Insulating nipple for well logging

Abstract

The invention provides an insulating pup joint for logging, which relates to the technical field of logging instruments and comprises an upper joint main body, a lower joint main body and an insulator with two ends respectively sleeved with the upper joint main body and the lower joint main body. The upper connector body is sleeved with an insulating sleeve, and the lower connector body is connected with the upper connector body in a sleeved mode through the insulating sleeve. The insulating sleeve and an inner hole of the insulator are coaxially arranged, a pressure-bearing sealing block and a pressure-bearing ring are further arranged between the insulating sleeve and the insulator, and the pressure-bearing sealing block and the pressure-bearing ring are sequentially arranged on the outer side of the insulating sleeve in a sleeving mode in the axial direction of the upper connector body. Based on the technical scheme of the invention, while the insulation sealing performance and the structural reliability are ensured, the detachable function is realized, the later maintenance of the insulation short section is facilitated, the service life of the insulation short section can be prolonged, and the reduction of resource waste is facilitated.

Description

Technical Field

[0001] The invention relates to the technical field of well logging instruments, in particular to an insulating nipple for well logging. Background Art

[0002] The insulating nipple is one of the necessary supporting equipment for many logging instruments during the logging process. It is a must-have in many steering logging instruments such as dual lateral logging instruments, micro resistivity logging instruments and formation dip logging instruments. It is also an indispensable supporting equipment in comprehensive testing platforms with integrated performance such as string logging. The function of the insulating nipple is to directly connect to the upper part of the logging instrument through its upper joint or to the lower part of the logging instrument through its lower joint during logging, so that the casing of the logging instrument is well insulated from the casing of other instruments connected to the upper or lower part, meeting the test requirements, so as to ensure the smooth completion of the logging process of the logging instrument.

[0003] With the continuous development of logging instruments, miniaturization and continuous improvement of performance indicators have become an inevitable development trend in the logging industry. The development trend of small-diameter, high-index logging instruments in production logging, through-hole logging, through-casing logging and horizontal well logging environments requires that the supporting equipment of small-diameter, high-index logging instruments must have reliable performance indicators.

[0004] At present, the insulating nipples in existing logging instruments, especially the insulating nipples in ultra-high temperature and ultra-high pressure logging environments, are all integrated and cannot be disassembled. If the insulating performance of the insulating nipples is poor, they cannot be repaired, resulting in a large waste of resources. Summary of the invention

[0005] The present invention provides an insulating nipple for well logging, which uses an insulator to connect an upper joint body and a lower joint body, and arranges a pressure-bearing sealing block and a pressure-bearing ring inside the insulator, so as to ensure the sealing and insulating performance of the connection between the upper joint body and the lower joint body and realize a detachable function, facilitate later maintenance, prolong the service life of the insulating nipple, and help reduce resource waste.

[0006] The present invention provides an insulating nipple for well logging, comprising an upper joint body, a lower joint body and an insulator whose two ends are respectively sleeved with the upper joint body and the lower joint body; an insulating sleeve is sleeved on the upper joint body, and the lower joint body is sleeved with the upper joint body through the insulating sleeve; the insulating sleeve is coaxially arranged with an inner hole of the insulator, a pressure-bearing sealing block and a pressure-bearing ring are further arranged between the insulating sleeve and the insulator, and the pressure-bearing sealing block and the pressure-bearing ring are sequentially sleeved on the outer side of the insulating sleeve along the axial direction of the upper joint body.

[0007] In one embodiment, the pressure-bearing sealing block abuts against a shoulder on the outer wall of the upper joint body, and the receiving sealing block abuts against the end of the lower joint body through the pressure-bearing ring. Through this embodiment, the pressure-bearing sealing block can play a pressure-bearing sealing role, and the pressure-bearing ring also has a pressure-bearing role in a high temperature environment due to its high strength.

[0008] In one embodiment, sealing rings are provided at each contact surface between the pressure-bearing sealing block and the outer wall of the upper joint body, the outer wall of the insulating sleeve and the inner wall of the insulator. Through this embodiment, multiple sealing rings can achieve insulation and sealing for each contact surface between the pressure-bearing sealing block and other components.

[0009] In one embodiment, the pressure-bearing sealing block is made of high-strength metal material, and the pressure-bearing ring is made of high-temperature sintered ceramic.

[0010] In one embodiment, the lower joint body is provided with an inner hole on the side away from the upper joint body, and an anti-rotation ring is embedded in the inner hole and is sleeved with the upper joint body. The anti-rotation ring is connected to the inner wall of the lower joint body through an anti-rotation pin, and is keyed to the outer wall of the upper joint body through an anti-rotation key. Through this embodiment, the anti-rotation ring cooperates with the anti-rotation pin and the anti-rotation key to achieve circumferential positioning of the upper joint body and the lower joint body to prevent the two from rotating relative to each other.

[0011] In one embodiment, an insulating pad is embedded in the inner hole, the insulating pad is sleeved on the upper connector body, and the anti-rotation ring abuts against the bottom of the inner hole through the insulating pad. Through this embodiment, the insulating pad can play an insulating and sealing role between the anti-rotation ring and the lower connector body.

[0012] In one embodiment, the anti-rotation ring is provided with a positioning hole for inserting the anti-rotation pin; the head of the anti-rotation pin is embedded in the positioning hole, and the head of the anti-rotation pin is covered with an insulating cap, and the head of the anti-rotation pin abuts against the inner wall of the positioning hole through the insulating cap. Through this embodiment, the insulating cap can achieve insulation sealing between the anti-rotation ring and the anti-rotation pin.

[0013] In one embodiment, a tensioning nut and an anti-rotation back cap are sequentially arranged on one side of the anti-rotation ring away from the bottom of the inner hole, and the tensioning nut and the anti-rotation back cap are both threadedly connected to the core shaft portion of the upper joint body. Through this embodiment, the tensioning nut cooperates with the anti-rotation back cap to play an axial positioning role for the anti-rotation ring.

[0014] In one embodiment, a grease injection hole is provided inside the lower joint body, one end of the grease injection hole extends to the connection part between the upper joint body and the lower joint body, and the other end penetrates the outer wall of the lower joint body, and a grease injection screw is provided in the inner thread of one end of the grease injection hole penetrating the outer wall of the lower joint body. According to this embodiment, high-temperature silicone grease can be filled into the connection part between the upper joint body and the lower joint body by means of the grease injection hole to improve the insulation sealing performance between the two, and the grease injection screw can seal the grease injection hole to prevent external mud from entering the interior of the insulating short joint through the grease injection hole.

[0015] In one embodiment, the insulator is made of PEEK wear-resistant insulating material.

[0016] In summary, compared with the prior art, the beneficial technical effects of the present invention are:

[0017] (1) The upper joint body and the lower joint body are connected by an insulator, and the pressure-bearing sealing block and the pressure-bearing ring arranged inside the insulator are matched to ensure the insulation and sealing performance of the connection between the upper joint body and the lower joint body, and realize the detachable function of the insulating short joint, which is convenient for the later maintenance of the insulating short joint, can extend the service life of the insulating short joint, and help reduce resource waste;

[0018] (2) With the help of anti-rotation ring, anti-rotation pin, anti-rotation key, tightening nut and anti-rotation back cap, the upper joint body and the lower joint body are circumferentially positioned to prevent relative rotation between the upper joint body and the lower joint body, thereby improving the stability and reliability of the insulating short section structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The present invention will be described in more detail below based on embodiments and with reference to the accompanying drawings, wherein:

[0020] Figure 1 It is a schematic diagram of the overall structure of an insulating short section in one embodiment of the present invention;

[0021] Figure 2 It is a structural schematic diagram of the connection portion between the upper joint body and the lower joint body in one embodiment of the present invention;

[0022] Figure 3 It is a schematic diagram of the structure of an anti-rotation ring in one embodiment of the present invention.

[0023] Figure numerals: 1. upper connector body; 2. insulator; 3. pressure-bearing sealing block; 4. pressure-bearing ring; 5. insulating sleeve; 6. lower connector body; 7. insulating pad; 8. anti-rotation ring; 81. positioning hole; 9. anti-rotation pin; 10. insulating cap; 11. anti-rotation key; 12. tightening nut; 13. anti-rotation back cap; 14. lower connector; 15. grease injection hole; 16. grease injection screw; 17. sealing ring. DETAILED DESCRIPTION

[0024] The present invention will be described clearly and completely below with reference to the accompanying drawings.

[0025] See attached Figure 1-2 , an insulating nipple for logging, comprising an upper joint body 1, a lower joint body 6 connected to the upper joint body 1, and a lower connector 14 connected to the lower joint body 6. The core shaft of the upper joint body 1 is inserted into the lower joint body 6, and the two are coaxially arranged to form a stable sleeve connection; the lower joint body 6 is provided with an inner hole on the side away from the upper joint body 1, and the end of the lower connector 14 is threadedly connected to the end of the inner hole, so as to achieve a stable connection between the lower joint body 6 and the lower connector 14. To ensure the sealing effect, a sealing ring 17 is provided at the connection between the lower joint body 6 and the lower connector 14, and the sealing ring 17 can be an O-type sealing ring 17.

[0026] In order to connect the upper joint body 1 and the lower joint body 6, an insulator 2 is sleeved on the upper joint body 1, and one end of the insulator 2 away from the upper joint body 1 is sleeved and connected with the adjacent end of the lower joint body 6. In order to ensure the insulation and sealing effect, a sealing ring 17 is provided at the connection between the insulator 2 and the upper joint body 1 and the lower joint body 6, and the sealing ring 17 can also be an O-type sealing ring 17.

[0027] In this embodiment, in order to facilitate the connection between the upper joint body 1 and the lower joint body 6, the insulator 2 can be set as a hollow sleeve structure, and its two ends are respectively sleeved with the upper joint body 1 and the lower joint body 6, and the three are preferably coaxially arranged. At the same time, in order to ensure the insulation and sealing performance of the insulating short section, the insulator 2 can be made of PEEK wear-resistant insulating material, or other materials with wear-resistant and insulating effects, which are not specifically limited.

[0028] See attached Figure 2 After the insulator 2 is sleeve-connected with the upper joint body 1 and the lower joint body 6, in order to further improve the insulation sealing effect at the connection between the upper joint body 1 and the lower joint body 6, an insulation sealing structure is also provided at the connection between the two.

[0029] In this embodiment, the insulating sealing structure includes an insulating sleeve 5 sleeved on the core shaft of the upper joint body 1. The insulating sleeve 5 can be made of rubber or other insulating materials, which is not specifically limited. The insulating sleeve 5 is sleeved on the core shaft of the upper joint body 1, and the end of the lower joint body 6 close to the upper joint body 1 is sleeved with the core shaft of the upper joint body 1 through the insulating sleeve 5. Among them, a sealing ring 17 can also be set between the insulating sleeve 5 and the lower joint body 6 for sealing.

[0030] In another embodiment, the insulating sealing structure further comprises a pressure-bearing sealing block 3 and a pressure-bearing ring 4 sleeved on the outside of the insulating sleeve 5, and the pressure-bearing sealing block 3 and the pressure-bearing ring 4 are sequentially embedded in the inner hole of the insulator 2 along the axial direction of the upper joint body 1. Among them, the pressure-bearing sealing block 3 is preferably sleeved on the shoulder of the upper joint body 1 close to its core shaft, and the pressure-bearing ring 4 is arranged on the side of the pressure-bearing sealing block 3 away from the shoulder of the upper joint body 1, and the side of the pressure-bearing ring 4 away from the pressure-bearing sealing block 3 abuts against the adjacent end of the lower joint body 6.

[0031] In order to ensure the insulating sealing effect, the pressure ring 4 can be made of insulating material, and considering the pressure bearing problem, it is preferably made of high-temperature sintered ceramics, because high-position sintered ceramics have high strength, so the pressure ring 4 also has a pressure bearing function at high temperature. At the same time, since the pressure-bearing sealing block 3 is arranged at the shoulder position of the upper joint body 1, in order to ensure the sealing effect, a sealing ring 17 should be arranged between the pressure-bearing sealing block 3 and the inner wall of the insulator 2, the outer wall of the upper joint body 1 and the outer wall of the insulating sleeve 5 for sealing treatment, and the corresponding sealing ring 17 can be an O-ring 17. The material of the pressure-bearing sealing block 3 is preferably a high-strength metal material, such as a nickel-based alloy, to ensure the pressure-bearing performance at the insulator 2, and its specific material is not limited.

[0032] See attached Figure 2-3 The insulator 2 is used to connect the upper joint body 1 and the lower joint body 6, so that the insulating short section can be detachable. At this time, in order to ensure the reliability of the connection structure between the upper joint body 1 and the lower joint body 6, an anti-rotation structure is also provided in the inner hole of the lower joint body 6 away from the upper joint body 1, and the anti-rotation structure can realize the axial and axial positioning of the upper joint body 1 and the lower joint body 6.

[0033] Specifically, the anti-rotation structure includes an anti-rotation ring 8 embedded in the inner hole of the lower joint body 6. The anti-rotation ring 8 is sleeved on the core shaft of the upper joint body 1 and is coaxially arranged with the inner hole of the lower joint body 6. A positioning hole 81 is opened on the anti-rotation ring 8 along the axial direction of the lower joint body 6. The positioning holes 81 can be set 1, 2, 3 or 4, and the specific number is not limited; but when multiple positioning holes 81 are set, each positioning hole 81 is preferably evenly spaced on the anti-rotation ring 8 along its circumferential direction.

[0034] Taking any one of the positioning holes 81 as an example, an anti-rotation pin 9 is passed through the positioning hole 81, and the end of the anti-rotation pin 9 away from the positioning hole 81 is inserted into the pin hole on the bottom surface of the inner hole of the lower joint body 6, that is, the anti-rotation ring 8 is pin-connected with the lower joint body 6 through the anti-rotation pin 9.

[0035] Meanwhile, a keyway is provided on the inner wall of the anti-rotation ring 8, and an anti-rotation key 11 is embedded in the keyway, so the anti-rotation ring 8 can cooperate with the keyway on the core shaft of the upper joint body 1 through the anti-rotation key 11 to achieve key connection.

[0036] In this way, the anti-rotation ring 8 is connected to the lower joint body 6 through the anti-rotation pin 9 on the one hand, and is connected to the core shaft key of the upper joint body 1 through the anti-rotation key 11 on the other hand, which can prevent the upper joint body 1 and the lower joint body 6 from rotating relative to each other, thereby achieving circumferential positioning of the upper joint body 1 and the lower joint body 6.

[0037] In addition, the anti-rotation structure also includes a tensioning nut 12 and an anti-rotation back cap 13 arranged on the side of the anti-rotation ring 8 away from the bottom surface of the inner hole of the lower joint body 6. The tensioning nut 12 and the anti-rotation back cap 13 are sequentially sleeved on the core shaft of the upper joint body 1 along the axial direction of the upper joint body 1, and are threadedly connected with the core shaft of the upper joint body 1. When the tensioning nut 12 and the anti-rotation back cap 13 are tightened, the tensioning nut 12 abuts against the anti-rotation ring 8, thereby abutting the anti-rotation ring 8 against the bottom surface of the inner hole of the lower joint body 6, which effectively limits the axial runout of the anti-rotation ring 8 on the one hand, and also realizes the axial positioning of the upper joint body 1 and the lower joint body 6 on the other hand.

[0038] In another embodiment, in order to further ensure the insulation and sealing effect at the connection between the upper joint body 1 and the lower joint body 6, an insulating pad 7 is further embedded in the inner hole of the lower joint body 6, and the insulating pad 7 is sleeved on the core shaft of the upper joint body 1 and is located on the side of the anti-rotation ring 8 away from the tightening nut 12. When the tightening nut 12 and the anti-rotation back cap 13 are tightened, the anti-rotation ring 8 is pressed against the bottom surface of the inner hole of the lower joint body 6 through the insulating pad 7.

[0039] At the same time, the head of the anti-rotation pin 9 (that is, the end of the anti-rotation pin 9 away from the corresponding pin hole) is also sleeved with an insulating cap 10, and the head of the anti-rotation pin 9 is abutted against the inner wall of the corresponding positioning hole 81 through the insulating cap 10. The insulating cap 10 can achieve insulation between the anti-rotation pin 9 and the anti-rotation ring 8.

[0040] It should be noted that, in order to ensure the reliability of the connection between the upper joint body 1 and the lower joint body 6, the tightening nut 12 and the anti-rotation cap 13 are preferably made of high-strength metal material, such as nickel-based alloy, and the specific material is not limited.

[0041] See attached Figure 2 A grease injection hole 15 is provided inside the lower joint body 6, one end of the grease injection hole 15 extends to the joint tail of the upper joint body 1 and the lower joint body 6, and the other end penetrates the outer wall of the lower joint body 6. In practical applications, the staff can fill the connection part of the upper joint body 1 and the lower joint body 6 with high-temperature silicone grease through the grease injection hole 15 to improve its insulation and sealing effect.

[0042] Specifically, one end of the grease injection hole 15 can extend to the position of the pressure ring 4 , and the other end thereof can penetrate the outer wall of the lower joint body 6 in a radial direction perpendicular to the lower joint body 6 .

[0043] At the same time, in order to ensure the sealing effect, a grease injection hole 15 is passed through one end of the lower joint body 6 and a grease injection screw 16 is arranged inside. The grease injection screw 16 is threadedly connected to the grease injection hole 15, which can effectively seal the grease injection hole 15 and prevent external mud from entering the insulating short section through the grease injection hole 15.

[0044] In the description of the present invention, it should be understood that terms such as “upper”, “lower”, “bottom”, “top”, “front”, “back”, “inside”, “outside”, “left” and “right” indicating directions or positional relationships are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as limiting the present invention.

[0045] Although the present invention has been described with reference to preferred embodiments, various modifications may be made thereto and parts thereof may be replaced by equivalents without departing from the scope of the present invention. In particular, the various technical features mentioned in the various embodiments may be combined in any manner as long as there are no structural conflicts. The present invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. An insulating short joint for well logging, characterized in that: It includes an upper joint body, a lower joint body and an insulator whose two ends are respectively sleeved with the upper joint body and the lower joint body; an insulating sleeve is sleeved on the upper joint body, and the lower joint body is sleeved with the upper joint body through the insulating sleeve; the insulating sleeve is coaxially arranged with the inner hole of the insulator, and a pressure-bearing sealing block and a pressure-bearing ring are also arranged between the insulating sleeve and the insulator, and the pressure-bearing sealing block and the pressure-bearing ring are sequentially sleeved on the outer side of the insulating sleeve along the axial direction of the upper joint body.

2. The insulating sub for well logging according to claim 1, characterized in that: The pressure-bearing sealing block abuts against a shaft shoulder on the outer wall of the upper joint body, and the receiving sealing block abuts against the end of the lower joint body through the pressure-bearing ring.

3. The insulating sub for well logging according to claim 1, characterized in that: Sealing rings are provided at each contact surface between the pressure-bearing sealing block and the outer wall of the upper joint body, the outer wall of the insulating sleeve and the inner wall of the insulator.

4. An insulating sub for well logging according to any one of claims 1 to 3, characterized in that: The pressure-bearing sealing block is made of high-strength metal material, and the pressure-bearing ring is made of high-temperature sintered ceramics.

5. The insulating sub for well logging according to claim 1, characterized in that: The lower joint body is provided with an inner hole on one side away from the upper joint body, an anti-rotation ring which is sleeved with the upper joint body is embedded in the inner hole, the anti-rotation ring is connected to the inner wall of the lower joint body through an anti-rotation pin, and is keyed to the outer wall of the upper joint body through an anti-rotation key.

6. The insulating sub for well logging according to claim 5, characterized in that: An insulating pad is also embedded in the inner hole, and the insulating pad is sleeved on the upper joint body, and the anti-rotation ring abuts against the bottom of the inner hole through the insulating pad.

7. The insulating sub for well logging according to claim 5, characterized in that: The anti-rotation ring is provided with a positioning hole for inserting the anti-rotation pin; the head of the anti-rotation pin is embedded in the positioning hole, and the head of the anti-rotation pin is covered with an insulating cap, and the head of the anti-rotation pin abuts against the inner wall of the positioning hole through the insulating cap.

8. An insulating sub for well logging according to any one of claims 5 to 7, characterized in that: A tensioning nut and an anti-rotation back cap are sequentially arranged on one side of the anti-rotation ring away from the bottom of the inner hole, and both the tensioning nut and the anti-rotation back cap are threadedly connected to the core shaft portion of the upper joint body.

9. An insulating sub for well logging according to any one of claims 1 to 3, characterized in that: A grease injection hole is arranged inside the lower joint body, one end of the grease injection hole extends to the connection position between the upper joint body and the lower joint body, and the other end passes through the outer wall of the lower joint body, and a grease injection screw is arranged on the internal thread of one end of the grease injection hole passing through the outer wall of the lower joint body.

10. An insulating sub for well logging according to any one of claims 1 to 3, characterized in that: The insulator is made of PEEK wear-resistant insulating material.

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