A multi-stage combined sealed screw drill bit

Abstract

This utility model relates to a multi-stage combined sealing screw drill bit applied in the field of screw drill bits. It includes a screw drill bit body, which comprises a shell. A drive shaft assembly is housed within the shell's inner cavity. A drill bit is mounted on the lower end of the drive shaft assembly, and its lower end movably penetrates the shell. A steel ring is fitted over the drill bit. An inner shell is rotatably fitted onto the outer surface of the drive shaft assembly. The lower end of the inner shell is fixedly connected to the upper end of the steel ring. A rubber tube is fixedly fitted onto the outer surface of the inner shell. Utilizing the water-swelling property of the rubber tube, when micro-cracks appear in the shell causing mud and sand to intrude, the tube expands and seals the micro-cracks. A floating sealing body, composed of springs, sliding rods, and sliding plates, adapts to the vibration of the drill bit, thereby forming dynamic pressure compensation for mechanical sealing. This effectively prevents mud and sand from intruding into the shell and damaging its internal components, thus effectively extending the service life of the screw drill bit.

Description

Technical Field

[0001] This utility model relates to a screw drill bit, and more particularly to a multi-stage combined sealed screw drill bit applied in the field of screw drill bits. Background Technology

[0002] A screw drill is an energy conversion device that converts the pressure energy of a liquid into mechanical energy. It consists of a bypass valve, motor, TC bearing, thrust bearing, universal joint, drive shaft, and anti-drop device. Screw drills are essential tools in natural gas and oil drilling and extraction projects.

[0003] The specification of Chinese Patent Publication No. CN218324765U discloses a large-displacement screw drill. This utility model, through the combination of the above-mentioned structures, realizes the injection of liquid to increase pressure by setting a drainage groove, and the continuous and repeated rotation of the bypass valve to discharge mud. In addition, the duckbill single-way valve can play a one-way material passage effect to prevent backflow, which brings convenience to the workers.

[0004] When screw drills operate in hard formations for extended periods, the hard working environment constantly scrapes against the drill bit's outer casing, causing micro-cracks that allow mud and sand to infiltrate. Furthermore, the drill bit's contact with rocks and other materials during operation generates significant vibrations, creating large gaps at the connection between the outer casing and the drill bit. This allows mud and sand to enter the casing through these gaps and micro-cracks, ultimately damaging components such as the drive shaft assembly. Utility Model Content

[0005] In view of the above-mentioned prior art, the technical problem to be solved by this utility model is that when the screw drill bit is operating in hard formations for a long time, the harsh working environment will not only cause micro-cracks in the shell, but also cause large gaps at the connection between the shell and the drill bit, which will cause mud and sand to enter the shell and damage the internal parts.

[0006] To address the aforementioned problems, this utility model provides a multi-stage combined sealed screw drill bit, comprising a screw drill bit body. The screw drill bit body includes a shell, and a drive shaft assembly is housed within the inner cavity of the shell. A drill bit is mounted on the lower end of the drive shaft assembly, and the lower end of the drill bit movably penetrates the shell. A steel ring is fitted over the drill bit. An inner shell is rotatably fitted onto the outer surface of the drive shaft assembly. The lower end of the inner shell is fixedly connected to the upper end of the steel ring. A rubber tube is fixedly fitted onto the outer surface of the inner shell. The outer surface of the steel ring is fixedly connected to the inner wall of the shell. A receiving groove is chiseled at the lower end of the steel ring. Multiple mounting holes are chiseled on the inner top wall of the receiving groove. A sliding plate is provided within the receiving groove, and both the upper and lower ends of the sliding plate are fixedly connected to... The upper spring is located in the mounting hole and is fixedly connected to the inner top wall of the mounting hole. A sliding rod is also fixedly connected to the inner top wall of the mounting hole. A carbon ring is inserted into the receiving groove. An adjustment groove is chiseled at the upper end of the carbon ring. The lower end of the sliding rod moves through a spring, a sliding plate, and another spring in sequence and extends into the adjustment groove. The lower end of the lower spring is fixedly connected to the carbon ring. Multiple sealing rings are placed between the carbon ring and the drill bit, and multiple sealing rings are placed between the carbon ring and the inner wall of the outer shell. A moving ring is fixedly fitted on the outer surface of the drill bit. The upper end of the moving ring is rotatably connected to the lower end of the carbon ring, and the lower end of the moving ring moves through to the lower end of the outer shell. A telescopic ring is fixedly connected to the lower end of the outer shell.

[0007] In the aforementioned multi-stage combined sealing screw drill bit, the rubber tube expands when it comes into contact with water. When micro-cracks appear in the outer shell and mud and sand enter, the micro-cracks are expanded and sealed. A floating seal body composed of springs, slide rods, and sliding plates is formed, which adapts to the vibration of the drill bit, thereby forming dynamic pressure compensation for mechanical sealing. This effectively prevents mud and sand from entering the inner shell and damaging its internal parts, thus effectively extending the service life of the screw drill bit.

[0008] As a further improvement of this application, the outer surface of the rubber tube is fitted with the inner wall of the outer shell, and the rubber tube is made of a water-swellable rubber material.

[0009] As a further improvement of this application, the inner walls of both the steel ring and the carbon ring are in contact with the outer surface of the drill bit, and the outer surface of the moving ring is in contact with the inner wall of the outer shell.

[0010] As a further improvement of this application, multiple mounting holes are arranged in a ring array around the steel ring, and the outer surface of the slide plate slides in contact with the inner wall of the receiving groove.

[0011] As another improvement of this application, both sealing ring one and sealing ring two are made of high-temperature resistant elastic material, and the diameter of sealing ring two is larger than the diameter of sealing ring one.

[0012] As another improvement of this application, a positioning frame is fixedly embedded inside the rubber tube, and the positioning frame is in the shape of a honeycomb grid.

[0013] In summary, in practical applications, when the outer shell develops micro-cracks due to long-term scraping, and mud and sand infiltrate the shell, the moisture carried by the mud and sand comes into contact with the rubber tube, causing the rubber tube to expand and fill the crack gaps, thereby sealing the micro-cracks and self-repairing the outer shell. This effectively prevents mud and sand from entering the shell through the micro-cracks. At the same time, when the drill bit makes hard contact with hard formations, the drill bit generates significant vibration, causing the rotating ring to vibrate. At this time, the two springs and the sliding plate on the carbon ring move slightly axially. The upper and lower springs buffer the vibration impact in both directions, forming a floating seal that adapts to the vibration of the rotating ring, thus forming dynamic pressure compensation for mechanical sealing. This effectively prevents mud and sand from entering the shell and damaging its internal parts, thereby effectively extending the service life of the screw drill bit. Attached Figure Description

[0014] Figure 1 This is a three-dimensional structural diagram of the first embodiment of this application;

[0015] Figure 2 This is a structural cross-sectional view of the first embodiment of this application;

[0016] Figure 3 This is a schematic diagram of the rubber tube structure according to the first embodiment of this application;

[0017] Figure 4 This is a schematic diagram of the sealing ring II structure according to the first embodiment of this application;

[0018] Figure 5 This is a cross-sectional view of the steel ring structure according to the first embodiment of this application;

[0019] Figure 6 This is a bottom view of the steel ring structure according to the first embodiment of this application;

[0020] Figure 7 This is a schematic diagram of the dynamic ring structure according to the first embodiment of this application;

[0021] Figure 8 This is a schematic diagram of the positioning frame structure according to the second embodiment of this application.

[0022] Explanation of the labels in the diagram:

[0023] 1. Outer shell, 2. Drive shaft assembly, 3. Drill bit, 4. Steel ring, 5. Inner shell, 6. Rubber tube, 7. Receiving groove, 8. Mounting hole, 9. Slide plate, 10. Spring, 11. Slide rod, 12. Carbon ring, 13. Adjustment groove, 14. Sealing ring I, 15. Sealing ring II, 16. Dynamic ring, 17. Telescopic ring, 18. Positioning frame. Detailed Implementation

[0024] The two embodiments of this application will be described in detail below with reference to the accompanying drawings.

[0025] First implementation method:

[0026] Figures 1-3 The diagram shows a multi-stage combined sealed screw drill, comprising a screw drill body, a drive shaft assembly 2 housed in the inner cavity of a housing 1, a drill bit 3 mounted on the lower end of the drive shaft assembly 2, the lower end of the drill bit 3 movably penetrating the housing 1, a steel ring 4 fitted over the drill bit 3, an inner housing 5 rotatably fitted on the outer surface of the drive shaft assembly 2, the lower end of the inner housing 5 being fixedly connected to the upper end of the steel ring 4, a rubber tube 6 fixedly fitted on the outer surface of the inner housing 5, the outer surface of the rubber tube 6 being in contact with the inner wall of the housing 1, the rubber tube 6 being made of water-swellable rubber material, when the housing 1 cracks and seeps in mud and water, the rubber tube 6 expands and fills the crack gaps, sealing the cracks in the housing 1, thereby self-repairing the housing 1, even if the rubber tube 6 is damaged, the inner housing 5 can still provide secondary protection against mud and sand, thereby effectively preventing mud and sand from entering the drive shaft assembly 2, the outer surface of the steel ring 4 being fixedly connected to the inner wall of the housing 1.

[0027] Figure 5 and Figure 6 The diagram shows that: a receiving groove 7 is carved at the lower end of the steel ring 4, and multiple mounting holes 8 are carved on the inner top wall of the receiving groove 7. The mounting holes 8 are arranged in a ring array around the steel ring 4. A sliding plate 9 is provided in the receiving groove 7, and the outer surface of the sliding plate 9 slides in contact with the inner wall of the receiving groove 7. Springs 10 are fixedly connected to both the upper and lower ends of the sliding plate 9. The upper spring 10 is located in the mounting hole 8 and is fixedly connected to the inner top wall of the mounting hole 8. A sliding rod 11 is also fixedly connected to the inner top wall of the mounting hole 8. A carbon ring 12 is inserted into the receiving groove 7. The inner walls of the steel ring 4 and the carbon ring 12 are in contact with the outer surface of the drill bit 3. An adjusting groove 13 is carved at the upper end of the carbon ring 12. The sliding rod 11... The lower end of 1 moves through a spring 10, a slide plate 9, and another spring 10 in sequence and extends into the adjusting groove 13. The lower end of the lower spring 10 is fixedly connected to the carbon ring 12. When the drill bit 3 vibrates or even tilts, the moving ring 16 presses the carbon ring 12, causing the two springs 10 to deform and the slide plate 9 to move axially. The upper and lower springs 10 buffer the vibration impact in both directions, forming a floating seal. It adapts to the displacement with the vibration of the moving ring 16, thereby forming dynamic pressure compensation for mechanical sealing. This effectively avoids the formation of a large gap between the outer shell 1 and the drill bit 3 due to large vibrations, thus effectively preventing mud and sand from entering the interior of the outer shell 1 through the gap.

[0028] Figure 2 , Figure 4 , Figure 5 and Figure 7The diagram shows that multiple sealing rings 14 are placed between the carbon ring 12 and the drill bit 3, and multiple sealing rings 15 are placed between the carbon ring 12 and the inner wall of the outer shell 1. Both sealing rings 14 and 15 are made of high-temperature resistant elastic material. The diameter of sealing ring 15 is larger than that of sealing ring 14. Sealing ring 14 can seal the annular gap between the drill bit 3 and the carbon ring 12, effectively preventing sand-laden mud from rising along the surface of the drill bit 3. Its elastic deformation can compensate for the radial runout of the drill bit 3. Sealing ring 15 can effectively... The drilling slurry is blocked from seeping down through the gap between the inner shell 1 and the carbon ring 12. At the same time, the carbon ring 12 is elastically supported to float. A moving ring 16 is fixedly sleeved on the outer surface of the drill bit 3. The outer surface of the moving ring 16 is in contact with the inner wall of the shell 1. The upper end of the moving ring 16 is rotatably connected to the lower end of the carbon ring 12. The lower end of the moving ring 16 moves through to the lower end of the shell 1. A telescopic ring 17 is fixedly connected to the lower end of the shell 1. The telescopic ring 17 can absorb the axial vibration of the drill bit 3 and convert the drilling pressure fluctuation into the elastic deformation of the telescopic ring 17.

[0029] When using this screw drill bit, if the outer casing 1 develops micro-cracks due to long-term scraping, and mud and sand enter the outer casing 1, the moisture carried by the mud and sand comes into contact with the rubber tube 6, causing the rubber tube 6 to expand and fill the crack gaps, thereby sealing the micro-cracks and self-repairing the outer casing 1. This effectively prevents mud and sand from entering the outer casing 1 through the micro-cracks. At the same time, when the drill bit 3 makes hard contact with hard formations, the drill bit 3 generates significant vibration, causing the rotating ring 16 to vibrate. At this time, the two springs 10 and the slide plate 9 on the carbon ring 12 move slightly axially. The upper and lower springs 10 buffer the vibration impact in both directions, forming a floating seal. The upper and lower springs 10 adapt to the displacement with the vibration of the rotating ring 16, thereby forming dynamic pressure compensation for mechanical sealing. This effectively prevents mud and sand from entering the inner casing 1 and damaging its internal parts, thus effectively extending the service life of the screw drill bit.

[0030] Second implementation method:

[0031] This embodiment adds a positioning frame 18 to the first embodiment, while the rest remains the same as the first embodiment.

[0032] Figure 8 As shown: A positioning frame 18 is fixedly embedded inside the rubber tube 6, and the positioning frame 18 is in the shape of a honeycomb grid.

[0033] When the rubber tube 6 expands upon contact with water, the honeycomb-shaped positioning frame 18 separates the various parts of the rubber tube 6, effectively limiting the radial expansion range, thereby constraining the disorderly expansion of the rubber and maintaining the integrity of the overall structure.

[0034] In light of current practical needs, the above-described embodiments adopted in this application are not limited to these. Any changes made within the scope of knowledge possessed by those skilled in the art without departing from the concept of this application still fall within the protection scope of this utility model.

Claims

1. A multi-stage combination sealed screw drill, comprising a screw drill body, characterized in that: The screw drill body includes a shell (1), the inner cavity of the shell (1) is provided with a drive shaft assembly (2), the lower end of the drive shaft assembly (2) is equipped with a drill bit (3), the lower end of the drill bit (3) movably penetrates the shell (1), the drill bit (3) is fitted with a steel ring (4), the outer surface of the drive shaft assembly (2) is rotatably fitted with an inner shell (5), the lower end of the inner shell (5) is fixedly connected to the upper end of the steel ring (4), the outer surface of the inner shell (5) is fixedly fitted with a rubber tube (6), and the outer surface of the steel ring (4) is fixedly connected to the inner wall of the shell (1). The lower end of the steel ring (4) is chiseled with a receiving groove (7), and the inner top wall of the receiving groove (7) is chiseled with multiple mounting holes (8). The receiving groove (7) is provided with a sliding plate (9), and the upper and lower ends of the sliding plate (9) are fixedly connected with springs (10). The upper spring (10) is located in the mounting hole (8) and is fixedly connected to the inner top wall of the mounting hole (8). The inner top wall of the mounting hole (8) is also fixedly connected with a sliding rod (11). A carbon ring (12) is inserted into the receiving groove (7). The upper end of the carbon ring (12) is chiseled with an adjustment groove (13). The lower end of the sliding rod (11) moves through one spring (10), the sliding plate (9) and another spring (10) in sequence and extends into the adjustment groove (13). The lower end of the lower spring (10) is fixedly connected to the carbon ring (12). Multiple sealing rings (14) are placed between the carbon ring (12) and the drill bit (3), and multiple sealing rings (15) are placed between the carbon ring (12) and the inner wall of the outer shell (1). A moving ring (16) is fixedly fitted on the outer surface of the drill bit (3). The upper end of the moving ring (16) is rotatably connected to the lower end of the carbon ring (12), and the lower end of the moving ring (16) moves through to the lower end of the outer shell (1). A telescopic ring (17) is fixedly connected to the lower end of the outer shell (1).

2. A multi-stage, combined seal screw-in drill according to claim 1, characterized in that: The outer surface of the rubber tube (6) is attached to the inner wall of the outer shell (1), and the rubber tube (6) is made of water-swellable rubber material.

3. The multi-stage combined sealed screw drill bit according to claim 1, characterized in that: The inner walls of the steel ring (4) and the carbon ring (12) are in contact with the outer surface of the drill bit (3), and the outer surface of the moving ring (16) is in contact with the inner wall of the outer shell (1).

4. The multi-stage combined sealed screw drill bit according to claim 1, characterized in that: Multiple mounting holes (8) are arranged in a ring array around the steel ring (4), and the outer surface of the slide plate (9) slides in contact with the inner wall of the receiving groove (7).

5. A multi-stage combined sealed screw drill bit according to claim 1, characterized in that: Both the first sealing ring (14) and the second sealing ring (15) are made of high-temperature resistant elastic material, and the diameter of the second sealing ring (15) is larger than the diameter of the first sealing ring (14).

6. A multi-stage combined sealed screw drill bit according to claim 1, characterized in that: A positioning frame (18) is fixedly embedded inside the rubber tube (6), and the positioning frame (18) is honeycomb grid.

Images