Centralizer device with composite functions of self-rotating cleaning and resistance reduction

Abstract

The embodiment of the invention provides a centralizer device with self-rotation cleaning and resistance reduction composite functions, and relates to the field of petroleum drilling and geological exploration. Comprising a connector pipeline, a fluid pipeline, an upper centralizing fin assembly, an upper bearing assembly, a rotational flow centralizing device, a lower bearing assembly, a lower centralizing fin assembly and a drill bit connector. The bottom of the joint pipeline is fixedly connected with a fluid pipeline; the upper centralizing fin assembly is fixedly installed on the outer side of the fluid pipeline and installed below the connector pipeline. An upper bearing assembly is arranged at the bottom of the upper righting fin assembly; a rotational flow centralizing device is mounted at the bottom of the upper bearing assembly; and a lower bearing assembly is mounted at the bottom of the rotational flow centralizing device. The rotational flow centralizing device can be pushed to rotate by means of flowing of external fluid, so that cleaning liquid is produced to achieve the cleaning effect; and friction can be effectively reduced through the arrangement of the ball device and the anti-drag rolling wheel. And therefore, the service life of the device is prolonged while self-cleaning is ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of oil drilling and geological exploration, and specifically refers to a centralizer device with a composite function of self-rotating cleaning and drag reduction. Background Art

[0002] In recent years, with the continuous progress of oil and gas field exploration and development technologies in China, the requirements for the control accuracy of the wellbore trajectory during the drilling process of the drill string assembly have been increasing day by day. As the core component to ensure the stability of downhole drill tools and effectively prevent well deviation, the centralizer is widely used, and its performance directly affects the success and efficiency of drilling operations.

[0003] However, at present, in actual operations, the centralizer faces many challenges. On the one hand, the space between the two centralizing wings of the existing centralizer serves as the upward return channel for cuttings. It is extremely easy to encounter downhole complex conditions such as mud packing and sticking due to problems such as large volumes of crushed cuttings, which not only increases the drilling risk but also severely restricts the drilling speed. On the other hand, there is a large friction between the existing centralizer and the wellbore or drill pipe during operation. This not only exacerbates the wear of the centralizer itself, shortens its service life, but also leads to an increase in energy consumption, raises the drilling cost, and seriously affects the continuity and efficiency of drilling operations.

[0004] In summary, developing a new type of centralizer with a self-cleaning function, which can significantly reduce the friction coefficient and operate stably in complex and harsh operating environments, can significantly improve drilling efficiency.

[0005] Based on this, the present invention is proposed. Summary of the Invention

[0006] According to an embodiment of the present invention, a centralizer device with a composite function of self-rotating cleaning and drag reduction is provided. It is used to solve the problems in the existing background.

[0007] In the first aspect of the present invention, a centralizer device with a composite function of self-rotating cleaning and drag reduction is provided.

[0008] The centralizer device with a composite function of self-rotating cleaning and drag reduction includes: a joint pipe, a fluid pipe, an upper centralizing wing component, an upper bearing component, a swirl centralizing device, a lower bearing component, a lower centralizing wing component, and a bit joint;

[0009] The bottom of the joint pipe is fixedly connected to the fluid pipe; the upper centralizing vane assembly is fixedly installed on the outside of the fluid pipe and installed below the joint pipe; an upper bearing assembly is provided at the bottom of the upper centralizing vane assembly; a swirl centralizing device is installed at the bottom of the upper bearing assembly; a lower bearing assembly is installed at the bottom of the swirl centralizing device; a lower centralizing vane assembly is installed at the bottom of the lower bearing assembly, and the lower centralizing vane assembly is fixedly installed on the outside of the fluid pipe; a drill bit joint is installed at the bottom of the lower centralizing vane assembly.

[0010] Preferably, the fluid conduit comprises: a pipeline body and drainage ports; there are four drainage ports, which are equidistantly arranged on the pipeline body along the circumferential direction.

[0011] Preferably, the swirl straightening device comprises: a main body, a twisted T-shaped guide groove, a side ball device and a drainage nozzle;

[0012] The upper and lower ends of the main body are fixedly connected to the upper bearing assembly and the lower bearing assembly respectively; there are four twisted T-shaped guide grooves, which are respectively installed on the outer surface of the main body, and the four twisted T-shaped guide grooves are respectively arranged around the main body at equal intervals along the circumferential direction; a vertical opening is provided in the twisted T-shaped guide groove, and its position is opposite to the height position of the drainage port opening; three side ball devices are evenly distributed on each twisted T-shaped guide groove; there are a total of eight drainage nozzles, which are respectively installed on the upper and lower surfaces of the four twisted T-shaped guide grooves, and the drainage nozzles are inclined; the drainage nozzles are set in a tapered shape;

[0013] A groove is provided on the outside of the twisted T-shaped guide groove for assembling the side ball device.

[0014] Preferably, the side ball device comprises: a side ball groove and a side ball;

[0015] The side ball groove is a groove body with an annular sealing structure; the side balls are placed in the arc-shaped raceway of the side ball groove, and the length of the side balls extending out of the side ball groove is less than their own radius.

[0016] Preferably, the upper centralizing wing assembly comprises: a body, a centralizing wing, a roller groove, a drag reduction roller and a ball device;

[0017] The inner surface of the body is fixedly connected to the fluid pipeline; there are four righting vanes, which are equidistantly distributed on the outer surface of the body along the circumferential direction; there are four roller grooves, which are respectively opened in the four righting vanes; the drag-reducing rollers include four groups, which are respectively installed in the roller grooves; three grooves are respectively provided on the upper and lower end walls of the roller grooves on the four righting vanes, and ball devices are embedded in the grooves.

[0018] Preferably, the drag reduction roller comprises: a roller bracket, a bearing and a roller;

[0019] There are two roller brackets, which are symmetrically installed on the upper and lower walls of the roller groove; cylindrical grooves are reserved on the opposite sides of the two roller brackets, and there are two bearings, which are rotatably installed in the cylindrical grooves reserved in the two roller brackets; the two bearings are respectively inserted into the shaft necks at both ends of the roller.

[0020] Preferably, the ball device comprises: a ball groove and a drag-reducing ball; the drag-reducing ball is placed in the ball groove.

[0021] Preferably, the upper bearing assembly includes: a shaft ring, a retaining frame, a rolling element, a shaft seat, and a seat ring;

[0022] The shaft seat is installed at the bottom position of the upper righting vane assembly, and the center line of the shaft seat coincides with the axis of the upper righting vane assembly and the fluid pipeline; the shaft ring is installed at the top inner side of the shaft seat, and the inner surface of the shaft ring is tightly connected with the fluid pipeline; the seat ring is installed at the bottom inner side of the shaft seat, and the outer circular surface of the seat ring is tightly fitted with the bottom end of the inner surface of the shaft seat; the retaining frame is a circular ring structure, and is installed in the annular space between the shaft ring and the seat ring; a plurality of ball grooves are provided on the retaining frame, and a plurality of rolling bodies are equidistantly embedded in the plurality of ball grooves on the retaining frame along the circumferential direction, and the rolling body is a cylinder and its upper end is in rolling contact with the lower surface of the shaft ring.

[0023] Preferably, the lower centralizing wing assembly and the upper centralizing wing assembly are symmetrically arranged relative to the swirl centralizing device; the lower centralizing wing assembly comprises: a lower body, a lower centralizing wing, a lower roller groove, a lower drag reduction roller and a lower ball device;

[0024] The inner surface of the lower body is fixedly connected to the fluid pipeline; there are four lower righting vanes, which are equidistantly distributed on the outer surface of the lower body along the circumferential direction; there are four lower roller grooves, which are respectively opened in the four lower righting vanes; the lower drag reduction rollers include four groups, which are respectively installed in the lower roller grooves; the four lower righting vanes are each provided with three linearly arranged cylindrical grooves on the upper and lower end walls of the lower roller grooves, and the lower ball device is embedded in the grooves.

[0025] Preferably, the lower bearing assembly comprises: a lower shaft ring, a lower retaining frame, a lower rolling element, a lower shaft seat and a lower seat ring;

[0026] The lower shaft seat is installed at the top position of the lower centralizer vane assembly, and the center line of the lower shaft seat coincides with the axes of the lower centralizer vane assembly and the fluid pipeline; the lower shaft ring is installed at the inner bottom end of the shaft seat, and the inner surface of the lower shaft ring is closely connected to the fluid pipeline; the lower seat ring is installed at the inner top end of the lower shaft seat, and the outer circular surface of the lower seat ring is closely attached to the inner surface top end of the lower shaft seat; the lower cage is in an annular structure and is installed in the annular space between the lower shaft ring and the seat ring; a number of ball grooves are provided on the lower cage, and a number of lower rolling elements are evenly embedded in the number of ball grooves on the lower cage along the circumference, wherein the lower rolling elements are spherical and their bottom ends are in rolling contact with the upper surface of the lower shaft ring.

[0027] One or more technical solutions provided in this application have at least the following technical effects or advantages:

[0028] 1. A centralizer device with a self-rotating cleaning and drag reduction composite function provided by the present invention, wherein a transverse drainage port is provided on the fluid pipeline, and a diversion groove is provided on the swirl centralizer device at the same position. When the drainage port on the swirl centralizer device corresponds to the notch of the diversion groove, the fluid will flow out along the diversion groove, thereby providing liquid for cleaning the mud cake.

[0029] 2. The swirl centralizer device in the present invention is provided with inclined diversion grooves. By utilizing the fluid movement, a thrust can be generated based on a unique structural design to push the swirl centralizer device to rotate automatically. During the rotation process, cleaning liquid is continuously generated to effectively scour the mud cake on the surface of the centralizer vane circumferentially, realizing automatic cleaning.

[0030] 3. The drainage nozzle in the present invention adopts an inclined angle design and a gradually shrinking nozzle opening design. This design can effectively improve the flushing strength, expand the cleaning range, and at the same time reduce the fluid resistance, reduce the system energy consumption while ensuring the cleaning effect, and improve the resource utilization efficiency.

[0031] 4. In the present invention, ball devices and drag reduction rollers with different azimuth angles are provided to ensure that the centralizer effectively reduces the friction with the wall surface during rotation and vertical movement. In addition, the heights of the ball devices are also different, enabling the device to flexibly adapt to complex uneven walls, significantly extending the service life of the device, reducing the equipment replacement frequency, and saving costs.

[0032] In summary, the present invention can drive the rotation of the swirl centralizer device by means of the external fluid flow to produce cleaning liquid to achieve the cleaning effect. At the same time, the setting of the ball device and the drag reduction roller can effectively reduce friction and resistance. This design ensures self-cleaning while extending the service life of the device.

[0033] It should be understood that the content described in the Summary of the Invention section is not intended to limit the key or important features of the embodiments of the present invention, nor to limit the scope of the present invention. Other features of the present invention will become readily understood through the following description. Brief Description of the Drawings

[0034] In conjunction with the accompanying drawings and with reference to the following detailed description, the above and other features, advantages, and aspects of the embodiments of the present invention will become more apparent. In the drawings, like or similar reference numerals denote like or similar elements, where:

[0035] Figure 1 The front view of a centralizer device with a self-rotating cleaning and drag reduction composite function according to an embodiment of the present invention is shown;

[0036] Figure 2 The front view structural schematic diagram of a centralizer device with a self-rotating cleaning and drag reduction composite function according to an embodiment of the present invention is shown;

[0037] Figure 3 The top view structural schematic diagram of a centralizer device with a self-rotating cleaning and drag reduction composite function according to an embodiment of the present invention is shown;

[0038] Figure 4 The front view sectional view of a centralizer device with a self-rotating cleaning and drag reduction composite function according to an embodiment of the present invention is shown;

[0039] Figure 5 The front view of the upper centralizing fin assembly of a centralizer device with a self-rotating cleaning and drag reduction composite function according to an embodiment of the present invention is shown;

[0040] Figure 6 The perspective view of the upper centralizing fin assembly of a centralizer device with a self-rotating cleaning and drag reduction composite function according to an embodiment of the present invention is shown;

[0041] Figure 7 The structural schematic diagram of a drag reduction roller of a centralizer device with a self-rotating cleaning and drag reduction composite function according to an embodiment of the present invention is shown;

[0042] Figure 8 The structural schematic diagram of the upper bearing assembly of a centralizer device with a self-rotating cleaning and drag reduction composite function according to an embodiment of the present invention is shown;

[0043] Figure 9 The front view of a cyclone centralizer device with a self-rotating cleaning and drag reduction composite function according to an embodiment of the present invention is shown;

[0044] Figure 10 The perspective view of a flow centralizer device with a self-rotating cleaning and drag reduction composite function according to an embodiment of the present invention is shown.

[0045] The reference numerals are as follows:

[0046] 1. Connector pipe

[0047] 2. Fluid pipe; 2-1. Pipe body; 2-2. Drainage port

[0048] 3. Upper centering fin assembly; 3-a. Body; 3-1. Centering fin; 3-2. Roller groove; 3-3. Drag reduction roller; 3-3-1. Roller bracket; 3-3-2. Bearing; 3-3-3. Drum; 3-4. Drag reduction ball; 3-4-1. Ball groove; 3-4-2. Drag reduction ball

[0049] 4. Upper bearing assembly; 4-1. Axial ring; 4-2. Cage; 4-3. Rolling element; 4-4. Axial seat; 4-5. Raceway

[0050] 5. Swirl centering device; 5-a. Main body; 5-1. Twisted T-shaped flow guiding groove; 5-2. Side ball device; 5-2-1. Ball groove; 5-2-2. Ball; 5-3. Drainage nozzle

[0051] 6. Lower bearing assembly; 6-1. Lower axial ring; 6-2. Lower cage; 6-3. Lower rolling element; 6-4. Lower axial seat; 6-5. Lower raceway

[0052] 7. Lower centering fin assembly; 7-a. Lower body; 7-1. Lower centering fin; 7-2. Lower roller groove; 7-3. Lower drag reduction roller; 7-3-1. Lower roller bracket; 7-3-2. Lower bearing; 7-3-3. Lower drum; 7-4. Lower ball device

[0053] 8. Bit sub Detailed implementation manners

[0054] In order to make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Apparently, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0055] In addition, the term "and / or" in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this article generally represents an "or" relationship between the front and rear associated objects.

[0056] Such as Figure 1 , Figure 2 and Figure 3As shown in the figure, the centralizer device with the composite function of self-rotating cleaning and drag reduction includes: a joint pipe 1, a fluid pipe 2, an upper centralizing fin assembly 3, an upper bearing assembly 4, a swirl centralizing device 5, a lower bearing assembly 6, a lower centralizing fin assembly 7, and a bit sub 8. An opening is provided on the joint pipe 1, and threads are provided on the inner surface of the joint pipe 1. The drill pipe of the external device can be fixedly connected to the joint pipe 1 through the threads, realizing the fixed connection between the two. The bottom of the joint pipe 1 is fixedly connected to the fluid pipe 2. The fluid pipe 2 is composed of a pipe body 2-1 and drainage ports 2-2. There are four drainage ports 2-2, which are evenly arranged circumferentially on the pipe body 2-1. Among them, the drainage ports 2-2 are opened horizontally, which can increase the contact area and ensure that more fluid can be output through the drainage ports 2-2 when the fluid passes through the pipe body 2-1 in the fluid pipe 2. The upper centralizing fin assembly 3 is fixedly installed on the outside of the fluid pipe 2 and is installed below the joint pipe 1. The bottom of the upper centralizing fin assembly 3 is provided with an upper bearing assembly 4, and the upper bearing assembly 4 is installed on the outside of the fluid pipe 2. The swirl centralizing device 5 is installed at the bottom of the upper bearing assembly 4. The swirl centralizing device 5 is installed at the bottom of the lower bearing assembly 6, and the lower bearing assembly 6 is installed on the outside of the fluid pipe 2. The swirl centralizing device 5 is rotatably installed on the outside of the fluid pipe 2 through the upper bearing assembly 4 and the lower bearing assembly 6. The upper bearing assembly 4 and the lower bearing assembly 6 ensure that the swirl centralizing device 5 can rotate relative to the fluid pipe 2, thereby realizing the rotary ejection of the fluid. The lower bearing assembly 6 is installed at the bottom of the lower centralizing fin assembly 7, and the lower centralizing fin assembly 7 is fixedly installed on the outside of the fluid pipe 2. The settings of the upper centralizing fin assembly 3 and the lower centralizing fin assembly 7 can effectively prevent the pipe string from deflecting. The bit sub 8 is installed at the bottom of the lower centralizing fin assembly 7. The inner surface of the bit sub 8 is connected to the outer surface of the fluid pipe 2, and threads are provided on the outer surface of the bit sub 8. The external drilling tool can be connected to the bit sub 8 through the threads. The upper centralizing fin assembly 3, the upper bearing assembly 4, the swirl centralizing device 5, the lower bearing assembly 6, the lower centralizing fin assembly 7, and the bit sub 8 are coaxially arranged with the fluid pipe 2.

[0057] As Figure 4 , Figure 5 , Figure 6 , Figure 7As shown, the upper righting vane assembly 3 includes a body 3-a, righting vanes 3-1, roller grooves 3-2, drag-reducing rollers 3-3, and a ball device 3-4. The inner surface of the body 3-a is fixedly connected to the fluid pipeline 2. There are four righting vanes 3-1, which are evenly spaced along the circumference on the outer surface of the body 3-a. The angle between adjacent vanes is 90°, ensuring all-round force balance and righting the pipe column. There are four roller grooves 3-2, each of which is located within the four righting vanes 3-1. The roller grooves 3-2 have a rectangular through-hole structure. The drag-reducing rollers 3-3 are included in four groups, each corresponding to the number of roller grooves 3-2. Each group of drag-reducing rollers 3-3 consists of a roller bracket 3-3-1, a bearing 3-3-2, and a roller 3-3-3. There are two L-shaped roller brackets 3-3-1, symmetrically mounted on the upper and lower walls of the roller groove 3-2. The spacing between the two roller brackets 3-3-1 matches the length of the roller 3-3-3, and cylindrical grooves are reserved on opposite sides of the roller brackets 3-3-1. Two bearings 3-3-2 are provided, each rotatably mounted within the cylindrical grooves of the two roller brackets 3-3-1. The two bearings 3-3-2 are inserted into the journals at each end of the roller 3-3-3, ensuring that the roller 3-3-3 can rotate freely around the axis of the bearings 3-3-2. The outer side of the roller 3-3-3 extends beyond the inner cavity of the roller groove 3-2, ensuring contact between the roller 3-3-3 and the rock wall, reducing friction on the main body 3-a. The four righting vanes 3-1 each have three linearly arranged cylindrical grooves on the upper and lower end walls of the roller groove 3-2. These grooves house a ball assembly 3-4, which includes a ball groove 3-4-1 and drag-reducing balls 3-4-2. The ball groove 3-4-1 is mounted within the cylindrical groove, and the drag-reducing balls 3-4-2 are positioned coaxially with the groove. The drag-reducing balls 3-4-2 can roll freely within the groove 3-4-1, while the groove 3-4-1 effectively limits the position of the drag-reducing balls 3-4-2, preventing them from derailing. A ring is fixed on the ball groove 3-4-1, and its diameter is the same as that of the cylindrical groove to ensure a sealed installation. The diameter of the drag-reducing ball 3-4-2 extending out of the ring is smaller than its own radius to prevent the drag-reducing ball 3-4-2 from falling out.

[0058] It will be appreciated that in this embodiment, the upper centering vane assembly 3 effectively reduces friction between itself and the rock wall through the coordinated design of the drag-reducing roller 3-3 and the ball device 3-4. Specifically, the roller 3-3-3 of the drag-reducing roller 3-3 protrudes from the roller groove 3-2, allowing direct contact with the rock wall, converting sliding friction into rolling friction. The drag-reducing balls 3-4-2 in the ball device 3-4 can roll freely within the ball groove 3-4-1, further reducing contact resistance. Furthermore, the inner surface of the body 3-a of the upper centering vane assembly 3 is connected to the fluid pipeline 2. By utilizing the contact and positioning of the drag-reducing roller 3-3 and the ball device 3-4 with the inner wall of the wellbore, the upper centering vane assembly 3 can be vertically inserted into the wellbore, thereby preventing the pipe string from deflecting or sticking to the wall.

[0059] like Figure 8 、 Figure 9 As shown, the upper bearing assembly 4 includes a shaft ring 4-1, a retaining frame 4-2, a rolling element 4-3, a shaft seat 4-4, and a seat ring 4-5. The shaft seat 4-4 is installed at the bottom position of the upper righting vane assembly 3 and is fixedly connected to the bottom of the upper righting vane assembly 3. The shaft seat 4-4 as a whole presents a hollow cylindrical structure. The upper end of the shaft seat 4-4 is in the shape of a circular ring. The inner ring of the circular ring fits tightly with the fluid pipeline 2 to form a sealed whole. The lower end is a circular ring opening. The center line of the shaft seat 4-4 coincides with the axis of the upper righting vane assembly 3 and the fluid pipeline 2. The shaft ring 4-1 is installed at the top inner side of the shaft seat 4-4. The inner surface of the shaft ring 4-1 is tightly connected to the fluid pipeline 2 and is in a fixed state. The seat ring 4-5 is mounted on the inner bottom end of the shaft seat 4-4. The outer surface of the seat ring 4-5 fits tightly against the inner bottom end of the shaft seat 4-4. The seat ring 4-5 can rotate relative to the shaft seat 4-4 while maintaining a sealing effect. The inner diameter of the seat ring 4-5 is larger than the inner diameter of the shaft ring 4-1, ensuring a gap between the seat ring 4-5 and the swirl straightening device 5 at its bottom end and the fluid pipeline 2 to avoid interference. At the same time, it ensures that the seat ring 4-5 and the swirl straightening device 5 can rotate relative to the fluid pipeline 2. The positioning stop formed between the lower surface of the seat ring 4-5 and the lower end of the shaft seat 4-4 is used to cooperate with the upper end of the swirl straightening device 5 for positioning. The retaining frame 4-2 is a circular ring structure and is installed in the annular space between the shaft ring 4-1 and the seat ring 4-5. There are several ball grooves on the retaining frame 4-2, and there are several rolling bodies 4-3, which are embedded in the ball grooves on the retaining frame 4-2 at equal intervals along the circumferential direction. The rolling bodies 4-3 are cylindrical and their upper ends are in rolling contact with the lower surface of the shaft ring 4-1. The rolling bodies 4-3 can roll freely in the ball grooves, thereby ensuring that the seat ring 4-5 as a whole can rotate smoothly.

[0060] It can be understood that in this embodiment, the upper bearing assembly 4 is integrally installed below the upper centralizing vane assembly 3. The inner surface of the shaft ring 4-1 is tightly connected to the fluid pipeline 2 and is in a fixed state. The inner diameter of the seat ring 4-5 is larger than the inner diameter of the shaft ring 4-1, and there is a gap between it and the fluid pipeline 2, ensuring that the seat ring 4-5 can rotate to avoid interference with the fluid pipeline 2. The bottom end of the seat ring 4-5 is connected to the swirl centralizing device 5. Thus, it is ensured that the swirl centralizing device 5 can rotate independently relative to the fluid pipeline 2, the upper centralizing vane assembly 3, and the lower centralizing vane assembly 7.

[0061] As Figure 4 shown, the lower centralizing vane assembly 7 and the upper centralizing vane assembly 3 are symmetrically arranged relative to the swirl centralizing device 5. The lower centralizing vane assembly 7 includes a lower body 7-a, lower centralizing vanes 7-1, lower roller grooves 7-2, lower drag-reducing rollers 7-3, and lower ball devices 7-4. The inner surface of the lower body 7-a is fixedly connected to the fluid pipeline 2. There are 4 lower centralizing vanes 7-1, and the 4 lower centralizing vanes 7-1 are evenly distributed circumferentially on the outer surface of the lower body 7-a, with an included angle of 90° between adjacent vanes, ensuring balanced force in all directions and centralizing the pipe string. There are 4 lower roller grooves 7-2, and the 4 lower roller grooves 7-2 are respectively opened within the 4 lower centralizing vanes 7-1. The groove body of the lower roller groove 7-2 is a rectangular through structure. The lower drag-reducing rollers 7-3 include 4 groups, which are respectively installed in the lower roller grooves 7-2 in one-to-one correspondence with the number of the lower roller grooves 7-2. Each group of lower drag-reducing rollers 7-3 consists of a lower roller bracket 7-3-1, a lower bearing 7-3-2, and a lower drum 7-3-3. There are two lower roller brackets 7-3-1, which are "L"-shaped members, symmetrically installed on the upper and lower wall surfaces of the lower roller groove 7-2. The distance between the two lower roller brackets 7-3-1 matches the length of the lower drum 7-3-3. A cylindrical groove is reserved on the opposite side of the two lower roller brackets 7-3-1. A total of 2 lower bearings 7-3-2 are provided, which are respectively rotatably installed in the cylindrical grooves reserved by the two lower roller brackets 7-3-1. The two lower bearings 7-3-2 are respectively inserted into the end journals of the two ends of the lower drum 7-3-3, ensuring that the lower drum 7-3-3 can freely rotate around the axis of the lower bearing 7-3-2. The outer side of the lower drum 7-3-3 extends out of the inner cavity of the lower roller groove 7-2, which can ensure that the lower drum 7-3-3 contacts the rock wall surface and reduces the friction on the lower body 7-a. On the upper and lower end walls of the 4 lower centralizing vanes 7-1 where the lower roller grooves 7-2 are located, 3 linearly arranged cylindrical grooves are provided respectively, and the lower ball devices 7-4 are embedded in the grooves. The structural composition of the lower ball devices 7-4 is the same as that of the ball devices 3-4.

[0062] It can be understood that in this embodiment, by setting the drag reduction roller 7-3 and the ball device 7-4, the friction with the rock wall surface can be avoided. In addition, the inner surface of the main body 7-a in the lower centralizer vane assembly 7 is connected to the fluid pipeline 2, and by fitting and limiting the drag reduction roller 3-3 and the drag reduction ball 3-4 with the inner wall of the wellbore, the lower centralizer vane assembly 7 can enter the wellbore vertically as a whole, thereby avoiding the deviation or wall sticking of the pipe string. In addition, the lower centralizer vane assembly 7 has the same structure as the upper centralizer vane assembly 3 and is symmetrically arranged with respect to the swirl centralizer device 5, which can ensure the uniform and stable force of the whole equipment.

[0063] As Figure 9 shown, the lower bearing assembly 6 includes a lower race 6-1, a lower cage 6-2, lower rolling elements 6-3, a lower shaft seat 6-4, and a lower washer 6-5. The lower shaft seat 6-4 is installed at the top position of the lower centralizer vane assembly 7. The lower shaft seat 6-4 is integrally in the shape of a hollow cylinder, the bottom end of the lower shaft seat 6-4 is in the shape of a ring, and the inner ring of the ring is closely attached to the fluid pipeline 2 to form a sealed whole, and the top end is a ring-shaped opening. The center line of the lower shaft seat 6-4 coincides with the axes of the lower centralizer vane assembly 7 and the fluid pipeline 2. The lower race 6-1 is installed at the inner bottom end of the shaft seat 6-4, and the inner surface of the lower race 6-1 is closely connected to the fluid pipeline 2 and is in a fixed state. The lower washer 6-5 is installed at the inner top end of the lower shaft seat 6-4, and the outer circular surface of the lower washer 6-5 is closely attached to the inner surface of the top end of the lower shaft seat 6-4. The lower washer 6-5 can rotate relative to the lower shaft seat 6-4 and still ensure the sealing effect during rotation. The inner diameter of the lower washer 6-5 is larger than the inner diameter of the lower race 6-1, ensuring that there is a gap between the lower washer 6-5 and the swirl centralizer device 5 and the fluid pipeline 2 at its top end to avoid interference, and at the same time ensuring that the lower washer 6-5 can rotate relative to the fluid pipeline 2. The positioning stop formed by the upper surface of the lower washer 6-5 and the upper end of the lower shaft seat 6-4 is used for positioning with the lower end of the swirl centralizer device 5. The lower cage 6-2 is in a circular ring structure and is installed in the annular space between the lower race 6-1 and the washer 6-5. A number of ball grooves are provided on the lower cage 6-2, and a number of lower rolling elements 6-3 are evenly embedded in the number of ball grooves on the lower cage 6-2 along the circumferential direction. Among them, the lower rolling element 6-3 is a cylinder and its bottom end is in rolling contact with the upper surface of the lower race 6-1. The lower rolling element 6-­3 can roll freely in the ball groove, thereby ensuring the smooth rotation of the whole lower washer 6-5.

[0064] It is understood that in this embodiment, the lower bearing assembly 6 is integrally mounted above the lower righting vane assembly 7. It is symmetrically arranged with the upper bearing assembly 4 relative to the swirl righting device 5 and has the same structure. The two work together to ensure smooth rotation of the swirl righting device 5 relative to the fluid pipeline 2. The inner surface of the lower shaft ring 6-1 is tightly connected to the fluid pipeline 2 and is in a fixed state. The inner diameter of the lower seat ring 6-5 is larger than the inner diameter of the lower shaft ring 6-1, and a gap exists between the lower seat ring 6-5 and the fluid pipeline 2, ensuring that the lower seat ring 6-5 can rotate without interfering with the fluid pipeline 2. The top end of the lower seat ring 6-5 is connected to the swirl righting device 5. This ensures that the swirl righting device 5 can rotate independently relative to the fluid pipeline 2, the upper righting vane assembly 3, and the lower righting vane assembly 7.

[0065] like Figure 9 、 Figure 10 As shown, the swirl straightening device 5 includes a main body 5-a, a twisted T-shaped guide groove 5-1, a side ball device 5-2, and a drainage nozzle 5-3. The upper and lower ends of the main body 5-a of the swirl straightening device 5 are fixedly connected to the upper bearing assembly 4 and the lower bearing assembly 6 respectively, and the main body 5-a is located on the outside of the fluid pipeline 2. There are four twisted T-shaped guide grooves 5-1, which are respectively installed on the outer surface of the main body 5-a, and the four twisted T-shaped guide grooves 5-1 are respectively arranged around the main body 5-a at equal distances along the circumference, with a twisting angle of 45 degrees. A vertical opening is provided in the twisted T-shaped guide groove 5-1, and its position is opposite to the opening height position of the drainage port 2-2, ensuring that after the fluid enters the pipeline main body 2-1, it can enter each guide groove 5-1 through the drainage port 2-2. There is a gap between the main body 5-a and the fluid pipeline 2, which effectively avoids the friction loss caused by contact during the rotation of the device. A groove is provided on the outside of the twisted T-shaped guide groove 5-1 for mounting the side ball device 5-2. Three side ball devices 5-2 are evenly distributed on each twisted T-shaped guide groove 5-1, for a total of 12. The side ball device 5-2 consists of a side ball groove 5-2-1 and a side ball 5-2-2. The side ball groove 5-2-1 is a groove body with an annular sealing structure, and its outer diameter is tightly matched with the cylindrical groove. The side ball 5-2-2 is placed in the arc-shaped raceway of the side ball groove 5-2-1. The length of the side ball 5-2-2 extending out of the side ball groove 5-2-1 is less than its own radius. The raceway structure design can effectively limit the side ball 5-2-2 in all directions to prevent the side ball 5-2-2 from falling off the track. There are a total of 8 diversion nozzles 5-3, which are respectively installed on the upper and lower surfaces of the four twisted T-shaped guide grooves 5-1. The flow-guiding nozzle 5-3 is directly opposite to the outlet of the twisted T-shaped guide groove 5-1 and is inclined. At the same time, the flow-guiding nozzle 5-3 adopts a tapered structural design.

[0066] It can be understood that in this embodiment, the swirl centralizer 5 is installed between the upper bearing assembly 4 and the lower bearing assembly 6. The swirl centralizer 5 is provided with a twisted T-shaped flow guiding groove 5-1. By using the impact of external flowing fluids such as drilling fluid, the swirl centralizer 5 rotates around its own axis, and by using the action of internal cleaning fluid and other fluids, the overall rotation of the swirl centralizer 5 is assisted. The specific method is as follows: When the external fluid flows through the surface of the swirl centralizer 5, since the twisted T-shaped flow guiding groove 5-1 is twisted at 45 degrees and there is an inclined angle with the fluid contact surface, a lateral thrust will be generated, causing the swirl centralizer 5 to start rotating. During this process, the internal fluid enters the pipeline body 2-1. Most of the fluid is output through the drill bit sub 8, and a small part of the fluid is input into the gap between the main body 5-a and the fluid pipeline 2 through the drainage port 2-2. As the swirl centralizer 5 rotates, when the notch of the twisted T-shaped flow guiding groove 5-1 corresponds to the position of the drainage port 2-2, the fluid in the fluid pipeline 2 and the fluid remaining in the gap will enter through the notch of the twisted T-shaped flow guiding groove 5-1 and finally be ejected through the drainage nozzle 5-3. Since both the twisted T-shaped flow guiding groove 5-1 and the drainage nozzle 5-3 are inclined, the inclined water flow ejected when acting on the drilling wall will also generate a lateral thrust, and then assist the rotation of the main body 5-a through the reaction force, increasing the rotation speed and realizing the circumferential cleaning of the mud cake on the upper centralizer vane assembly 3 and the lower centralizer vane assembly 7. Among them, when the fluid passes through the drainage nozzle 5-3 that rotates together with the swirl centralizer 5 and is ejected, due to its tapered structure, a high-speed and large-angle jet water flow can be further generated. In addition, the ball device 5-2 is arranged on the twisted T-shaped flow guiding groove 5-1, which can reduce the friction between the upper centralizer vane assembly 3, the upper bearing assembly 4, the lower bearing assembly 6, the lower centralizer vane assembly 7 and the drill bit sub 8 and the rock wall surface.

[0067] The above specific embodiments do not constitute a limitation to the protection scope of the present invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A centralizer device with the composite functions of self-rotating cleaning and drag reduction, characterized in that, Comprising: Adapter pipe, fluid pipe, upper centralizer vane assembly, upper bearing assembly, swirl centralizer device, lower bearing assembly, lower centralizer vane assembly and bit sub; The bottom of the adapter pipe is fixedly connected to the fluid pipe; the upper centralizer vane assembly is fixedly installed on the outside of the fluid pipe and below the adapter pipe; the bottom of the upper centralizer vane assembly is provided with an upper bearing assembly; the swirl centralizer device is installed at the bottom of the upper bearing assembly; the lower bearing assembly is installed at the bottom of the swirl centralizer device; the lower bearing assembly is installed with a lower centralizer vane assembly at the bottom, and the lower centralizer vane assembly is fixedly installed on the outside of the fluid pipe; the bottom of the lower centralizer vane assembly is installed with a bit sub.

2. The centralizer device with the composite function of self-rotating cleaning and drag reduction according to claim 1, characterized in that, The fluid pipe includes: a pipe body and drainage openings; there are four drainage openings, which are circumferentially and equidistantly opened on the pipe body.

3. The centralizer device with the composite function of self-rotating cleaning and drag reduction according to claim 2, characterized in that, The swirl centralizer device includes: a main body, twisted T-shaped diversion grooves, side ball devices and drainage nozzles; The upper and lower ends of the main body are respectively fixedly connected to the upper bearing assembly and the lower bearing assembly; there are four twisted T-shaped diversion grooves, which are respectively installed on the outer surface of the main body, and the four twisted T-shaped diversion grooves are respectively arranged around the main body circumferentially and equidistantly; a vertical opening is provided in the twisted T-shaped diversion groove, and its position is opposite to the opening height position of the drainage opening; three side ball devices are evenly distributed on each of the twisted T-shaped diversion grooves; there are a total of eight drainage nozzles, which are respectively installed on the upper and lower surfaces of the four twisted T-shaped diversion grooves, and the drainage nozzles are inclined; the drainage nozzles are tapered; A groove is provided outside the twisted T-shaped diversion groove for fitting the side ball device.

4. The centralizer device with the composite function of self-rotating cleaning and drag reduction according to claim 3, characterized in that The side ball device includes: a side ball groove and side balls; The side ball groove is a groove body with an annular sealing structure; the side balls are placed in the arc-shaped raceway of the side ball groove, and the length of the side balls extending out of the side ball groove is less than their own radius.

5. The centralizer device with the composite function of self-rotating cleaning and drag reduction according to any one of claims 1-4, characterized in that, The upper centralizer vane assembly includes: a body, centralizer vanes, roller grooves, drag-reducing rollers and ball devices; The inner surface of the body is fixedly connected to the fluid pipe; there are four centralizer vanes, and the four centralizer vanes are circumferentially and equidistantly distributed on the outer surface of the body; there are four roller grooves, and the four roller grooves are respectively opened in the four centralizer vanes; the drag-reducing rollers include four groups, which are respectively installed in the roller grooves; three grooves are provided on the upper and lower end walls of the four centralizer vanes at the positions of the roller grooves, and ball devices are embedded in the grooves.

6. The centralizer device with the composite function of self-rotating cleaning and drag reduction according to claim 5, characterized in that, The drag-reducing roller includes: a roller bracket, a bearing and a roller; There are two roller brackets, which are symmetrically installed on the upper and lower wall surfaces of the roller groove; a cylindrical groove is reserved on the opposite side of the two roller brackets, and there are two bearings, which are respectively rotatably installed in the cylindrical grooves reserved by the two roller brackets; the two bearings are respectively inserted into the shaft necks at both ends of the roller.

7. The centralizer device with the composite function of self-rotating cleaning and drag reduction according to claim 6, characterized in that, The ball device includes: a ball groove and drag-reducing balls; the drag-reducing balls are placed in the ball groove.

8. The centralizer device with the composite function of self-rotating cleaning and drag reduction according to claim 7, characterized in that The upper bearing assembly includes: an outer ring, a cage, rolling elements, a shaft seat, a seat ring; The shaft seat is installed at the bottom position of the upper righting vane assembly, and the center line of the shaft seat coincides with the axis of the upper righting vane assembly and the fluid pipeline; the shaft ring is installed at the top inner side of the shaft seat, and the inner surface of the shaft ring is tightly connected with the fluid pipeline; the seat ring is installed at the bottom inner side of the shaft seat, and the outer circular surface of the seat ring is tightly fitted with the bottom end of the inner surface of the shaft seat; the retaining frame is a circular ring structure, and is installed in the annular space between the shaft ring and the seat ring; a plurality of ball grooves are opened on the retaining frame, and a plurality of rolling bodies are embedded in the plurality of ball grooves on the retaining frame at equal intervals along the circumferential direction, and the rolling body is a cylinder whose upper end is in rolling contact with the lower surface of the shaft ring.

9. The centralizer device with the composite function of self-rotating cleaning and drag reduction according to claim 8, characterized in that, The lower centralizing wing assembly and the upper centralizing wing assembly are symmetrically arranged relative to the swirl centralizing device; the lower centralizing wing assembly comprises: a lower body, a lower centralizing wing, a lower roller groove, a lower drag reduction roller and a lower ball device; The inner surface of the lower body is fixedly connected to the fluid pipeline; there are four lower righting vanes, which are equidistantly distributed on the outer surface of the lower body along the circumferential direction; there are four lower roller grooves, which are respectively opened in the four lower righting vanes; the lower drag reduction rollers include four groups, which are respectively installed in the lower roller grooves; the four lower righting vanes are each provided with three linearly arranged cylindrical grooves on the upper and lower end walls of the lower roller grooves, and the lower ball device is embedded in the grooves.

10. The centralizer device with the composite function of self-rotating cleaning and drag reduction according to claim 9, characterized in that, The lower bearing assembly includes: a lower shaft ring, a lower retaining frame, a lower rolling element, a lower shaft seat and a lower seat ring; The lower shaft seat is installed at the top position of the lower straightening vane assembly, and the center line of the lower shaft seat coincides with the axis of the lower straightening vane assembly and the fluid pipeline; the lower shaft ring is installed at the bottom end of the inner side of the shaft seat, and the inner surface of the lower shaft ring is tightly connected with the fluid pipeline; the lower seat ring is installed at the top end of the inner side of the lower shaft seat, and the outer circular surface of the lower seat ring is tightly fitted with the top end of the inner surface of the lower shaft seat; the lower retaining frame is a circular ring structure, which is installed in the annular space between the lower shaft ring and the seat ring; a plurality of ball grooves are opened on the lower retaining frame, and there are a plurality of lower rolling bodies, which are equidistantly embedded in the plurality of ball grooves on the lower retaining frame along the circumferential direction, wherein the lower rolling body is a cylinder and its bottom end is in rolling contact with the upper surface of the lower shaft ring.

Images