Well logging exploring tube centralizer
By designing a combination of lantern-shaped stabilizers and fixing rings, the problem of obstructed descent of the probe caused by the borehole diameter change platform was solved, ensuring that the logging instruments could pass smoothly through the diameter change platform and achieving continuity of logging work.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- 129 EXPLORATION TEAM GENERAL ADMINISTRATION OF CHINA COAL GEOLOGY
- Filing Date
- 2025-02-24
- Publication Date
- 2026-04-28
AI Technical Summary
During the logging process, the borehole diameter reduction platform caused obstruction to the lowering of the probe, affecting the smooth progress of the logging work.
Design a logging probe centralizer, including a fixing ring and a centralizer. The fixing ring is fixedly connected to the probe, and the centralizer is slidably connected to the probe. The outer surface of the centralizer is lantern-shaped, and its maximum diameter is larger than the diameter of the borehole below the diameter change position but smaller than the diameter of the borehole above it, so as to avoid obstruction of the probe's downward movement.
The lantern-shaped stabilizer design allows the probe to pass smoothly through the borehole diameter reduction platform, ensuring that the logging instruments can be lowered and raised smoothly, avoiding obstruction during the probe's descent, and achieving continuity of logging operations.
Smart Images
Figure CN224174036U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of drilling technology, and in particular relates to a logging pipe straightener. Background Technology
[0002] In well logging, the object of logging is the borehole. Boreholes with a slightly larger diameter or deep wells are often divided into one, two, or three sections. The diameter of the borehole will decrease from top to bottom. At the point of diameter change, a platform with a certain width will be formed. However, the downhole logging instruments in coalfields are often only tens of millimeters or even smaller. This will cause the probe to be blocked when encountering the platform of diameter change in the well, making it impossible to complete the logging work. Utility Model Content
[0003] In view of this, the present invention aims to provide a logging probe straightener to avoid the logging probe being obstructed by the platform at the borehole diameter change point during the logging probe's lowering process, thus affecting the logging work.
[0004] To achieve the above objectives, the technical solution of this utility model is implemented as follows:
[0005] A logging pipe straightener includes a fixing ring and a straightener component;
[0006] Both the fixing ring and the straightening member are sleeved on the outside of the probe. The fixing ring is fixedly connected to the probe, and the straightening member is slidably connected to the probe. The straightening member is located on the upper side of the fixing ring near the wellhead.
[0007] The outer diameter of the fixed ring is smaller than the minimum diameter of the well, and the inner diameter of the fixed ring corresponds to the outer diameter of the probe.
[0008] The minimum inner diameter of the stabilizer corresponds to the outer diameter of the probe. The outer surface of the stabilizer is lantern-shaped, rising from both ends to the middle along the axis of the stabilizer. The maximum diameter of the outer side of the stabilizer is greater than the diameter of the borehole below the diameter change position where the stabilizer stays in the well, and smaller than the diameter of the borehole above the diameter change position.
[0009] Optionally, the straightening component includes a raised component, a first connecting ring fixed to the upper end of the raised component, and a second connecting ring fixed to the lower end of the raised component;
[0010] The outer diameter of the raised member gradually increases from the connection point with the first connecting ring and the second connecting ring toward the middle.
[0011] Optionally, the raised member is formed by combining multiple arc-shaped raised pieces, with the upper end of each arc-shaped raised piece fixedly connected to the first connecting ring, the lower end of each arc-shaped raised piece fixedly connected to the second connecting ring, and the middle part of each arc-shaped raised piece protruding away from the axis of the straightening member.
[0012] Optionally, the straightening component includes a first part and a second part that are fastened and sleeved on the outside of the probe, wherein the first part and the second part are detachably connected.
[0013] Optionally, the first connecting ring includes a detachably connected first half-ring and a second half-ring, and the second connecting ring includes a detachably connected third half-ring and a fourth half-ring. The positions of the first half-ring and the third half-ring are vertically corresponding. The first half-ring and the third half-ring are connected by multiple arc-shaped raised pieces, and the second half-ring and the fourth half-ring are also connected by multiple arc-shaped raised pieces.
[0014] Optionally, a first protrusion is provided at the end of the first half-ring near the second half-ring. The vertical thickness of the first protrusion is less than the thickness of the first half-ring. A second protrusion is provided at the end of the second half-ring near the first half-ring to cooperate with the first protrusion. The first protrusion and the corresponding second protrusion are detachably connected.
[0015] The third half-ring has a third protrusion at its end near the fourth half-ring. The vertical thickness of the third protrusion is less than the thickness of the third half-ring. The fourth half-ring has a fourth protrusion at its end near the third half-ring, corresponding to the third protrusion. The third protrusion and the corresponding fourth protrusion are detachably connected.
[0016] Optionally, the first protrusion is disposed near the lower surface of the first half-ring, and the third protrusion is disposed near the upper surface of the third half-ring;
[0017] A first horizontal pin hole is provided between the upper surface of the first boss and the lower surface of the second boss, and the axis of the first horizontal pin hole is perpendicular to the axis of the straightening member.
[0018] A second horizontal pin hole is provided between the lower surface of the third boss and the upper surface of the fourth boss, and the axis of the second horizontal pin hole is perpendicular to the axis of the straightening member.
[0019] Optionally, the first boss and the corresponding second boss are provided with vertical first countersunk holes and are connected by first countersunk bolts; the third boss and the corresponding fourth boss are provided with vertical second countersunk holes and are connected by second countersunk bolts.
[0020] Optionally, the circumference of the fixing ring is provided with multiple countersunk threaded holes, the axis of the countersunk threaded holes is perpendicular to the axis of the fixing ring, and the circumference of the fixing ring is screwed to the corresponding countersunk threaded holes by multiple bolts and then abuts against the probe inside the fixing ring.
[0021] Optionally, the fixing ring includes a third part and a fourth part that are fastened to the outside of the probe, and the third part and the fourth part are detachably connected.
[0022] Compared with the prior art, the logging pipe centering device of this utility model has the following beneficial effects:
[0023] This application provides a logging probe centralizer, specifically including a fixing ring and a centralizer; both the fixing ring and the centralizer are sleeved on the outside of the probe, the fixing ring is fixedly connected to the probe, and the centralizer is slidably connected to the probe, the centralizer being disposed on the upper side of the fixing ring near the wellhead; the outer diameter of the fixing ring is smaller than the minimum diameter of the well, and the inner diameter of the fixing ring corresponds to the outer diameter of the probe; the minimum inner diameter of the centralizer corresponds to the outer diameter of the probe, the outer surface of the centralizer is lantern-shaped, bulging from both ends towards the middle along the centralizer's axial direction, and the maximum diameter of the outer side of the centralizer is larger than the diameter of the borehole below the diameter-changing position where the centralizer stops in the well, and smaller than the diameter of the borehole above the diameter-changing position. In this way, a fixing ring and a centralizer are fitted onto the logging probe. The centralizer is located on the side of the fixing ring near the wellhead. When the logging instrument is lowered, the maximum diameter of the outer side of the centralizer is greater than the diameter of the borehole below the diameter change position where the centralizer stops in the well, but smaller than the diameter of the borehole above the diameter change position. Therefore, from the wellhead of the well to the diameter change position where the centralizer stops, the probe is kept in the middle of the well due to the raised lantern-shaped structure, preventing the probe from being obstructed by the diameter change. Furthermore, the centralizer is slidably connected to the probe, so it will not affect the probe's continued downward movement for detection. When the probe is subsequently retracted, the fixing ring will move the centralizer upward. Attached Figure Description
[0024] The accompanying drawings, which form part of this utility model, are used to provide a further understanding of the utility model. The illustrative embodiments of the utility model and their descriptions are used to explain the utility model and do not constitute an undue limitation of the utility model. In the drawings:
[0025] Figure 1 This is a schematic diagram of the structure of a logging probe stabilizer in drilling, as described in an embodiment of this utility model.
[0026] Figure 2 This is a schematic diagram of the structure of a logging pipe stabilizer according to an embodiment of the present invention;
[0027] Figure 3 This is a schematic diagram illustrating the separation of the straightening component from the fixing ring according to an embodiment of this utility model.
[0028] Explanation of reference numerals in the attached figures:
[0029] 1-Fixing ring; 11-Third part; 12-Fourth part; 13-Counterhead threaded hole; 2-Straightening component; 21-Raised component; 211-Raised piece; 22-First connecting ring; 22-First half ring; 222-Second half ring; 223-First boss; 224-Second boss; 23-Second connecting ring; 231-Third half ring; 232-Fourth half ring; 233-Third boss; 234-Fourth boss; 24-First horizontal pin hole; 25-Second horizontal pin hole; 3-Probe; 4-Drilling well. Detailed Implementation
[0030] It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments of the present invention can be combined with each other.
[0031] In the description of this utility model, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more.
[0032] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.
[0033] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.
[0034] See Figure 1 The diagram shows the structure of a logging pipe stabilizer in drilling. A logging pipe stabilizer may include a fixing ring 1 and a stabilizer 2.
[0035] Both the fixing ring 1 and the straightening member 2 are sleeved on the outside of the probe 3. The fixing ring 1 is fixedly connected to the probe 3, and the straightening member 2 is slidably connected to the probe 3. The straightening member 2 is located on the upper side of the fixing ring 1 near the wellhead of the drilling 4. The outer diameter of the fixing ring 1 is smaller than the minimum diameter of the drilling 4, and the inner diameter of the fixing ring 1 corresponds to the outer diameter of the probe 3.
[0036] The minimum inner diameter of the stabilizer 2 corresponds to the outer diameter of the probe 3. The outer surface of the stabilizer 2 is lantern-shaped, rising from both ends to the middle along the axis of the stabilizer 2. The maximum diameter of the outer side of the stabilizer 2 is greater than the diameter of the borehole below the diameter change position where the stabilizer 2 stays in the drilling 4, and smaller than the diameter of the borehole above the diameter change position.
[0037] The probe tube 3 is lowered into the well 4 to assist the logging tool in detecting information such as the size of the well 4. The large-diameter well 4 will have a diameter change in the middle from top to bottom, and a platform will be formed at the diameter change position. During the lowering of the probe tube 3, this platform may cause the lowering of the probe tube 3 to be obstructed, affecting the logging work. Therefore, this application adopts a lantern-shaped stabilizer 2 with a raised circumference in the middle. Since the maximum diameter of the stabilizer 2 is larger than the diameter of the borehole below the diameter change position where the stabilizer 2 stops in the well 4, but smaller than the diameter of the borehole above the diameter change position, the probe tube 3 avoids the platform during the lowering process.
[0038] For example, commonly used drilling bit specifications for well 4 have diameters of 94 mm, 165 mm, 215 mm, and 311 mm. If the borehole diameters of the well to be tested are set from top to bottom to be 311 mm, 215 mm, 165 mm, and 94 mm respectively, see [reference needed]. Figure 1 The fixing ring 1 has an inner diameter of 56 mm and is made of stainless steel with a wall thickness of 5 mm. Three centralizing elements 2 can be sequentially installed on the probe 3 from the upper surface of the fixing ring 1 to the wellhead. These are designated as centralizing element 2-1, centralizing element 2-2, and centralizing element 2-3. The diameter change point of centralizing element 2-1 is from 165 mm to 94 mm, so the maximum outer diameter of centralizing element 2-1 can be 150 mm. The diameter change point of centralizing element 2-2 is from 215 mm to 165 mm, so the maximum outer diameter of centralizing element 2-2 can be 190 mm. The diameter change point of centralizing element 2-3 is from 311 mm to 215 mm, so the maximum outer diameter of centralizing element 2-3 can be 290 mm. The three centralizing elements 2 are slidably connected to the probe 3.
[0039] It should be noted that the difference between the maximum diameter of the straightening member 2 and the outer diameter of the end of the straightening member 2 is greater than the difference between the diameter of the borehole above the diameter change position and the diameter of the borehole below the diameter change position (or the maximum width of the platform at the diameter change position).
[0040] In one possible implementation, see Figure 2 The diagram shows a structural schematic of a logging pipe stabilizer. The stabilizer 2 includes a raised part 21, a first connecting ring 22 fixed to the upper end of the raised part 21, and a second connecting ring 23 fixed to the lower end of the raised part 21. The outer diameter of the raised part 21 gradually increases from the connection point with the first connecting ring 22 and the second connecting ring 23 towards the middle.
[0041] The outer diameters of the first connecting ring 22 and the second connecting ring 23 can both correspond to the outer diameter of the fixed ring 1. The inner diameters of the first connecting ring 22 and the second connecting ring 23 can be the same. The inner diameters of the first connecting ring 22 and the second connecting ring 23 are greater than the outer diameter of the probe 3.
[0042] Furthermore, the raised member 21 is formed by combining multiple arc-shaped raised pieces 211. The upper end of each arc-shaped raised piece 211 is fixedly connected to the first connecting ring 22, and the lower end of the arc-shaped raised piece 211 is fixedly connected to the second connecting ring 23. The middle part of the arc-shaped raised piece 211 protrudes away from the axis of the straightening member 2.
[0043] The raised part 21 is formed by multiple arc-shaped raised pieces 211 surrounding it, and there is a gap between two adjacent raised pieces to save costs.
[0044] In one possible implementation, the straightening member 2 includes a first part and a second part that are fastened to the outside of the probe 3, wherein the first part and the second part are detachably connected.
[0045] The straightening component 2 includes a first part and a second part that are fastened to the outside of the probe tube 3. This means that after the first part and the second part are fastened together, they can be installed on the probe tube 3, making it convenient to remove and install from the probe tube 3.
[0046] Furthermore, in a first possible implementation, the first connecting ring 22 includes a detachably connected first half-ring 221 and a second half-ring 222, and the second connecting ring 23 includes a detachably connected third half-ring 231 and a fourth half-ring 232. The positions of the first half-ring 221 and the third half-ring 231 are vertically aligned. The first half-ring 221 and the third half-ring 231 are connected by a plurality of arc-shaped raised pieces 211, and the second half-ring 222 and the fourth half-ring 232 are also connected by a plurality of arc-shaped raised pieces 211.
[0047] Specifically, the first half-ring 221 and the third half-ring 231 are vertically aligned and connected by multiple arc-shaped raised pieces 211 to form the first part. Similarly, the second half-ring 222 and the fourth half-ring 232 are also connected by multiple arc-shaped raised pieces 211 to form the second part. The first part and the second part are detachably connected.
[0048] Optionally, a first protrusion 223 is provided at the end of the first half-ring 221 near the second half-ring 222. The vertical thickness of the first protrusion 223 is less than the thickness of the first half-ring 221. A second protrusion 224 is provided at the end of the second half-ring 222 near the first half-ring 221 in cooperation with the first protrusion 223. The first protrusion 223 and the corresponding second protrusion 224 are detachably connected.
[0049] The third half-ring 231 is provided with a third protrusion 233 at the end near the fourth half-ring 232. The vertical thickness of the third protrusion 233 is less than the thickness of the third half-ring 231. The fourth half-ring 232 is provided with a fourth protrusion 234 at the end near the third half-ring 231, corresponding to the third protrusion 233. The third protrusion 233 and the corresponding fourth protrusion 234 are detachably connected.
[0050] Optionally, the first boss 223 is disposed near the lower surface of the first semi-ring 221, and the third boss 233 is disposed near the upper surface of the third semi-ring 231; a first horizontal pin hole 24 is provided between the upper surface of the first boss 223 and the lower surface of the second boss 224, and the axis of the first horizontal pin hole 24 is perpendicular to the axis of the straightening member 2; a second horizontal pin hole 25 is provided between the lower surface of the third boss 233 and the upper surface of the fourth boss 234, and the axis of the second horizontal pin hole 25 is perpendicular to the axis of the straightening member 2.
[0051] Specifically, the first boss 223 of the first half-ring 221 and the third boss 233 of the third half-ring 231 of the first part are respectively set on the outside of the second boss 224 of the second half-ring 222 and the fourth boss 234 of the fourth half-ring 232 of the second part. After the first part and the second part are fastened to the outside of the probe 3, pins are provided in both the first horizontal pin hole 24 and the second pin hole. Since the first horizontal pin hole 24 and the second pin hole are both perpendicular to the axis of the straightener 2, the connection between the first part and the second part is realized, which is convenient to operate.
[0052] In a second possible implementation, the first boss 223 and the corresponding second boss 224 are provided with vertical first countersunk holes and are connected by first countersunk bolts; the third boss 233 and the corresponding fourth boss 234 are provided with vertical second countersunk holes and are connected by second countersunk bolts.
[0053] In one possible implementation, the fixing ring 1 is provided with a plurality of countersunk threaded holes 13 around its circumference. The axis of the countersunk threaded holes 13 is perpendicular to the axis of the fixing ring 1. The circumference of the fixing ring 1 is screwed to the corresponding countersunk threaded holes 13 by a plurality of bolts and then abuts against the probe 3 inside the fixing ring 1.
[0054] For example, the fixing ring 1 has four evenly spaced 5 mm recessed holes with internal threads for screwing in tapered screws. After passing through the countersunk threaded holes 13, the screws abut against the outside of the probe 3, thus connecting the fixing ring 1 to the logging probe 3. After connection, the outer surface of the fixing ring 1 is smooth without protrusions, and it does not affect the lowering and raising of the fixing ring 1 during logging. During the lowering of the probe 3, see... Figure 3 The diagram shows a detachment of the straightening element 2 from the fixing ring 1. The straightening element 2 stays at the corresponding stopping position, while the fixing ring 1 continues to move downward with the probe 3. When the fixing ring 1 is lifted, it will drive the straightening element 2, which is slidably connected to the probe 3, to move upward together.
[0055] Optionally, the fixing ring 1 includes a third part 11 and a fourth part 12 that are fastened to the outside of the probe 3, wherein the third part 11 and the fourth part 12 are detachably connected.
[0056] In one possible implementation, the connecting ends of the third part 11 and the fourth part 12 are provided with corresponding bosses, and the bosses of the third part 11 and the fourth part 12 are connected by vertically installed screws to achieve a detachable connection between the third part 11 and the fourth part 12, while ensuring the smoothness of the outer side of the fixing ring 1.
[0057] Based on the above embodiments, the specific usage method of this application can be as follows: A fixing ring 1 is installed on the probe 3 of the downhole instrument, then a centralizer 2 is installed on the probe 3, above the fixing ring 1, and then a logging cable is connected. When there is no change in diameter within the well 4, the instrument is successfully lowered. When a change in diameter is encountered, the fixing ring 1 continues to descend because its diameter is smaller than the borehole diameter of the well 4. The centralizer 2, whose diameter is larger than the borehole diameter below the change in diameter of the well 4, encounters resistance. However, because the centralizer 2 is slidably connected to the probe 3, during the lowering process... During the process, the straightener 2 stops moving down, and the downhole instrument continues to move down for measurement. Due to the presence of the straightener 2, the downhole instrument is almost centered in the drilling rig 4, ensuring that the downhole instrument can smoothly enter the lower small-diameter borehole of the variable-diameter drilling rig 4. When the downhole instrument is lifted from the bottom, it is lifted normally before the diameter change in the lower part of the drilling rig 4. When it reaches the diameter change point, due to the presence of the fixing ring 1, the fixing ring 1 will touch the straightener 2 that stopped at this point during the descent. The outer diameters of the fixing ring 1 and the straightener 2 are the same, and the fixing ring 1 drives the straightener 2 to move upward together.
[0058] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.
Claims
1. A logging pipe centering device, characterized in that, Includes fixing rings and straightening components; Both the fixing ring and the straightening member are sleeved on the outside of the probe. The fixing ring is fixedly connected to the probe, and the straightening member is slidably connected to the probe. The straightening member is located on the upper side of the fixing ring near the wellhead. The outer diameter of the fixed ring is smaller than the minimum diameter of the well, and the inner diameter of the fixed ring corresponds to the outer diameter of the probe. The minimum inner diameter of the stabilizer corresponds to the outer diameter of the probe. The outer surface of the stabilizer is lantern-shaped, rising from both ends to the middle along the axis of the stabilizer. The maximum diameter of the outer side of the stabilizer is greater than the diameter of the borehole below the diameter change position where the stabilizer stays in the well, and smaller than the diameter of the borehole above the diameter change position. The straightening component includes a raised component, a first connecting ring fixed to the upper end of the raised component, and a second connecting ring fixed to the lower end of the raised component. The outer diameter of the raised member gradually increases from the connection point with the first connecting ring and the second connecting ring toward the middle. The raised component is formed by combining multiple arc-shaped raised pieces. The upper end of each arc-shaped raised piece is fixedly connected to the first connecting ring, the lower end of each arc-shaped raised piece is fixedly connected to the second connecting ring, and the middle part of each arc-shaped raised piece protrudes away from the axis of the straightening component. The first connecting ring includes a detachably connected first half-ring and a second half-ring, and the second connecting ring includes a detachably connected third half-ring and a fourth half-ring. The positions of the first half-ring and the third half-ring are vertically corresponding. The first half-ring and the third half-ring are connected by multiple arc-shaped raised pieces, and the second half-ring and the fourth half-ring are also connected by multiple arc-shaped raised pieces.
2. The logging pipe stabilizer according to claim 1, characterized in that, The straightening component includes a first part and a second part that are fastened and sleeved on the outside of the probe, and the first part and the second part are detachably connected.
3. A logging pipe stabilizer according to claim 1, characterized in that, A first protrusion is provided at the end of the first half-ring near the second half-ring. The vertical thickness of the first protrusion is less than the thickness of the first half-ring. A second protrusion is provided at the end of the second half-ring near the first half-ring to cooperate with the first protrusion. The first protrusion and the corresponding second protrusion are detachably connected. The third half-ring has a third protrusion at its end near the fourth half-ring. The vertical thickness of the third protrusion is less than the thickness of the third half-ring. The fourth half-ring has a fourth protrusion at its end near the third half-ring, corresponding to the third protrusion. The third protrusion and the corresponding fourth protrusion are detachably connected.
4. A logging pipe stabilizer according to claim 3, characterized in that, The first protrusion is disposed near the lower surface of the first half-ring, and the third protrusion is disposed near the upper surface of the third half-ring; A first horizontal pin hole is provided between the upper surface of the first boss and the lower surface of the second boss, and the axis of the first horizontal pin hole is perpendicular to the axis of the straightening member. A second horizontal pin hole is provided between the lower surface of the third boss and the upper surface of the fourth boss, and the axis of the second horizontal pin hole is perpendicular to the axis of the straightening member.
5. A logging pipe centering device according to claim 3, characterized in that, The first boss and the corresponding second boss are fitted with a vertical first countersunk hole and connected by a first countersunk bolt; the third boss and the corresponding fourth boss are fitted with a vertical second countersunk hole and connected by a second countersunk bolt.
6. A logging pipe stabilizer according to claim 1, characterized in that, The circumference of the fixing ring is provided with multiple countersunk threaded holes, the axis of the countersunk threaded holes is perpendicular to the axis of the fixing ring, and the circumference of the fixing ring is screwed to the corresponding countersunk threaded holes by multiple bolts and then abuts against the probe inside the fixing ring.
7. A logging pipe stabilizer according to claim 1, characterized in that, The fixing ring includes a third part and a fourth part that are fastened to the outside of the probe, and the third part and the fourth part are detachably connected.