Roller cone and cutting tooth mixed type drill bit

Abstract

The utility model relates to a cone and cutting pick hybrid drill bit, two cutting pick blades are symmetrically distributed on a drill bit body, cutting picks are installed on each cutting pick blade, the cutting picks on the two cutting pick blades are distributed in a staggered mode in the diameter direction, two cone palm pieces are symmetrically arranged, each cone palm piece comprises a cone palm and a cone located on the cone palm, the cone palm is connected with the drill bit body, and the cone palm is connected with the drill bit body. The circumferential cutting tracks of the cone hard alloy teeth on the cone coincide with the cutting tracks of the cutting teeth on the cutting tooth blades, on the same cutting annular belt, the tooth crest contour formed by the tooth crests of the cutting teeth is parallel to the tooth crest contour formed by the cone hard alloy teeth, and the tooth crest contour of the cone hard alloy teeth is higher than the tooth crest contour of the cutting teeth. The problems of tooth breakage and blade breakage when a cutting tooth type drill bit encounters hard rocks are effectively solved, the application range of the drill bit is remarkably widened, and the drilling footage and the drilling efficiency are improved.

Description

Technical Field

[0001] The utility model relates to a novel hybrid drill bit, in particular to a cone and pick hybrid drill bit, belonging to the technical field of rock drilling tools. Background Art

[0002] Both pick drill bits and roller cone drill bits are common rock drilling tools, widely used in engineering construction, mining, and oil drilling. Currently, roller cone drill bits are primarily tri-cone drill bits. These bits crush and impact rock using carbide teeth embedded in the cones. They are primarily used in soft, medium-hard, and hard formations with a hardness greater than F1.5. Pick drill bits typically feature picks mounted on a drill bit body. These cutters scrape and shear the rock. Due to the material properties and operating mode of the picks, they are primarily used in soft and extremely soft formations with a hardness less than F1.5, typically soft and extremely soft coal seams, sandstone, and highly weathered rock formations.

[0003] Currently, the fields of engineering construction, rock breaking in mining, and oil drilling are placing increasingly higher demands on drill bit footage and drilling efficiency. The drilling efficiency of roller cone drill bits in extremely soft formations is limited, and it is difficult to significantly increase the footage. This increases the overall drilling cost, and the product has no cost-effectiveness advantage. Pick-type drill bits can achieve relatively good drilling rig efficiency and footage when drilling in extremely soft formations, effectively controlling the overall cost of the drill bit. However, in actual use, many formations have uneven hardness and softness, and some hard interlayers and hard rock exist in extremely soft formations. This can easily lead to early breakage of the picks on pick-type drill bits, or even breakage of the blades, leading to early failure of the drill bit. Therefore, addressing the early failure of pick-type drill bits in uneven formations such as soft and hard interlayers and expanding their scope of application are currently urgent issues to be addressed. Utility Model Content

[0004] The utility model aims to provide a cone and pick hybrid drill bit to solve the problem of early failure caused by broken teeth and blades when existing pick drill bits operate in extremely soft and soft formations with some hard interlayers and hard rocks.

[0005] The purpose of this utility model is achieved through the following technical solutions:

[0006] The hybrid drill bit of cone and pick is characterized by: two pick blades are symmetrically distributed on the drill bit body, each pick blade is equipped with a pick, the picks on the two pick blades are staggered in the diameter direction, the two cone palms are symmetrically arranged, the cone palm includes a tooth palm and a cone located thereon, the tooth palm is connected to the drill bit body, the circumferential cutting trajectory of the cone carbide teeth on the cone coincides with the cutting trajectory of the pick on the pick blade, on the same cutting ring, the tooth top profile formed by the pick tooth top is parallel to the tooth top profile formed by the cone carbide teeth, and the tooth top profile of the cone carbide teeth is higher than the tooth top profile of the pick.

[0007] Furthermore, in the above-mentioned cone and pick hybrid drill bit, the pick is installed on the pick blade through the pick mounting hole.

[0008] Furthermore, in the above-mentioned cone and pick hybrid drill bit, the connection between the pick palm and the drill bit body is welded or bolted.

[0009] Furthermore, in the above-mentioned cone and pick hybrid drill bit, the tooth palm is provided with a bolt adjustment hole in the vertical direction, and the drill bit body is provided with a tooth palm connecting groove for positioning the tooth palm, and the tooth palm is connected to the drill bit body by bolts.

[0010] Furthermore, in the above-mentioned cone and pick hybrid drill bit, a cone avoidance groove is processed on the drill bit body to avoid interference between the cone and the drill bit body.

[0011] Furthermore, in the above-mentioned cone and pick hybrid drill bit, the tooth top profile of the cemented carbide teeth of the cone is 1 to 3 mm higher than the tooth top profile of the pick.

[0012] Furthermore, in the above-mentioned cone and pick hybrid drill bit, the back of each pick blade and the back of the palm of the pick are inlaid with palm back cemented carbide teeth.

[0013] Furthermore, in the above-mentioned cone and pick hybrid drill bit, a central air jet hole and a side air jet hole are provided on the drill bit body, the central air jet hole forms an angle with the center line of the drill bit body; and the side air jet hole is located between the cone and the pick blade.

[0014] Furthermore, in the above-mentioned cone and pick hybrid drill bit, the cone carbide teeth are spoon-shaped, wedge-shaped, cone-ball, double-ball or ball-headed.

[0015] Compared with the prior art, the present invention has significant advantages and beneficial effects, which are specifically reflected in the following aspects:

[0016] The utility model effectively solves the problem of broken teeth and blades when a pick-type drill bit encounters hard rock. The pick blades are equipped with a corresponding number of picks, and the pick blades and the cones are spaced apart and arranged in pairs to achieve better rock breaking effect and force balance. The picks on the two pick blades are staggered in diameter to form relatively complete bottom hole coverage. The cone part first contacts the formation, and the carbide teeth pre-crush the rock, especially hard rock, causing microcracks or broken pits in the rock. The picks then contact the formation and scrape the pre-crushed rock to completely cut the rock. This significantly improves the application range of the drill bit, increases footage and drilling efficiency. At the same time, the cutting parts are all replaceable parts, which greatly reduces the overall cost of the drill bit.

[0017] Other features and advantages of the present invention will be described in the following description, and in part will become apparent from the description, or understood by practicing the specific embodiments of the present invention. The purposes and other advantages of the present invention can be achieved and obtained by the structures particularly pointed out in the written description and the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0019] Figure 1 : An axonometric diagram of the drill bit of the utility model;

[0020] Figure 2 : Another axonometric diagram of the drill bit of the utility model;

[0021] Figure 3 : Schematic diagram of the structure of the gear palm;

[0022] Figure 4 : Schematic diagram of the structure of the drill bit body;

[0023] Figure 5 : Schematic diagram of the connection between the tooth palm and the drill body;

[0024] Figure 6 : Schematic diagram of the decomposition of the tooth palm and the drill body. DETAILED DESCRIPTION

[0025] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. The components of the embodiments of the present invention generally described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the utility model for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative work are within the scope of protection of the present invention.

[0026] It should be noted that similar reference numerals and letters represent similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings. At the same time, in the description of this utility model, directional terms and order terms are only used to distinguish the description and should not be understood as indicating or implying relative importance.

[0027] like Figures 1 to 4 As shown, a hybrid drill bit of a roller and pick comprises a drill body 1, a pick blade 2 and a roller palm piece 6. The pick blade and the roller are spaced apart and arranged in pairs. Two pick blades 2 are symmetrically distributed on the drill body 1. Each pick blade is equipped with a plurality of picks 3. The picks 3 are fixed on the pick blade 2 through the pick mounting holes. The picks on the two pick blades are staggered in the diameter direction to form a relatively complete bottom hole coverage. The two roller palm pieces 6 are symmetrically arranged. The roller palm piece 6 comprises a tooth palm 4 and a roller 5 located thereon. The tooth palm 4 is fixed to the roller 5. The drill bit body 1 is connected. The carbide teeth 7 on the cutter 1 adopt different tooth shapes such as spoon-shaped, wedge-shaped, cone-ball, double-ball, and ball-head (applicable to formations ranging from soft to hard) to adapt to different formations. The circumferential cutting trajectory of the carbide teeth 7 coincides with the cutting trajectory of the pick 3 on the pick blade. On the same cutting ring, the top profile formed by the top of the pick 3 is parallel to the top profile formed by the carbide teeth 7, both of which form a smooth curve. The top profile of the carbide teeth 7 is 1 to 3 mm higher than the top profile of the pick 3. The drill bit body 1 is machined with a cutter avoidance groove 12 to prevent interference between the cutter 5 and the drill bit body 1. Several carbide teeth 8 are embedded on the back of each pick blade 2 and the back of the palm 4.

[0028] like Figure 2 The drill bit body 1 is equipped with a central jet hole 9 and side jet holes 10. Compressed air from the drill pipe to the drill bit's slurry hole is sprayed toward the bottom of the hole through the jet holes, effectively cleaning the bottom rock debris. The central jet hole 9 forms an angle with the centerline of the drill bit body 1 and is located near the center of the hole bottom. There is one central jet hole 9, and the jet hole forms a ring during the jet process, effectively preventing the formation of a rock column at the center of the drill bit. The side jet holes 10 are located between the cone 5 and the pick blade 2, and the jet hole is located near the bottom and wall of the hole. There are four side jet holes 10, which not only clean the bottom rock debris, but also clean the cone 5 and pick 3, preventing the formation of mud balls.

[0029] like Figures 5-6The connection between the palm 4 and the drill bit body 1 is either welded or bolted. The bolted connection is designed to be height-adjustable. The palm 4 is provided with bolt adjustment holes 15 along the vertical direction of the palm back. The drill bit body 1 is provided with palm connection grooves 13 for positioning the palm 4. The palm 4 is connected to the drill bit body 1 via bolts 14, which are screwed into threaded holes in the drill bit body 1. When the proportion of hard formations in the ground is high, the height of the cone can be adjusted higher along the V-axis. When the proportion of hard formations is low, the height of the cone can be adjusted lower along the V-axis.

[0030] The cutting part of the drill bit consists of two pick blades equipped with a certain number of picks and two cones. The parts used for cutting are the picks and the carbide teeth of the cones. The pick blades are equipped with a corresponding number of picks, and the pick blades and the cones are spaced in pairs to achieve better rock breaking effect and force balance. The picks on the two pick blades are staggered in diameter to form relatively complete bottom hole coverage. The picks on the pick blades are detachable mounting structures, and the cone palm can also be a detachable mounting structure. During use, if the drill bit body has not been completely damaged, the damaged cutting parts (single pick or cone palm) can be replaced to save the overall cost of the drill bit. The connection between the cone palm and the drill bit body can be set to welding and bolt connection. The welding type has better bonding strength, and the bolt connection can achieve quick replacement.

[0031] During operation, the cone 5 first contacts the ground, where the carbide teeth 7 pre-crush the rock, especially hard rock, creating microcracks or crushing pits. The pick 3 then contacts the ground and scrapes the pre-crushed rock to completely crush it. A number of carbide teeth 8 are embedded on the back of each pick blade 2 and the back of the palm 4, protecting the blades and palm and assisting in maintaining the gage.

[0032] In summary, the present invention effectively solves the problem of broken teeth and blades when a pick-type drill bit encounters hard rock. A corresponding number of picks are installed on the pick blades, and the pick blades and the cones are spaced apart and arranged in pairs to achieve better rock breaking effect and force balance; the picks on the two pick blades are staggered in diameter to form relatively complete bottom hole coverage; the cone part first contacts the formation, and the carbide teeth pre-crush the rock, especially the hard rock, causing microcracks or broken pits in the rock. The picks then contact the formation and scrape the pre-crushed rock to completely cut the rock. This significantly improves the application range of the drill bit, and increases footage and drilling efficiency; at the same time, the cutting parts are all replaceable parts, which greatly reduces the overall cost of the drill bit.

[0033] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, improvements, and the like made within the spirit and principles of the present invention are intended to be included within the scope of protection of the present invention. It should be noted that similar reference numerals and letters denote similar items in the following figures. Therefore, once an item is defined in one figure, it need not be further defined or explained in subsequent figures.

[0034] The above is only a specific implementation method of the present invention, but the protection scope of the present invention is not limited to this. Any technician familiar with this technical field can easily think of changes or replacements within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

[0035] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply the existence of any such actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article, or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or device comprising the element.

Claims

1. A hybrid drill bit with cones and picks, characterized by: Two pick blades (2) are symmetrically distributed on a drill bit body (1), each pick blade is equipped with a pick (3), the picks on the two pick blades are staggered in the diameter direction, two cone palms (6) are symmetrically arranged, the cone palm (6) comprises a tooth palm (4) and a cone (5) located thereon, the tooth palm (4) is connected to the drill bit body (1), the circumferential cutting trajectory of the cone carbide teeth (7) on the cone (1) coincides with the cutting trajectory of the pick (3) on the pick blade, on the same cutting ring, the tooth top profile formed by the tooth top of the pick (3) is parallel to the tooth top profile formed by the cone carbide teeth (7), and the tooth top profile of the cone carbide teeth (7) is higher than the tooth top profile of the pick (3).

2. The cone and pick hybrid drill bit according to claim 1, characterized in that: The pick (3) is mounted on the pick blade (2) through the pick mounting hole.

3. The cone-cutting cutter hybrid drill bit according to claim 1, characterized in that: The connection between the tooth palm (4) and the drill body (1) is a welding type or a bolt connection type.

4. The cone-cutting cutter hybrid drill bit according to claim 3, characterized in that: The tooth palm (4) is provided with a bolt adjustment hole (15) in the vertical direction, and the drill bit body (1) is provided with a tooth palm connecting groove (13) for positioning the tooth palm (4). The tooth palm (4) is connected to the drill bit body (1) via a bolt (14).

5. The cone-cutting cutter hybrid drill bit according to claim 1, characterized in that: A cone avoidance groove (12) is machined on the drill bit body (1) to prevent the cone (5) from interfering with the drill bit body (1).

6. The cone-cutting cutter hybrid drill bit according to claim 1, characterized in that: The tooth top profile of the hard alloy tooth (7) of the gear is 1 to 3 mm higher than the tooth top profile of the pick (3).

7. The cone-cutting cutter hybrid drill bit according to claim 1, wherein: The back of each pick blade (2) and the back of the palm of the tooth palm (4) are both inlaid with palm back hard alloy teeth (8).

8. The cone-cutting cutter hybrid drill bit according to claim 1, wherein: A central jet hole (9) and a side jet hole (10) are provided on the drill bit body (1). The central jet hole (9) forms an angle with the center line of the drill bit body (1); and the side jet hole (10) is located between the cone (5) and the pick blade (2).

9. The cone-cutting cutter hybrid drill bit according to claim 1, wherein: The carbide teeth (7) of the gear are spoon-shaped, wedge-shaped, cone-shaped, double-ball-shaped or ball-shaped.

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