Downhole drilling while drilling multiple activation bypass tool

Abstract

The application discloses a downhole while-drilling multi-time activation bypass tool, which comprises a detachably connected bypass assembly and a ball catcher assembly. The bypass assembly comprises a bypass shell, a transposition sliding sleeve, a reset spring, a positioning bolt and a ball seat. The outer wall of the transposition sliding sleeve is provided with two groups of adjusting groove groups which are arranged in a head-tail surrounding mode. The groove bodies are provided with a plurality of locking positions and a reversing inclined groove. The positioning bolt is clamped into the locking position to limit the displacement of the sliding sleeve. The ball seat is internally provided with a ball body breaking blade. The ball catcher assembly is provided with a ball storage and catching cylinder. During operation, the opening valve ball, the isolation ball and the reverse activation ball are thrown to pressurize and drive the transposition sliding sleeve to reverse along the groove track, so that three working conditions of normal drilling, bypass shunting and full bypass isolation can be switched, and the broken ball bodies are uniformly stored. The tool can repeatedly open and close the bypass in one drilling, greatly improves the annulus return speed to remove the rock debris bed, reduces the tripping frequency and drilling cost, and continuously protects the while-drilling precision instrument in the shunting mode. The structure reverses smoothly, the downhole operation is stable, and the tool is suitable for while-drilling plugging and hole cleaning operations in various complex deep wells.

Description

Technical Field

[0001] This invention belongs to the field of downhole tools technology for oil and gas well drilling, and specifically discloses a downhole drilling multiple activation bypass tool. Background Technology

[0002] As oil and gas exploration and development continues to expand into deep wells, highly deviated wells, and extended reach wells, the proportion of long, stable, and horizontal well sections is constantly increasing, leading to frequent occurrences of complex working conditions such as lost circulation and cuttings bed accumulation. Drilling bypass tools can achieve high-volume bypass operations by switching the drilling fluid circulation path. On the one hand, this increases the annular fluid discharge, quickly completing lost circulation plugging and cuttings removal operations; on the other hand, it diverts the drilling fluid, preventing high-flow-rate fluid from directly impacting precision drilling instruments such as the lower MWD / LWD, rotary steerable drill string, and screw drill string. It is a key supporting tool for ensuring drilling efficiency and protecting downhole equipment in complex well sections. Existing conventional drilling bypass tools mostly adopt an integrated structure, relying on ball dropping to achieve bypass opening and closing, and are widely used in various oil and gas well drilling and completion auxiliary operations.

[0003] Existing traditional drilling bypass tools have revealed three core shortcomings in long-term field application, creating a significant contradiction with the demand for efficient field operations: First, each tool can only be opened and closed once per well entry, and cannot switch bypass states multiple times. Under conditions of multi-stage leakage and repeated sand cleaning, frequent tripping to change tools and clean the reservoir cavity is necessary, limiting the number of opening and closing operations. Second, the circulation mode is singular, and the increase in annular return velocity is limited, making it difficult to quickly flush away thick cuttings beds, resulting in poor wellbore cleaning and easy to cause downhole failures such as dragging pressure and stuck pipe. Third, frequent tripping operations consume a large amount of non-productive time. The cost and cycle of tripping deep wells and extended reach wells are high, significantly increasing the comprehensive construction costs of labor, drilling rigs, and drilling fluids, resulting in low overall drilling efficiency. Summary of the Invention

[0004] To address the shortcomings of existing downhole bypass tools, such as limited opening and closing times, poor wellbore cleaning effect, low efficiency due to frequent tripping, and incompatibility with downhole precision instruments, this invention provides a downhole bypass tool that can be activated multiple times while drilling.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] A downhole drilling multiple activation bypass tool consists of two main parts: a bypass assembly and a detachable threaded ball catcher assembly. The bypass assembly includes a bypass housing, a shifting sleeve, a return spring, a positioning bolt, and a ball seat.

[0007] The bypass housing is a hollow tubular bearing base with nozzles on the side wall and an integrally formed annular step on the inner wall. An anti-loosening nut is threaded on the upper inner wall of the bypass housing. The anti-loosening nut is located above the shifting sleeve and is used to limit the upward movement limit of the sleeve to prevent the sleeve from derailing due to fluid impact. The annular step is used to support the return spring. The nozzle can cooperate with the bypass hole of the shifting sleeve to form a fluid bypass channel.

[0008] The core reversing component is the reversing sleeve, which is integrally formed with the large end and small end of the sleeve and can slide axially within the bypass housing. A bypass hole is opened on the side wall of the large end of the sleeve, and two sets of adjustment grooves that are connected end to end and surround the entire body 360° are machined on the outer wall. The adjustment grooves and positioning bolts are used to achieve bidirectional locking. The drilling fluid circulation path is switched by the misalignment / overlap of the bypass hole and the nozzle.

[0009] Furthermore, each set of adjustment channels has a circumferential span of 180°, and is internally arranged with parallel first long channel, first short channel, second short channel, and third short channel; adjacent channels are connected by forward and reverse inclined channels with an inclination angle of 45°, respectively, and the third short channel is connected to the first long channel of another set of adjustment channels through a second reverse inclined channel; each long and short channel is provided with a recessed locking position at its end.

[0010] Furthermore, the positioning bolt is threaded laterally onto the side wall of the bypass housing, with its end extending into the adjusting groove assembly. Engaging different locking positions simultaneously restricts the axial movement and circumferential rotation of the sliding sleeve, stably locking the working position. The 45° inclined groove ensures smooth, unobstructed reversal of the sliding sleeve, and the evenly distributed groove structure ensures uniform force distribution on the sliding sleeve, preventing localized wear. When the end of the positioning bolt is engaged in the upper locking position of the first short groove, the bypass hole and nozzle completely overlap, maximizing the bypass flow area and meeting the needs of high-volume well flushing and leak sealing.

[0011] The reset spring is fitted on the outside of the small end of the slide sleeve, with its two ends abutting against the lower end face of the large end of the slide sleeve and the annular step of the housing, respectively. A high-load-bearing disc spring structure is selected. When the slide sleeve moves downward, the spring is compressed to store energy. After the drill string is depressurized, the spring rebounds, driving the slide sleeve to accurately return to the corresponding locking position.

[0012] The ball seat is fixedly installed inside the large end of the sliding sleeve, below the bypass hole. The whole body includes the seat body, and the center of the seat body has a through fluid flow channel. The inner wall of the flow channel is circumferentially inlaid with hard alloy ball breaking blades. The shearing pressure is calibrated before leaving the factory. It can smoothly shear the valve opening ball, isolation ball, and deactivation ball under the preset pressure. After the pressure is released, the broken balls fall and are collected by their own weight.

[0013] The ball catcher assembly consists of a ball catcher housing and an internal ball catcher tube. The upper end of the ball catcher housing and the lower end of the bypass housing are threaded and sealed together. The detachable structure facilitates disassembly and cleaning after tripping out of the well. The ball catcher tube has ample ball storage space, which can accommodate all the ball debris generated by multiple ball throws. It is not limited by the number of times the bypass is opened and closed, thus avoiding debris falling downhole and causing water blockage or stuck drill bit failure.

[0014] Compared with the prior art, the present invention has the following beneficial effects:

[0015] (1) A multi-stage reversing locking structure is formed by using a bypass housing, a shifting sleeve, a reset spring, a positioning bolt, and a ball seat in conjunction with two sets of closed-loop surrounding adjustment grooves. It is equipped with a detachable large-capacity ball catcher assembly to store broken balls, thus realizing the unlimited opening and closing of the bypass channel during a single well entry of the tool. This eliminates the need for frequent drilling to clean the balls and replace the drill string, solving the problem of limited opening and closing times for traditional tools.

[0016] (2) The structural design of fully opening the bypass flow channel when the sliding sleeve bypass hole and the shell nozzle are completely overlapped, and diverting most of the drilling fluid directly into the annulus, has greatly improved the annulus fluid return velocity. Relying on the high-speed fluid to forcefully flush the long stable inclined section and horizontal section to deposit cuttings bed, the risk of stuck drill and dragging downhole failure is reduced, and wellbore cleaning and drilling plugging operations are completed efficiently. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the overall structure of this tool;

[0018] Figure 2 This is a schematic diagram of the explosion of this tool;

[0019] Figure 3 This is a cross-sectional view of the tool;

[0020] Figure 4 This is a schematic diagram of the structure of the large end of the sliding sleeve;

[0021] Figure 5 This is a schematic diagram of the adjustment channel assembly laid out flat.

[0022] Figure 6 This is a schematic diagram of the ball seat structure;

[0023] In the diagram, the correspondence between component names and drawing numbers is as follows:

[0024] 1-Bypass housing, 2-Ball catcher housing, 3-Shifting sleeve, 5-Reset spring, 6-Positioning bolt, 7-Adjusting groove assembly, 8-Ball catcher tube, 9-Ball seat, 10-Nozzle, 11-Anti-loosening nut, 12-Step, 30-Bypass hole, 31-Large end of sleeve, 32-Small end of sleeve, 700-Locking position, 71-First long groove, 72-First forward inclined groove, 73-First short groove, 74-First reverse inclined groove, 75-Second short groove, 76-Second forward inclined groove, 77-Third short groove, 78-Second reverse inclined groove, 91-Seat body, 92-Flow channel, 93-Ball breaking blade. Detailed Implementation

[0025] The embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and should not be construed as limiting the scope of the invention.

[0026] Example:

[0027] like Figures 1-6 As shown, a downhole drilling multiple activation bypass tool is composed of two parts: a bypass assembly and a ball catcher assembly. The lower ends of the ball catcher assembly and the bypass assembly are connected by a threaded detachable seal.

[0028] The bypass housing 1 is integrally machined from a high-strength, thick-walled alloy steel pipe, forming a hollow tubular load-bearing base. Two sets of nozzles 10 are opened along the upper sidewall of the bypass housing 1, serving as bypass discharge channels for drilling fluid. An annular step 12 is integrally machined into the inner wall of the bypass housing 1, with a flat end face to axially support the return spring 5. Internal threads are machined on the upper part of the inner wall of the bypass housing 1, and anti-loosening nuts 11 are screwed onto these threads. The anti-loosening nuts 11 are positioned above the transposition sleeve 3, and their lower end face forms the upper limit limiting surface of the transposition sleeve 3, preventing high-pressure fluid impact from causing the transposition sleeve 3 to slide upwards and derail, ensuring long-term stable operation of the reversing structure. External threads are machined on the lower outer wall of the bypass housing 1 for threaded sealing connection with the ball catcher housing 2. A metal sealing ring is added to the threaded mating surface to prevent drilling fluid leakage.

[0029] The shifting sleeve 3 is integrally forged and is fixedly connected as a whole by the large end 31 and the small end 32 of the sleeve, and can slide freely along the axial direction inside the bypass housing 1. A through-type bypass hole 30 is opened on the upper side wall of the large end 31 of the sleeve, and the number and flow area of ​​the bypass holes 30 are matched one by one with the nozzles 10 of the bypass housing 1.

[0030] Two sets of adjusting grooves 7 are milled on the outer wall of the large end 31 of the sliding sleeve. The two sets of adjusting grooves 7 are connected end to end, forming a 360° closed-loop reversing track around the outer wall of the large end 31 of the sliding sleeve. The circumferential span of a single set of adjusting grooves 7 is 180°. Inside a single set of adjusting grooves 7, four grooves are arranged in parallel: the first long groove 71, the first short groove 73, the second short groove 75, and the third short groove 77. The four grooves evenly divide the 180° circumferential span, so that the reciprocating sliding of the reversing sliding sleeve 3 is evenly stressed, avoiding local stress concentration and wear on the adjusting grooves 7. The grooves are connected by inclined grooves. The first long groove 71 and the first short groove 73 are connected by the first forward inclined groove 72. The first short groove 73 and the second short groove 75 are connected by the first reverse inclined groove 74. The second short groove 75 and the third short groove 77 are connected by the second forward inclined groove 76. The third short groove 77 and the first long groove 71 of another adjusting groove group 7 are connected by the second reverse inclined groove 78. The inclination angle of all forward and reverse inclined grooves is uniformly set to 45°. The reversing sliding process of the switching sleeve 3 is smooth and without jamming. The reversing action is sensitive when the ball is thrown and pressure is applied.

[0031] A recessed locking position 700 is provided at the lower end of the first long groove 71, the upper end of the first short groove 73, the lower end of the second short groove 75, and the upper end of the third short groove 77. A positioning bolt 6 is radially threaded onto the side wall of the bypass housing 1. The end of the positioning bolt 6 extends into the interior of the adjusting groove group 7 and can be engaged in any locking position 700, simultaneously restricting the axial movement and circumferential rotation of the shifting sleeve 3, and stably locking each cycle condition. When the end of the positioning bolt 6 is engaged in the locking position 700 at the upper end of the first short groove 73, the bypass hole 30 on the side wall of the large end 31 of the sleeve is completely radially aligned with the nozzle 10 of the bypass housing 1, and the bypass flow area reaches its maximum value, meeting the needs of large-volume well washing and leak sealing construction.

[0032] The return spring 5 is a multi-layered stacked disc spring combination, which is fully fitted on the outside of the small end 32 of the sliding sleeve. The upper end face of the return spring 5 is in close contact with the lower end face of the large end 31 of the sliding sleeve, and the lower end face of the return spring 5 is completely in contact with the annular step 12 inside the bypass housing 1. When the shifting sliding sleeve 3 is pushed downward by the high pressure of the drilling fluid, the return spring 5 is compressed and stores elastic potential energy. After the internal pressure of the drill string is released, the disc spring rebounds to provide stable thrust, pushing the shifting sliding sleeve 3 upward to the corresponding locking position 700 to complete the gear locking.

[0033] The ball seat 9 is fixed inside the large end 31 of the sliding sleeve by interference fit, and the installation position of the ball seat 9 is directly below the bypass hole 30. The ball seat 9 includes a seat body 91, and a through fluid flow channel 92 is opened in the center of the seat body 91. Multiple hard alloy ball breaking blades 93 are embedded circumferentially on the inner wall of the flow channel 92. The ball breaking blades 93 have high hardness and are resistant to drilling fluid erosion. Before the tool leaves the factory, the shear critical pressure is uniformly pressure tested and calibrated. The ball breaking blades 93 can smoothly shear the valve opening ball, isolation ball, and deactivation ball under the preset pressure, without the problem of premature ball breakage or damage to the drill string due to excessive pressure. The debris formed after the ball breaks falls downward by its own weight and is collected in the ball catcher assembly below.

[0034] The ball catcher assembly includes a ball catcher housing 2 and a built-in hollow cylindrical ball catcher tube 8. The upper end of the ball catcher housing 2 is machined with internal threads, which are sealed and matched with the lower end of the bypass housing 1 with external threads. The whole assembly is detachable, and the ball catcher housing 2 can be quickly disassembled after tripping in the drill string to remove the ball catcher tube 8 and clean the internal ball debris. The ball catcher tube 8 has a sufficient ball storage capacity to accommodate all the ball debris generated by multiple ball dropping and shearing operations, and is not limited by the number of times the bypass is opened and closed. It can effectively prevent ball debris from falling to the lower drill bit and screw drill bit, avoiding water hole blockage and stuck drill bit failures.

[0035] The workflow of this tool is as follows:

[0036] When the drilling tools are initially lowered into the well without any functional balls being deployed, the end of the positioning bolt 6 engages with the lower locking position 700 (point A) of the first long groove 71. The return spring 5 extends naturally, and the shifting sleeve 3 remains at its upper limit position. The bypass hole 30 at the large end 31 of the sleeve is completely misaligned and sealed with the nozzle 10 of the bypass housing 1, thus closing the bypass channel. All drilling fluid is transported downwards through the central flow channel of the shifting sleeve 3, passing through the flow channel 92 of the ball seat 9 and the ball catcher assembly, flowing downwards to the drill string assembly, drilling instruments, and drill bit, maintaining the normal drilling circulation.

[0037] The valve ball is deployed to open the bypass diversion condition. The valve ball is deployed at the wellhead and falls along the inner hole of the drill string to sit above the flow channel 92 of the ball seat 9, blocking the central flow channel. The pump is continuously started to pressurize, and the high-pressure fluid pushes the displacement sleeve 3 downward to compress the reset spring 5. The positioning bolt 6 slides along the first long groove 71 and slides into the upper locking position 700 (point B) of the first short groove 73 through the first positive inclined groove 72 at a 45° angle to complete the locking.

[0038] After the pressure rises to the preset shear value, the ball breaking edge 93 shears open the valve ball, and the debris falls into the ball catcher 8. The pressure inside the drill string is released, and the return spring 5 rebounds to lock the opening position of the switching sleeve 3. At this time, the positioning bolt 6 slides along the first short groove 73, slides through the first 45° reverse inclined groove 74 into the lower locking position 700 (point C) of the second short groove 75 to complete the locking. At this time, the bypass hole 30 and the nozzle 10 are completely aligned and connected. Most of the drilling fluid is discharged into the annulus through the bypass channel to increase the return speed to flush out rock cuttings and plug leaks. A small amount of fluid flows down along the central channel to cool and protect the lower precision instruments.

[0039] Drop the isolation ball. With the bypass open in the full bypass isolation condition, drop the isolation ball to block the central flow channel 92 of the ball seat 9. Then drop two deactivation balls to block the bypass hole 30 at the large end 31 of the sliding sleeve. Re-establish high pressure in the drill string. The shifted sliding sleeve 3 moves down slightly. The positioning bolt 6 slides along the second short groove 75 and slides into the upper locking position 700 (point D) of the third short groove 77 after passing through the second positive inclined groove 76. The central flow channel 92 is completely blocked. At this time, the bypass hole 30 and the nozzle 10 are misaligned and closed.

[0040] When the pressure reaches the shear threshold, the ball seat 9 synchronously shears and activates the ball, and all the debris is collected in the ball catcher 8. At this time, the return spring 5 rebounds and pushes the shifting sleeve 3 back to the initial position, and the positioning bolt 6 returns to the lower end of the first long groove 71 at the locking position 700 (point A) along the third short groove 77 and the second reverse inclined groove 78, and the drilling fluid resumes normal drilling circulation in the full center channel.

[0041] The repeated activation relies on two sets of 360-degree closed-loop adjustment grooves 7, with positioning bolts 6 that can cyclically switch all locking positions 700. During a single drilling operation, valve opening balls, isolation balls, and deactivation balls can be repeatedly deployed, allowing for unlimited opening and closing of the bypass channel. There is no need to clean the balls or change tools midway through drilling, thus fully realizing the core function of multiple opening and closing during a single well entry.

[0042] The embodiments of the present invention are given for illustrative and descriptive purposes only, and are not intended to be exhaustive or to limit the invention to the forms disclosed. Many modifications and variations will be apparent to those skilled in the art. The embodiments were chosen and described in order to better illustrate the principles and practical application of the invention, and to enable those skilled in the art to understand the invention and to design various embodiments with various modifications suitable for a particular purpose.

Claims

1. A downhole bypass tool that can be activated multiple times while drilling, characterized in that: Includes a bypass assembly and a ball catcher assembly detachably mounted therewith; the bypass assembly includes A bypass housing (1) is provided with a nozzle (10) on the upper side wall of the bypass housing (1) and a step (12) is provided on the inner wall of the bypass housing (1). The shifting sleeve (3) is slidably disposed in the bypass housing (1); the shifting sleeve (3) is composed of a fixedly connected large end (31) and a small end (32); a bypass hole (30) is provided on the upper side wall of the large end (31); an adjustment groove group (7) is engraved on the outer wall of the large end (31). The return spring (5) is sleeved on the small end (32) of the sliding sleeve. One end of the return spring (5) abuts against the large end (31) of the sliding sleeve, and the other end abuts against the step (12) of the bypass housing (1). A positioning bolt (6) is screwed onto the bypass housing (1); the end of the positioning bolt (6) is located in the adjusting groove group (7); The ball seat (9) is located inside the large end (31) of the sliding sleeve, below the bypass hole (30); The adjustment groove group (7) is configured in two groups, which are connected end to end and arranged around the outer wall of the large end (31) of the sliding sleeve; the adjustment groove group (7) includes a first long groove (71), a first short groove (73), a second short groove (75) and a third short groove (77) arranged in parallel. A first positive inclined groove (72) is provided between the first long groove (71) and the first short groove (73); A first reverse inclined groove (74) is provided between the first short groove (73) and the second short groove (75); A second positive inclined groove (76) is provided to connect the second short groove (75) and the third short groove (77); A second reverse inclined groove (78) is provided between the third short groove (77) and the first long groove (71) in another adjusting groove group (7). Locking positions (700) are respectively provided at the lower end of the first long groove (71), the upper end of the first short groove (73), the lower end of the second short groove (75), and the upper end of the third short groove (77).

2. The downhole drilling multi-activation bypass tool according to claim 1, characterized in that: The span of a single adjustment slot group (7) is 180°; the span of a single adjustment slot group (7) is equally divided among the first long slot (71), the first short slot (73), the second short slot (75) and the third short slot (77).

3. The downhole drilling multi-activation bypass tool according to claim 1, characterized in that: The first forward inclined groove (72), the first reverse inclined groove (74), the second forward inclined groove (76), and the second reverse inclined groove (78) have an inclination angle of 45°.

4. The downhole drilling multi-activation bypass tool according to claim 1, characterized in that: When the end of the positioning bolt (6) is in the locking position (700) of the second short groove (75), the bypass hole (30) coincides with the nozzle (10).

5. A downhole bypass tool that can be activated multiple times while drilling, as described in claim 1, characterized in that: The bypass housing (1) is also threaded with an anti-loosening nut (11), which is located above the shifting sleeve (3).

6. The downhole drilling multi-activation bypass tool according to claim 1, characterized in that: The ball catcher assembly includes a ball catcher housing (2) and a ball catcher tube (8) built into the ball catcher housing (2); the ball catcher housing (2) is threadedly connected to the lower end of the bypass housing (1).

7. The downhole drilling multi-activation bypass tool according to claim 1, characterized in that: The ball seat (9) includes a seat body (91), a flow channel (92) is provided in the middle of the seat body (91), and a ball breaking blade (93) is provided on the inner wall of the flow channel (92).

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