Universal shaft and drilling tool comprising same

Abstract

The utility model discloses a cardan shaft and a drilling tool comprising the cardan shaft, which belong to the technical field of well drilling, the cardan shaft comprises a first joint, a second joint and a connecting block, the connecting block is provided with a first extension part and a second extension part which are arranged in a cross extension mode, and the inner end of the first joint and the inner end of the second joint are respectively provided with a sliding groove. The two sliding grooves are in sliding fit with the first extending part and the second extending part correspondingly. 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.

Description

Technical Field

[0001] This utility model belongs to the field of drilling technology, specifically, it relates to a universal joint and a drilling tool including the 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. Cross universal joints, ball joint universal joints, and petal universal joints allow the universal joint to deflect within a certain angle range, thus adapting to the deflection requirements of the drilling tool. Ultimately, the torque is transmitted to the drill bit through the universal joint, 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 universal joint and a drill bit containing the 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, thereby greatly reducing the centrifugal force and inertial force generated by the universal joint during rotation, and making the drill bit more stable during drilling.

[0007] To achieve the purpose of this utility model, the technical solution adopted is as follows: a universal joint, including a first joint, a second joint and a connecting block, wherein the connecting block has a first extension and a second extension arranged in a cross shape, and the inner ends of the first joint and the second joint are both provided with sliding grooves, and the two sliding grooves are respectively slidably engaged with the first extension and the second extension.

[0008] Furthermore, both the inner ends of the first and second connectors have two opposing claws, with a groove formed between the two claws.

[0009] Furthermore, the claw head is L-shaped, and the sides or ends of the first extension and the second extension engage with the inner sidewall of the claw head.

[0010] Furthermore, the sides or ends of the first extension and the second extension are inclined surfaces, and the inner wall of the horizontal section of the claw head is a slope that matches the inclined surface.

[0011] Furthermore, the connecting block is cross-shaped.

[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 universal joint as described 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 response speed and control precision, facilitating more accurate control of the drilling direction and trajectory. Attached Figure Description

[0017] 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.

[0018] Figure 1 This is a structural diagram of the universal joint provided by this utility model;

[0019] Figure 2 This is a structural diagram of the first connector;

[0020] Figure 3 This is a structural diagram of the connecting block.

[0021] The attached diagram shows the markings and corresponding component names:

[0022] 1. First connector; 2. Second connector; 3. Connecting block;

[0023] 1-1. Slide groove; 1-2. Claw head; 1-3. Slope surface;

[0024] 3-1, First extension; 3-2, Second extension; 3-3, Inclined surface. Detailed Implementation

[0025] 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.

[0026] 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.

[0027] like Figure 1 As shown, the universal joint provided by this utility model includes 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, and has a first extension 3-1 and a second extension 3-2. The extension directions of the first extension 3-1 and the second extension 3-2 are arranged in a cross shape. The inner ends of the first connector 1 and the second connector 2 each have a groove 1-1. The axial direction of the groove 1-1 on the first connector 1 is arranged in a cross shape with the axial direction of the groove 1-1 on the second connector 2. However, the groove 1-1 on the first connector 1 extends along its diameter, and the groove 1-1 on the second connector 2 also extends along its diameter. The groove 1-1 on the first connector 1 is slidably engaged with the first extension 3-1, and the groove 1-1 on the second connector 2 is slidably engaged with the second extension 3-2. When the first connector 1, the second connector 2, and the connecting block 3 are assembled together, the sliding direction of the first connector 1 on the connecting block 3 is opposite to the sliding direction of the second connector 2 on the connecting block 3, forming a cross shape.

[0028] When the universal joint rotates, the centrifugal force it experiences during rotation causes radial displacement between the first joint 1 and the second joint 2. This significantly reduces the centrifugal force and inertial force generated during the rotational transmission of the universal joint. Ultimately, after the rotational force is transmitted to the drill bit, the drill bit operates more smoothly during drilling, improving the response speed and control precision of the drilling tool, and facilitating more precise control of the drilling direction and trajectory. At the same time, through the above improvements, the ball joint structure is no longer required at both ends of the universal joint, which greatly shortens the overall length of the universal joint. This not only saves installation space but also makes the universal joint more rigid.

[0029] To ensure that both the first connector 1 and the second connector 2 can slide relative to the connecting block 3, two claw heads 1-2 are provided at the inner end of the first connector 1, symmetrically arranged around its central axis. Two claw heads 1-2 are also provided at the inner end of the second connector 2, symmetrically arranged around its central axis. There is a certain distance between the two claw heads 1-2 at the inner end of the first connector 1 and between the two claw heads 1-2 at the inner end of the second connector 2, so that a sliding groove 1-1 is formed between the two claw heads 1-2 at the inner end of the first connector 1 and between the two claw heads 1-2 at the inner end of the second connector 2. The sliding groove 1-1 between the two claw heads 1-2 on the first connector 1 slides in engagement with the first extension 3-1, and the sliding groove 1-1 between the two claw heads 1-2 on the second connector 2 slides in engagement with the second extension 3-2.

[0030] In this utility model, in order to ensure that the universal joint has a more aesthetically pleasing appearance, the outer surface of the claw head 1-2 is designed to be an arc surface, which is a complete surface with the circumferential surface of the first connector 1 or the second connector 2.

[0031] In this invention, to prevent the sliding connection between the first connector 1, the second connector 2, and the connecting block 3 from detaching, the claws 1-2 on the first connector 1 and the second connector 2 are both "L"-shaped. The two ends of the first extension 3-1 respectively engage with the two claws 1-2 on the first extension 3-1, and the two ends of the second extension 3-2 respectively engage with the two claws 1-2 on the second extension 3-2. By setting the claws 1-2 to an "L" shape, the inner end of the first connector 1 can slide and engage with the end of the first extension 3-1 through the claws 1-2, and the inner end of the second connector 2 can slide and engage with the end of the second extension 3-2 through the claws 1-2. This effectively prevents the first connector 1, the second connector 2, and the connecting block 3 from detaching while ensuring relative sliding between the first connector 1 and the connecting block 3, and between the second connector 2 and the connecting block 3.

[0032] In this utility model, while ensuring that the sliding direction of the first connector 1 relative to the first extension 3-1 and the sliding direction of the second connector 2 relative to the second extension 3-2 are arranged in a cross shape, the two sides of the first extension 3-1 can respectively cooperate with the two claws 1-2 on the first extension 3-1, and the two sides of the second extension 3-2 can respectively cooperate with the two claws 1-2 on the second extension 3-2.

[0033] To simplify the structure of the connecting block 3, it can be directly designed as a cross shape. In this case, the part extending along one axis of the connecting block 3 is the first extension 3-1, and the part extending along the other axis is the second extension 3-2. Alternatively, without considering the complexity of the connecting block 3, it can also be a disc with a protrusion on each of its two planes, ensuring that the axes of the two protrusions are perpendicular to each other. In this case, the two protrusions are equivalent to the first extension 3-1 and the second extension 3-2. The two claws 1-2 on the first connector 1 slide and engage with the sides of the first extension 3-1, and the two claws 1-2 on the second connector 2 slide and engage with the sides of the second extension 3-2. This design can also meet the requirements of a universal joint.

[0034] In this invention, when the two claws 1-2 on the first connector 1 are slidably engaged with the two ends of the first extension 3-1, and the two claws 1-2 on the second connector 2 are slidably engaged with the two ends of the first extension 3-1, both ends of the first extension 3-1 and both ends of the second extension 3-2 on the connecting block 3 can be directly set as inclined surfaces 3-3. At this time, on the first connector 1, the inner wall of the horizontal section of the claw 1-2 is a slope 1-3, which engages with the inclined surfaces 3-3 at both ends of the first extension 3-1. On the second connector 2, the inner wall of the horizontal section of the claw 1-2 is also a slope 1-3, which engages with the inclined surfaces 3-3 at both ends of the second extension 3-2. It should be noted that the horizontal section of the claw 1-2 is the end of the claw 1-2 furthest from the first connector 1 or the second connector 2.

[0035] 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.

[0036] In this invention, to simplify the structure when the universal joint is used in a drill pipe, the water eye on the existing drill pipe water cap can be directly opened on the first joint 1 or the second joint 2. In this case, one end of the water eye penetrates the circumferential surface of the first joint 1 or the circumferential surface of the second joint 2, and the other end of the water eye penetrates the outer end face of the first joint 1 or the outer end face of the second joint 2. It should be noted that the outer end face of the first joint 1 refers to the end face of the first joint 1 away from the connecting block 3, and the outer end face of the second joint 2 refers to the end face of the second joint 2 away from the connecting block 3.

[0037] This embodiment also provides a drilling tool, which includes a universal joint as described above.

[0038] In the description of this specification, the references to terms such as "one embodiment / mode," "some embodiments / modes," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment / mode or example is included in at least one embodiment / mode or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment / mode or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments / modes or examples. Furthermore, without contradiction, those skilled in the art can combine and integrate the different embodiments / modes or examples described in this specification, as well as the features of different embodiments / modes or examples.

[0039] 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.

[0040] 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 universal joint, characterized in that, It includes a first connector (1), a second connector (2) and a connecting block (3). The connecting block (3) has a first extension (3-1) and a second extension (3-2) arranged in a cross shape. The inner end of the first connector (1) and the inner end of the second connector (2) both have a sliding groove (1-1). The two sliding grooves (1-1) slide with the first extension (3-1) and the second extension (3-2) respectively.

2. The universal joint according to claim 1, characterized in that, The inner ends of the first connector (1) and the second connector (2) each have two claws (1-2) arranged opposite to each other, and a groove (1-1) is formed between the two claws (1-2).

3. The universal joint according to claim 2, characterized in that, The claw head (1-2) is L-shaped, and the two sides or both ends of the first extension (3-1) and the second extension (3-2) are engaged with the inner sidewall of the claw head (1-2).

4. The universal joint according to claim 3, characterized in that, The first extension (3-1) and the second extension (3-2) have inclined surfaces (3-3) on both sides or at both ends, and the inner wall of the horizontal section of the claw head (1-2) is a slope (1-3) that matches the inclined surface (3-3).

5. The universal joint according to claim 1, characterized in that, The connecting block (3) is cross-shaped.

6. The universal joint according to any one of claims 1 to 5, characterized in that, A water cap is connected to the first connector (1) or the second connector (2).

7. The universal joint according to any one of claims 1 to 5, characterized in that, A water eye is provided on the first connector (1) or the second connector (2), one end of which penetrates the circumferential surface of the first connector (1) or the second connector (2), and the other end of which penetrates the outer end face of the first connector (1) or the second connector (2).

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

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