Drill rod fishing tool
By designing a drill pipe retrieval tool with a specially shaped threaded structure and alloy blocks, the problem of difficulty in clamping broken drill pipes was solved, achieving efficient retrieval of broken drill pipes and improving the operational efficiency of engineering geological exploration.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- WUXI GEOLOGICAL DRILLING EQUIP CO LTD
- Filing Date
- 2025-06-20
- Publication Date
- 2026-05-05
AI Technical Summary
Existing drill pipe retrieval tools are unable to effectively repair the cross-section of broken drill pipes and clamp them, resulting in low retrieval efficiency, especially when the drill bit gets stuck in fractured geological layers and cannot be retrieved.
Design a drill pipe retrieval tool, comprising a mandrel and a pressure sleeve. The mandrel consists of a body, a reducing section, a circumferential section, and a head. The pressure sleeve can slide along the axis and has a specially shaped threaded structure on its outer wall for self-tapping connection with the inner wall of the broken drill pipe. The circumferential section has an alloy block to trim the inner hole, and guide grooves and guide keys ensure stable sliding.
It achieves a tight connection with the broken drill rod, preventing it from falling off, improving retrieval efficiency, effectively repairing the inner hole, and ensuring the smooth removal of the broken drill rod.
Smart Images
Figure CN224200616U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of geological exploration technology, specifically to a drill pipe retrieval tool. Background Technology
[0002] In actual engineering geological exploration drilling, due to complex geological conditions, especially when encountering fractured geological layers, drill bits often get stuck. Since drill rods are connected in series, broken drill rods often fall together with the drill bit into the deep hole, making them impossible to retrieve and rendering the borehole and drilling tools unusable. To avoid losses, timely retrieval of the drill rods that have fallen into the hole is a necessary task for drilling personnel.
[0003] Existing drill pipe retrieval tools suffer from two main drawbacks: firstly, the irregular cross-section of the broken drill pipe makes it difficult to connect with the broken part; secondly, the small diameter of the drill pipe makes it difficult to secure the tool properly, leading to the tool easily falling off during lifting. Therefore, there is an urgent need to improve existing drill pipe retrieval tools to enable the trimming of the broken drill pipe's cross-section and effective securing with the broken part, thereby increasing retrieval efficiency. Utility Model Content
[0004] The purpose of this utility model is to provide a drill pipe retrieval tool to overcome the above-mentioned technical problems.
[0005] To achieve the above objectives, this utility model provides the following technical solution: a drill rod retrieval tool for retrieving broken drill rods, characterized in that the tool comprises: a mandrel, the mandrel being a cylindrical structure; a pressure sleeve, fitted onto the outside of the mandrel and capable of reciprocating along the axis of the mandrel; the outer diameter of the pressure sleeve gradually expands when sliding along a first direction; the outer diameter of the pressure sleeve gradually decreases when sliding along a second direction; the second direction is the opposite of the first direction; and the outer wall of the pressure sleeve is pressed tightly against the inner wall of the broken drill rod when sliding along the first direction.
[0006] In the above embodiment, the mandrel includes a body, a variable diameter portion, a circumferential portion, and a head connected sequentially along the first direction; the outer diameter of the body is smaller than the outer diameter of the circumferential portion; the outer diameter of the variable diameter portion smoothly transitions from the outer diameter of the body to the outer diameter of the circumferential portion along the first direction; the outer diameter of the head smoothly transitions from the outer diameter of the circumferential portion to a preset outer diameter along the first direction; the preset outer diameter is smaller than the outer diameter of the circumferential portion; and the outer diameter of the circumferential portion is smaller than the inner diameter of the fractured drill rod.
[0007] In some possible implementations, the mandrel further includes a connecting portion;
[0008] The connecting part is connected to one end of the body opposite to the variable diameter part.
[0009] In some possible implementations, the drill pipe retrieval tool further includes a connecting shaft: the connecting shaft is sleeved on the outside of the connecting portion; the outer diameter of the connecting shaft is larger than the outer diameter of the pressure sleeve, and the connecting shaft abuts against the pressure sleeve.
[0010] In some possible implementations, the mandrel further includes a plurality of alloy blocks disposed on the circumferential portion; the alloy blocks are disposed protruding from the circumferential portion; the plurality of alloy blocks are arranged in a uniform circumferential array with the axis of the mandrel as the axis.
[0011] In some possible implementations, the mandrel further includes a blocking portion; the blocking portion protrudes from the outer wall of the body; the pressure sleeve is provided with a stepped hole that engages with the blocking portion.
[0012] In some possible implementations, the mandrel further includes a plurality of grooves disposed in the variable diameter portion; the grooves are recessed toward the axis of the mandrel; the plurality of grooves are arranged in a uniform circumferential array with the axis of the mandrel as the center.
[0013] In this embodiment, a special-shaped thread structure is provided on the outer wall of the pressure sleeve near the end of the variable diameter section.
[0014] In some possible implementations, the pressure sleeve further includes a plurality of guide grooves; the guide grooves are correspondingly arranged with respect to the grooves, and the opening direction of the guide grooves faces the variable diameter portion; the plurality of guide grooves are arranged in a uniform circumferential array with the axis of the pressure sleeve as the axis.
[0015] In some possible implementations, the drill pipe retrieval tool further includes a plurality of guide keys corresponding to the groove, the guide keys being disposed within the groove; the guide groove slides along the axis of the mandrel in a first direction or a second direction under the constraint of the guide keys.
[0016] Compared with the prior art, the drill rod retrieval tool of this utility model has the following advantages: by setting a special shaped thread structure on the outer wall of the pressure sleeve, when it is pressed against the inner wall of the broken drill rod, a self-tapping effect is generated, and it is tightly connected to the broken drill rod and is not easy to fall off; by uniformly setting a number of alloy blocks on the outer circumference of the mandrel, the inner hole of the broken drill rod is repaired. Attached Figure Description
[0017] Figure 1 This is a schematic diagram of the overall structure of a drill pipe retrieval tool according to an embodiment of this application;
[0018] Figure 2 This is a schematic diagram of the overall structure of the mandrel in this application;
[0019] Figure 3This is a schematic diagram of the overall structure of the pressure sleeve in this application. Detailed Implementation
[0020] Embodiments embodying the features and advantages of this utility model will be described in detail in the following description. It should be understood that this utility model can have various variations in different examples, all of which do not depart from the scope of this utility model, and the descriptions and illustrations herein are for illustrative purposes only and not intended to limit this utility model.
[0021] It should be understood that although the terms "first," "second," etc., may be used herein to describe various features, these features should not be limited by these terms. The use of these terms is merely for distinction and should not be construed as indicating or implying relative importance. For example, without departing from the scope of the exemplary embodiments, a first feature may be referred to as a second feature, and similarly, a second feature may be referred to as a first feature.
[0022] In the description of this application, it should also be noted that, unless otherwise expressly specified and limited, the terms "set up," "connected," and "linked" should be interpreted broadly; for example, they can refer to a fixed connection, a detachable connection, or an integral molding; they can refer to a mechanical connection, a direct connection, a welding connection, or a connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the accompanying drawings and specific circumstances.
[0023] This application provides a drill pipe retrieval tool for retrieving broken drill pipes. Figure 1 This is a schematic diagram of the overall structure of a drill pipe retrieval tool according to an embodiment of this application, as shown below. Figure 1 As shown, the drill pipe retrieval tool includes: a mandrel 100, which is a cylindrical structure; a pressure sleeve 200, which is sleeved on the outside of the mandrel 100 and can reciprocate along the axis of the mandrel 100; when the pressure sleeve 200 slides along the first direction, its outer diameter gradually expands; when the pressure sleeve 200 slides along the second direction, its outer diameter gradually shrinks; the second direction is the opposite of the first direction; when the pressure sleeve 200 slides along the first direction, its outer wall is pressed tightly against the inner wall of the broken drill pipe.
[0024] In the above embodiments, preferably, the mandrel 100 is a hollow columnar structure.
[0025] In one specific embodiment of this application, such as Figure 2As shown, the mandrel 100 is composed of a body 101, a variable diameter section 102, a circumferential section 103, and a head 104 connected sequentially along a first direction; the outer diameter of the body 101 is smaller than the outer diameter of the circumferential section 103; the outer diameter of the variable diameter section 102 smoothly transitions from the outer diameter of the body 101 to the outer diameter of the circumferential section 103 along the first direction; the outer diameter of the head 104 smoothly transitions from the outer diameter of the circumferential section 103 to a preset outer diameter along the first direction; the preset outer diameter is smaller than the outer diameter of the circumferential section 103; the outer diameter of the circumferential section 103 is smaller than the inner diameter of the fractured drill rod.
[0026] In the above embodiments, preferably, the mandrel 100 is a one-piece molded structure.
[0027] In other embodiments of this application, such as Figure 2 As shown, the spindle 100 also includes a connecting portion 105; the connecting portion 105 is connected to one end of the body 101 opposite to the variable diameter portion 102.
[0028] In other embodiments of this application, such as Figure 1 As shown, the drill pipe retrieval tool also includes a connecting shaft 300, which is sleeved on the outside of the connecting part 105. The outer diameter of the connecting shaft 300 is larger than the outer diameter of the pressure sleeve 200, and the connecting shaft 300 abuts against the pressure sleeve 200.
[0029] In the above embodiments, preferably, the outer diameter of the connecting shaft 300 should be greater than the inner diameter of the broken drill rod, that is, during retrieval, the connecting shaft 300 does not enter the broken drill rod along with the pressure sleeve 200.
[0030] In the above embodiment, specifically, the connecting shaft 300 is threadedly connected to the connecting part 105, the connecting shaft 300 is provided with an internal thread, and the connecting part 105 is provided with an external thread.
[0031] In the above embodiments, specifically, the pressure sleeve 100 slides along a first direction, that is, slides away from the connecting shaft; the pressure sleeve 100 slides along a second direction, that is, slides closer to the connecting shaft.
[0032] In the above embodiment, preferably, the end of the connecting shaft 300 away from the mandrel 100 is provided with an internal thread structure. This design facilitates connection with the upper drill rod.
[0033] In one specific embodiment of this application, such as Figure 2 As shown, the mandrel 100 also includes a plurality of alloy blocks 106 disposed on the circumferential portion 103. The alloy blocks 106 protrude from the circumferential portion 102, and the plurality of alloy blocks 105 are uniformly arranged in a circular array around the axis of the mandrel 100. By designing the alloy blocks 106, it is easy to flatten the inner hole of the fractured drill rod.
[0034] In one specific embodiment of this application, such as Figure 2As shown, the mandrel 100 also includes a blocking part 107, which protrudes from the outer wall of the body 101; the pressure sleeve 200 is provided with a stepped hole that matches the blocking part 107.
[0035] In the above embodiment, preferably, the inner diameter of the end of the pressure sleeve 200 near the connecting shaft 300 matches the outer diameter of the body 100; the inner diameter of the end of the pressure sleeve 200 away from the connecting shaft 300 matches the outer diameter of the blocking part 107, so that when the pressure sleeve 200 slides along the first direction, it prevents the pressure sleeve 200 from sliding out of the variable diameter part 102.
[0036] In the above embodiments, preferably, the blocking part 107 has a ring-shaped structure, is sleeved on the outside of the body 101, and is disposed in the middle part of the body 101.
[0037] In one specific embodiment of this application, such as Figure 2 As shown, the mandrel 100 also includes a plurality of grooves 108 provided in the variable diameter section 102. The grooves 108 are recessed toward the axis of the mandrel 100, and the plurality of grooves 108 are arranged in a uniform circumferential array with the axis of the mandrel 100 as the axis.
[0038] In the above embodiments, preferably, as follows: Figure 1 and Figure 3 As shown, a special-shaped thread structure 201 is provided on the outer wall of the pressure sleeve 200 near the end of the variable diameter part 102.
[0039] In the above embodiments, such as Figure 3 As shown, the pressure sleeve 200 also includes several guide grooves 202, which are correspondingly arranged with the grooves 108. The opening direction of the guide grooves 202 faces the variable diameter part 102. The several guide grooves 202 are arranged in a uniform circumferential array with the axis of the pressure sleeve 200 as the axis.
[0040] In other embodiments of this application, such as Figure 1 As shown, the drill pipe retrieval tool also includes several guide keys 400 corresponding to the groove 108, with the guide keys 400 disposed within the groove 108; the guide groove 202 slides along the axis of the mandrel 100 in either a first or second direction under the constraint of the guide keys 400. By setting the guide keys 400 and the guide groove 202, the pressure sleeve 200 is made to slide in a fixed direction, preventing slippage.
[0041] In the above embodiment, preferably, the guide key 400 is connected to the variable diameter part 102 by bolt 500.
[0042] The working principle of this utility model is as follows: When it is necessary to retrieve a broken drill rod, the drill rod retrieval tool is lowered. Guided by 104, the retrieval tool is aligned with the inner hole of the broken drill rod. The alloy block 106 on the circumferential part 103 is used to flatten the inner hole of the broken drill rod so that the drill rod retrieval tool can penetrate deep into the broken drill rod. The pressure sleeve 200 slides along the first direction, that is, it slides into the depth of the borehole until the connecting shaft 300 abuts against the broken drill rod. At this time, the drill rod retrieval tool is pulled up. Due to the action of gravity and friction, the pressure sleeve 200 continues to move down along the fixed direction under the action of the guide key 400. It is opened by the variable diameter part 102. The special-shaped thread structure 201 on the outer wall of the pressure sleeve 200 forms a self-tapping effect with the inner wall of the broken drill rod, and is tightly connected to the inner wall of the broken drill rod. The heavier the broken drill rod, the more obvious the self-tapping effect is when it is pulled up. The operator can observe the value of the pressure gauge on the ground to determine whether the broken drill rod has been lifted. If the broken drill rod falls, the above steps can be repeated until the retrieval is completed. If the broken drill rod is too heavy, the blocking part 107 can also prevent the pressure sleeve 200 from sliding out of the reducing part 102.
[0043] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in a suitable manner in any one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.
[0044] Although the present invention has been described in detail through the above preferred embodiments, it should be understood that the above description should not be considered as a limitation of the present invention. Various modifications and substitutions to the present invention will be apparent to those skilled in the art after reading the above content. Therefore, the scope of protection of the present invention should be defined by the appended claims.
Claims
1. A drill pipe retrieval tool for retrieving broken drill pipes, characterized in that, The drill pipe retrieval tool includes: Mandrel, wherein the mandrel has a cylindrical structure; The pressure sleeve is fitted onto the outside of the mandrel and can reciprocate along the axis of the mandrel. As the pressure sleeve slides along the first direction, its outer diameter gradually increases; As the pressure sleeve slides along the second direction, its outer diameter gradually decreases; The second direction is the opposite of the first direction; When the pressure sleeve slides along the first direction, its outer wall is pressed tightly against the inner wall of the fractured drill rod.
2. The drill pipe retrieval tool as described in claim 1, characterized in that, The mandrel includes a body, a variable diameter section, a circumferential section, and a head that are connected sequentially along the first direction. The outer diameter of the main body is smaller than the outer diameter of the circumferential portion; The outer diameter of the variable diameter portion smoothly transitions from the outer diameter of the main body to the outer diameter of the circumferential portion along the first direction. The outer diameter of the head smoothly transitions from the outer diameter of the circumference to a preset outer diameter along the first direction. The preset outer diameter is smaller than the outer diameter of the circumference portion; The outer diameter of the circumference is smaller than the inner diameter of the fractured drill rod.
3. The drill pipe retrieval tool as described in claim 2, characterized in that, The mandrel also includes a connecting portion; The connecting part is connected to one end of the body opposite to the variable diameter part.
4. The drill pipe retrieval tool as described in claim 3, characterized in that, It also includes a connecting shaft: The connecting shaft is sleeved on the outside of the connecting part; The outer diameter of the connecting shaft is larger than the outer diameter of the pressure sleeve, and the connecting shaft abuts against the pressure sleeve.
5. The drill pipe retrieval tool as described in claim 2, characterized in that, The mandrel also includes several alloy blocks disposed on the circumference. The alloy block protrudes from the circumferential portion; Several alloy blocks are arranged in a uniform circular array with the axis of the mandrel as the center.
6. The drill pipe retrieval tool as described in claim 2, characterized in that, The mandrel also includes a blocking part; The blocking part protrudes from the outer wall of the body; the pressure sleeve is provided with a stepped hole that mates with the blocking part.
7. The drill pipe retrieval tool as described in claim 2, characterized in that, The mandrel also includes several grooves provided in the variable diameter section; The groove is recessed towards the axis of the mandrel; Several of the grooves are arranged in a uniform circular array with the axis of the mandrel as the center.
8. The drill pipe retrieval tool as described in claim 2, characterized in that, The outer wall of the pressure sleeve is provided with a special-shaped thread structure at one end near the diameter reducing part.
9. The drill pipe retrieval tool as described in claim 7, characterized in that, The pressure sleeve also includes several guide grooves; The guide groove is provided corresponding to the groove, and the opening direction of the guide groove is towards the variable diameter part; a plurality of guide grooves are arranged in a uniform circumferential array with the axis of the pressure sleeve as the axis.
10. The drill pipe retrieval tool as described in claim 9, characterized in that, It also includes a plurality of guide keys corresponding to the groove, the guide keys being disposed within the groove; the guide groove slides along the axis of the mandrel in a first direction or a second direction under the constraint of the guide keys.