Differential multi-stage hydraulic control valve

Abstract

The differential multi-stage hydraulic control valve comprises an inner sleeve capable of moving axially, and a sliding block and a check block are arranged on the outer wall of the inner sleeve. A steering sleeve is sleeved outside the inner sleeve, and a steering pin and a plurality of steps are arranged on the inner wall of the steering sleeve; a control sleeve is arranged between the outer wall of the inner sleeve and the inner wall of the steering sleeve, an inner sliding groove and an outer sliding groove are formed in the inner wall and the outer wall of the control sleeve respectively, the inner sliding groove is in a wavy shape, and the outer sliding groove is in a reverse wavy shape. The inner sleeve is driven to move up and down in the axial direction, the sliding block drives the control sleeve to rotate by an angle in the circumferential direction through the inner sliding groove, the outer sliding groove drives the steering sleeve to reversely rotate by another angle in the circumferential direction through the steering pin, and the step rotates by the difference value of the two angles relative to the circumferential direction of the check block and is switched to the next step. Differential control over the angle is achieved through the reverse wavy shape of the inner sliding groove and the outer sliding groove, more liquid flow gears can be set, the gear selection of more than 20 levels can be achieved, and the higher requirement for a multi-production-layer well is met.

Description

Technical Field

[0001] This invention relates to a flow control device for intelligent well completion tubing, specifically a differential multi-stage hydraulic control valve. Background Technology

[0002] In multi-layered water-drive reservoirs, the interlayer imbalance intensifies with increasing water cut, leading to severe ineffective water circulation. Current conventional wireline retrieval techniques suffer from numerous problems, including low success rates in deploying and adjusting plugs, high workload for testing and deployment, and inability to monitor downhole flow rates in real time. Therefore, the demand for precise and efficient water injection well water cut control measures and optimized water cut management in oil wells is growing rapidly.

[0003] With the continuous advancement of digitalization and automation technologies, smart well completion technology will be able to more accurately optimize production and reduce costs, providing the oil and gas industry with more efficient, innovative, and sustainable solutions. Smart well completion incorporates permanent downhole sensors and surface-controlled downhole flow control valves, enabling real-time monitoring, evaluation, and proactive management of production (or injection) without any well intervention. Data is transmitted to the surface for local or remote monitoring on a digital well platform, increasing well production.

[0004] Downhole fluid control is a key technology in intelligent well completion systems, mainly including flow control valves for different formations and packers. With the development of multi-layered oil wells, the requirements for the number of production formations controlled by flow control valves are increasing. Currently, conventional flow control valves have fewer than 10 settings, which is insufficient to meet the growing new requirements. Summary of the Invention

[0005] To address the existing problems, this invention aims to provide a differential multi-stage hydraulic control valve designed based on the differential principle to meet the needs of multi-layer operations.

[0006] To achieve the above objectives, the technical solution adopted in this invention includes a valve body, which comprises an upper cylinder, an outer cylinder, a sealing cylinder, and a lower cylinder connected in sequence. The valve body has an axially movable inner sleeve inside, and a slider and a stop are provided on the outer wall of the middle section of the inner sleeve. A steering sleeve is fitted outside the inner sleeve, and the inner wall of the steering sleeve has a steering pin and several stepped steps arranged circumferentially to form an axial drop. A control sleeve is provided between the outer wall of the inner sleeve and the inner wall of the steering sleeve. The inner and outer walls of the control sleeve are respectively provided with concentric internal and external sliding grooves, the internal sliding groove being wavy and the external sliding groove being wavy in the opposite direction (such as serrated).

[0007] During use, the inner sleeve moves up and down along the axis. The slider of the inner sleeve drives the control sleeve to rotate circumferentially by an angle through the internal slide groove. The external slide groove of the control sleeve drives the steering sleeve to rotate circumferentially in the opposite direction by another angle through the steering pin. The circumferential rotation angle of the step of the steering sleeve relative to the stop of the inner sleeve is the difference between the two angles mentioned above, and it contacts the corresponding next step, that is, it switches to the next gear.

[0008] The internal slide groove of the control sleeve includes several inner upper end grooves and inner lower end grooves distributed at intervals along the circumference, and an inner guide groove that connects the inner upper end grooves and inner lower end grooves and is used to guide switching and drive the control sleeve to rotate circumferentially.

[0009] The outer groove of the control sleeve includes several outer upper end grooves and inner lower end grooves that are distributed circumferentially and extend upward along the axial direction, and an outer guide groove that connects the outer upper end grooves and outer lower end grooves and is used to guide the switching and drive the steering sleeve to rotate in the opposite direction.

[0010] The inner and outer guide grooves are several straight grooves arranged obliquely along the circumference, and the inclination directions of the corresponding inner and outer guide grooves are opposite to each other.

[0011] There is an angular difference between the central angle between the center lines of adjacent upper outer grooves and the central angle between the center lines of adjacent lower inner grooves.

[0012] The outer upper end groove and the inner lower end groove have different numbers and are evenly distributed along the circumference.

[0013] The inner lower end has six slots, and the outer upper end has eight slots. Each time a gear is changed, the step rotates 15° relative to the stop block, and one rotation of the step corresponds to 24 gears.

[0014] Among the various outer upper slots, there is an upper long slot corresponding to the fully closed state, and the length of the upper long slot extending upwards axially is greater than that of the other short slots; several stepped platforms are provided with lower long slots corresponding to the fully closed state. Initially, the steering pin is located at the upper end of the upper long slot and the stop block is located at the lower end of the lower long slot; during use, the inner sleeve moves upwards, the steering pin enters the outer guide slot along the upper long slot, and at the same time the stop block moves upwards along the lower long slot and disengages from it; as the gear shift is completed, the steering pin enters the short slot and the stop block contacts the next stepped platform.

[0015] The ends of the outer upper end groove, inner lower end groove, and outer upper end groove or outer lower end groove are provided with transition fillets. The connection between the inner guide groove and the inner upper end groove or inner lower end groove is provided with transition fillets.

[0016] The connection between the outer guide groove and the outer upper end groove and the outer lower end groove is provided with a transition fillet.

[0017] The steering sleeve has bearing assemblies at both ends.

[0018] It also includes a stepped cylinder, the upper end of which is connected to the lower end of the steering sleeve, and the inner wall of the stepped cylinder is provided with several steps along the circumferential direction.

[0019] The upper end of the stepped cylinder is connected to the lower end of the steering sleeve through a groove / protrusion structure, so that the steering sleeve and the stepped cylinder rotate synchronously.

[0020] The inner sleeve has a sealing assembly between the outer wall of the upper section and the inner wall of the valve body. The upper and lower parts of the sealing assembly are connected to the upper pressure transmission hole and the lower pressure transmission hole, respectively. The pressure of the upper pressure transmission hole and the lower pressure transmission hole pushes the inner sleeve to move downward and upward, respectively.

[0021] There is an angular difference between the slider and the stop in the circumferential direction.

[0022] The inner sleeve has slots for displacement tools at both ends.

[0023] The valve body has a through-hole fluid inlet on the lower side wall, and the inner sleeve has a flow channel on the lower side wall that communicates with the fluid inlet. Sealing components are installed between the outer wall of the inner sleeve above and below the flow channel and the inner wall of the valve body, forming a sealing structure. The flow channel and fluid inlet are adjusted by moving the inner sleeve up and down, thereby controlling the downhole fluid.

[0024] The sealing assembly is a Glyd ring, a V-shaped seal assembly, or an O-ring assembly.

[0025] Compared with existing technologies, this invention achieves differential angle control by using the reverse wave-like arrangement of the internal and external sliding grooves of the control sleeve to realize the reverse rotation of the inner sleeve and the stepped cylinder. This allows for more flow control levels to be set within a valve body of the same diameter, easily achieving more than 20 levels of selectable levels. This increases the number of flow control levels and overcomes the problem of insufficient control of the number of producing layers by existing flow control valves, meeting the higher requirements for wells with multiple producing layers. Furthermore, it has a simple structure, high pressure resistance, reliable sealing, and is easy to manufacture, resulting in lower costs. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the structure of an embodiment of the present invention.

[0027] Figure 2a This is a schematic diagram of the inner sleeve.

[0028] Figure 2b This is a sectional view of the inner sleeve.

[0029] Figure 3a This is a schematic diagram of the control sleeve and internal sliding groove.

[0030] Figure 3b This is a schematic diagram of the control sleeve and the external slide.

[0031] Figure 4 This is a schematic diagram of the stepped tube structure.

[0032] Figure 5 This is a schematic diagram showing the initial state of the slider and stop after assembly in an embodiment of the present invention.

[0033] Figure 6 This is a schematic diagram of the state when the device is closed according to an embodiment of the present invention.

[0034] Figure 7 This is a schematic diagram of the state during the transition in an embodiment of the present invention.

[0035] Figure 8 This is a schematic diagram of the state when the present invention is in gear 1.

[0036] In the diagram: 1 Upper cylinder, 2 Glyd ring, 3 Outer cylinder, 4 V-type seal assembly, 5 Bearing assembly, 6 Steering sleeve, 7 Stepped cylinder, 8 Steering pin, 9 Control sleeve, 11 Inner sleeve, 12 Sealing cylinder, 13 Lower cylinder, 21 Upper pressure transmission hole, 22 Lower pressure transmission hole, 23 Slider, 24 Stop, 25 Internal groove, 26 External groove, 27 Flow groove, 28 Stepped step, 29 Protrusion, 30 Inner short inclined side, 31 Inner long inclined side, 32 Inner lower end groove, 33 Outer upper end groove, 34 Outer long inclined side, 35 Outer short inclined side, 36 Transition fillet. Detailed Implementation

[0037] To make the objectives, technical solutions, and effects of this invention clearer, the invention will be further described below with reference to the accompanying drawings. For ease of description, the following will refer to... Figure 1 The direction of the upper and middle cylinders is "up" and the direction of the lower cylinders is "down".

[0038] See Figure 1 , Figure 1 The illustration shows an embodiment of the differential multi-stage hydraulic control valve of the present invention, including a valve body. The external structure of the valve body includes an upper cylinder, an outer cylinder, a sealing cylinder, and a lower cylinder connected in sequence. See also... Figure 2a The valve body has an inner sleeve that can move axially up and down. A Glyd ring and a V-shaped seal assembly are sequentially arranged between the outer wall of the upper section of the inner sleeve and the inner wall of the outer cylinder of the valve body. The outer wall of the inner sleeve and the inner wall of the outer cylinder form a hydraulic chamber. The upper and lower side walls of the outer cylinder of the V-shaped seal assembly have through-holes for upper and lower pressure transmission, respectively, which are connected to pressurization lines. Pressurizing the hydraulic chambers on the upper and lower sides of the V-shaped seal assembly through the upper and lower pressure transmission holes pushes the inner sleeve axially downward and upward, respectively.

[0039] See Figure 2aThe outer wall of the middle section of the inner sleeve is provided with a slider and a stop. The slider is used to contact the internal groove, and the stop is used to contact the step. The slider and the stop can be integrated with the body of the inner sleeve or they can be separate; in this embodiment, an integrated structure is adopted.

[0040] As a preferred option, see Figure 2b In this embodiment, there is an angular difference between the slider and the stop in the circumferential direction; see [link / reference]. Figure 1 The inner sleeve also has slots for displacement tools at both ends.

[0041] See Figure 1 The valve body's sealing cylinder has a through-hole fluid inlet on its side wall; correspondingly, the lower section of the inner sleeve's side wall has a flow groove that communicates with the fluid inlet. Sealing components are installed between the outer wall of the inner sleeve, located above and below the flow groove, and the inner wall of the sealing cylinder, forming a sealing structure at the upper and lower ends of the flow groove. By pressurizing and driving the inner sleeve to move axially downwards and upwards, the overlap area between its flow groove and the fluid inlet can be changed, thus adjusting the flow path and achieving the purpose of controlling downhole hydraulic pressure.

[0042] Preferably, referring to Figure 2, the flow channel in this embodiment consists of several groups of through holes of different sizes. The through holes in each group are distributed circumferentially, while the different groups are arranged axially, and some groups have overlapping portions in the axial direction. The flow channel can adopt any desired shape, size, and arrangement. The solution in this embodiment is not intended to limit the present invention.

[0043] Preferably, the sealing assembly is a Glyd ring, a V-type seal assembly, or an O-ring assembly.

[0044] See Figure 1 and Figure 6 The inner sleeve is fitted with a steering sleeve on its outer side. The inner wall of the steering sleeve is provided with a steering pin and several stepped steps below it. Further, see... Figure 4 It also includes a split stepped cylinder, the upper end of which is connected to the lower end of the steering sleeve via a groove / protrusion structure, allowing the steering sleeve and the stepped cylinder to rotate synchronously. The inner wall of the stepped cylinder has several steps along the circumference.

[0045] See Figure 4 , Figure 5 In this embodiment, several stepped steps are distributed along the circumference, with each horizontal step surface facing upwards axially to contact the lower end face of the stop block; and their dimensions match the stop block. Starting from the highest step surface, the stepped steps sequentially form an axial height difference along the circumference. The height difference can adopt any desired numerical / sequence relationship; this embodiment uses an arithmetic progression relationship, but this should not be construed as a limitation of the invention.

[0046] During the relative circumferential rotation, the stop block contacts each step surface in turn, and the inner sleeve moves down a distance equal to the height difference in turn. As a result, the overlap area between the flow channel and the liquid outlet changes accordingly, and the liquid flow / hydraulic pressure also changes.

[0047] As a preferred option, see Figure 1 The steering sleeve has bearing assemblies at both ends, located between the lower end face of the inner boss in the middle of the outer cylinder and the upper end face of the steering sleeve, and between the lower end face of the steering sleeve and the upper end face of the sealing cylinder, respectively. The bearing assemblies allow for smoother rotation and reduce wear.

[0048] See Figure 1 A control sleeve is provided between the outer wall of the inner sleeve and the inner wall of the steering sleeve. The inner and outer walls of the control sleeve are respectively provided with circumferentially distributed internal and external sliding grooves. Both the internal and external sliding grooves are annular through grooves and are recessed structures. The outer end of the slider on the inner sleeve extends into the internal sliding groove and slides along it, while the inner end of the steering pin of the steering sleeve extends into the external sliding groove and slides along it.

[0049] In this invention, the inner slide groove is wavy, and the outer slide groove is wavy in the opposite direction; and they are concentrically arranged. In use, the inner drive sleeve moves axially up and down, and its slider drives the control sleeve to rotate circumferentially by an angle via the inner slide groove. The outer slide groove of the control sleeve drives the steering sleeve to rotate circumferentially in the opposite direction by another angle via the steering pin. The circumferential rotation angle of the stepped section on the steering sleeve relative to the stop block is the difference between the two angles mentioned above, and then it can contact the corresponding next stepped section, i.e., switch to the next gear.

[0050] The wavy chute features a cyclical characteristic, and the transition structure between the crests and troughs can convert circumferential rotation into cyclic linear movement, and vice versa. By setting a phase difference between two waves to create a reverse driving relationship, the control sleeve and steering sleeve can be driven by the same linear motion to rotate in opposite directions. During this process, the difference in relative rotation angles between the control sleeve and steering sleeve allows for a smaller and more precise circumferential angle adjustment capability. This enables the annular stepped surfaces to be set in a far greater number than in existing technologies, allowing for the sequential switching of more flow rates based on the height differences corresponding to the stepped surfaces.

[0051] As a preferred option, see Figure 3aThe internal slide includes several inner upper end grooves, inner lower end grooves, and inner guide grooves distributed circumferentially. The inner upper end grooves are located on the upper side of the internal slide, while the inner lower end grooves are located on the lower side of the internal slide, and are spaced apart from each other. An inner guide groove is provided circumferentially between the inner upper end grooves and the inner lower end grooves to connect them, guide switching, and drive the control sleeve to perform passive circumferential rotation. When the slider enters a certain inner lower end groove, this embodiment is in a certain gear working state; during the transition state of switching between different gears, the slider will enter the inner upper end groove along the inner guide groove, and then switch to the next adjacent inner lower end groove.

[0052] See Figure 3b The control sleeve's external slide groove includes several axially extending upper outer end grooves, lower inner end grooves, and outer guide grooves distributed circumferentially. The upper outer end grooves are located on the upper side of the external slide groove, while the lower outer end grooves are located on the lower side, and are spaced apart from each other. A circumferentially connected outer guide groove connects the upper inner end groove and the lower inner end groove, guiding the switching and driving the steering sleeve to rotate in the opposite direction. In this embodiment, when in a certain gear position, the steering pin is located in a corresponding upper outer end groove; during the transition between different gear positions, the steering pin moves along the outer guide groove into the lower outer end groove. See also... Figure 3a , Figure 3b In this embodiment, the inner and outer guide grooves are selected from several straight grooves arranged obliquely along the circumference, and the inclination directions of the corresponding inner and outer guide grooves are opposite to each other, forming a reverse wave-like structure. Because straight grooves are used in this embodiment, the wave-like inner and outer grooves both exhibit a sawtooth-like annular groove shape. However, in reality, the inner and outer guide grooves can adopt any shape and trajectory that can satisfy the linear-rotational motion conversion; the solution in this embodiment is not intended to limit the invention.

[0053] As a preferred option, see Figure 3a The inner guide groove, being connected to the inner upper and lower end grooves, forms an inner short inclined side and an inner long inclined side on its two sides. Preferably, the inner short inclined side and the inner long inclined side are parallel, but they can also be arranged at a small angle. See also... Figure 3b The outer guide groove is connected to the outer upper end groove and the outer lower end groove, forming an outer short inclined side and an outer long inclined side on both sides. The outer short inclined side and the outer long inclined side are preferably parallel, but they can also be selected to have a small angle.

[0054] Preferably, the ends of the outer upper end groove, inner lower end groove, and outer upper end groove or outer lower end groove are all provided with transition fillets. Furthermore, the connection between the inner guide groove and the inner upper end groove and the inner lower end groove, as well as the connection between the outer guide groove and the outer upper end groove and the outer lower end groove, are provided with transition fillets. The fillet structure is adapted to the shape of the slider and the end of the steering pin, which is conducive to the smoothness of their sliding.

[0055] In this invention, the outer upper end groove and the inner lower end groove should have different numbers (not equal) so that the central angle between the center lines of adjacent outer upper end grooves (let's call it angle B for ease of description below) and the central angle between the center lines of adjacent inner lower end grooves (let's call it angle A) have an angle difference (let's call it angle C; it's easy to see that angle C = angle A - angle B).

[0056] Specifically, in this embodiment, there are six inner lower end slots (angle A = 60°) and eight outer upper end slots (angle B = 45°), so the difference angle C = 15° (both are evenly distributed along the circumference). During each gear shift cycle, the step rotates 15° circumferentially relative to the stop block. During a complete rotation of the steering sleeve / step cylinder, there can be 360° ÷ 15° = 24 gear positions on the step. The number of outer upper end slots and inner lower end slots, as well as the values ​​of each angle, can be arbitrarily selected within a reasonable range; and the number of inner lower end slots can also be set to be greater than the number of outer upper end slots (i.e., angle A < angle B), by adjusting the circumferential setting direction of the step drop accordingly. Therefore, the solution in this embodiment is not intended to limit the invention.

[0057] See Figure 3b , Figure 4 and Figure 5 The upper outer slots also include a long upper slot corresponding to the fully closed state. The length of the long upper slot extending upwards axially is greater than that of the other short slots (in this embodiment, the short slots are of equal length and selected to meet the requirements). A lower long slot corresponding to the fully closed state (corresponding to position 0) is provided on the stepped platform. See [link to details]. Figure 4 In this embodiment, the lower long groove is an axial through groove. Initially, the steering pin is located at the upper end of the upper long groove, and the stop block is located at the lower end of the lower long groove. At this time, the inner sleeve is located slightly below the valve body, and its lower end is in contact with the inner convex step of the lower cylinder. There is no conductive part between the flow groove and the liquid outlet. In use, the inner sleeve is driven upward, the steering pin enters the outer guide groove along the upper long groove, and at the same time, the stop block moves upward along the lower long groove, eventually passing its upper opening and completely disengaging from it. As the steering pin enters the outer guide groove and the stop block is no longer limited by the lower long groove, with the shifting of gears, the slider sequentially enters the next adjacent lower inner groove, the steering pin enters the subsequent short groove, and the stop block sequentially contacts each stepped step.

[0058] See Figure 5When assembled, the inner sleeve is at the bottom of the valve body, the slider is at the upper end of the upper long groove, the stop is at the lower end of the lower long groove, and the slider is in the inner lower end groove; at this time, this embodiment is in the closed state. In use, this embodiment is installed at the designed position on the intelligent completion string. First, pressure is input from the lower pressure transmission hole to drive the inner sleeve upward. The slider of the inner sleeve slides in the internal groove of the control sleeve, moving upward from the lower end of the inner lower end groove where it was initially located into the inner guide groove, and then along the inner guide groove into the upper end of the next adjacent inner upper end groove; during this process, the slider contacts the inner long inclined side of the upper side of the inner guide groove, causing the control sleeve to rotate circumferentially. The outer groove on the control sleeve, through the steering pin that contacts its upper long groove, causes the steering sleeve and the stepped cylinder to rotate circumferentially in the same direction. The angle of rotation is the central angle (denoted as angle A1) between the centerline of the inner lower end groove of the inner groove and the centerline of the next adjacent inner upper end groove.

[0059] Continued pressure drives the inner sleeve to move upwards. The slider, by contacting the upper end of the inner upper groove, drives the control sleeve to move upwards further. The steering pin slides downwards along the upper long groove into the outer guide groove, and then, through contact with the lower outer long inclined side of the outer guide groove, drives the steering sleeve and the stepped cylinder to rotate synchronously in opposite directions. This angle is the central angle (denoted as angle B1) between the center line of the outer upper groove and the center line of the next adjacent outer lower groove. At this time, the angle C1 of the inner sleeve relative to the stepped cylinder is equal to angle A1 - angle B1. See also Figure 7 At this time, the inner sleeve is in the transition position between the two positions. As the inner sleeve moves upward (its upper end is still in contact with the inner boss of the upper cylinder), the stop block slides out from the lower long groove of the 0 position corresponding to the fully closed state and completely disengages from it.

[0060] Next, the pressure in the lower pressure transmission hole is released, and then pressure is input from the upper pressure transmission hole to drive the inner sleeve downward. The inner sleeve's slider slides axially downward from the upper end of its inner upper groove into the next inner guide groove. Through contact with its lower inner long inclined side, it drives the control sleeve to rotate circumferentially, finally entering the lower end of the next inner lower groove. Simultaneously, the steering pin, through contact with the vertical side of the outer lower groove, drives the steering sleeve and stepped cylinder to rotate circumferentially in the same direction. The angle of rotation for both is the central angle (denoted as angle A2) between the centerline of the inner upper groove and the centerline of the adjacent next inner lower groove.

[0061] The pressure continues to drive the inner sleeve downwards, causing the slider located at the lower end of the inner lower groove to move the control sleeve downwards. At this time, the steering pin enters the outer guide groove of the outer slide and slides. Through contact with the outer long inclined side of the upper side of the outer guide groove, it drives the steering sleeve and the stepped cylinder to rotate in the opposite circumferential direction; this angle is the central angle (denoted as angle B2) between the center line of the outer lower groove and the center line of the next adjacent outer upper groove. At this time, the inner sleeve rotates again relative to the stepped cylinder by an angle C2 = angle A2 - angle B2.

[0062] See Figure 8 After the above rotation is completed, the inner sleeve is in the first working position, and the stop block of the inner sleeve contacts the first step surface of the stepped platform. Correspondingly, the flow groove on the inner sleeve and the liquid outlet of the sealing cylinder have overlapping areas, thus forming a connection and completing the opening. Since the inner sleeve travels the shortest distance downward after opening in the first position, its connection area is also the smallest, thus generating the minimum flow / hydraulic pressure.

[0063] Similarly, the same operation method can be used to shift gears, from gear 1 to gear 2, gear 2 to gear 3, and so on, up to the maximum flow rate gear 23. The desired flow rate gear can be selected according to requirements. After use, the operation can be repeated in a circular motion until returning to the initial gear 0 to shut it off. The above gear shifting can only be done in the order of gear 1 to gear 2 to gear 3 until the desired gear is reached; reverse or skipping gears is not allowed.

[0064] During the entire process of shifting from gear 0 to gear 1, the inner sleeve and the step rotate circumferentially twice, with the resulting relative circumferential rotation angles being:

[0065] Angle C1 = Angle A1 - Angle B1, Angle C2 = Angle A2 - Angle B2;

[0066] Furthermore, based on the structure of the inner and outer sliding grooves, it can be known that:

[0067] Angle A = Angle A1 + Angle A2, Angle B = Angle B1 + Angle B2;

[0068] Therefore, we get: Angle C = Angle (C1 + C2)

[0069] = Angle (A1+A2) - Angle (B1+B2)

[0070] = Angle A - Angle B.

[0071] Therefore, during each complete gear shift cycle, the angle at which the step rotates circumferentially relative to the inner sleeve is the difference between the central angle between the centerlines of two adjacent inner lower end grooves and the central angle between the centerlines of two adjacent outer upper end grooves. The sign of this value indicates the direction of circumferential rotation.

[0072] Furthermore, given that angles A and B are determined, whether angles A1 and A2, and angles B1 and B2 are the same or different, the effect of relative rotation angle C between the inner sleeve and the steering sleeve can be achieved. The selection of values ​​does not constitute a limitation on the present invention.

[0073] This embodiment achieves the reverse rotation of the inner sleeve and the stepped cylinder by setting the internal and external sliding grooves of the control sleeve in a reverse wave shape, forming differential angle control. This allows the present invention to set more fluid flow levels in the valve body of the same diameter, easily achieving more than 20 levels of level selection. It overcomes the insufficiency of the number of producing layers controlled by existing flow control valves and meets the higher requirements for multi-producing wells.

[0074] Since the relative rotation angle for shifting gears comes from the difference in rotation angles between the two components, only a relatively small number of upper outer grooves and lower inner grooves need to be set on the inner and outer walls of the control sleeve, and the corresponding angle difference can be set as needed. This avoids the predicament of existing technologies that require more than 20 shifting grooves to be opened along the circumference of the tool's outer wall to achieve the technical objective. Therefore, the transmission structure is simple, has high pressure resistance, reliable sealing, and is easy to manufacture and process, resulting in lower costs.

[0075] The embodiments of the present invention have been described above with reference to the accompanying drawings and examples. The structures given in the embodiments do not constitute a limitation of the present invention. Those skilled in the art can make adjustments as needed, and various modifications or variations within the scope of the appended claims are all within the scope of protection.

Claims

1. A differential multi-stage hydraulic control valve, comprising a valve body, characterized in that: The valve body has an axially movable inner sleeve inside, and a slider and a stop are provided on the outer wall of the middle section of the inner sleeve. The inner sleeve is fitted with a steering sleeve on the outside. The inner wall of the steering sleeve is provided with a steering pin and several stepped steps arranged along the circumference to form an axial drop. A control sleeve is provided between the inner sleeve outer wall and the steering sleeve inner wall. The inner wall and outer wall of the control sleeve are respectively provided with an inner groove and an outer groove. The inner groove is wavy and the outer groove is wavy in the opposite direction. During use, the inner drive sleeve moves up and down along the axis, and the slider drives the control sleeve to rotate circumferentially by an angle through the internal slide groove. The outer slide groove of the control sleeve drives the steering sleeve to rotate circumferentially in the opposite direction by another angle through the steering pin. The circumferential rotation angle of the step relative to the stop is the difference between the two angles mentioned above, and then switches to the next step.

2. The differential multi-stage hydraulic control valve according to claim 1, characterized in that: The internal slide groove of the control sleeve includes several inner upper end grooves and inner lower end grooves distributed at intervals along the circumference, and an inner guide groove that connects the inner upper end grooves and inner lower end grooves and is used to guide switching and drive the control sleeve to rotate circumferentially. And / or, the outer groove of the control sleeve includes a plurality of outer upper end grooves and inner lower end grooves that are distributed circumferentially and extend upward along the axial direction, and an outer guide groove that connects the outer upper end grooves and the outer lower end grooves and is used to guide the switching and drive the steering sleeve to rotate in the opposite direction in the circumferential direction. And / or, the inner and outer guide grooves are several straight grooves arranged obliquely along the circumference, and the inclination directions of the corresponding inner and outer guide grooves are opposite to each other.

3. The differential multi-stage hydraulic control valve according to claim 2, characterized in that: There is an angular difference between the central angle between adjacent upper outer grooves and the central angle between adjacent lower inner grooves; And / or, the outer upper end groove and the inner lower end groove have different numbers, and are evenly distributed along the circumference respectively; And / or, the number of inner lower end slots is six and the number of outer upper end slots is eight; each time a gear is changed, the step rotates 15° relative to the stop block in the circumferential direction, and one rotation of the step corresponds to 24 gears.

4. The differential multi-stage hydraulic control valve according to claim 2, characterized in that: Among the several outer upper end slots, there is an upper long slot corresponding to the fully closed state, and the length of the upper long slot extending upward along the axial direction is greater than that of the other short slots; several stepped steps are provided with lower long slots corresponding to the fully closed state. Initially, the steering pin is located at the upper end of the upper long groove and the stop is located at the lower end of the lower long groove. During use, the inner sleeve moves upward, the steering pin enters the outer guide groove along the upper long groove, and at the same time the stop moves upward along the lower long groove and disengages from it. As the gear shift is completed, the steering pin enters the short groove and the stop contacts the next step.

5. The differential multi-stage hydraulic control valve according to claim 2, characterized in that: The ends of the upper outer end groove, the lower inner end groove, the upper outer end groove, or the lower outer end groove are set with transition fillets; And / or, the connection between the inner guide groove and the inner upper end groove and the inner lower end groove is provided with a transition fillet; And / or, the connection between the outer guide groove and the outer upper end groove and the outer lower end groove is provided with a transition fillet.

6. The differential multistage hydraulic control valve according to any one of claims 1-5, characterized in that: The steering sleeve has bearing assemblies at both ends.

7. The differential multistage hydraulic control valve according to any one of claims 1-5, characterized in that: It also includes a stepped cylinder, the upper end of which is connected to the lower end of the turning sleeve, and the inner wall of the stepped cylinder is provided with several steps along the circumferential direction. And / or, the upper end of the stepped cylinder is connected to the lower end of the steering sleeve by a groove / protrusion structure.

8. The differential multi-stage hydraulic control valve according to claim 1, characterized in that: A sealing assembly is provided between the outer wall of the upper section of the inner sleeve and the inner wall of the valve body. The upper and lower parts of the sealing assembly are respectively connected to the upper pressure transmission hole and the lower pressure transmission hole. The pressure of the upper pressure transmission hole and the lower pressure transmission hole pushes the inner sleeve to move downward and upward respectively. And / or, there is an angular difference between the slider and the stop in the circumferential direction. And / or, the two ends of the inner sleeve are respectively provided with slots for displacement tools.

9. The differential multi-stage hydraulic control valve according to claim 1, characterized in that: The lower section of the valve body has a through-flow port on its side wall, and the lower section of the inner sleeve has a flow groove that can communicate with the flow port on its side wall. Sealing components are provided between the outer wall of the inner sleeve located above and below the flow groove and the inner wall of the valve body.

10. The differential multi-stage hydraulic control valve according to claim 8 or 9, characterized in that: The sealing assembly is a Glyd ring, a V-type seal assembly, or an O-ring assembly.

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