Hybrid inserted roller bit

Abstract

The invention belongs to the technical field of roller bits, and particularly relates to a mixed inserted roller bit which comprises a roller palm and a roller cone, the roller cone is connected with the roller palm through a shaft diameter arranged on the lower portion of the roller palm and rotates around the shaft diameter of the roller palm, and multiple rows of hard alloy teeth are arranged on the outer surface of the roller cone. And each main cutting tooth row comprises at least two hard alloy teeth with different sizes and the same type. The rock breaking efficiency and the mechanical drilling speed of the roller bit in a medium-hardness stratum can be improved, the well building period is shortened, and the well drilling cost is reduced by changing parameters such as the tooth exposure height, the tooth tip angle, the cut-in angle and the tooth crest arc of the cutting teeth of the main cutting tooth row according to the height difference generated when single and double gear flows of the roller bit make contact with the well bottom.

Description

Technical Field

[0001] The invention belongs to the technical field of roller drill bits, and in particular relates to a mixed insert roller drill bit. Background Art

[0002] The drill bit is a rock-breaking tool used to break rocks and form a wellbore during the drilling process. Currently, the most widely used rock-breaking tools are fixed-tooth cutting drill bits and non-fixed-tooth cutting drill bits. The most widely used fixed-tooth cutting drill bit is the PDC drill bit, which is a polycrystalline diamond composite drill bit; the non-fixed-tooth cutting drill bit is mainly a roller drill bit. The roller drill bit can be divided into two categories according to the type of teeth, one is the insert-tooth roller drill bit, and the other is the steel-tooth (milling-tooth) roller drill bit. Among them, the insert-tooth roller drill bit is the most widely used roller drill bit, which is suitable for formations ranging from soft to hard.

[0003] The roller bit rotates clockwise using the torque transmitted from the well by the drill string. The roller at the bottom of the drill bit rolls on the bottom of the well by friction. The teeth embedded in the roller contact the bottom of the well alternately in the form of single teeth and double teeth, respectively, so that the axis of the roller vibrates vertically up and down in the direction perpendicular to the bottom of the well. The teeth use the inertial impact force to punch pits on the bottom of the well to accumulate footage. Under current technical conditions, the teeth on the main cutting tooth row of the roller are the same regardless of the exposed tooth height, tooth tip angle, and cutting angle. The roller bit of this structure simply uses the inertial impact force generated by the height difference between the single and double teeth alternately contacting the bottom of the well to break the rock. This drill bit works well in soft and medium-soft formations, but the rock breaking efficiency and mechanical drilling speed are not high in medium-hard formations and hard formations, and it fails to give full play to its structural advantages. Summary of the invention

[0004] The object of the present invention is to provide a hybrid insert cone drill bit to solve the problems existing in the background technology.

[0005] To achieve the above-mentioned purpose, the present invention provides the following technical solution: a hybrid toothed roller drill bit, comprising a tooth palm and a roller, wherein the roller is connected to the tooth palm through an axial diameter arranged at the lower part of the tooth palm and rotates around the axial diameter of the tooth palm, and a plurality of rows of cemented carbide teeth are arranged on the outer surface of the roller, and each row of main cutting teeth on the roller contains at least two same-type cemented carbide teeth of different sizes.

[0006] The tooth shape of the cemented carbide teeth embedded on the outer surface of the gear can be ball-head teeth, cone-ball teeth, wedge-shaped teeth, spoon-shaped teeth and the like.

[0007] The main cutting tooth row may include two types of wedge-shaped teeth: wedge-shaped tooth a and wedge-shaped tooth b, wherein the difference in exposed tooth height between wedge-shaped tooth a and wedge-shaped tooth b is 0.8mm≤|H1-H2|≤1.5mm, the difference in tooth tip angle is 5°≤|α1-α2|≤10°, and the difference in cutting angle is 3°≤|β1-β2|≤5°.

[0008] As a preferred embodiment, the main cutting tooth row may include two types of spoon-shaped teeth: spoon-shaped tooth a and spoon-shaped tooth b, wherein the difference in exposed tooth height between spoon-shaped tooth a and spoon-shaped tooth b is 0.8mm≤|H3-H4|≤1.5mm, and the difference in tooth tip angle is 5°≤|α3-α4|≤10°.

[0009] As a preferred solution, the main cutting tooth row may include two types of conical ball teeth: conical ball teeth a and conical ball teeth b, wherein the difference in tooth exposed height between conical ball teeth a and conical ball teeth b is 1mm≤|H5-H6|≤2mm, and the tooth top arc is 0.5mm≤|R1-R2|≤1mm.

[0010] As a preferred solution, the main cutting tooth row includes two types of ball-head teeth: ball-head teeth a and ball-head teeth b, wherein the difference in tooth exposure height between ball-head teeth a and ball-head teeth b is 1mm≤|H7-H8|≤2mm.

[0011] The wedge-shaped teeth a and wedge-shaped teeth b, spoon-shaped teeth a and spoon-shaped teeth b, cone-shaped ball teeth a and cone-shaped ball teeth b, and ball-head teeth a and ball-head teeth b in the above-mentioned scheme are arranged circumferentially in the main cutting tooth row in groups of two.

[0012] Compared with the prior art, the present invention has the following beneficial effects: utilizing the height difference caused by the contact between the single and double gears of the roller drill bit and the bottom of the well, by changing the parameters such as the exposed tooth height, tooth tip angle, cutting angle and tooth top arc of the cutting teeth of the main cutting tooth row, the rock breaking efficiency and mechanical drilling speed of the roller drill bit in medium hardness formations can be improved, the well construction period can be shortened, and the drilling cost can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic diagram of the structure of a hybrid tooth roller drill bit;

[0014] Figure 2 It is a schematic diagram of the palm structure of a hybrid insert drill bit;

[0015] Figure 3 It is a schematic diagram of the structure of the cone assembly of a hybrid insert toothed cone drill bit;

[0016] Figure 4 It is a schematic diagram of the wedge-shaped gear structure;

[0017] Figure 5 It is a schematic diagram of the spoon-shaped tooth structure;

[0018] Figure 6 It is a schematic diagram of the cone ball gear structure;

[0019] Figure 7 It is a schematic diagram of the ball head gear structure;

[0020] Explanation of reference numerals: 1, tooth palm, 2, cone, 3, tooth palm axis diameter, 4, thread, 5, cone main cutting tooth row

[0021] H1, wedge-shaped tooth a, high exposed teeth, H2, wedge-shaped tooth b, high exposed teeth, H3, spoon-shaped tooth a, high exposed teeth, H4, wedge-shaped tooth b, high exposed teeth, H5, cone-shaped tooth a, high exposed teeth, H6, cone-shaped tooth b, high exposed teeth, H7, ball-shaped tooth a, high exposed teeth, H8, ball-shaped tooth b, high exposed teeth

[0022] α1, wedge-shaped tooth a tooth tip angle, α2, wedge-shaped tooth b tooth tip angle, α3, spoon-shaped tooth a tooth tip angle, α4, spoon-shaped tooth b tooth tip angle. DETAILED DESCRIPTION

[0023] The present invention will be further described below in conjunction with specific embodiments and drawings.

[0024] Implementation Cases

[0025] like Figures 1 to 7 As shown, a hybrid toothed roller drill bit comprises a tooth palm 1 and a roller 2, wherein the roller 2 is connected to the tooth palm 1 through an axial diameter 3 arranged at the lower part of the tooth palm 1 and rotates around the tooth palm axial diameter 3, and a plurality of rows of cemented carbide teeth are arranged on the outer surface of the roller. A tooth palm 1 and a roller 2 form a tooth palm unit, and three tooth palm units form a roller drill bit by welding, and are connected to the drill tool through a thread 4 at the rear of the drill bit. As an option of the present invention, two types of cemented carbide teeth are arranged on the main cutting tooth row 5 of the roller 2: wedge-shaped teeth a and wedge-shaped teeth b, ensuring that the difference in tooth height between the wedge-shaped teeth a and the wedge-shaped teeth b is 0.8mm≤|H1-H2|≤1.5mm, the difference in tooth tip angle is 5°≤|α1-α2|≤10°, and the difference in cutting angle is 3°≤|β1-β2|≤5°. The wedge-shaped teeth a and the wedge-shaped teeth b can be arranged circumferentially on the main cutting tooth row in groups of two.

[0026] As another option of the present invention, two types of cemented carbide teeth are arranged on the main cutting tooth row 5 of the cone 2: spoon-shaped teeth a and spoon-shaped teeth b, and the difference in tooth height between spoon-shaped teeth a and spoon-shaped teeth b is ensured to be 0.8 mm ≤ |H3-H4| ≤ 1.5 mm, and the difference in tooth tip angle is 5° ≤ |α3-α4| ≤ 10°. Spoon-shaped teeth a and spoon-shaped teeth b can be arranged circumferentially on the main cutting tooth row in groups of two.

[0027] As another option of the present invention, two types of cemented carbide teeth are arranged on the main cutting tooth row 5 of the cone 2: cone ball teeth a and cone ball teeth b, and the difference in tooth height between cone ball teeth a and cone ball teeth b is ensured to be 1mm≤|H5-H6|≤2mm, and the tooth top arc is 0.5mm≤|R1-R2|≤1mm. Cone ball teeth a and cone ball teeth b can be arranged circumferentially on the main cutting tooth row in groups of two.

[0028] As another option of the present invention, two types of cemented carbide teeth are arranged on the main cutting tooth row 5 of the cone 2: ball head teeth a and ball head teeth b, and the difference in tooth height between the ball head teeth a and the ball head teeth b is ensured to be 1mm≤|H7-H8|≤2mm. The ball head teeth a and the ball head teeth b can be arranged circumferentially on the main cutting tooth row in groups of two.

[0029] The combination of alloy teeth a and alloy teeth b stated above is only the most commonly used arrangement and combination. There are other similar combinations: for example, 2 alloy teeth a and 1 alloy b or 1 alloy tooth a and 2 alloy teeth b, etc. There are many combinations and they will not be explained one by one here.

[0030] The above descriptions are only a few examples of the present invention and do not limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.

[0031] It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention, and these improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A hybrid insert roller drill bit, comprising a tooth palm and a roller, wherein the roller is connected to the tooth palm through an axial diameter arranged at the lower part of the tooth palm and rotates around the axial diameter of the tooth palm, and a plurality of rows of cemented carbide teeth are arranged on the outer surface of the roller, characterized in that: Each row of main cutting teeth includes at least two same-type cemented carbide teeth of different sizes.

2. The hybrid insert cone drill bit according to claim 1, characterized in that: The tooth shape of the cemented carbide tooth is a ball head tooth, a cone ball tooth, a wedge-shaped tooth or a spoon-shaped tooth.

3. The hybrid insert cone drill bit according to claim 1, characterized in that: The main cutting tooth row includes two types of wedge-shaped teeth: wedge-shaped tooth a and wedge-shaped tooth b, wherein the difference in exposed tooth height between wedge-shaped tooth a and wedge-shaped tooth b is 0.8mm≤|H1-H2|≤1.5mm, the difference in tooth tip angle is 5°≤|α1-α2|≤10°, and the difference in cutting angle is 3°≤|β1-β2|≤5°.

4. The hybrid insert cone drill bit according to claim 1, characterized in that: The main cutting tooth row includes two types of spoon-shaped teeth: spoon-shaped tooth a and spoon-shaped tooth b, wherein the difference in tooth exposed height between spoon-shaped tooth a and spoon-shaped tooth b is 0.8mm≤|H3-H4|≤1.5mm, and the difference in tooth tip angle is 5°≤|α3-α4|≤10°.

5. The hybrid insert cone drill bit according to claim 1, characterized in that: The main cutting tooth row includes two types of cone ball teeth: cone ball teeth a and cone ball teeth b, wherein the difference in tooth exposed height between cone ball teeth a and cone ball teeth b is 1mm≤|H5-H6|≤2mm, and the tooth top arc is 0.5mm≤|R1-R2|≤1mm.

6. The hybrid insert cone drill bit according to claim 1, characterized in that: The main cutting tooth row includes two types of ball head teeth: ball head tooth a and ball head tooth b, wherein the difference between the exposed tooth heights of the ball head tooth a and the ball head tooth b is 1mm≤|H7-H8|≤2mm.

7. The hybrid insert roller drill bit according to claim 1, characterized in that: Wedge-shaped teeth a and wedge-shaped teeth b, spoon-shaped teeth a and spoon-shaped teeth b, cone-shaped ball teeth a and cone-shaped ball teeth b, and ball-head teeth a and ball-head teeth b are arranged in the main cutting tooth row in a group of two in a circumferential direction.

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