While-drilling well body cleaning tool

Abstract

The utility model discloses a while-drilling well body cleaning tool. The while-drilling well body cleaning tool comprises a core shaft and an outer barrel arranged on the outer side of the core shaft in a sleeving mode. The length of the outer cylinder is smaller than that of the mandrel, and a slag storage cavity with a closed lower end and an open upper end is formed between the outer cylinder and the mandrel. According to the while-drilling well body cleaning tool, underground fragments and falling objects can be well cleaned, the bottom of the well is kept clean, the service life of the drill bit is prolonged, and underground accidents are reduced and prevented.

Description

Technical Field

[0001] This utility model relates to the field of oil and gas field tools technology, specifically to a wellbore cleaning tool used during drilling. Background Technology

[0002] Sticking is a common problem encountered during drilling operations, caused by a multitude of factors. Once stuck, the process of freeing the pipe is extremely complex. Improper freeing methods can lead to wellbore collapse, drill string falling into or being buried, and can easily trigger serious consequences such as well kicks and blowouts. Therefore, throughout the drilling process, numerous process control measures are employed to prevent sticking, such as controlling drilling speed, performing short trips, controlling the solids content in the drilling mud, and even adding a deep well cleaning step after complete tripping. These methods significantly impact drilling efficiency and increase drilling costs. Utility Model Content

[0003] To address the aforementioned issues, this application provides a wellbore cleaning tool that can effectively clean up large rock fragments and various solid fragments generated during well drilling without adding to the normal drilling schedule of drill string tripping. This allows drill cuttings and solid materials at the bottom of the well to be returned to the surface more effectively throughout the drilling process, resulting in a smoother wellbore and significantly reducing the risk of stuck drill bit during drilling.

[0004] The objective of this utility model is achieved through the following technical solution: a wellbore cleaning tool, comprising:

[0005] The mandrel and an outer cylinder sleeved on the outside of the mandrel; the length of the outer cylinder is shorter than the length of the mandrel, and a slag storage cavity is formed between the outer cylinder and the mandrel, which is closed at the bottom and open at the top.

[0006] The outer cylinder of this invention has a large diameter and a small annular gap between it and the wellbore wall. The upward flow velocity of the fluid in the well is relatively fast at this position, which can carry up debris such as carbide teeth, drill bit bearings, and large solid materials from the bottom of the well. However, because the diameter of the mandrel is small, the annular gap between it and the well wall is large. When the drilling fluid returns to the top of the outer cylinder, the upward flow velocity of the drilling fluid drops sharply due to the increased fluid flow area, forming a vortex. Its carrying capacity is also greatly reduced, so that the heavier debris in the drilling fluid falls into the slag storage chamber and is retrieved with the drill bit. This keeps the bottom of the well clean, improves the service life of the drill bit, and reduces and prevents downhole accidents.

[0007] The mandrel has a narrow section with a decreasing diameter, and the upper opening of the slag storage chamber extends to the outside of the narrow section. By setting the narrow section, the annular space between the narrow section and the well wall is further increased, reducing the drilling fluid flow rate and allowing heavier debris in the drilling fluid to fall into the slag storage chamber more effectively.

[0008] The mandrel is coaxially arranged with the outer cylinder so that the slag storage chamber forms a uniform annular cavity, which can better receive falling debris.

[0009] The outer cylinder is equipped with a filter screen on its wall, allowing drilling fluid in the slag storage chamber to be discharged through the filter screen, forming a circulation and continuously carrying away the debris upwards.

[0010] The lower end of the outer cylinder is provided with a slag discharge door to facilitate the discharge of residue from the slag storage chamber.

[0011] The mandrel is provided with a connector, and the connector is provided with a plurality of snap-fit ​​protrusions in the circumferential direction. The lower end of the outer cylinder is provided with a plurality of snap-fit ​​cavities that engage with the snap-fit ​​protrusions.

[0012] The outer wall of the mandrel is provided with a connecting block, and the wall of the outer cylinder is connected to the connecting block by connecting screws.

[0013] Compared with the prior art, this application has the following beneficial effects: The outer cylinder of this utility model has a larger diameter and a smaller annular gap between it and the wellbore wall. The upward flow velocity of the fluid in the well is faster at this position, which can carry up debris such as carbide teeth, drill bit bearings, and large solid materials from the bottom of the well. Since the diameter of the mandrel is smaller and the annular gap between it and the well wall is larger, when the drilling fluid returns to the top of the outer cylinder, the upward flow velocity of the drilling fluid drops sharply due to the increased fluid flow area, forming a vortex. Its carrying capacity is also greatly reduced, so that the heavier debris in the drilling fluid falls into the slag storage chamber and is retrieved with the drill bit, thereby keeping the bottom of the well clean, improving the service life of the drill bit, and reducing and preventing downhole accidents.

[0014] This invention utilizes a cleaning mechanism during pipe delivery to remove obstructions and foreign objects between the inner and outer wellbores, facilitating the lowering of the delivery pipe into the annulus requiring sealing. Furthermore, the pipe winding device prevents the delivery pipe from being left haphazardly within the well site, simplifying well site management.

[0015] Some of the additional features of this application will be described in the following description. These additional features will become apparent to those skilled in the art upon examination of the following description and the accompanying drawings, or upon understanding the production or operation of the embodiments. The features disclosed in this application can be implemented and achieved through the practice or use of various methods, means, and combinations thereof with respect to the specific embodiments described below. Attached Figure Description

[0016] The accompanying drawings, which are provided to further illustrate this application and constitute a part of this application, illustrate exemplary embodiments of this application and are used to explain this application, but do not constitute a limitation thereof. In the drawings, the same reference numerals denote the same components.

[0017] Figure 1 This is a cross-sectional view of the present invention.

[0018] Figure 2 This is a top sectional view of the present invention.

[0019] The reference numerals in the above figures are: 1-mandrel, 2-outer cylinder, 3-filter screen, 4-slag discharge door, 5-clamping protrusion, 6-joint, 7-connecting screw, 8-connecting block, 9-slag storage chamber, 11-narrow diameter section. Detailed Implementation

[0020] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments.

[0021] Example

[0022] like Figure 1 , 2 As shown in the figure, this embodiment discloses a wellbore cleaning tool, which includes a mandrel 1 and an outer cylinder 2. The mandrel 1 is a hollow structure, and drilling fluid is injected into the wellbore from inside the mandrel 1 during drilling. The inner diameter of the outer cylinder 2 is larger than the outer diameter of the mandrel 1, and its length is shorter than the length of the mandrel 1. The outer cylinder 2 is sleeved on the outside of the mandrel 1, and a slag storage cavity 9, closed at the lower end and open at the upper end, is formed between the outer cylinder 2 and the mandrel 1.

[0023] Specifically, the mandrel 1 is provided with a connector 6, and the connector 6 is provided with a plurality of snap-fit ​​protrusions 5 circumferentially. Correspondingly, the lower end of the outer cylinder 2 is provided with a plurality of snap-fit ​​cavities that match the snap-fit ​​protrusions 5. During installation, the snap-fit ​​protrusions 5 on the mandrel 1 snap into the snap-fit ​​cavities on the outer cylinder 2, thereby connecting the mandrel 1 and the connector 6 together.

[0024] In addition, the outer wall of the mandrel 1 is provided with several connecting blocks 8. During installation, the cylinder wall of the outer cylinder 2 is connected to the connecting blocks 8 by connecting screws 7, thereby fixing the mandrel 1 and the outer cylinder 2. The connecting blocks 8 are spaced apart, so the connecting blocks 8 will not obstruct the solid phase from falling into the slag storage chamber 9.

[0025] During use, the entire wellbore cleaning tool is mounted on the tool string and positioned above the scraper, drill bit, and grinding or milling shoe. It is lowered into the well along with the tool string. Due to the large diameter of the outer cylinder 2, the annular gap between it and the wellbore sidewall is small. When the drilling fluid returns to the surface, the upward flow velocity at this location is relatively fast, creating a negative pressure. This carries away debris generated during operation, as well as large solid materials such as carbide teeth and drill bit bearings that fall from the drill string. Conversely, due to the small diameter of the mandrel 1, the annular gap between it and the well wall is large. When the drilling fluid returns to the surface above the outer cylinder 2, the upward flow velocity of the drilling fluid drops sharply due to the increased flow area, forming a vortex. Its carrying capacity is also greatly reduced, causing heavier debris in the drilling fluid to fall into the slag storage chamber 9 and be retrieved during tripping. This keeps the bottom of the well clean, improves the service life of the drill bit, and reduces and prevents downhole accidents.

[0026] The outer cylinder 2 is equipped with a filter screen 3. Drilling fluid entering the slag storage chamber 9 can be discharged through the filter screen 3, while solids remain in the slag storage chamber 9. After being discharged from the filter screen 3, the drilling fluid in the slag storage chamber 9 returns upward along the gap between the outer cylinder 2 and the well wall, carrying solids again, thus forming a circulation that continuously carries away residual cuttings, keeping the bottom of the well clean.

[0027] In specific settings, such as Figure 2 As shown, the mandrel 1 and the outer cylinder 2 are coaxially arranged, so that the slag storage chamber 9 forms a uniform annular cavity, which can better receive the falling debris.

[0028] In addition, the mandrel 1 is provided with a narrow diameter section 11, that is, the diameter of the narrow diameter section 11 is smaller than that of other positions on the mandrel 1; the upper opening of the slag storage chamber 9 extends to the outside of the narrow diameter section 11. By providing the narrow diameter section 11, the annular space clearance between the narrow diameter section 11 and the well wall is further increased, further reducing the drilling fluid flow rate, and allowing heavier debris in the drilling fluid to fall into the slag storage chamber 9 more effectively.

[0029] The lower end of the outer cylinder 2 is equipped with a slag discharge door 4. After the work is completed, the tool string is pulled out and the slag discharge door 4 is opened to discharge the residue in the slag storage chamber 9. When there is a lot of residue or the residue is large, the connecting screw 7 can also be removed to remove the outer cylinder from the mandrel 1 to clean the residue.

[0030] The drilling cleaning tool in this embodiment can effectively clean up debris and debris in the well, keep the bottom of the well clean, improve the service life of the drill bit, and reduce and prevent downhole accidents.

[0031] It should be noted that all features disclosed in this specification, or all steps in all methods or processes disclosed, may be combined in any way, except for mutually exclusive features and / or steps.

[0032] Furthermore, the specific embodiments described above are exemplary. Those skilled in the art can devise various solutions inspired by the disclosure of this utility model, and these solutions all fall within the scope of this utility model and its protection. Those skilled in the art should understand that this utility model specification and its drawings are illustrative and not intended to limit the scope of the claims. The scope of protection of this utility model is defined by the claims and their equivalents.

Claims

1. A drilling rig cleaning tool, characterized in that, include: The mandrel (1) and the outer cylinder (2) sleeved on the outside of the mandrel (1); the length of the outer cylinder (2) is shorter than the length of the mandrel (1), and a slag storage cavity (9) is formed between the outer cylinder (2) and the mandrel (1) with the lower end closed and the upper end open; the mandrel (1) is a hollow structure for injecting drilling fluid into the wellbore from the inside of the mandrel (1); The mandrel (1) is provided with a narrow diameter section (11) with a smaller diameter, and the upper opening of the slag storage chamber (9) extends to the outside of the narrow diameter section (11); The mandrel (1) is provided with a connector (6), and the connector (6) is provided with several snap-fit ​​protrusions (5) in the circumferential direction. The lower end of the outer cylinder (2) is provided with several snap-fit ​​cavities that engage with the snap-fit ​​protrusions (5).

2. The wellbore cleaning tool according to claim 1, characterized in that, The mandrel (1) and the outer cylinder (2) are coaxially arranged.

3. The wellbore cleaning tool according to claim 1, characterized in that, The outer cylinder (2) is provided with a filter screen (3) on its cylinder wall.

4. The drilling rig cleaning tool according to claim 1, characterized in that, The outer cylinder (2) is provided with a slag discharge door (4) on the lower end of the cylinder wall.

5. The wellbore cleaning tool according to claim 1, characterized in that, The outer wall of the mandrel (1) is provided with a connecting block (8), and the cylinder wall of the outer cylinder (2) is connected to the connecting block (8) by a connecting screw (7).

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