments before each well entry. Therefore, a reliable and portable airtightness detection device for LWD instruments is required to meet the on-site test requirements of LWD instruments. Summary of the Invention

[0004] Aiming at the above problems of the prior art, the purpose of the present invention is to provide an airtightness detection device for a measurement-while-drilling instrument.

[0005] To solve the above problems, the specific technical solution is as follows:

[0006] An airtightness detection device for a measurement-while-drilling instrument includes: a base, including a piston sleeve, and a vacuum gauge interface and a detection interface provided on the side wall of the piston sleeve, the vacuum gauge interface, the detection interface and the inner cavity of the piston sleeve are communicated, and the piston sleeve includes a first end and a second end which are communicated; a two-way adapter tube for communicating with a vacuum pumping device, provided at the first end, the vacuum pumping device is communicated with the inner cavity of the piston barrel through the two-way adapter tube, and then communicated with the vacuum gauge interface and the detection interface; a plunger, including a plunger rod and a first piston provided at the end of the plunger rod, the first piston extends into the inner cavity of the second end, and under the drive of the plunger rod, the first piston can move away from or close to the first end, and the first piston can be in sealing cooperation with the first end to disconnect the communication between the vacuum pumping device and the inner cavity of the piston sleeve.

[0007] Further, the inner diameter of the first end is smaller than the inner diameter of the second end.

[0008] Further, a second piston is also provided on the rod portion of the plunger rod. The second piston is sealingly fitted in the inner cavity of the second end portion. After the first piston is sealingly fitted with the first end portion, the spaces formed by the first piston, the second piston and the piston sleeve are respectively communicated with the vacuum gauge interface and the detection interface.

[0009] Preferably, the two-way adapter tube is provided with a sleeve joint and a vacuum joint. The sleeve joint is sealingly fitted with the first end portion. The first piston is sealingly fitted with the sleeve joint. The vacuum joint extends out of the first end portion.

[0010] Preferably, the airtightness detection device further includes an air extraction pipeline. The air extraction pipeline is sealingly connected with the vacuum joint. The two-way adapter tube is communicated with the vacuum pumping device through the air extraction pipeline.

[0011] Optionally, a vacuum pressure gauge is connected to the vacuum gauge interface. The vacuum pressure gauge is a mechanical vacuum pressure gauge or a digital display vacuum pressure gauge.

[0012] Preferably, a first sealing ring is provided on the first piston, a second sealing ring is provided on the second piston, and a third sealing ring is provided on the detection interface.

[0013] Preferably, the first piston is screwed to the sleeve joint of the two-way adapter tube, and the second piston is screwed to the second end portion.

[0014] On the basis of the above specific embodiments, the usage method of the airtightness detection device includes the steps:

[0015] S1. Sealingly connect the detection interface of the airtightness detection device to the non-magnetic tube of the measurement-while-drilling equipment, and sealingly connect the vacuum pumping device to the two-way adapter tube;

[0016] S2. Apply a pulling force on the plunger to move the first piston away from the first end portion, turn on the vacuum pumping device to extract air, and record the first indication value of the vacuum pressure gauge;

[0017] S3. Apply a pushing force on the plunger to make the first piston sealingly fit with the inner cavity of the first end portion, record the second indication value of the vacuum pressure gauge after exceeding the set time, and judge whether the airtightness of the device to be tested is qualified based on the first indication value and the second indication value.

[0018] Due to the above technical solutions, the present invention has the following beneficial effects:

[0019] Compared with the traditional airtightness detection device, the present invention reduces components such as valve switches, avoids air leakage at the valve switches, and improves the reliability and accuracy of the airtightness detection; in addition, the present invention has a simple and compact structure, a small volume, is convenient for installation and processing, effectively reduces the manufacturing cost and improves the work efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions of the present invention, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0021] Figure 1 It is a schematic structural diagram of the vacuum pumping channel of the airtightness detection device provided by the embodiment of the present invention in the open state;

[0022] Figure 2 is Figure 1 a schematic structural diagram of the device in the closed state of the vacuum pumping channel;

[0023] Figure 3 is Figure 1 an exploded schematic structural diagram of the device.

[0024] In the figure: 1 - base, 2 - measurement - while - drilling equipment, 3 - vacuum pressure gauge, 4 - plunger, 5 - air extraction pipeline, 11 - piston sleeve, 111 - first end, 112 - second end, 113 - opening, 12 - detection interface, 13 - vacuum gauge interface, 14 - two - way adapter, 15 - annular cavity, 21 - first sealing ring, 41 - plunger rod, 42 - first piston, 43 - second piston, 44 - second sealing ring, 45 - third sealing ring, 46 - holding end, 47 - limit snap ring, 48 - positioning clip. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0025] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, rather than all, of the embodiments of the present invention. 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 scope of protection of the present invention.

[0026] It should be noted that the terms "first", "second", etc. in the description, claims and the above-mentioned drawings of the present invention are used to distinguish similar objects and do not necessarily describe a specific order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances 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 "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, device, product or equipment 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 equipment.

[0027] An airtightness detection device for an LWD instrument, comprising: a base 1, including a piston sleeve 11, and a vacuum gauge interface 13 and a detection interface 12 provided on the side wall of the piston sleeve 11. The vacuum gauge interface 13, the detection interface 12 and the inner cavity of the piston sleeve 11 are communicated. The piston sleeve 11 includes a first end 111 and a second end 112 that are communicated; a two-way adapter 14 for communicating with a vacuum pumping device, provided at the first end 111. The vacuum pumping device is communicated with the inner cavity of the piston barrel through the two-way adapter 14, and then communicated with the vacuum gauge interface 13 and the detection interface 12; a plunger 4, including a plunger rod 41 and a first piston 42 provided at the end of the plunger rod 41. The first piston 42 extends into the inner cavity of the second end 112. Driven by the plunger rod 41, the first piston 42 can move away from or close to the first end 111, and the first piston 42 can be in sealing cooperation with the first end 111 to disconnect the communication between the vacuum pumping device and the inner cavity of the piston sleeve 11.

[0028] Preferably, the base 1 is cross-shaped, the piston sleeve 11 is horizontally arranged, the detection interface 12 and the vacuum gauge interface 13 are oppositely arranged on the outer wall of the piston sleeve 11 and are both perpendicular to the piston sleeve 11. One end of the vacuum gauge interface 13 away from the piston sleeve 11 is connected to a vacuum pressure gauge 33, and the vacuum pressure gauge 33 is communicated with the second end 112 of the piston sleeve 11 through the vacuum gauge interface 13.

[0029] Specifically, the inner diameter of the first end 111 is smaller than the inner diameter of the second end 112.

[0030] Further, a second piston 43 is also provided on the rod portion of the plunger rod 41. The second piston 43 is sealingly fitted in the inner cavity of the second end portion 112. After the first piston 42 is sealingly fitted with the first end portion 111, the spaces formed by the first piston 42, the second piston 43 and the piston sleeve 11 are respectively communicated with the vacuum gauge interface 13 and the detection interface 12.

[0031] Further, the inner diameter of the first end portion 111 is smaller than that of the second end portion 112. Two openings 113 are provided on the inner side wall of the second end portion 112. The two openings 113 are respectively communicated with the detection interface 12 and the vacuum gauge interface 13. After the first piston 42 is fitted with the first end portion 111, a part of the first piston 42 is located in the inner cavity of the second end portion 112. An annular cavity 15 is formed by the first piston 42, the second piston 43 and the inner side wall of the second end portion 112. The annular cavity 15 is respectively communicated with the detection interface 12 and the vacuum gauge interface 13 through the two openings 113. Preferably, the two openings 113 are arranged on the same radial section plane of the piston sleeve 11.

[0032] The outer diameter of the first piston 42 is smaller than that of the second piston 43. By applying a thrust or a pull force to the end of the plunger rod 41 away from the first piston 42, driven by the plunger rod 41, the second piston 43 and the first piston 42 perform reciprocating motions along the axial direction of the piston sleeve 11. The first piston 42 passes through the second end portion 112 and is sealingly connected to the first end portion 111. The two extreme positions of the second piston 43 moving along the axial direction of the piston sleeve 11 are both in the inner cavity of the second end portion 112. That is, when the plunger rod 41 moves, the second piston 43 is always sealingly fitted with the inner cavity of the second end portion 112. Moreover, the second piston 43 is always located between the opening 113 and the end face of the second end portion 112 away from the first end portion 111. That is, no matter where the second piston 43 moves to in the piston sleeve 11, the second piston 43 will not be located between the opening 113 and the first end portion 111.

[0033] Further, the two-way adapter 14 is provided with a sleeve joint and a vacuum joint. The sleeve joint is sealingly fitted with the first end portion 111. The first piston 42 is sealingly fitted with the sleeve joint. The vacuum joint extends out of the first end portion 111. The two-way adapter 14 is sealingly connected to the end of the first end portion 111. The first end portion 111 is communicated with the vacuum pumping device through the two-way adapter 14.

[0034] Preferably, the airtightness detection device further includes an air extraction pipeline 5, which is hermetically connected to the vacuum joint, and the two-way adapter 14 communicates with the vacuum extraction device through the air extraction pipeline 5. The two-way adapter 14 has a sleeve joint and a vacuum joint. The sleeve joint extends into the inner cavity of the first end portion 111; the vacuum joint extends out of the first end portion 111. Preferably, the sleeve joint is screwed to the first end portion 111, and the vacuum joint is screwed to the air extraction pipeline 5.

[0035] Optionally, a vacuum pressure gauge 3 is connected to the vacuum gauge interface 13, and the vacuum pressure gauge 3 is a mechanical vacuum pressure gauge 3 or a digital display vacuum pressure gauge 3.

[0036] Preferably, a first sealing ring 21 is provided on the first piston 42, a second sealing ring 44 is provided on the second piston 43, and a third sealing ring 45 is provided on the detection interface 12. In this way, the airtightness of the airtightness detection device itself is ensured, and errors are avoided from being introduced into the test results.

[0037] Preferably, the first piston 42 is screwed to the first end portion 111, and the second piston 43 is screwed to the second end portion 112. The end of the first piston 42 is provided with a first external thread, and the inner wall of the first end portion 111 is provided with a first internal thread that matches the first external thread. The first piston 42 is screwed into the inner cavity of the first end portion 111; the outer wall of the second piston 43 is provided with a second external thread, and the inner wall of the second end portion 112 is provided with a second internal thread that matches the second external thread. The second piston 43 is screwed into the inner cavity of the second end portion 112.

[0038] Specifically, the plunger rod 41 has a gripping end 46 away from the first piston 42, and the gripping end 46 is located outside the second end portion 112. Preferably, the outer diameter of the gripping end 46 is greater than the inner diameter of the piston sleeve 11.

[0039] Preferably, a limit snap ring 47 is further provided on the plunger rod 41, and the limit snap ring 47 is arranged between the holding end 46 and the second piston 43; a positioning clip 48 is provided on the inner wall of the piston sleeve 11. When the first piston 42 is away from the first end 111, the positioning clip 48 can abut against the second piston 43. When the first piston 42 is in sealing fit with the first end 111, the positioning clip 48 abuts against the limit snap ring 47. The limit snap ring 47, the second piston 43 and the plunger rod 41 therebetween form an I-shaped structure, and the positioning clip 48 is located in the concave structure of the I-shape. In this way, the two extreme positions of the movement of the second piston 43 in the piston sleeve 11 can be positioned, avoiding damage to the instrument due to excessive applied tensile force, or too small applied thrust force, resulting in incomplete sealing fit between the first piston 42 and the first end 111.

[0040] Preferably, the positioning clip 48 is an elastic clip, and the elastic clip can expand and contract along the radial direction of the piston sleeve 11. In one embodiment, one side of the second piston 43 facing the first end 111 has a first guiding inclined surface, and one side of the second piston 43 facing the limit snap ring 47 has a second guiding inclined surface. After the elastic clip is compressed by the first guiding inclined surface, the second piston 43 can enter between the elastic clip and the first end 111; after the elastic clip is compressed by the second guiding inclined surface, the second piston 43 can move and withdraw from the piston sleeve 11. In this way, it is ensured that the plunger 44 is detachably connected to the piston sleeve 11, and the second sealing ring 44 and the third sealing ring 45 can be replaced in time.

[0041] Preferably, a pressure relief port is provided on the air extraction pipeline 5.

[0042] On the basis of the above specific embodiments, the usage method of the airtightness detection device includes the steps:

[0043] S1. Sealingly connect the detection interface 12 of the airtightness detection device to the non-magnetic tube of the measurement-while-drilling device 2, and sealingly connect the vacuum extraction device to the two-way adapter 14.

[0044] S2. Apply a tensile force to the plunger 4 to move the first piston 42 away from the first end 111, turn on the vacuum extraction device to extract air, and record the first reading of the vacuum pressure gauge 3.

[0045] S3. Apply a thrust force to the plunger 4 to make the first piston 42 in sealing fit with the inner cavity of the first end 111, record the second reading of the vacuum pressure gauge 3 after exceeding the set time, and judge whether the airtightness of the device to be measured is qualified based on the first reading and the second reading.

[0046] Among them, it is determined whether the airtightness of the LWD tool is qualified based on the first detection value and the second detection value. Specifically, if the second detection value is less than or equal to the first detection value, the airtightness of the LWD tool is qualified; if the second detection value is greater than the first detection value, but the difference between the second detection value and the first detection value is less than or equal to the detection error threshold, the airtightness of the LWD tool is qualified; if the second detection value is greater than the first detection value, but the difference between the second detection value and the first detection value is greater than the detection error threshold, the airtightness of the LWD tool is unqualified.

[0047] Compared with the traditional airtightness detection device, the present invention reduces components such as valve switches, avoids air leakage at the valve switch, and improves the reliability and accuracy of the airtightness detection. In addition, the present invention has a simple and compact structure, a small volume, is easy to install and process, effectively reduces the manufacturing cost and improves the work efficiency.

[0048] The above description has fully disclosed the specific implementation manners of the present invention. It should be noted that any modifications made by those skilled in the art to the specific implementation manners of the present invention do not depart from the scope of the claims of the present invention. Correspondingly, the scope of the claims of the present invention is not limited to the foregoing specific implementation manners.

Claims

1. An airtightness detection device for a measurement-while-drilling instrument, characterized in that, it includes: A base (1), including a piston sleeve (11), and a vacuum gauge interface (13) and a detection interface (12) provided on the side wall of the piston sleeve (11). The vacuum gauge interface (13), the detection interface (12) and the inner cavity of the piston sleeve (11) are communicated. The piston sleeve (11) includes a first end (111) and a second end (112) that are communicated; A two-way adapter (14) for connecting a vacuum pumping device, provided at the first end (111). The vacuum pumping device is communicated with the inner cavity of the piston sleeve (11) through the two-way adapter (14), and thus is communicated with the vacuum gauge interface (13) and the detection interface (12); A plunger (4), including a plunger rod (41) and a first piston (42) provided at the end of the plunger rod (41). The first piston (42) extends into the inner cavity of the second end (112). Driven by the plunger rod (41), the first piston (42) can move away from or close to the first end (111). The first piston (42) can be in sealing cooperation with the first end (111) to disconnect the communication between the vacuum pumping device and the inner cavity of the piston sleeve (11); A vacuum pressure gauge (3) is connected to the vacuum gauge interface (13). One end of the vacuum gauge interface (13) far from the piston sleeve (11) is connected to the vacuum pressure gauge (3). The vacuum pressure gauge (3) is communicated with the second end (112) of the piston sleeve (11) through the vacuum gauge interface (13); A second piston (43) is further provided on the rod part of the plunger rod (41). The second piston (43) is in sealing cooperation in the inner cavity of the second end (112). After the first piston (42) is in sealing cooperation with the first end (111), the spaces formed by the first piston (42), the second piston (43) and the piston sleeve (11) are respectively communicated with the vacuum gauge interface (13) and the detection interface (12); Two openings (113) are provided on the inner side wall of the second end (112). The two openings (113) are respectively communicated with the detection interface (12) and the vacuum gauge interface (13). After the first piston (42) cooperates with the first end (111), part of the first piston (42) is located in the inner cavity of the second end (112). An annular cavity (15) is formed by the first piston (42), the second piston (43) and the inner side wall of the second end (112). The annular cavity (15) is respectively communicated with the detection interface (12) and the vacuum gauge interface (13) through the two openings (113).

2. The device according to claim 1, characterized in that, the inner diameter of the first end (111) is smaller than the inner diameter of the second end (112).

3. The device according to claim 1, characterized in that, The two-way adapter tube (14) is provided with a sleeve joint and a vacuum joint. The sleeve joint is sealingly fitted with the first end portion (111), the first piston (42) is sealingly fitted with the sleeve joint, and the vacuum joint extends out of the first end portion (111).

4. The device according to claim 3, wherein, it further comprises an air extraction pipeline (5). The air extraction pipeline (5) is sealingly connected to the vacuum joint, and the two-way adapter tube (14) is communicated with the vacuum extraction device through the air extraction pipeline (5).

5. The device according to claim 1, wherein, the vacuum pressure gauge (3) is a mechanical vacuum pressure gauge (3) or a digital display vacuum pressure gauge (3).

6. The device according to claim 1, wherein, a first sealing ring (21) is provided on the first piston (42), a second sealing ring (44) is provided on the second piston (43), and a third sealing ring (45) is provided on the detection interface (12).

7. The device according to claim 1, wherein, the first piston (42) is screwed to the first end portion (111), and the second piston (43) is screwed to the second end portion (112).

8. The device according to any one of claims 1-7, wherein, the usage method of the airtightness detection device comprises the steps of: S1. Sealingly connecting the detection interface (12) of the airtightness detection device to the non-magnetic tube of the measurement-while-drilling device (2), and sealingly connecting the vacuum extraction device to the two-way adapter tube (14); S2. Applying a pulling force on the plunger (4) to move the first piston (42) away from the first end portion (111), starting the vacuum extraction device to extract air, and recording the first indication value of the vacuum pressure gauge (3); S3. Applying a pushing force on the plunger (4) to make the first piston (42) sealingly fit with the inner cavity of the first end portion (111), recording the second indication value of the vacuum pressure gauge (3) after exceeding the set time, and judging whether the airtightness of the device to be measured is qualified based on the first indication value and the second indication value.

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