Multi-channel drill pipe having adaptively interconnected channels

Abstract

A drill pipe having multiple channels adaptively communicated with each other comprises a plurality of pipe bodies (1) connected end to end, wherein each pipe body comprises an inner pipe (11) and an outer pipe (12) sleeved outside the inner pipe, a first fluid channel (13) is formed in the middle of the inner pipe, and the inner pipe and the outer pipe are separated by means of two partition plates (14) to form a second fluid channel (15) and a third fluid channel (16); the pipe body further comprises a concentric joint (2), the concentric joint comprises joint bodies (21) arranged at two ends of the inner pipe, a first concentric channel (22) is formed between each joint body and the outer pipe, and a second concentric channel (23) is formed between each joint body and the inner pipe, the first concentric channel is configured to be communicated with the second fluid channel but not with the third fluid channel, and the second concentric channel is configured to be communicated with the third fluid channel but not with the second fluid channel. According to the drill pipe having multiple channels, the inner pipes and the outer pipes are separated to form a multi-channel structure, thereby reducing the space occupation of the drill pipe in the radial direction, avoiding impact on the use effect of the drill pipe.

Description

Adaptive connected multi-channel drill pipe

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of Chinese patent application No. 202410077399.7 filed on January 18, 2024, the contents of which are incorporated herein by reference. Technical Field

[0003] The present invention relates to the technical field of drilling, in particular to an adaptive connected multi-channel drill pipe. Background Art

[0004] With the long-term exploitation of shallow oil and gas resources, shallow oil and gas resources are constantly decreasing. To meet the growing energy demand, the depth and difficulty of oil and gas well drilling are constantly increasing. Deep wells, ultra-deep wells and other complex drilling operations account for an increasing proportion of exploration and development in China and abroad. As deep wells, ultra-deep wells and other complex drilling operations increase, the performance and function of drill pipes are also increasingly demanding.

[0005] The drill pipe is a key component of the oil drill string, primarily used for tripping tools, transporting drilling fluid, applying weight-on-bit torque, and facilitating the connection of downhole tools. Downhole power transmission has always been a key function of the drill pipe. The operation of downhole power drilling tools, the transport of cuttings, and the regulation of bottomhole pressure all rely on the drill pipe's drilling fluid flow and pressure regulation.

[0006] However, the existing drill pipe technology has only one drilling fluid flow path. The drilling fluid is injected from the wellhead, flows through the drill bit and returns to the ground through the wellbore annulus. The drilling fluid is used to drive the downhole power drilling tool. On the one hand, it puts higher requirements on the pressure of the ground drilling pump. In addition, with the gradual increase in drilling depth, the existing drilling pumps can no longer meet the demand. On the other hand, the single drilling fluid flow path requires consideration of multiple factors when adjusting the drilling fluid parameters. Changing the drilling fluid displacement and pressure may not be able to meet multiple needs, resulting in no parameter space for adjustment and extremely poor flexibility and independence.

[0007] Multi-channel drill pipes were developed to address this need. However, because the multiple channels are spaced apart along the circumference of the drill pipe, the multiple channels on two adjacent drill pipes do not align during installation, preventing fluid from entering the corresponding channels, which affects the use of the drill pipe. Current multi-channel drill pipes often use a multi-casing structure, where multiple casings are spaced apart along the radial direction to form channels between adjacent casings. However, this multi-channel casing increases the diameter of the drill pipe, resulting in significant pressure loss and making it difficult to guarantee the effectiveness of the drill pipe.

[0008] Summary of the Invention

[0009] In order to solve the above technical problem or at least partially solve the above technical problem, the present invention provides an adaptive connected multi-channel drill pipe.

[0010] The present invention provides an adaptively connected multi-channel drill pipe, comprising a plurality of rod bodies connected end to end, the rod body comprising an inner tube and an outer tube that are sleeved together, a first fluid channel being formed in the middle of the inner tube, the inner tube and the outer tube being separated by two partitions to form a second fluid channel and a third fluid channel between the inner tube and the outer tube, the rod body further comprising a concentric joint, the concentric joint comprising a joint body arranged at both ends of the inner tube, the two joint bodies being pluggable and connected, a first concentric channel being formed between the joint body and the outer tube, a second concentric channel being formed between the joint body and the inner tube, the first concentric channel being arranged to be connected to the second fluid channel but not to the third fluid channel, and the second concentric channel being arranged to be connected to the third fluid channel but not to the second fluid channel.

[0011] Optionally, the diameter of the connector body is smaller than the diameter of the outer tube, and an end plate is provided at the non-plug-in end of the connector body, and an annular baffle is provided on the outer periphery of the connector body facing the side of the third fluid channel, and the outer periphery of the annular baffle is supported on the inner wall of the outer tube to separate the third fluid channel from the first concentric channel through the annular baffle.

[0012] Optionally, a communication hole is provided at a position of the end plate corresponding to the third fluid channel, and the third fluid channel is connected to the second concentric channel through the communication hole.

[0013] Optionally, the connection between the two plug bodies is sealed by a first sealing member.

[0014] Optionally, in the plug-in fit, the outer periphery of the inner joint body is provided with a first drain valve capable of connecting or cutting off the first concentric channel, and the inner joint body is located below the rod body. The first drain valve is configured to open when the two joint bodies are plugged in and to close when the two joint bodies are separated.

[0015] Optionally, the first drain valve includes a first valve seat provided on the inner wall of the outer tube and a first valve core provided on the inner wall of the first valve seat, the first valve core being slidably provided on the outer periphery of the joint body, and the thickness of the first valve core being greater than the thickness of the joint body, and is configured as follows:

[0016] When the two joint bodies are plugged in, the end of the outer joint body pushes the first valve core to move, so that the first valve core is separated from the first valve seat, and the first concentric channel is connected;

[0017] When the two joint bodies are separated, the first valve core is reset under the action of the first reset member, and the first concentric channel is disconnected.

[0018] Optionally, the inner tube has a corresponding first end and a second end, the second end of the inner tube is provided with a necked section that can be plugged into the first end of the inner tube, the necked section is located below the rod body, and the outer periphery of the necked section is provided with a second drain valve that can connect or cut off the second concentric channel, and the second drain valve is configured to open when the necked section is inserted into the first end of the inner tube, and close when the necked section is detached from the first end of the inner tube.

[0019] Optionally, the second drain valve includes a second valve seat provided on the inner wall of the joint body and a second valve core provided on the inner wall of the second valve seat, the second valve core being slidably provided on the outer periphery of the necked section, and the thickness of the second valve core being greater than the thickness of the first end of the inner tube, and is configured as follows:

[0020] When the narrowed section is inserted into the first end of the inner tube, the first end of the inner tube pushes the second valve core to move, so that the second valve core is separated from the second valve seat, and the second concentric channel is connected;

[0021] When the necked section is separated from the first end of the inner tube, the second valve core is reset under the action of the second reset member, and the second concentric channel is disconnected.

[0022] Optionally, a male connector and a female connector are provided at both ends of the outer tube, and the male connector and the female connector are threadedly connected.

[0023] Optionally, a first communication port for connecting the second fluid channel and the third fluid channel is provided on the partition.

[0024] Optionally, the outer pipe is provided with a second communication port for connecting the second fluid channel and the wellbore annulus, and / or

[0025] The outer pipe is provided with a third communication port for connecting the third fluid channel and the wellbore annulus.

[0026] Optionally, a plug for sealing the second fluid channel and the third fluid channel is provided at the end of the rod at the bottom.

[0027] The technical solution provided by the embodiments of the present invention has the following advantages compared with the prior art:

[0028] The multi-channel drill pipe provided by the present invention has an inner tube and an outer tube separated to form a multi-channel structure, which reduces the space occupied in the radial direction of the drill pipe and avoids affecting the use effect of the drill pipe. A concentric joint is provided between two adjacent drill pipes. By providing the concentric joint, the fluid in the second fluid channel at the top can only enter the second fluid channel at the bottom after passing through the first concentric channel. Correspondingly, the fluid in the third fluid channel at the top can only enter the third fluid channel at the bottom after passing through the second concentric channel. As a result, the fluid can flow in the corresponding fluid channel as needed during the transportation process, avoiding fluid crossflow and pressure interference caused by inconsistent flow channel alignment, and meeting the use requirements of the drill pipe. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0030] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0031] FIG1 is a schematic structural diagram of a rod body according to an embodiment of the present invention;

[0032] FIG2 is a cross-sectional view of a rod body according to an embodiment of the present invention;

[0033] FIG3 is a schematic structural diagram of the adaptively connected multi-channel drill pipe in a connected state according to an embodiment of the present invention;

[0034] FIG4 is a schematic structural diagram of an embodiment of the present invention in which the outer tube of the rod body is provided with a second communication port and a third communication port;

[0035] FIG5 is a schematic structural diagram of an embodiment of the present invention in which a plug is provided at the end of the rod body;

[0036] FIG6 is an enlarged view of a portion of the structure of FIG1 ;

[0037] FIG7 is an enlarged view of a portion of the structure of FIG3 .

[0038] Description of Reference Numerals

[0039] 1. Rod body; 11. Inner tube; 111. Neck section; 12. Outer tube; 121. Male connector; 122. Female connector; 123. Second communication port; 124. Third communication port; 13. First fluid channel; 14. Partition; 15. Second fluid channel; 16. Third fluid channel; 2. Concentric connector; 21. Connector body; 211. End plate; 212. Annular baffle; 213. Connecting hole; 22. First concentric channel; 23. Second concentric channel; 3. First drain valve; 4. Second drain valve; 5. Plug. DETAILED DESCRIPTION

[0040] In order to more clearly understand the above-mentioned objects, features and advantages of the present invention, the scheme of the present invention will be further described below. It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other.

[0041] The following description sets forth many specific details to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein; it is obvious that the implementation methods in the specification are only part of the implementation methods of the present invention, not all of the implementation methods.

[0042] As shown in Figures 1 to 7 , the adaptively connected multi-channel drill pipe provided in embodiments of the present invention includes multiple rod bodies 1 connected end-to-end. The end-to-end connection method between the multiple rod bodies 1 is not limited and can be designed according to actual needs. Rod body 1 includes a sleeved inner tube 11 and an outer tube 12. Specifically, outer tube 12 is sleeved around the outer circumference of inner tube 11, with the axes of outer tube 12 and inner tube 11 coinciding, and outer tube 12 and inner tube 11 spaced apart along the radial direction of inner tube 11. During operation, inner tube 11 does not bear the primary drilling load.

[0043] The inner tube 11 is hollow and open at both ends, forming a first fluid channel 13 in the middle of the inner tube 11. The first fluid channel 13 allows for the flow of the corresponding fluid. When two adjacent rod bodies 1 are connected, the inner tube 11 between the two rod bodies 1 can be plugged in to achieve communication with the first fluid channel 13. As shown in Figure 2, the inner tube 11 and the outer tube 12 are separated by two partitions 14 to form a second fluid channel 15 and a third fluid channel 16 between the inner tube 11 and the outer tube 12. Preferably, the two partitions 14 are symmetrically arranged along the axis of the inner tube 11 and extend radially along the inner tube 11 so that the cross-sectional areas of the second fluid channel 15 and the third fluid channel 16 are the same. In this case, the second fluid channel 15 and the third fluid channel 16 are semicircular flow channels with the same curvature. The partitions 14 are long straight plates and are connected to the inner tube 11 by welding, plugging, or integral casting. The length of the partition 14 can be set according to site requirements to separate the second fluid channel 15 from the third fluid channel 16. In this design, the design of the first fluid channel 13, the second fluid channel 15, and the third fluid channel 16 maximizes the use of the internal space of the rod body 1 while minimizing flow pressure loss, achieving an excellent balance between space utilization and energy utilization.

[0044] Partition 14 can completely separate second fluid channel 15 from third fluid channel 16 or partially separate second fluid channel 15 from third fluid channel 16, thereby achieving communication between second fluid channel 15 and third fluid channel 16. The design can be tailored to actual needs. Since the drill pipe is composed of multiple rod bodies 1, a partially isolated partition 14 can be used at the end of the drill pipe to allow fluid to reflux within the rod body 1.

[0045] The rod body 1 also includes a concentric joint 2, which includes a joint body 21 provided at both ends of the inner tube 11. The joint body 21 adopts a cylindrical structure, and the two joint bodies 21 can be plugged into each other. Specifically, the diameter of one joint body 21 is larger than the diameter of the other joint body 21, so that the end of the joint body 21 with a relatively smaller diameter can be inserted into the interior of the joint body 21 with a relatively larger diameter. At the same time, during the plug-in process of the two joint bodies 21, the two joint bodies 21 should be sealed to prevent the fluid from flowing out through the gap between the two joint bodies 21. The joint body 21 is connected to the inner tube 11 by welding, plugging, or integrally cast with the inner tube 11.

[0046] A first concentric channel 22 is formed between the connector body 21 and the outer tube 12, and a second concentric channel 23 is formed between the connector body 21 and the inner tube 11. The first concentric channel 22 is configured to communicate with the second fluid channel 15 but not with the third fluid channel 16. With this design, when two adjacent rod bodies 1 are connected, the first concentric channels 22 of the two connector bodies 21 flow, allowing fluid in the upper second fluid channel 15 to enter the first concentric channel 22, while fluid in the third fluid channel 16 cannot enter the first concentric channel 22. After filling the first concentric channel 22, the fluid in the first concentric channel 22 flows into the second fluid channel 15 of the lower rod body 1, rather than into the third fluid channel 16 of the lower rod body 1. Consequently, the fluid in the second fluid channel 15 of the upper rod body 1 can only enter the second fluid channel 15 of the lower rod body 1, but cannot enter the third fluid channel 16 of the lower rod body 1. That is, the fluid in the second fluid channel 15 of the upper rod body 1 will flow into the second fluid channel 15 of the lower rod body 1 through the outer periphery of the joint body 21 .

[0047] The second concentric channel 23 is configured to communicate with the third fluid channel 16 but not with the second fluid channel 15. With this design, when two adjacent rods 1 are connected, the second concentric channels 23 of the two connector bodies 21 flow freely. Fluid in the upper third fluid channel 16 can enter the second concentric channel 23, while fluid in the second fluid channel 15 cannot. After filling the second concentric channel 23, the fluid in the second concentric channel 23 flows into the third fluid channel 16 of the lower rod 1, preventing it from flowing into the second fluid channel 15 of the lower rod 1. Consequently, fluid in the third fluid channel 16 of the upper rod 1 can only enter the third fluid channel 16 of the lower rod 1, preventing it from entering the second fluid channel 15 of the lower rod 1. In other words, fluid in the third fluid channel 16 of the upper rod 1 flows through the interior of the connector body 21 into the third fluid channel 16 of the lower rod 1.

[0048] The multi-channel drill pipe provided by the present invention has an inner tube 11 and an outer tube 12 separated to form a multi-channel structure, which reduces radial space occupation of the drill pipe and avoids affecting the performance of the drill pipe. A concentric joint 2 is provided between two adjacent drill pipes. By providing the concentric joint 2, the fluid in the upper second fluid channel 15 can only enter the lower second fluid channel 15 after passing through the first concentric channel 22. Correspondingly, the fluid in the upper third fluid channel 16 can only enter the lower third fluid channel 16 after passing through the second concentric channel 23. This allows the fluid to flow through the corresponding fluid channels as needed during the delivery process, avoiding fluid crossflow and pressure interference caused by inconsistent flow channel alignment, meeting the use requirements of the drill pipe, and thus solving the problem of conventional drill pipes with multiple channels spaced apart along the circumferential direction. During installation, the multiple channels on two adjacent drill pipes cannot align, resulting in the inability of fluid to enter the corresponding channels, which affects the performance of the drill pipe. In addition, the provision of the concentric joint 2 realizes automatic alignment of the three flow channels, greatly improving ease of use and reducing on-site operation time and cost.

[0049] In addition, during deep well and ultra-deep well drilling operations, the resistance along the wellbore and drill tools increases due to the excessive drilling depth. The existing drilling pump operating capacity is difficult to meet the growing power required for downhole power drilling tools. At the same time, a single drilling fluid flow channel and power transmission system can no longer meet the needs of responding to complex downhole accidents and drilling in complex formations. The drill pipe provided in this application adopts a three-channel design. Without interfering with the conventional drilling fluid circulation system and performance, the drill pipe can provide an additional power source for drilling. By constructing an independent fluid-driven power channel, an independent power source is provided for downhole power drilling tools. At the same time, the burden of drilling pump operations is reduced, and on-site operators are assisted in solving various complex downhole problems such as well leakage and overflow, helping my country achieve high-level self-reliance in petroleum technology and equipment.

[0050] The drill pipe provided by the present invention adopts a multi-channel structure, wherein the additional power transmission flow channel provided can be used to drive the downhole tool, reducing the workload of the drilling pump. The activation and deactivation of the downhole tool can be independently controlled and adjusted by the additional power transmission flow channel, thereby improving the flexibility of drilling and completion operations.

[0051] In some embodiments, as shown in Figures 1, 3, 5, 6, and 7, the diameter of the connector body 21 is smaller than the diameter of the outer tube 12, and the connector body 21 and the outer tube 12 are coaxially arranged with a gap formed between the connector body 21 and the outer tube 12, thereby forming a first concentric channel 22 between the outer tube 12 and the connector body 21. An end plate 211 is provided at the non-inserted end of the connector body 21, which is the end of the connector body 21 away from the open end.

[0052] An annular baffle 212 is provided on the side of the outer periphery of the joint body 21 facing the third fluid channel 16. The plate surface of the annular baffle 212 is perpendicular to the axial direction of 21. The annular baffle 212 is only located within the arc range corresponding to the third fluid channel 16 and is not a complete (360-degree) ring. The outer periphery of the annular baffle 212 is supported on the inner wall of the outer tube 12, and the two sides of the annular baffle 212 are respectively connected to the two partitions 14. At this time, the end plate 211 and the end of the baffle are in the same plane, so that the third fluid channel 16 and the first concentric channel 22 are separated by the annular baffle 212. At this time, the side of the outer periphery of the joint body 21 facing the second fluid channel 15 will be connected to the second fluid channel 15, so that the fluid in the second fluid channel 15 can enter the first concentric channel 22 between the joint body 21 and the outer tube 12, that is, the second fluid channels 15 on the two adjacent rod bodies 1 can be connected through the first concentric channel 22. The connector body 21 in this design can effectively separate the first concentric channel 22 from the third fluid channel 16 , ensuring that the fluid can be transported along a preset direction.

[0053] In some embodiments, as shown in FIG. 1 and FIG. 3 to FIG. 5 , a communication hole 213 is provided at a position of the end plate 211 corresponding to the third fluid channel 16 , and the third fluid channel 16 is connected to the second concentric channel 23 through the communication hole 213 .

[0054] Under this design, since an annular baffle 212 is provided on the side of the outer periphery of the joint body 21 facing the third fluid channel 16, the third fluid channel 16 is separated from the first concentric channel 22 by the annular baffle 212. Therefore, the fluid in the third fluid channel 16 will only enter the second concentric channel 23 through the connecting hole 213, and then flow to the third fluid channel 16 of the drill rod below through the second concentric channel 23, so that the fluid in the third fluid channel 16 will not be mixed with the fluid in the second fluid channel 15 during the transportation between the rod bodies 1, ensuring that the transportation between the fluids meets the requirements.

[0055] In some embodiments, the connection between the two plug bodies is sealed by a first sealing member, thereby ensuring a sealing effect of the two plug bodies after being plugged in and avoiding fluid leakage.

[0056] Specifically, the end of the joint body 21 with a relatively small diameter can be inserted into the interior of the joint body 21 with a relatively large diameter. At this time, a first sealing groove is set on the outer periphery of the joint body 21 with a relatively small diameter. At this time, the first sealing member includes a sealing ring that is sleeved on the outer periphery of the first sealing groove, and the sealing ring can extend out of the first sealing groove along the radial direction of the joint body 21 so that the protruding end of the sealing ring can be supported on the inner wall of the joint body 21 with a relatively large diameter to ensure the sealing effect between the two joint bodies 21.

[0057] For further optimization, there are multiple first sealing grooves, and the multiple first sealing grooves are arranged at intervals along the axial direction of the joint body 21. In addition, there should also be multiple sealing rings, and a sealing ring is provided in each first sealing groove, so that the multiple sealing rings form a multi-level seal to meet the sealing requirements between the two joint bodies 21.

[0058] In some embodiments, during plug-in engagement, a first relief valve 3 is provided on the outer periphery of the inner connector body 21, capable of connecting or disconnecting the first concentric passage 22. The inner connector body 21 is located below the rod body 1, and the first relief valve 3 is configured to open when the two connector bodies 21 are plugged in and close when the two connector bodies 21 are separated. In this design, when the two connector bodies 21 are connected, the first relief valve 3 automatically opens, connecting the first concentric passage 22, thereby allowing the second fluid passages 15 on the two adjacent rod bodies 1 to communicate through the first concentric passage 22. When the two connector bodies 21 are separated, the first relief valve 3 automatically closes, disconnecting the first concentric passage 22. This prevents the fluid in the second fluid passage 15 from flowing out of the bottom of the rod body 1 after the rod body 1 is disassembled, thereby preventing the loss of annular fluid and contamination of the drilling platform and drilling fluid, thus protecting the drilling fluid performance and saving unnecessary drilling fluid performance adjustment time and mixing costs.

[0059] As a feasible embodiment, the first relief valve 3 includes a first valve seat provided on the inner wall of the outer tube 12 and a first valve core provided on the inner wall of the first valve seat. The first valve core is slidably provided on the outer periphery of the joint body 21, and the first valve core is always sealed with the outer periphery of the joint body 21 during the sliding process, and the thickness of the first valve core is greater than the thickness of the joint body 21. The first valve seat is a support base for the first relief valve 3, which can bear the force generated by the movement of the first valve core. The first relief valve 3 also includes a first outer shell, on which the first valve seat is provided. The first outer shell is a support shell for the first relief valve 3, protecting the first valve seat and the first valve core from damage due to impact loads. A channel for fluid circulation can be provided on the first outer shell, or the first outer shell can adopt a split structure to protect the first valve seat and the first valve core respectively. These are not restrictive.

[0060] When the two connector bodies 21 are plugged together, the end of the outer connector body 21 pushes the first valve core to move, causing the first valve core to disengage from the first valve seat, thereby connecting the first concentric channel 22. At this time, because the thickness of the first valve core is greater than that of the connector body 21, the fluid in the second fluid channel 15 can flow into the first concentric channel 22 through the gap between the outer periphery of the connector body 21 and the first valve seat.

[0061] When the two joint bodies 21 are separated, the first valve core is reset by the first reset member, disconnecting the first concentric channel 22. Specifically, when the two joint bodies 21 are separated, the first reset member applies a force toward the open end of the joint body 21 to the first valve core, enabling the first valve core to cooperate with the first valve seat to block the first concentric channel 22, preventing the fluid in the second fluid channel 15 from flowing out through the bottom of the rod body 1. The first reset member can be a first reset spring.

[0062] The inner tube 11 has a corresponding first end and a second end. Taking the direction shown in Figure 1 as an example, the first end of the inner tube 11 is the left end of the inner tube 11, and the second end of the inner tube 11 is the right end of the inner tube 11. The second end of the inner tube 11 is provided with a tapered section 111 that can be plugged into and connected to the first end of the inner tube 11. The tapered section 111 is located below the rod body 1. During the connection process of two adjacent rod bodies 1, the tapered section 111 at the second end of the inner tube 11 can be inserted into the first end of the inner tube 11 to achieve communication between the first fluid channels 13 on the two adjacent rod bodies 1.

[0063] A second relief valve 4, capable of connecting or disconnecting the second concentric passage 23, is provided on the outer periphery of the tapered section 111. The second relief valve 4 is configured to open when the tapered section 111 is inserted into the first end of the inner tube 11 and to close when the tapered section 111 is separated from the first end of the inner tube 11. With this design, when the two inner tubes 11 are plugged together, the second relief valve 4 automatically opens, connecting the second concentric passage 23 and thereby allowing the third fluid passages 16 on the two adjacent rod bodies 1 to communicate through the second concentric passage 23. When the two inner tubes 11 are separated, the second relief valve 4 automatically closes, disconnecting the second concentric passage 23. This prevents the fluid in the third fluid passage 16 from flowing out of the bottom of the rod body 1 after the rod body 1 is disassembled, thereby preventing the loss of annular fluid and contamination of the drilling platform and drilling fluid.

[0064] As a feasible embodiment, the second relief valve 4 includes a second valve seat disposed on the inner wall of the connector body 21 and a second valve core disposed on the inner wall of the second valve seat, wherein the second valve seat is disposed on the inner wall of the connector body 21 that is on the inner side during the plugging process, and the second valve core is slidably disposed on the outer periphery of the tapered section 111. The second valve core is always sealed with the outer periphery of the tapered section 111 during the sliding process, and the thickness of the second valve core is greater than the thickness of the first end of the inner tube 11. The second valve seat is the support base of the second relief valve 4 and can bear the force generated by the movement of the second valve core. The second relief valve 4 can also include a second outer shell, on which the second valve seat is disposed. The second outer shell is the support shell of the second relief valve 4 and protects the second valve seat and the second valve core from damage due to impact loads. The second outer shell can be provided with a channel for fluid circulation, or the second outer shell can adopt a split structure to protect the second valve seat and the second valve core respectively. These are not restrictive.

[0065] When the tapered section 111 is inserted into the first end of the inner tube 11, the first end of the inner tube 11 pushes the second valve core to move, causing the second valve core to disengage from the second valve seat, thereby connecting the second concentric channel 23. At this time, because the thickness of the second valve core is greater than the thickness of the first end of the inner tube 11, the fluid in the third fluid channel 16 can flow into the second concentric channel 23 through the gap between the outer periphery of the tapered section 111 and the second valve seat.

[0066] When the tapered section 111 is separated from the first end of the inner tube 11, the second valve core is reset under the action of the second reset member, and the second concentric channel 23 is disconnected. Specifically, when the tapered section 111 is separated from the first end of the inner tube 11, the second reset member applies a force toward the open end of the connector body 21, enabling the second valve core to cooperate with the second valve seat to block the second concentric channel 23, preventing the fluid in the second fluid channel 15 from flowing out through the bottom of the rod body 1. The second reset member can be a second reset spring.

[0067] In some embodiments, a male connector 121 and a female connector 122 are respectively provided at both ends of the outer tube 12, and the male connector 121 and the female connector 122 are threadedly connected, so that the outer tubes 12 on two adjacent rod bodies 1 can be threadedly connected through the male connector 121 and the female connector 122, thereby increasing the convenience of disassembly and assembly between the rod bodies 1.

[0068] Because the concentric joint 2 is provided between the rod bodies 1, after the two rod bodies 1 are threadedly connected, no matter to what angle the two rod bodies 1 are rotated, the fluid in the second fluid channel 15 on the upper rod body 1 can only flow into the second fluid channel 15 on the lower rod body 1 due to the action of the concentric joint 2. Correspondingly, the fluid in the third fluid channel 16 on the upper rod body 1 can only flow into the third fluid channel 16 on the lower rod body 1.

[0069] For further optimization, the male connector 121 and the female connector 122 should be appropriately thickened relative to the outer tube structure to protect the threads and improve the load-bearing capacity of the outer tube 12. The outer tube 12 is the primary load-bearing portion of the drill pipe, capable of withstanding various loads such as drilling torque, tensile and compressive loads, and external impacts, while protecting the integrity of the inner tube 11 and other components. The ends of the outer tube 12 are connected using common drill pipe thread types, such as trapezoidal threads, short round buckle threads, and other thread types.

[0070] The partition 14 is provided with a first communication port for connecting the second fluid channel 15 and the third fluid channel 16. The partition 14 under this design can realize the interchange of fluids in the second fluid channel 15 and the third fluid channel 16 to meet the use requirements of different scenarios. Among them, since the entire drill pipe is formed by connecting multiple rod bodies 1, it is possible to select a rod body 1 with a first communication port or a rod body 1 without a first communication port according to actual needs. The three flow channels of the rod body 1 under this design can be independently used as inflow or outflow channels, or can be combined to form a closed circulation flow channel, and a variety of flow forms can be constructed according to needs.

[0071] In some embodiments, as shown in FIG4 , the outer tube 12 is provided with a second communication port 123 for connecting the second fluid channel 15 with the wellbore annulus, and / or a third communication port 124 for connecting the third fluid channel 16 with the wellbore annulus. The second communication port 123 and the third communication port 124 enable communication between the second fluid channel 15 and the wellbore annulus or between the third fluid channel 16 and the wellbore annulus, thereby facilitating wellbore cleaning and meeting the requirements of different working conditions.

[0072] In some embodiments, as shown in Figures 4 and 5 , a plug 5 is provided at the lower end of the rod body 1 for blocking the second fluid channel 15 and the third fluid channel 16. The plug 5 can be used to block the second fluid channel 15 and the third fluid channel 16 at the end to prevent fluid from flowing out through the bottom end of the drill pipe, thereby meeting the requirements of different working conditions.

[0073] The rod body 1 provided in this application needs to be assembled and tested before use. The assembly procedure includes the following steps:

[0074] Step S1: Install the inner tube 11 in the outer tube 12, and connect or weld the partition 14 to the inner wall of the outer tube 12 to maintain a seal.

[0075] Step S2: Install the joint body 21 at both ends of the rod body 1 and keep it sealed. Specifically, the male concentric joint 2 of the joint body 21 is installed on one side of the male joint 121 of the rod body 1, and the female concentric joint 2 is installed on the side of the female joint 122 of the rod body 1.

[0076] Step S3, installing the first relief valve 3 and the second relief valve 4 on the rod body 1, ensuring that the first relief valve 3 and the second relief valve 4 automatically close when two adjacent rod bodies 1 are disconnected, blocking the leakage of fluid in the annular flow channel, and automatically open when the two rod bodies 1 are connected, correspondingly communicating the annular flow channel.

[0077] The installation process of the drill pipe provided in this application is as follows:

[0078] Step S1, formulate a drill pipe connection plan based on actual site needs, including whether it is necessary to select an inner tube 11 with a first communication port, whether it is necessary to select an outer tube 12 with a second communication port 123 and a third communication port 124, select a completely isolated partition 14 or a partially isolated partition 14, or use a partition 14 with a first communication port, etc.

[0079] Step S2: According to the drill pipe connection plan, select the appropriate inner pipe 11, outer pipe 12, concentric joint 2 and relief valve, assemble the drill pipe according to the on-site quantity requirements, and test the sealing performance of the drill pipe.

[0080] Step S3: Install corresponding sealing elements on the first sealing member on the inner tube 11, outer tube 12 and concentric joint 2 of the drill pipe, and distinguish and align the center lines of the male joint 121 and female joint 122 of the two drill pipes.

[0081] Step S4: Install two joint bodies 21 at both ends of the drill pipe respectively. During installation, the annular baffle 212 faces inward, and ensure that the sealing structure can achieve effective sealing.

[0082] Step S5, aligning the center line of the inner tube 11 to ensure that the plug-in connection structure can be smoothly inserted and that the sealing structure can achieve effective sealing.

[0083] Step S6, clean the threads on the outer tube 12, apply thread grease, align the center line of the outer tube 12, insert and connect the two ends of the inner tube 11, and rotate the outer tube 12 at the same time until the threaded connection of the outer tube 12 reaches the set make-up torque, and the connection is completed.

[0084] During use, corresponding fluids are injected into the first, second, and third fluid channels 13, 15, and 16, or portions thereof, according to the drill pipe connection scheme and site requirements. As the fluids pass through concentric joint 2, they are automatically diverted by concentric joint 2 and enter the corresponding fluid channels on the next rod 1. The fluids in the different channels flow along the designated flow paths. After fulfilling their design requirements, such as driving downhole power drilling tools, carrying cuttings, and assisting in handling complex downhole problems, they are then returned along the preset return path, based on the drill pipe connection scheme and the communication design between inner tube 11, outer tube 12, and partition 14.

[0085] By constructing a self-aligning concentric joint 2, the drill pipe achieves multi-channel injection downhole or closed circulation through the combination of partial channels. The drill pipe structure and connection method of the present invention can be used to construct a drill string and perform multi-channel driven drilling operations based on actual site needs. The use of this drill pipe can, to a certain extent, address the power transmission and flow pattern limitations of deep wells, ultra-deep wells, and complex formations. It also provides equipment support for my country's drilling and completion operations to address accidents such as well collapse, stuck pipe, well kicks, blowouts, and the coexistence of leaks and blowouts in complex formations.

[0086] The use of the drill rod provided in this application includes but is not limited to the following embodiments:

[0087] Example 1

[0088] The rod body 1 has three fluid flow channels: a first fluid channel 13 at the center of the inner tube 11, and a second fluid channel 15 and a third fluid channel 16 formed by the outer tube 12 and the inner tube 11. The drill pipe mainly consists of two types of rod bodies 1, each consisting of an inner tube 11, an outer tube 12, a concentric joint 2, and a relief valve. The total length is 9.6 meters.

[0089] The inner tube structure of the first and second types of rod bodies 1 mainly includes an inner tube 11 and two opposite partitions 14. The main body of the inner tube 11 is a Φ110mm long straight round tube, and the partitions 14 on both sides are long straight plates, which are cast as one piece with the inner tube 11. The partitions 14 adopt a complete isolation design to achieve complete isolation of the second fluid channel 15 and the third fluid channel 16. At this time, the partition 14 is not provided with a first communication port.

[0090] The outer tube structure of the first and second types of rod bodies 1 primarily includes a male connector 121, a female connector 122, and an outer tube 12. The male connector 121 and female connector 122 are conventional rod body 1 structures, but are appropriately thickened relative to the outer tube 12 to protect the threads and improve the load-bearing capacity of the outer tube 12. The ends of the outer tube 12 are connected using the long round threaded connections commonly used for conventional rod bodies 1. The outer tube 12 of the first type of rod body 1 does not have the second communication port 123 and the third communication port 124. The outer tube 12 of the second type of rod body 1 is provided with the second communication port 123 and the third communication port 124, and two plugs 5 are installed at the end of the male connector 121 of the rod body 1.

[0091] The concentric joints 2 of the first and second rod bodies 1 mainly consist of a joint body 21 and an annular baffle 212. The annular baffle 212 is a semi-circular plate (with an angle of 180 degrees) and is integrally cast with the joint body 21. A drain valve is installed at one end of the male joint 121.

[0092] The connection is performed during actual on-site use. The connection method includes the following steps:

[0093] Step S1 , according to the actual needs on site and the connection scheme of the rod body 1 , the inner tube 11 , the outer tube 12 , the concentric joint 2 and the drain valve of the two rod bodies 1 are installed according to the quantity requirements on site, and the sealing performance of the rod body 1 is tested.

[0094] Step S2: Install corresponding sealing elements on the sealing structures on the inner tube 11, outer tube 12 and concentric joints 2 of the two rod bodies 1, and distinguish and align the center lines of the male and female joints 122 of the two rod bodies 1.

[0095] Step S3, installing the joint body 21 at both ends of the two rod bodies 1, with the annular baffle 212 facing inward during installation, and ensuring that the sealing structure can achieve effective sealing;

[0096] Step S4, aligning the center lines of the inner tubes 11 of the two rod bodies 1 to ensure that the plug-in connection structure can be smoothly inserted and that the sealing structure can achieve effective sealing.

[0097] Step S5, clean the threads of the outer tubes 12 of the two rod bodies 1, apply thread grease, align the center lines of the outer tubes 12, insert and connect the two ends of the inner tube 11, and rotate the outer tube 12 at the same time until the threaded connection of the outer tube 12 reaches the set make-up torque.

[0098] Specifically, during connection, the second type of rod body 1 is used as the frontmost rod body 1 , and the first type of rod body 1 is sequentially connected behind the second type of rod body 1 .

[0099] During use, drilling fluid is simultaneously injected into the first fluid channel 13, the second fluid channel 15, and the third fluid channel 16. The drilling fluid in the first fluid channel 13 drives the downhole power drill after passing through the rod body 1, and returns to the wellbore annulus through the drill bit. The fluid in the second fluid channel 15 and the third fluid channel 16 on the left and right sides is automatically diverted under the action of the concentric joint 2 when passing through the concentric joint 2, and enters the corresponding fluid channel of the next rod body 1. After driving other downhole tools, it reaches the front end of the second rod body 1 and enters the wellbore annulus under the action of the second communication port 123 and the third communication port 124 of the plug 5 and the outer tube 12, assisting in wellbore cleaning, and returns to the wellhead together with the drilling fluid in the first fluid channel 13.

[0100] Example 2

[0101] The rod body 1 has three fluid flow channels: a first fluid channel 13 at the center of the inner tube 11, and a second fluid channel 15 and a third fluid channel 16 formed by the outer tube 12 and the inner tube 11. The drill pipe mainly consists of two types of rod bodies 1, each consisting of an inner tube 11, an outer tube 12, a concentric joint 2, and a relief valve. The total length is 9.6 meters.

[0102] The inner tube structure of the first and second types of rod bodies 1 mainly includes an inner tube 11 and two opposite partitions 14. The main body of the inner tube 11 is a Φ100mm long straight round tube, and the partitions 14 on both sides are long straight plates, which are cast integrally with the inner tube 11. The partitions 14 adopt a complete isolation design to achieve complete isolation of the second fluid channel 15 and the third fluid channel 16. The ribs of the second type of rod body 1 adopt a partial isolation design to achieve partial isolation and connection between the second fluid channel 15 and the third fluid channel 16. No communication ports are set on the partitions 14 of the two types of drill pipe ribs.

[0103] The outer tube structure of the first and second rod bodies 1 primarily comprises a male connector 121, a female connector 122, and an outer tube 12. The male connector 121 and female connector 122 are conventional rod body 1 structures, with appropriate thickness added to protect the threads and improve the load-bearing capacity of the outer tube 12. The ends of the outer tube 12 utilize trapezoidal threads, a common feature of conventional rod bodies 1. The outer tube 12 of the first and second rod bodies 1 lacks the second and third communication ports 123 and 124. The second rod body 1 has two plugs 5 installed at the male connector 121 end.

[0104] The concentric joints 2 of the first and second rod bodies 1 mainly include a joint body 21 and an annular baffle 212. The annular baffle 212 is a semi-circular plate, integrally cast with the joint body 21. The drain valve is installed at one end of the male joint 121.

[0105] The connection is performed during actual on-site use, and the connection method is consistent with the drill rod connection method in Example 1, and is not described in detail here.

[0106] During use, drilling fluid is injected into the first fluid channel 13, and driving fluid is injected into the second fluid channel 15. After passing through the drill pipe, the drilling fluid drives the downhole power drill and returns to the wellbore annulus through the drill bit. When the driving fluid in the second fluid channel 15 passes through the concentric joint 2, it is automatically diverted under the action of the concentric joint 2 and enters the second fluid channel 15 of the next drill pipe. After driving other downhole tools, it reaches the front end of the second drill pipe and enters the third fluid channel 16 on the right under the action of the plug 5 and part of the isolation baffle 14. It returns upward, and when passing through the concentric joint 2, it is automatically diverted under the concentric action and enters the third fluid channel 16 of the next drill pipe, and finally returns to the wellhead.

[0107] Example 3

[0108] The rod body 1 has three fluid flow channels: a first fluid channel 13 at the center of the inner tube 11, and a second fluid channel 15 and a third fluid channel 16 formed by the outer tube 12 and the inner tube 11. The drill pipe mainly consists of two types of rod bodies 1, each consisting of an inner tube 11, an outer tube 12, a concentric joint 2, and a relief valve. The total length is 9.6 meters.

[0109] The inner tube structure of the first and second types of rod bodies 1 mainly includes an inner tube 11 and two opposite partitions 14. The main body of the inner tube 11 is a Φ100mm long straight round tube, and the partitions 14 on both sides are long straight plates, which are cast integrally with the inner tube 11. The partitions 14 adopt a complete isolation design to achieve complete isolation of the second fluid channel 15 and the third fluid channel 16. At this time, the partition 14 is not provided with a first communication port.

[0110] The outer tube structure of the first and second rod bodies 1 primarily comprises a male connector 121, a female connector 122, and an outer tube 12. The male connector 121 and female connector 122 are conventional rod body 1 structures, with appropriate thickness added to protect the threads and improve the load-bearing capacity of the outer tube 12. The ends of the outer tube 12 utilize short round buckle threads, commonly used for rod bodies 1. Neither the second nor the second rod body 1 has a second communication port 123 or a third communication port 124 on the outer tube 12. The second rod body 1 does not have a plug 5 installed at the male connector 121 end.

[0111] The connection is performed during actual on-site use, and the connection method is consistent with the drill rod connection method in Example 1, and is not described in detail here.

[0112] During use, a wellbore annulus plugging tool or plugging fluid is installed at the wellhead or downhole, and drilling fluid is injected into the second fluid channel 15 and the third fluid channel 16. The drilling fluid passes through the rod body 1 and, when passing through the concentric joint 2, is automatically diverted by the concentric joint 2 and enters the corresponding flow channel of the next drill pipe. After driving other downhole tools, it reaches the front end of the second rod body 1 and enters the first fluid channel 13. After carrying rock cuttings to complete the wellbore cleaning, it finally returns to the wellhead along the first fluid channel 13.

[0113] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article, or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or device comprising the element.

[0114] The foregoing description is intended only to provide specific embodiments of the present invention, which will enable those skilled in the art to understand and implement the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not intended to be limited to the embodiments described herein, but is to be construed in the widest possible manner consistent with the principles and novel features disclosed herein.

Claims

1. An adaptive connected multi-channel drill pipe, characterized in that It includes a plurality of rod bodies (1) connected end to end. The rod body (1) includes a sleeved inner tube (11) and an outer tube (12). A first fluid passage (13) is formed in the middle of the inner tube (11). The inner tube (11) and the outer tube (12) are separated by two partition plates (14) to form a second fluid passage (15) and a third fluid passage (16) between the inner tube (11) and the outer tube (12). The rod body (1) further includes a concentric joint (2). The concentric joint (2) includes joint bodies (21) arranged at both ends of the inner tube (11). The two joint bodies (21) can be plugged and connected. A first concentric passage (22) is formed between the joint body (21) and the outer tube (12), and a second concentric passage (23) is formed between the joint body (21) and the inner tube (11). The first concentric passage (22) is arranged to communicate with the second fluid passage (15) and not with the third fluid passage (16), and the second concentric passage (23) is arranged to communicate with the third fluid passage (16) and not with the second fluid passage (15).

2. The adaptive connected multi-channel drill pipe according to claim 1, wherein The diameter of the joint body (21) is smaller than the diameter of the outer tube (12). An end plate (211) is provided at the non-plugging end of the joint body (21). An annular baffle (212) is provided on the outer periphery of the joint body (21) on the side facing the third fluid passage (16). The outer periphery of the annular baffle (212) is supported on the inner wall of the outer tube (12) to separate the third fluid passage (16) from the first concentric passage (22) through the annular baffle (212).

3. The adaptive connected multi-channel drill pipe according to claim 2, wherein A communication hole (213) is provided at the position of the end plate (211) corresponding to the third fluid passage (16). The third fluid passage (16) is communicated with the second concentric passage (23) through the communication hole (213).

4. The adaptive connected multi-channel drill pipe according to claim 1, wherein The connection part of the two plug bodies is sealed by a first seal.

5. The adaptive connected multi-channel drill pipe according to any one of claims 1 to 4, characterized in that, In the plug-in fit, a first drain valve (3) capable of communicating or cutting off the first concentric passage (22) is provided on the outer periphery of the inner joint body (21). The inner joint body (21) is located below the rod body (1). The first drain valve (3) is arranged to open when the two joint bodies (21) are plugged and close when the two joint bodies (21) are separated.

6. The adaptive connected multi-channel drill pipe according to claim 5, characterized in that The first drain valve (3) includes a first valve seat provided on the inner wall of the outer tube (12) and a first valve core provided on the inner wall of the first valve seat. The first valve core is slidably arranged on the outer periphery of the joint body, and the thickness of the first valve core is greater than the thickness of the joint body (21), and is configured as follows: When the two joint bodies (21) are plugged, the end of the outer joint body (21) pushes the first valve core to move, so that the first valve core disengages from the first valve seat, and the first concentric passage (22) is communicated; When the two joint bodies (21) are separated, the first valve core is reset under the action of the first reset member, and the first concentric channel (22) is disconnected.

7. The adaptive connected multi-channel drill pipe according to any one of claims 1 to 4, characterized in that The inner tube (11) has corresponding first and second ends. A reduced-diameter section (111) capable of being inserted and connected to the first end of the inner tube (11) is provided at the second end of the inner tube (11). The reduced-diameter section (111) is located below the rod body (1). A second drain valve (4) capable of communicating or blocking the second concentric channel (23) is provided on the outer periphery of the reduced-diameter section (111). The second drain valve (4) is arranged to open when the reduced-diameter section (111) is inserted into the first end of the inner tube (11) and to close when the reduced-diameter section (111) is separated from the first end of the inner tube (11).

8. The adaptive connected multi-channel drill pipe according to claim 7, characterized in that The second drain valve (4) includes a second valve seat provided on the inner wall of the joint body (21) and a second valve core provided on the inner wall of the second valve seat. The second valve core is slidably arranged on the outer periphery of the reduced-diameter section (111), and the thickness of the second valve core is greater than the thickness of the first end of the inner tube (11), and is configured as follows: When the reduced-diameter section (111) is inserted into the first end of the inner tube (11), the first end of the inner tube (11) pushes the second valve core to move, so that the second valve core is separated from the second valve seat, and the second concentric channel (23) is communicated; When the reduced-diameter section (111) is separated from the first end of the inner tube (11), the second valve core is reset under the action of the second reset member, and the second concentric channel (23) is disconnected.

9. The adaptive connected multi-channel drill pipe according to any one of claims 1 to 4, characterized in that, Male connectors (121) and female connectors (122) are respectively provided at both ends of the outer tube (12), and the male connectors (121) and the female connectors (122) are threadedly connected.

10. The adaptive connected multi-channel drill pipe according to any one of claims 1 to 4, characterized in that, A first communication port for communicating the second fluid channel (15) and the third fluid channel (16) is provided on the partition plate (14).

11. The adaptive connected multi-channel drill pipe according to any one of claims 1 to 4, characterized in that, A second communication port (123) for communicating the second fluid channel (15) and the wellbore annulus is provided on the outer tube (12), and / or A third communication port (124) for communicating the third fluid channel (16) and the wellbore annulus is provided on the outer tube (12).

12. The adaptive connected multi-channel drill pipe according to any one of claims 1 to 4, characterized in that, A plug (5) for blocking the second fluid channel (15) and the third fluid channel (16) is provided at the end of the rod body (1) located below.

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