Roller cone composite drill bit for breaking rocks

Abstract

The utility model belongs to the technical field of roller cone drill bits, and particularly relates to a roller cone composite drill bit used for breaking rock, the roller cone composite drill bit comprises a main body structure, PDC drill bits and roller cone bodies, the upper end of the side face of the main body structure is provided with a plurality of PDC drill bits distributed in an annular array mode, and the roller cone bodies are movably installed on the sides, close to each other, of the PDC drill bits; two symmetrically-arranged guide cylinders are embedded in the top of the main body structure, and a vertical force rod is installed in each guide cylinder in a sliding and penetrating mode. According to the utility model, when the cone main body on the PDC bit works, the driving motor is started synchronously and drives the shifting block to rotate, and then the shifting block shifts the follow-up shaft to move, so that the driving disc drives the vertical force rod to move up and down along the guide cylinder, and under the recovery of the elastic force of the compression spring, the vertical force rod is driven to move up and down. Furthermore, the central impact head can impact gaps among the cone main bodies to crush rocks falling into the middle, so that on one hand, high-efficiency rock crushing is facilitated, and on the other hand, loss increase caused by the fact that the rocks are clamped among the cones is avoided.

Description

A roller cone composite drill bit for rock breaking Technical Field

[0001] This utility model relates to a roller cone composite drill bit, specifically a roller cone composite drill bit for rock breaking. Background Technology

[0002] In the PDC+roller cone composite drill bit, the PDC fixed cutting blade structure rotates with the drill bit under torque drive, while the roller cone cutting structure rotates and moves downwards around the drill bit axis with the drill bit body, and the roller cones also rotate around their own axes. The cutting profiles of the roller cone cutting structure and the PDC fixed blade cutting overlap in the nose and shoulder areas at the axis and perimeter (conventional PDC drill bits are extremely prone to wear in the nose and shoulder areas). The roller cone cutting structure crushes and partially or completely destroys the formation in the nose and shoulder areas under limited stress. Therefore, the combined operation of the roller cone cutting structure and the PDC fixed blade cutting structure allows the composite drill bit to combine the advantages of both conventional roller cone drill bits and PDC drill bits. Thus, the PDC+roller cone composite drill bit can effectively complement the advantages of roller cone drill bits and PDC drill bits, enhancing the drill bit's adaptability to difficult-to-drill formations such as high-strength, highly abrasive, and heterogeneous formations.

[0003] With the continuous deepening of oil exploration and development, shallow and easily exploitable oil and gas resources are becoming increasingly scarce. Seeking oil and gas resources in deep strata and complex geological conditions is gradually becoming an important task in current onshore and offshore exploration and development. Roller cone and PDC composite drill bits perform excellently in deep, hard strata, breaking rocks through the combined action of the roller cone and PDC cutting teeth. However, during drilling, the low tooth density at the center of the roller cone and PDC composite drill bit, coupled with the high-frequency vibrations generated by the interaction between the drill bit and the rock, leads to severe wear of the drill teeth at the center, resulting in core-breaking failure. This makes it difficult to break the rock center and also limits the mechanical drilling speed of the drill bit. Therefore, this application designs a roller cone composite drill bit for rock breaking. Summary of the Invention

[0004] The main objective of this disclosure is to provide a roller cone composite drill bit for rock breaking, so as to effectively solve the problems raised by the inventors in the above-mentioned background art.

[0005] To achieve the above objectives, the technical solution adopted by this utility model is as follows:

[0006] A roller cone composite drill bit for rock breaking includes a main structure, a PDC drill bit, and roller cone bodies. Several PDC drill bits arranged in a circular array are installed on the upper side of the main structure. Roller cone bodies are movably installed on the adjacent side of each PDC drill bit. Two symmetrically arranged guide cylinders are embedded in the top of the main structure, and a vertical force rod is slidably installed through each guide cylinder. The top of the vertical force rod extends to the space between each roller cone body and a central impact head is fixedly installed thereon, with a gap between the central impact head and the roller cone body.

[0007] Preferably, a heat dissipation cavity is installed inside the main structure, and the upper end surface of the heat dissipation cavity is flush with the bottom of the guide cylinder. The bottom end of the vertical force rod extends into the heat dissipation cavity and a drive disk is fixedly installed thereon. A compression spring is fixedly connected between the top of the drive disk and the bottom of the guide cylinder, and the vertical force rod passes through the compression spring.

[0008] Preferably, a drive motor is fixedly installed on the side wall of the heat dissipation cavity, and a toggle block is fixedly installed on the output shaft of the drive motor. A follower shaft is fixedly installed on the front of the drive disk. The toggle block is located below the two follower shafts, and the length of the toggle block is greater than the distance between the two follower shafts.

[0009] Preferably, an isosceles trapezoidal key is fixedly installed on the upper end of the side of the main structure, and a positioning port is opened on the side of the PDC drill bit near the main structure, and the isosceles trapezoidal key is inserted into the positioning port. The PDC drill bit is fixedly installed on the main structure by reinforcing bolts.

[0010] Preferably, the roller cone body is fixedly mounted with evenly distributed cutting teeth, and the cutting teeth face away from the PDC drill bit. A central shaft is fixedly mounted on the side of the roller cone body near the PDC drill bit, and the central shaft is movably mounted inside the PDC drill bit. An annular groove is formed on the PDC drill bit, and several evenly distributed lubricating balls are movably mounted at the bottom of the annular groove. Several evenly distributed anti-deviation keys are fixedly mounted on the side of the roller cone body near the PDC drill bit, and the anti-deviation keys are slidably mounted in the annular groove and in contact with the lubricating balls.

[0011] Preferably, an installation joint is movably mounted on the bottom of the main structure.

[0012] In view of this, compared with the prior art, the beneficial effects of this utility model are:

[0013] (i) In this application, the evenly distributed PDC drill bit and roller cone body ensure the efficiency of rock breaking. Each PDC drill bit is installed independently so that it can be inspected or replaced individually. The installation method is stable and does not deviate, which improves the overall service life. The anti-deviation key on the roller cone body can slide along the lubricating balls in the annular groove, which is more flexible.

[0014] (ii) In this application, when the main body of the roller cone on the PDC drill bit is working, the drive motor is turned on synchronously, which will drive the actuating block to rotate. Then the actuating block will move the follower shaft, causing the drive disc to drive the vertical force rod to move up and down along the guide cylinder. Under the elastic force of the compression spring, the central impact head will hit the gap between the main bodies of each roller cone to break the rock that falls into the middle. On the one hand, this is conducive to the high efficiency of rock breaking, and on the other hand, it avoids the rock from getting stuck between the roller cones, which will lead to increased wear. Attached Figure Description

[0015] Figure 1 shows a cross-sectional view of the roller cone composite drill bit for rock breaking provided by this utility model;

[0016] Figure 2 shows a schematic diagram of the structure of the first part in Figure 1;

[0017] Figure 3 shows a schematic diagram of the structure of the second part in Figure 1;

[0018] Figure 4 shows a top view of the drive disk;

[0019] Figure 5 shows a bottom view of the main body of the roller cone.

[0020] icon:

[0021] 1-Main structure; 101-Isosceles trapezoidal key; 2-PDC drill bit; 201-Lubricating ball; 202-Positioning port; 203-Reinforcing bolt; 3-Roller body; 301-Central shaft; 302-Cutting teeth; 303-Anti-deviation key; 4-Mounting connector; 5-Guide cylinder; 6-Vertical force bar; 7-Central impact head; 8-Drive disc; 9-Compression spring; 10-Drive motor; 11-Actuating block; 12-Follower shaft. Detailed Implementation

[0022] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0023] Please refer to Figures 1-5. The present invention provides the following embodiments:

[0024] A roller cone composite drill bit for rock breaking includes a main structure 1, a PDC drill bit 2, and a roller cone body 3. Several PDC drill bits 2 arranged in a circular array are installed on the upper side of the main structure 1. A roller cone body 3 is movably installed on the side of each PDC drill bit 2 that is close to it. Two symmetrically arranged guide cylinders 5 are embedded in the top of the main structure 1, and a vertical force rod 6 is slidably installed through each guide cylinder 5. The top of the vertical force rod 6 extends between each roller cone body 3 and a central impact head 7 is fixedly installed there. A gap is left between the central impact head 7 and the roller cone body 3. A heat dissipation cavity is installed inside the main structure 1, and the upper end surface of the heat dissipation cavity is flush with the bottom of the guide cylinder 5. The bottom end of the vertical force rod 6 extends into the heat dissipation cavity and a drive disk 8 is fixedly installed there. A compression spring 9 is fixedly connected between the top of the drive disk 8 and the bottom of the guide cylinder 5, and the vertical force rod 6 passes through the compression spring 9. An installation joint 4 is movably installed at the bottom of the main structure 1.

[0025] Specifically, a drive motor 10 is fixedly installed on the side wall of the heat dissipation cavity, and a toggle block 11 is fixedly installed on the output shaft of the drive motor 10. A follower shaft 12 is fixedly installed on the front of the drive disk 8. The toggle block 11 is located below the two follower shafts 12, and the length of the toggle block 11 is greater than the distance between the two follower shafts 12.

[0026] Specifically, an isosceles trapezoidal key 101 is fixedly installed on the upper side of the main structure 1. A positioning port 202 is opened on the side of the PDC drill bit 2 near the main structure 1, and the isosceles trapezoidal key 101 is inserted into the positioning port 202. The PDC drill bit 2 is fixedly installed on the main structure 1 by reinforcing bolts 203, so that the PDC drill bit can be installed stably and is suitable for later maintenance and other operations.

[0027] Specifically, the roller cone body 3 is fixedly mounted with evenly distributed cutting teeth 302, and the cutting teeth 302 face away from the PDC drill bit 2. The roller cone body 3 is fixedly mounted with a central shaft 301 on the side close to the PDC drill bit 2, and the central shaft 301 is movably mounted inside the PDC drill bit 2. The PDC drill bit 2 has an annular groove, and several evenly distributed lubricating balls 201 are movably mounted at the bottom of the annular groove. Several evenly distributed anti-deviation keys 303 are fixedly mounted on the side of the roller cone body 3 close to the PDC drill bit 2, and the anti-deviation keys 303 are slidably mounted in the annular groove and in contact with the lubricating balls 201.

[0028] The specific implementation of this embodiment is as follows: the evenly distributed PDC drill bit 2 and roller cone body 3 ensure the efficiency of rock breaking, and each PDC drill bit 2 is installed independently so that it can be inspected or replaced individually. The installation method is stable and does not shift, which improves the overall service life. The anti-deviation key 303 on the roller cone body 3 can slide along the lubricating ball 201 in the annular groove, which provides better flexibility.

[0029] When the roller cone body 3 on the PDC drill bit 2 is working, the drive motor 10 is turned on simultaneously, which will drive the actuating block 11 to rotate. Then the actuating block 11 will move the follower shaft 12, causing the drive disc 8 to drive the vertical force rod 6 to move up and down along the guide cylinder 5. Under the elastic force of the compression spring 9, the central impact head 7 will hit the gap between each roller cone body 3 to break the rock that falls into the middle. On the one hand, this is conducive to efficient rock breaking, and on the other hand, it avoids the rock getting stuck between each roller cone, which will increase wear.

[0030] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," 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 any suitable manner in one or more embodiments or examples.

[0031] The preferred embodiments of this utility model disclosed above are merely illustrative of the present utility model. These preferred embodiments do not exhaustively describe all details, nor do they limit the utility model to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of this utility model, thereby enabling those skilled in the art to better understand and utilize it. This utility model is limited only by the claims and their full scope and equivalents.

Claims

1. A roller cone composite drill bit for rock breaking, characterized in that: The device includes a main structure (1), PDC drill bits (2), and roller cone bodies (3). Several PDC drill bits (2) arranged in a ring array are installed on the upper side of the main structure (1). Roller cone bodies (3) are movably installed on the side of each PDC drill bit (2). Two symmetrically arranged guide cylinders (5) are embedded in the top of the main structure (1). A vertical force rod (6) is slidably installed inside each guide cylinder (5). The top of the vertical force rod (6) extends to the space between each roller cone body (3) and a central impact head (7) is fixedly installed thereon. A gap is left between the central impact head (7) and the roller cone body (3).

2. A roller cone composite drill bit for rock breaking according to claim 1, characterized in that: The main structure (1) has a heat dissipation cavity installed inside, and the upper end of the heat dissipation cavity is flush with the bottom of the guide cylinder (5). The bottom end of the vertical force rod (6) extends into the heat dissipation cavity and is fixedly installed with a drive disk (8). A compression spring (9) is fixedly connected between the top of the drive disk (8) and the bottom of the guide cylinder (5), and the vertical force rod (6) passes through the compression spring (9).

3. A roller cone composite drill bit for rock breaking according to claim 2, characterized in that: A drive motor (10) is fixedly installed on the side wall of the heat dissipation cavity, and a toggle block (11) is fixedly installed on the output shaft of the drive motor (10). A follower shaft (12) is fixedly installed on the front of the drive disk (8). The toggle block (11) is located below the two follower shafts (12), and the length of the toggle block (11) is greater than the distance between the two follower shafts (12).

4. A roller cone composite drill bit for rock breaking according to claim 1, characterized in that: An isosceles trapezoidal key (101) is fixedly installed on the upper side of the main structure (1). The PDC drill bit (2) has a positioning port (202) on the side close to the main structure (1), and the isosceles trapezoidal key (101) is inserted into the positioning port (202). The PDC drill bit (2) is fixedly installed on the main structure (1) by a reinforcing bolt (203).

5. A roller cone composite drill bit for rock breaking according to claim 1, characterized in that: The roller cone body (3) is fixedly mounted with evenly distributed cutting teeth (302), and the cutting teeth (302) face away from the PDC drill bit (2). The roller cone body (3) is fixedly mounted with a central shaft (301) on the side close to the PDC drill bit (2), and the central shaft (301) is movably mounted inside the PDC drill bit (2). The PDC drill bit (2) has an annular groove, and a number of evenly distributed lubricating balls (201) are movably mounted at the bottom of the annular groove. The roller cone body (3) is fixedly mounted with a number of evenly distributed anti-deviation keys (303) on the side close to the PDC drill bit (2), and the anti-deviation keys (303) are slidably mounted in the annular groove and in contact with the lubricating balls (201).

6. A roller cone composite drill bit for rock breaking according to claim 1, characterized in that: The bottom of the main structure (1) is movably fitted with an installation joint (4).

Images