Petal cardan shaft and drilling tool comprising same

Abstract

The utility model discloses a petal cardan shaft and a drilling tool comprising the petal cardan shaft, which belong to the technical field of well drilling, the petal cardan shaft comprises a first joint, a second joint and a connecting block, the connecting block and the first joint as well as the connecting block and the second joint are in sliding fit through a sliding block and a sliding chute, and the section of the sliding block is in the shape of a ball head. The section of the sliding groove is in a ball socket shape, and the extending directions of the multiple sliding blocks are different. According to the universal shaft, the overall length of the universal shaft can be greatly shortened, the length of a drill rod can be greatly shortened when the universal shaft is used in the drill rod, centrifugal force and inertia force generated in the rotating process of the universal shaft are greatly reduced, and a drill bit is more stable in the drilling process and facilitates deflecting.

Description

Technical Field

[0001] This utility model belongs to the field of drilling technology, specifically, it relates to a petal universal joint and a drilling tool including the petal universal joint. Background Technology

[0002] The universal joint in drilling tools is an important mechanical component, mainly used to transmit torque and rotational motion, while allowing a certain angle of deflection. It plays a key role in drilling equipment (such as oil drilling rigs and geological drilling equipment), and can adapt to the deflection and vibration requirements of drilling tools under complex working conditions.

[0003] Currently, commonly used universal joints in drilling tools include cross universal joints, ball joint universal joints, petal universal joints, and flexible universal joints. When the drive unit rotates, torque is transmitted to the drive shaft through the universal joint. Among them, cross universal joints, ball joint universal joints, and petal universal joints allow the universal joint to deflect within a certain angle range, thereby adapting to the deflection requirements of the drilling tool. Finally, the torque is transmitted to the drill bit through the drive shaft, thereby driving the drill bit to rotate and complete the drilling operation.

[0004] However, in the drilling process, in order to improve drilling efficiency, control the wellbore trajectory, and cope with complex formation conditions, short rotary screws (also known as downhole screw motors or mud motors) are often used. However, in short rotary screws, the overall length of the existing universal joint is relatively long, which results in greater centrifugal force and inertial force during transmission. This causes greater vibration of the drill pipe during drilling, which is not only detrimental to stable drilling but also to directional drilling. At the same time, it restricts the downhole service life of the rotary instrument and signal transmission.

[0005] Therefore, there is an urgent need for a universal joint and drilling tool that can minimize their length. Utility Model Content

[0006] The purpose of this utility model is to provide a petal-shaped universal joint and a drill bit containing the petal-shaped universal joint, which not only greatly shortens the overall length of the universal joint, but also greatly shortens the length of the drill rod when the universal joint is used in the drill rod. This greatly reduces the centrifugal force and inertial force generated by the universal joint during rotation, making the drill bit more stable during drilling and facilitating directional drilling.

[0007] To achieve the purpose of this utility model, the technical solution adopted is as follows: a petal universal joint, including a first joint, a second joint and a connecting block. The connecting block and the first joint, and the connecting block and the second joint are slidably engaged by a slider and a groove. The cross-section of the slider is spherical and the cross-section of the groove is spherical. The extension directions of the multiple sliders are different.

[0008] Furthermore, there are multiple connecting blocks, and adjacent connecting blocks are slidably engaged by a slider and a groove. The cross-section of the slider is spherical, and the cross-section of the groove is spherical. The multiple sliders extend in different directions.

[0009] Furthermore, the included angles between the plurality of sliders are equal.

[0010] Furthermore, the slider connecting the connecting block and the first connector is located on the first connector, and the slider connecting the connecting block and the second connector is located on the second connector.

[0011] Furthermore, the slider is connected to the first connector and the second connector through an arc-shaped concave surface.

[0012] Furthermore, a water cap is connected to the first or second connector.

[0013] Furthermore, a water eye is provided on the first or second connector, one end of which penetrates the circumferential surface of the first or second connector, and the other end of which penetrates the outer end face of the first or second connector.

[0014] A drilling tool comprising a petal-shaped universal joint as described in any of the above.

[0015] The beneficial effects of this utility model are:

[0016] This invention not only significantly shortens the overall length of the universal joint, saving installation space, but also enhances its rigidity. Furthermore, it greatly reduces the centrifugal and inertial forces generated during rotation, resulting in smoother drilling and improved drill bit response speed and control precision. This facilitates more precise control of the drilling direction and trajectory, improves signal transmission for rotary steerable drilling instruments, and extends the instrument's lifespan downhole.

[0017] In this invention, by setting the cross-section of the slider to be spherical and the cross-section of the groove to be spherical, it is possible to ensure that the first connector and the connecting block swing relative to each other and the connecting block and the second connector swing relative to each other, while effectively preventing the first connector and the connecting block and the connecting block and the second connector from separating. Attached Figure Description

[0018] The accompanying drawings illustrate exemplary embodiments of the present invention and, together with the description thereof, serve to explain the principles of the present invention. These drawings are included to provide a further understanding of the present invention and are incorporated in and constitute a part of this specification.

[0019] Figure 1 This is a structural diagram of the universal joint provided by this utility model;

[0020] Figure 2 This is a structural diagram of the first connector;

[0021] Figure 3 This is a structural diagram of the second connector;

[0022] Figure 4 This is a structural diagram of the connecting block.

[0023] The attached diagram shows the markings and corresponding component names:

[0024] 1. First connector; 2. Second connector; 3. Connecting block;

[0025] 1-1, slider; 1-2, curved concave surface; 1-3, water eye;

[0026] 3-1. Slide groove. Detailed Implementation

[0027] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the scope of the present invention. Furthermore, it should be noted that, for ease of description, only the parts relevant to the present invention are shown in the accompanying drawings.

[0028] It should be noted that, where there is no conflict, the embodiments and features described in these embodiments can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0029] like Figures 1 to 4 As shown, the present invention provides a petal-shaped universal joint, including a first connector 1, a second connector 2, and a connecting block 3. The connecting block 3 is located between the first connector 1 and the second connector 2. The connecting block 3 is connected to the first connector 1 by a sliding block 1-1 and a sliding groove 3-1. The connecting block 3 is also connected to the second connector 2 by a sliding block 1-1 and a sliding groove 3-1. This allows the connecting block 3 to slide relative to the first connector 1 through the sliding block 1-1 and the sliding groove 3-1, and the connecting block 3 to the second connector 2 to slide relative to each other through the sliding block 1-1 and the sliding groove 3-1.

[0030] Meanwhile, the cross-section of slider 1-1 is spherical, and the cross-section of groove 3-1 is spherical. When the first connector 1, connecting block 3, and second connector 2 are assembled together, slider 1-1 is installed in groove 3-1, and there is a clearance fit between slider 1-1 and groove 3-1. By setting the cross-section of slider 1-1 to be spherical and the cross-section of groove 3-1 to be spherical, relative sliding and relative oscillation can occur between the first connector 1 and connecting block 3, and between connecting block 3 and second connector 2, thus facilitating directional drilling when the universal joint is used in drilling tools.

[0031] In this invention, to prevent the universal joint from swinging only in one direction, the two sliders 1-1 and the groove 3-1, which are used to connect the first connector 1 and the connecting block 3 and the second connector 2, extend in different directions. At the same time, the central axis of the slider 1-1 and the central axis of the groove 3-1 are aligned with the diameter direction of the first connector 1, the connecting block 3, or the second connector 2.

[0032] When the universal joint rotates, the centrifugal force it experiences during rotation causes radial displacement between the first joint 1 and the connecting block 3, and between the connecting block 3 and the second joint 2. This also causes relative oscillation between the first joint 1 and the connecting block 3, and between the connecting block 3 and the second joint 2. This significantly reduces the centrifugal force and inertial force generated during the rotational transmission process, ultimately allowing the rotational force to be transmitted to the drill bit. This results in a smoother drilling process, improving the drill bit's response speed and control precision, and facilitating more accurate control of the drilling direction and trajectory. Furthermore, these improvements eliminate the need for ball joint structures at both ends of the universal joint, greatly shortening its overall length. This not only saves installation space but also enhances the universal joint's rigidity.

[0033] In this invention, to meet the usage requirements of the universal joint, multiple connecting blocks 3 can be located between the first connector 1 and the second connector 2. In this case, the connection between two adjacent connecting blocks 3 is achieved through the cooperation of slider 1-1 and groove 3-1. Simultaneously, the cross-section of slider 1-1 connecting two connecting blocks 3 is spherical, and the cross-section of groove 3-1 connecting two connecting blocks 3 is spherical-socket shaped. Furthermore, the axial direction of slider 1-1 and the axial direction of groove 3-1 are both consistent with the diameter direction of connecting block 3. That is, the connection methods between two adjacent connecting blocks 3, between the first connector 1 and connecting block 3, and between connecting block 3 and second connector 2 are all the same. When the connection between two adjacent connecting blocks 3 is also achieved through the cooperation of slider 1-1 and groove 3-1, the extension directions of multiple sliders 1-1 in the entire universal joint are different, allowing the universal joint to swing in multiple directions, thus increasing the number of swing directions.

[0034] In order to make the swing direction distribution of the universal joint more uniform, the included angles between multiple sliders 1-1 in the entire universal joint are equal. It should be noted that when there is one connecting block 3, there are two sliders 1-1 in the entire universal joint: one for connecting the first connector 1 to the connecting block 3, and the other for connecting the connecting block 3 to the second connector 2. In this case, the two sliders 1-1 are arranged in a cross shape. When there are two connecting blocks 3, there are three sliders 1-1 in the entire universal joint: one for connecting the first connector 1 to the connecting block 3, one for connecting two connecting blocks 3, and one for connecting the connecting block 3 to the second connector 2. In this case, the included angle between two adjacent sliders 1-1 is 60°. When there are N connecting blocks 3, there are N+1 sliders 1-1 in the entire universal joint: one for connecting the first connector 1 to the connecting block 3, one for connecting two adjacent connecting blocks 3, and one for connecting the connecting block 3 to the second connector 2. In this case, the included angle between two adjacent sliders 1-1 is 180° / N+1.

[0035] In this invention, the slider 1-1 for connecting the first connector 1 and the connecting block 3 is located on the first connector 1, and the slider 1-1 for connecting the second connector 2 and the connecting block 3 is located on the second connector 2; alternatively, the slider 1-1 for connecting the first connector 1 and the connecting block 3 can be located on the connecting block 3, and the slider 1-1 for connecting the second connector 2 and the connecting block 3 can be located on the second connector 2; alternatively, the slider 1-1 for connecting the first connector 1 and the connecting block 3 can be located on the first connector 1, and the slider 1-1 for connecting the second connector 2 and the connecting block 3 can be located on the connecting block 3; alternatively, both the slider 1-1 for connecting the first connector 1 and the connecting block 3, and the slider 1-1 for connecting the second connector 2 and the connecting block 3, can be located on the connecting block 3. That is, as long as the first connector 1 and the connecting block 3 can swing and slide relative to each other, the slider 1-1 can be located on either the first connector 1 or the connecting block 3; as long as the second connector 2 and the connecting block 3 can swing and slide relative to each other, the slider 1-1 can be located on either the second connector 2 or the connecting block 3.

[0036] In this invention, to ensure relative swing between the first connector 1 and the connecting block 3, and relative swing between the connecting block 3 and the second connector 2, when the slider 1-1 is mounted on the first connector 1 and the second connector 2, both sides of the slider 1-1 are connected to the end faces of the first connector 1 and the second connector 2 using arc-shaped concave surfaces 1-2; when the slider 1-1 is mounted on the connecting block 3, both sides of the slider 1-1 are connected to the end faces of the connecting block 3 using arc-shaped concave surfaces 1-2. With this design, the width of the slider 1-1 near the first connector 1, the connecting block 3, and the second connector 2 is less than the maximum width at the top of the slider 1-1. This not only allows for sufficient relative swing between the first connector 1 and the connecting block 3, and between the connecting block 3 and the second connector 2, but also effectively prevents separation between the first connector 1 and the connecting block 3, and between the connecting block 3 and the second connector 2.

[0037] In this utility model, in order to cooperate with the use of the universal joint, a water cap can be threaded onto the first connector 1 or the second connector 2.

[0038] In this invention, to simplify the structure when the universal joint is used in the drill pipe, the water inlet 1-3 on the existing drill pipe water cap can be directly opened on the first connector 1 or the second connector 2. In this case, the inlet end of the water inlet 1-3 penetrates the circumferential surface of the first connector 1 or the circumferential surface of the second connector 2, and the outlet end of the water inlet 1-3 penetrates the outer end face of the first connector 1 or the outer end face of the second connector 2. It should be noted that the outer end face of the first connector 1 refers to the end face of the first connector 1 away from the connecting block 3, and the outer end face of the second connector 2 refers to the end face of the second connector 2 away from the connecting block 3. When the inlet end of the water inlet 1-3 penetrates the circumferential surface of the first connector 1 or the circumferential surface of the second connector 2, there can be multiple inlet ends of the water inlet 1-3, which can be evenly spaced along the circumferential surface of the first connector 1 or the circumferential surface of the second connector 2.

[0039] This embodiment also provides a drill bit, which includes the petal universal joint as described above.

[0040] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0041] Those skilled in the art should understand that the above embodiments are merely for clearly illustrating the present invention and are not intended to limit the scope of the present invention. Those skilled in the art can make other changes or modifications based on the above disclosure, and these changes or modifications still fall within the scope of the present invention.

Claims

1. A petal-shaped universal joint, characterized in that, It includes a first connector (1), a second connector (2) and a connecting block (3). The connecting block (3) and the first connector (1) are slidably engaged by a slider (1-1) and a groove (3-1). The cross-section of the slider (1-1) is spherical and the cross-section of the groove (3-1) is spherical. The extension directions of the multiple sliders (1-1) are different.

2. The petal-shaped universal joint according to claim 1, characterized in that, There are multiple connecting blocks (3). Two adjacent connecting blocks (3) slide and engage with each other by means of sliders (1-1) and grooves (3-1). The cross-section of slider (1-1) is spherical and the cross-section of groove (3-1) is spherical. The multiple sliders (1-1) extend in different directions.

3. The petal-shaped universal joint according to claim 1 or 2, characterized in that, The included angles between the plurality of sliders (1-1) are equal.

4. The petal-shaped universal joint according to claim 1 or 2, characterized in that, The slider (1-1) connecting the connecting block (3) and the first connector (1) is located on the first connector (1), and the slider (1-1) connecting the connecting block (3) and the second connector (2) is located on the second connector (2).

5. The petal-shaped universal joint according to claim 1 or 2, characterized in that, The slider (1-1) is connected to the first connector (1) and the slider (1-1) is connected to the second connector (2) through an arc-shaped concave surface (1-2).

6. The universal joint according to claim 1 or 2, characterized in that, A water cap is connected to the first connector (1) or the second connector (2).

7. The petal-shaped universal joint according to claim 1 or 2, characterized in that, A water eye (1-3) is provided on the first connector (1) or the second connector (2). One end of the water eye (1-3) penetrates the circumferential surface of the first connector (1) or the second connector (2), and the other end of the water eye (1-3) penetrates the outer end face of the first connector (1) or the second connector (2).

8. A drilling tool, characterized in that, Including the petal-shaped universal joint as described in any one of claims 1 to 7.

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