Multi-mode layered water injection system

Abstract

The invention relates to the technical field of oil field layered mining, in particular to a multi-mode layered water injection system which comprises a water distribution packer and a double-layer injection and production measurement and control valve, the double-layer injection and production measurement and control valve is detachably arranged in the water distribution packer, and the double-layer injection and production measurement and control valve can be fished to the ground; when the double-layer injection and production measurement and control valve is located on the ground, the cloud server presets different preset water injection schemes into the double-layer injection and production measurement and control valve through the wireless transmission module, and each preset water injection scheme comprises a corresponding water injection mode and water injection parameters corresponding to the mode; an internal ceramic combination valve is controlled to be opened or closed for layered water injection; wherein the water injection mode at least comprises balanced flow water injection, pulsating flow water injection, stable pressure water injection and periodic pressure water injection. Multi-parameter coupling regulation and control of flow, pressure and temperature can be achieved, dynamic switching of multiple water injection modes is supported, and cable-free intelligent control over underground equipment is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of oilfield layered production, and particularly to a multi-modal layered water injection system. Background Art

[0002] In the field of oilfield layered water injection development, maintaining reservoir pressure balance is a key technical link to ensure oil recovery rate. The current commonly used layered water injection process in the industry has the following technical problems: 1. Control accuracy defect: The traditional method of adjusting the flow rate of each layer by manually replacing the water nozzle is difficult to achieve precise adjustment of the water injection layer section (error rate > 15%), resulting in intensified interlayer contradictions; especially when the permeability difference of the reservoir is too large, the existing technology cannot effectively control the water injection intensity of the layer section. 2. Dynamic response lag: Based on the existing test data, when adjusting the water injection pressure of the layer section, the instrument needs to be taken out, the water nozzle needs to be replaced, and then it is lowered into the well. The time for the formation to absorb water and reach rebalance is fast for dozens of minutes and slow for several days. It cannot be adjusted in real time according to the formation pressure, resulting in water injection imbalance. The water injection imbalance rate of the traditional process can reach more than 50%. 3. Single regulation mode: The layered water injection scheme specified in the industry standard SY / T5565-2018 only supports the constant flow mode and lacks support for other water injection modes, resulting in a water injection efficiency of less than 35% for low-permeability reservoirs. 4. Low cost performance: The existing cable-type measurement and control system has the following problems: the cost is too high. For each operation of the water well, a set of downhole cables and cable protection devices will be consumed; the operation construction time is extended by more than 3 times, the operation cost is increased, and the work efficiency is reduced; the construction success rate is low. During the operation construction process, the cable is often damaged and needs to be re-constructed. The one-time success rate of the operation construction of lowering the cable into the well is less than 70%. Summary of the Invention

[0003] The present invention provides a multi-modal layered water injection system to solve the problems that it is difficult to achieve precise adjustment of the water injection layer section in the existing layered water injection process; there is a delay in adjusting the water injection pressure by tripping the tubing string, resulting in water injection imbalance; lack of support for other water injection modes, resulting in insufficient water injection efficiency of the reservoir; and the construction cost of the cable measurement and control system is high and the construction success rate is low.

[0004] According to one aspect of the present invention, there is provided a multi-modal layered water injection system, comprising:

[0005] Lower the water distribution packer to a predetermined position in the well. Each of the water distribution packers corresponds to two layers. A double-layer injection-production measurement and control valve is removably seated inside each of the water distribution packers, and the double-layer injection-production measurement and control valve can be fished to the ground;

[0006] When the double-layer injection-production measurement and control valve is on the ground, the cloud server pre-installs different preset water injection schemes into the double-layer injection-production measurement and control valve through a wireless transmission module. Each preset water injection scheme includes a corresponding water injection mode and water injection parameters corresponding to this mode. According to the preset water injection scheme, it controls the opening or closing of the internal ceramic combination valve to carry out layered water injection; among them, the water injection mode at least includes: balanced flow water injection, pulsating flow water injection, stable pressure water injection, and periodic pressure water injection;

[0007] Among them, for the balanced flow water injection and pulsating flow water injection, the injection volume of the controlled layer is the predetermined injection volume, and for the stable pressure water injection and periodic pressure water injection, the injection pressure of the controlled layer is the predetermined injection pressure; among them, the balanced flow water injection and stable pressure water injection are continuous and uninterrupted water injection modes, and the pulsating flow water injection and periodic pressure water injection are fluctuating intermittent water injection modes.

[0008] Preferably, the balanced flow water injection is as follows: determining the full-well injection pressure according to the layer with the worst water absorption and the full-well water absorption indication curve, and using this full-well injection pressure to inject water into each layer; the double-layer injection-production measurement and control valve collects the real-time formation pressure, and determines the shutdown time ratio of each layer according to it, and injects water according to this shutdown time ratio to make the injection volume within the layer period reach the predetermined injection volume; after each cycle of water injection is completed, readjust the shutdown time ratio and the full-well injection pressure according to the actual injection volume of the layer to make the actual injection volume within the layer period reach the predetermined injection volume;

[0009] The pulsating flow water injection is as follows: polling and injecting water into each layer in turn at the predetermined maximum injection pressure. If the predetermined injection volume cannot be completed within one water injection cycle, several layers with similar water absorption characteristics are combined for water injection;

[0010] The stable pressure water injection is as follows: injecting water into each layer at the predetermined minimum injection pressure. The double-layer injection-production measurement and control valve collects the real-time formation pressure and judges whether the real-time formation pressure is not equal to the predetermined formation pressure. If so, water injection adjustment is carried out by controlling the opening or closing of the ceramic combination valve to make the real-time formation pressure equal to the predetermined formation pressure;

[0011] The periodic pressure water injection is as follows: determining the minimum full-well injection pressure according to the highest formation pressure of each layer, and injecting water into the layer according to this minimum full-well injection pressure; the double-layer injection-production measurement and control valve controls periodic water injection operations according to the predetermined water injection pressure period of its corresponding layer. During each cycle of water injection, when the real-time formation pressure reaches the predetermined maximum pressure corresponding to this layer, stop injecting after maintaining the injection for a predetermined time. When the real-time formation pressure drops to the predetermined pressure, control the next cycle of water injection;

[0012] To switch to the water injection mode, the double-layer injection-production measurement and control valve receives the pressure pulse coding instruction transmitted from the ground and conducts water injection according to the water injection plan corresponding to the instruction.

[0013] Preferably, the double-layer injection-production measurement and control valve includes: a sensor stub string, an isolation drive sleeve, and a lower sealing tail cone that are connected in sequence;

[0014] A pressure detection unit for detecting the real-time formation pressure and water injection pressure, a temperature sampling circuit for detecting the real-time formation temperature, and a control circuit connected to the pressure detection unit and the temperature detection unit are provided inside the sensor stub string;

[0015] A reduction motor, an isolation coupling, a measurement and control valve reducer, and a limit coupling rod that are connected in sequence are provided inside the isolation drive sleeve. The limit coupling rod is connected to the ceramic combination valve, and the reduction motor is connected to the control circuit;

[0016] The ceramic combination valve is provided inside the lower sealing tail cone.

[0017] Preferably, the ceramic combination valve includes: a valve core and a valve sleeve;

[0018] The valve core is inside the valve sleeve;

[0019] Two symmetrically arranged upper holes on the valve core and two upper holes on the valve sleeve corresponding to the upper holes on the valve core are provided;

[0020] A first lower hole on the valve core and a second lower hole on the valve core are provided on the valve core. The first lower hole on the valve core corresponds to the position of any one of the upper holes on the valve core, and the position of the second lower hole on the valve core corresponds to the midpoint position between the two upper holes on the valve core;

[0021] A lower hole on the valve sleeve corresponding to the second lower hole on the valve core is provided on the valve sleeve;

[0022] Bottom holes are provided at one ends of the valve core and the valve sleeve away from the limit coupling rod;

[0023] The upper holes on the valve core and the upper holes on the valve sleeve form an upper channel, and the first lower hole on the valve core, the second lower hole on the valve core, and the lower hole on the valve sleeve form a lower channel.

[0024] Preferably, the water distribution packer includes: a packer body;

[0025] An upper layer water outlet channel is provided on the side wall of the packer body. The upper layer water outlet channel is respectively communicated with the upper layer formation and the upper channel. A lower layer water injection channel is provided inside the side wall of the packer body. The lower layer water injection channel is respectively communicated with the lower layer formation and the lower channel;

[0026] A lower layer pressure transmission channel is provided inside the side wall of the packer body, one end of the lower layer pressure transmission channel is connected to the pressure detection unit, and the other end is connected to the lower layer water injection channel;

[0027] A bridge-type flow channel is provided inside the side wall of the packer body. One end of the bridge-type flow channel is connected to the oil tubing string above the packer body, and the other end is connected to the oil tubing string below the packer body.

[0028] Preferably, the method of detachably installing a double-layer injection, production, measurement and control valve inside each water distribution packer comprises:

[0029] The double-layer injection and production control valve is provided with a card slot, and the interior of the packer body is provided with a seat card point that cooperates with the card slot;

[0030] A plurality of packer bodies are provided in the wellbore, and the diameter of the seat point inside each packer body is smaller than the diameter of the seat point inside the packer body above it;

[0031] A conventional packer is arranged between two adjacent packer bodies;

[0032] The double-layer injection and production control valve is sequentially placed from the wellhead into the packer body according to the diameter of the slot from small to large, and the installation is completed by matching the corresponding seat points and the slot.

[0033] Preferably, the method of controlling the opening or closing of the internal ceramic combination valve to perform stratified water injection according to a preset water injection scheme includes:

[0034] When performing stratified water injection, the reduction motor is controlled to start, and the valve core is driven to rotate at different angles through the isolation coupling, the measurement and control valve reducer, and the limit coupling rod, so that the upper hole of the valve core and the upper hole of the valve sleeve, and the lower hole of the second valve core and the lower hole of the valve sleeve are overlapped, or the upper hole of the valve core and the upper hole of the valve sleeve are staggered, and the lower hole of the first valve core and the lower hole of the valve sleeve are overlapped, or the upper hole of the valve core and the upper hole of the valve sleeve are overlapped, and the lower holes of the first and second valve cores and the lower hole of the valve sleeve are staggered, or the upper hole of the valve core and the upper hole of the valve sleeve, and the lower hole of the first valve core and the lower hole of the valve sleeve are staggered;

[0035] The injected water enters the valve core from the tubing string above the packer body through the bridge flow channel, the bottom opening of the lower sealing tail cone, the valve sleeve and the bottom hole of the valve core in sequence, and enters the upper formation of the two layers through the upper channel and the upper water outlet channel, and / or, the injected water enters the lower formation of the two layers from the inside of the valve core through the lower channel and the lower water injection channel.

[0036] Preferably, a communication unit is provided inside the double-layer injection-production measurement and control valve, and the communication unit is connected to the pressure detection unit and the temperature sampling circuit;

[0037] The communication unit is used to transmit, via a wireless transmission module, the data detected by the pressure detection unit and the temperature sampling circuit, as well as the data on the open or closed state of the upper channel and / or the lower channel of the ceramic combination valve controlled by the control circuit according to the water injection scheme, to the cloud server.

[0038] Preferably, a passive cloud-controlled high-pressure valve is provided on the water injection pipeline at the wellhead, and the injection flow rate and pressure are adjusted by controlling the opening or closing of the passive cloud-controlled high-pressure valve;

[0039] Among them, the passive cloud-controlled high-pressure valve includes: a high-pressure valve body, a DC motor, a solar power supply mechanism, and a remote control module;

[0040] The DC motor is connected to a first-stage reducer, the first-stage reducer is connected to a second-stage reducer, and the second-stage reducer is connected to the high-pressure valve body through a coupling;

[0041] The solar power supply mechanism is respectively connected to the DC motor and the remote control module;

[0042] The DC motor is connected to the remote control module, and the remote control module is used to control the start of the DC motor according to the received control instruction, and drive the high-pressure valve body to rotate through the first-stage reducer and the second-stage reducer;

[0043] and / or,

[0044] The solar power supply mechanism includes: a cylindrical solar outer cover composed of a plurality of solar panels and a battery connected to the solar panels; the DC motor, the first-stage reducer, the second-stage reducer, the remote control module, and the coupling are installed inside the solar outer cover;

[0045] Preferably, the output torque of the DC motor is determined, and the driving torque after being reduced by the first-stage reducer and the second-stage reducer is determined according to the output torque;

[0046] The opening torque of the ball valve of the high-pressure valve body is determined, and the parameters of the DC motor, the first-stage reducer, and the second-stage reducer are determined according to the ball valve opening torque and the driving torque.

[0047] The present invention has at least the following beneficial effects:

[0048] The present invention provides a multi-modal stratified water injection system. By designing a retrievable double-layer injection-production measurement and control valve and loading different preset water injection schemes in it through a cloud server, it realizes water injection in different water injection modes, and further realizes multi-parameter coupling regulation of flow rate, pressure, and temperature. Multiple water injection modes can be dynamically switched, achieving the purpose of cable-free intelligent control of downhole equipment. Brief Description of the Drawings

[0049] The accompanying drawings here are incorporated into the specification and form a part of this specification. These drawings show embodiments consistent with the present invention and, together with the specification, are used to illustrate the technical solutions of the present invention.

[0050] Figure 1 The structural schematic diagram of a multi-modal stratified water injection system according to an embodiment of the present invention is shown.

[0051] Figure 2 It is the structural schematic diagram of a double-layer injection-production measurement and control valve in an embodiment of the present invention;

[0052] Figure 3 It is the structural schematic diagram of a packer body in an embodiment of the present invention;

[0053] Figure 4 It is the structural schematic diagram of a valve core in an embodiment of the present invention;

[0054] Figure 5 It is the structural schematic diagram of a valve sleeve in an embodiment of the present invention;

[0055] Figure 6 It is the structural schematic diagram of a passive cloud-controlled high-pressure valve for an injection well in an embodiment of the present invention.

[0056] In the figure, 1 - battery cylinder, 2 - communication short circuit, 3 - sensor short circuit, 4 - isolation drive sleeve, 5 - union swivel, 6 - union inner ring, 7 - union outer ring, 8 - second limit ring, 9 - first limit ring, 10 - limit coupling rod, 11 - lower sealing tail cone, 12 - first upper sealing ring, 13 - rope cap, 14 - battery pack, 15 - control circuit, 16 - reduction motor, 17 - isolation coupling, 18 - measurement and control valve reducer, 19 - ceramic combination valve, 20 - first upper sealing surface, 21 - second upper sealing surface, 22 - first lower sealing surface, 23 - second lower sealing surface, 24 - seating card point, 25 - bridge flow channel, 26 - lower pressure transmission channel, 27 - lower water injection channel, 28 - upper water outlet channel, 29 - lower water outlet channel, 30 - packer sealing rubber sleeve, 31 - upper joint, 32 - lower joint, 33 - second upper sealing ring, 34 - first lower sealing ring, 35 - second lower sealing ring, 40 - valve core, 41 - valve sleeve, 42 - sealing groove, 43 - rotating slot, 44 - fixing groove, 45 - upper hole of valve core, 46 - lower hole of valve core, 47 - upper hole of valve sleeve, 48 - lower hole of valve sleeve, 49 - high-pressure valve body, 50 - coupling, 51 - coupling support, 52 - secondary reducer, 53 - primary reducer, 54 - DC motor, 55 - solar outer cover, 56 - circuit board, 57 - waterproof top cover, 58 - positioning Hall sensor, 59 - counting Hall sensor, 60 - right connection clamp, 61 - right connection body, 62 - second pressure gauge, 63 - second pressure gauge connection channel, 64 - left connection clamp, 65 - left connection body, 66 - first pressure gauge, 67 - first pressure gauge connection channel, 68 - battery cavity, 69 - passive cloud control high-pressure valve, 70 - integrated linear flowmeter, 71 - primary water distribution packer, 72 - secondary water distribution packer, 73 - tertiary water distribution packer, 74 - conventional packer. Detailed implementation manners

[0057] Various exemplary embodiments, features and aspects of the present invention will be described in detail below with reference to the accompanying drawings. The same reference numerals in the drawings denote elements having the same or similar functions. Although various aspects of the embodiments are shown in the drawings, the drawings do not have to be drawn to scale unless otherwise specified.

[0058] The special term "exemplary" here means "serving as an example, an embodiment or an illustration". Any embodiment described as "exemplary" here does not have to be construed as superior to or better than other embodiments.

[0059] As used herein, the term "and / or" is merely a description of the relationship between associated objects, indicating that there can be three relationships. For example, A and / or B can represent three cases: A exists alone, A and B exist simultaneously, and B exists alone. Additionally, the term "at least one" as used herein means any one of a plurality or any combination of at least two of a plurality. For example, including at least one of A, B, and C can mean including any one or more elements selected from the set consisting of A, B, and C.

[0060] In addition, for a better illustration of the present invention, numerous specific details are given in the following detailed embodiments. Those skilled in the art should understand that the present invention can still be implemented without some of these specific details. In some instances, methods, means, elements, and circuits well-known to those skilled in the art are not described in detail to highlight the gist of the present invention.

[0061] Figure 1 Shows a schematic structural diagram of a multimodal stratified water injection system according to an embodiment of the present invention. Figure 2 Is a schematic structural diagram of a double-layer injection-production measurement and control valve in an embodiment of the present invention; Figure 3 Is a schematic structural diagram of a packer body in an embodiment of the present invention; Figure 4 Is a schematic structural diagram of a valve core in an embodiment of the present invention; Figure 5 Is a schematic structural diagram of a valve sleeve in an embodiment of the present invention; Figure 6 Is a schematic structural diagram of a passive cloud-controlled high-pressure valve for an injection well in an embodiment of the present invention. As Figures 1-6 Shown, a multimodal stratified water injection system includes: lowering a water distribution packer to a predetermined position underground, each of the water distribution packers corresponding to two intervals, and a double-layer injection-production measurement and control valve being detachably seated inside each of the water distribution packers, the double-layer injection-production measurement and control valve being retrievable to the ground; when the double-layer injection-production measurement and control valve is on the ground, a cloud server preloads different preset water injection schemes into the double-layer injection-production measurement and control valve through a wireless transmission module, each preset water injection scheme including a corresponding water injection mode and water injection parameters corresponding to the mode, and controlling the opening or closing of an internal ceramic combination valve thereof for stratified water injection according to the preset water injection scheme; wherein, the water injection mode at least includes: balanced flow water injection, pulsating flow water injection, stable pressure water injection, and periodic pressure water injection; wherein, the balanced flow water injection and pulsating flow water injection are to control the injection volume of the interval to a predetermined injection volume, and the stable pressure water injection and periodic pressure water injection are to control the injection pressure of the interval to a predetermined injection pressure; wherein, the balanced flow water injection and stable pressure water injection are continuous and uninterrupted water injection modes, and the pulsating flow water injection and periodic pressure water injection are fluctuating intermittent water injection modes.

[0062] In the embodiment of the present invention, the water distribution packer includes: a packer body. During use, the double-layer injection-production measurement and control valve is seated inside the packer body; both ends of the packer body are respectively connected to the production tubing string through an upper joint 31 and a lower joint 32, that is, the upper joint 31 is connected to the upper tubing string, and the lower joint 32 is connected to the lower tubing string. The packer body is lowered into a predetermined position in the well together with the production tubing string. Or, the packer body is connected to the production tubing string and lowered into a predetermined position in the well, and then the top of the double-layer injection-production measurement and control valve is connected to a cable through a rope cap 13, and the double-layer injection-production measurement and control valve is lowered into the inside of the packer body in the well by using the cable.

[0063] Each water distribution packer body and the double-layer injection-production measurement and control valve inside correspond to two formations. During the water injection operation, the double-layer injection-production measurement and control valve controls the opening or closing of the ceramic combination valve according to the default preset water injection scheme inside for layered water injection. During the water injection process, the double-layer injection-production measurement and control valve collects the real-time pressure and temperature data of the underground formation, controls and drives the movement of the ceramic combination valve 19 for on-off control according to it, and injects water according to the water injection mode and water injection parameters corresponding to the preset water injection scheme, where the water injection parameters include injection volume, injection pressure, injection time, etc.

[0064] The double-layer injection-production measurement and control valve adopts a retrievable design. When lowering, it relies on gravity to be seated into the corresponding water distribution packer. When fishing, it can be lifted to the ground through a wire rope. The double-layer injection-production measurement and control valve is connected to a cloud server through a wireless network. A set or multiple sets of water injection schemes are stored inside the cloud server to form a water injection scheme group. When the double-layer injection-production measurement and control valve reaches the well site or is fished to the ground, the double-layer injection-production measurement and control valve will automatically download the water injection scheme group composed of multiple sets of water injection schemes from the cloud server through the wireless network (wireless transmission module) and copy it completely into each double-layer injection-production measurement and control valve.

[0065] When the double-layer injection-production measurement and control valve controls water injection, there is no need to adjust the valve opening, only full-open or full-close actions are required.

[0066] In the present invention, the balanced flow water injection is as follows: determining the full-well injection pressure according to the worst water-absorbing interval and the full-well water absorption indication curve, and using this full-well injection pressure to inject water into each interval; the double-layer injection-production measurement and control valve collects the real-time pressure of the formation and determines the shutdown time ratio of each interval according to it, and injects water according to this shutdown time ratio so that the injection volume within the interval period reaches the predetermined injection volume; after each cycle of water injection is completed, readjust the shutdown time ratio and the full-well injection pressure according to the actual injection volume of the interval so that the actual injection volume within the interval period reaches the predetermined injection volume;

[0067] The pulsating flow water injection is as follows: polling and injecting water into each interval in turn at the predetermined maximum injection pressure. If the predetermined injection volume cannot be completed within one water injection cycle, several intervals with similar water absorption characteristics are combined for water injection;

[0068] The stable pressure water injection is as follows: water is injected into each layer according to a predetermined minimum injection pressure. The double-layer injection and production measurement and control valve collects the real-time formation pressure and determines whether the real-time formation pressure is not equal to the predetermined formation pressure. If so, the water injection is adjusted by controlling the opening or closing of the ceramic combination valve to make the real-time formation pressure equal to the predetermined formation pressure.

[0069] The cyclic pressure water injection comprises: determining the minimum full-well injection pressure according to the maximum formation pressure of each layer, and injecting water into the layer according to the minimum full-well injection pressure; the double-layer injection and production measurement and control valve controls the cyclic water injection operation according to the predetermined water injection pressure cycle of the corresponding layer. During each cyclic water injection process, when the real-time formation pressure reaches the predetermined maximum pressure corresponding to the layer, the injection is stopped after the predetermined time. When the real-time formation pressure drops to the predetermined pressure, the next cyclic water injection is controlled.

[0070] If the water injection mode is to be switched, the double-layer injection and production measurement and control valve receives the pressure pulse coding instruction transmitted from the ground and injects water according to the water injection plan corresponding to the instruction.

[0071] In an embodiment of the present invention, when the injection mode is balanced flow injection, the injection plan defines the daily injection rate for each layer. Therefore, daily balanced water injection can be performed on a 24-hour cycle. In this mode, a baseline full-well injection pressure is first determined based on the reinforced layer with the worst water absorption and the full-well water absorption indicator curve. Based on this, a preliminary calculation is made for the shut-in / shut-off time ratio for each layer. Within a 24-hour cycle, the dual-layer injection and production control valve controls the ceramic combination valve to shut down multiple times based on the shut-in / shut-off time ratio to control the 24-hour water injection rate for that layer. Due to the influence of the actual construction surface, the actual injection rate may not match the planned injection rate. Therefore, after each 24-hour injection is completed, the shut-in / shut-off time ratio and full-well injection pressure are gradually adjusted based on the actual water injection rate for each layer. After several adjustments, a balanced flow injection state for the entire well can be achieved. Even after water absorption occurs in a layer, the adjustment mechanism continuously adapts to the new situation to achieve the injection target for each layer as much as possible.

[0072] When the water injection mode is the pulsating flow water injection mode, the water injection allocation for each interval and the pulsating flow period are defined in the water injection plan. In this mode, first, within one pulsating flow period, each interval is sequentially water injected with the highest allowed pressure set. After a certain interval has completed the predetermined injection volume, it immediately moves on to the next interval. If within one pulsating flow period (water injection period), all intervals can complete the predetermined injection volume, then continue to perform interval polling water injection in this way. After an interval has completed the water injection according to the predetermined injection volume, during the remaining time within one pulsating flow period, all intervals stop water injection. If not all intervals can complete the injection volume within one pulsating flow period, then two or more intervals with similar water absorption characteristics, especially the enhanced intervals with poor water absorption and the intervals that take a long time, etc., need to be combined for water injection. During the combined water injection time, the flow rates of the combined intervals are distributed and statistically analyzed based on their water absorption indicator curves.

[0073] When the water injection mode is the stable pressure water injection mode, the formation pressures required for each interval are defined in the water injection plan. In this mode, based on the formation pressures required for each interval, the minimum wellhead injection pressure required on the ground can be calculated. The ground system maintains this minimum wellhead injection pressure for water injection, while each interval downhole adjusts its own opening and closing according to its own formation pressure, that is, to reach the predetermined injection pressure. Specifically: The double-layer injection-production measurement and control valve collects the real-time formation pressure of the corresponding interval. If it exceeds the predetermined formation pressure, the ceramic combination valve is closed to stop water injection; if it is lower than the predetermined formation pressure, the ceramic combination valve is opened for water injection.

[0074] When the water injection mode is the periodic pressure water injection mode, the highest formation pressure, the highest pressure maintenance time, and the pressure cycle time for each interval are defined in the water injection plan. In this mode, different pressure cycles can be defined for each interval. Based on the highest formation pressures required for each formation, the minimum wellhead pressure required on the ground can be calculated. The ground system maintains this wellhead pressure for water injection, while each interval downhole is independently controlled and has no relation with the whole well and other intervals. According to the predetermined water injection pressure cycle of the interval itself, the double-layer injection-production measurement and control valve controls the ceramic combination valve to open for water injection, injects the pressure of the corresponding interval to the highest formation pressure required, that is, the predetermined injection pressure, and maintains the corresponding predetermined time, that is, the highest pressure maintenance time, then controls the ceramic combination valve to close and stop water injection, waiting for the end of this pressure cycle, that is, when the real-time formation pressure drops to the predetermined pressure, and then proceeds to the next cycle of water injection, and so on in a cycle.

[0075] The multi-modal stratified water injection system realizes multi-modal water injection control by presetting a water injection plan and the coordinated operation of the surface and downhole parts: the double-layer injection-production measurement and control valve performs layer opening and closing operations according to the preset program, and the surface control unit synchronously implements dynamic adjustment of flow rate or pressure, jointly realizing four basic modes and their combined modes of balanced flow water injection, pulsating flow water injection, stable pressure water injection, and periodic pressure water injection. If balanced flow water injection or stable pressure water injection is to be carried out, all the downhole layers can be opened, and the surface continuously injects the full well flow rate or maintains the full well injection pressure. When encountering a restricted layer with good water absorption, such a layer can complete the injection allocation or reach the target pressure in a short time, and the layer can be intermittently shut off at a higher frequency. For its formation, it is still the effect of continuous limited injection. Whether it is flow control or pressure control, the logic is the same. If pulsating flow water injection or periodic pressure water injection is to be carried out, it can be achieved by layer-by-layer alternate injection. If the full well water injection volume or injection pressure cannot be completed within the alternate injection cycle, multi-layer simultaneous injection is required. When multi-layer simultaneous injection is carried out in the flow control mode, the distribution of the downhole stratified flow rate is based on the water absorption indication curve.

[0076] The water absorption indication curve is the relationship curve between the formation injection pressure and the water absorption capacity. The formation characteristics will not change in a short period of time, and its water absorption indication curve will not mutate. Therefore, according to needs, it is only necessary to test the water absorption indication curves of each layer for a long time. When the water absorption indication curve needs to be tested, single-layer water injection is carried out for each layer in the whole well range in turn. At this time, the surface injection flow rate is the water absorption volume of this layer, and the formation injection pressure of this layer can be calculated from the surface injection pressure during the water injection of this layer. By adjusting different surface injection pressures or injection flow rates, the water absorption indication curve of this layer can be obtained.

[0077] During normal water injection operation, the double-layer injection-production measurement and control valve always records the formation pressure, tubing pressure, and temperature of each layer. When the layer water injection is just closed, it will also collect and record the formation pressure in the most intensive manner according to the preset time schedule to obtain the most precise formation pressure drop curve for well test analysis that may be required. When the double-layer injection-production measurement and control valve is fished to the surface, the collected data is transmitted to the cloud server through wireless network.

[0078] In order to prevent the mutual interference between the surface system and the downhole system from causing adjustment oscillation and imbalance, the same adjustment period and the best adjustment time phase point can be specified for the surface water injection system and the downhole stratified water injection system, that is, when the surface water injection flow rate is adjusted to decrease or increase, the preset formation pressure of the downhole stratified water injection system should be adjusted synchronously. On the one hand, this can prevent the mutual interference between the surface and the downhole from causing oscillation and imbalance, and on the other hand, it can also prevent the valves from being frequently adjusted, increasing the power consumption.

[0079] In the present invention, the double-layer injection-production measurement and control valve includes: a sensor stub 3, an isolation drive sleeve 4, and a lower sealing tail vertebra 11 that are connected in sequence; a pressure detection unit for detecting the real-time formation pressure and injection pressure, a temperature sampling circuit for detecting the real-time formation temperature, and a control circuit 15 connected to the pressure detection unit and the temperature detection unit are provided in the sensor stub 3; a reduction motor 16, an isolation coupling 17, a measurement and control valve reducer 18, and a limit coupling rod 10 are sequentially connected in the isolation drive sleeve 4, the limit coupling rod 10 is connected to the ceramic combination valve 19, and the reduction motor 16 is connected to the control circuit 15; the ceramic combination valve 19 is provided in the lower sealing tail vertebra.

[0080] In an embodiment of the present invention, as Figure 2 shown, the sensor stub of the double-layer injection-production measurement and control valve is connected to a battery cylinder 1, a battery pack 14 is provided in the battery cylinder 1, and the battery pack 14 is connected to and supplies power to the pressure detection unit, the temperature sampling circuit, the control circuit 15, and the reduction motor 16.

[0081] The pressure detection unit includes: a first pressure sensor 66, a second pressure sensor 52, and a third pressure sensor; the first pressure sensor 66 communicates with the upper formation and is used for detecting the real-time pressure of the upper formation; the second pressure sensor 52 communicates with the lower formation and is used for detecting the real-time pressure of the lower formation; the third pressure sensor communicates with the inside of the water distribution packer and is used for detecting the real-time injection pressure. At the same time, the pressure sensors transmit the detected data to the control circuit 15.

[0082] The temperature sampling circuit can simultaneously collect the real-time temperatures of the upper and lower formations and transmit them to the control circuit 15.

[0083] An embedded storage module is integrated on the control circuit 15 to record in real time the internal pressure of the oil pipe (real-time injection pressure), formation pressure (real-time formation pressure), real-time temperature data, and valve position state data of the ceramic combination valve during the injection process. The control circuit 15 internally includes a single-chip microcomputer, and a water injection scheme is preset inside the single-chip microcomputer.

[0084] The isolation drive sleeve 4 is connected to a live joint outer ring 7 through a live joint swivel 5, and the live joint outer ring 7 is connected to the lower sealing tail vertebra 11. A second limit ring 8 is sleeved outside the limit coupling rod 10, and a live joint inner ring 6 is sleeved outside the second limit ring 8.

[0085] During downhole water injection operations, water is injected into the well through surface equipment and tubing. The third pressure sensor detects the continuously changing pressure value, i.e., the real-time water injection pressure, and transmits it to the control circuit 15. The control circuit 15 matches the real-time water injection pressure with the internally preset pressure fluctuation coding signal. If the match is successful, it controls the start of the reduction motor 16 according to the water injection mode corresponding to the preset pressure fluctuation coding signal. The output shaft of the reduction motor 16 rotates to drive the isolation coupling 17, the measurement and control valve reducer 18, and the limit coupling rod 10 to move, and then drives the ceramic combination valve 19 to open or close, and injects water into the formation according to the corresponding water injection plan.

[0086] The battery pack 14, the control circuit 15, the reduction motor 16, etc. are isolated and driven from the measurement and control valve reducer 18 and its rear-end components by the isolation drive sleeve 4 and the isolation coupling 17, avoiding the use of dynamic seals. While ensuring long-term reliable sealing, it does not require a flat bearing to eliminate axial force, reducing the requirement for assembly concentricity. The limited torque transmission of the isolation coupling 17 also avoids damage to the valve components due to excessive torque. The torque output part of the isolation coupling 17, the measurement and control valve reducer 18, the first limit ring 9, the second limit ring 8, and the front end of the limit coupling rod 10 are sealed with an oil cavity, providing double protection against corrosion and lubrication.

[0087] In the present invention, the ceramic combination valve includes: a valve core 40 and a valve sleeve 41; the valve core 40 is inside the valve sleeve 41; two symmetric valve core upper holes 45 are provided on the valve core 40, and two valve sleeve upper holes 47 corresponding to the valve core upper holes 45 are provided on the valve sleeve 41; a first valve core lower hole 46 and a second valve core lower hole 46 are provided on the valve core 40, the first valve core lower hole 46 corresponds to the position of any one of the valve core upper holes 45, and the position of the second valve core lower hole 46 corresponds to the midpoint position between the two valve core upper holes 45; a valve sleeve lower hole 48 corresponding to the second valve core lower hole 46 is provided on the valve sleeve 41; bottom holes are provided at one end of the valve core 40 and the valve sleeve 41 away from the limit coupling rod 10; the valve core upper holes 45 and the valve sleeve upper holes 47 form an upper channel, and the first valve core lower hole 46, the second valve core lower hole 46, and the valve sleeve lower hole 48 form a lower channel.

[0088] In the embodiment of the present invention, as Figure 4 and Figure 5As shown, the clearance between the valve core 40 and the valve sleeve 41 is less than 1 micron, and there will be a slow drip only under the condition of 5 MPa pressure of pure water, which meets the sealing requirements in oilfield water injection and oil production; the valve sleeve 41 is arranged inside the lower sealing tail cone 11. A rotary slot 43 for connecting with the limit coupling rod 10 is arranged on the valve core 40; at one end of the valve sleeve 41 close to the limit coupling rod 10, a fixing slot 44 is arranged, and the fixing slot 44 is used to cooperate with the first limit ring 9 to be fixed inside the lower sealing tail cone 11. After the valve sleeve 41 is embedded into the lower sealing tail cone 11, the fixing slot 44 is blocked by the first limit ring 9 and cannot rotate.

[0089] Two sealing grooves 42 are arranged on the outer side wall of the valve sleeve 41, and sealing rings are arranged in the sealing grooves 42 to seal the clearance between the valve sleeve 41 and the inner wall of the sealing tail cone, preventing the injected water from entering the clearance between the two. The flat head at one end of the limit coupling rod 10 away from the measurement and control valve reducer 18 passes through the first limit ring 9 and the valve sleeve 41 and then inserts into the rotary slot 43 inside the valve core 40.

[0090] On the valve core 40, two valve core upper holes 45 are arranged opposite to each other; the valve core upper holes 45 are relatively closer to the limit coupling rod 10, and the valve core lower holes 46 are relatively farther from the limit coupling rod 10; among them, the first valve core lower hole 46 and any one of the valve core upper holes 45 are on the same axial straight line, and the second valve core lower hole 46 is in the middle of the two valve core upper holes 45 and is on the same circumferential straight line as the first valve core lower hole 46.

[0091] The control circuit controls the start of the reduction motor 16 to drive the valve core 40 to rotate to the corresponding angle through the isolation coupling 17, the measurement and control valve reducer 18 and the limit coupling rod 10, so that the positions of the valve core upper hole 45 and the valve sleeve upper hole 47 overlap, that is, the upper channel is opened, and / or the positions of the valve core lower hole 46 and the valve sleeve lower hole 48 overlap, that is, the lower channel is opened; the injected water enters the inside of the valve core 40 through the bottom opening at one end of the lower sealing tail cone 11 away from the isolation drive sleeve 4 and the bottom holes of the valve sleeve 41 and the valve core 40; after the upper channel is opened, the injected water is injected into the upper formation through the water distribution packer, and after the lower channel is opened, the injected water is injected into the lower formation from the water distribution packer.

[0092] In the present invention, the water distribution packer includes: a packer body; an upper layer water outlet channel 28 is arranged on the side wall of the packer body, and the upper layer water outlet channel 28 communicates with the upper formation and the upper channel respectively; a lower layer water injection channel 27 is arranged inside the side wall of the packer body, and the lower layer water injection channel 27 communicates with the lower formation and the lower channel respectively; a lower layer pressure transmission channel 26 is arranged inside the side wall of the packer body, one end of the lower layer pressure transmission channel 26 communicates with the pressure detection unit, and the other end communicates with the lower layer water injection channel 27; a bridge flow channel 25 is arranged inside the side wall of the packer body, one end of the bridge flow channel 25 communicates with the tubing string above the packer body, and the other end communicates with the tubing string below the packer body.

[0093] In an embodiment of the present invention, as Figure 3 shown, on the outer sidewall of the sensor short circuit 3 of the double-layer injection-production measurement and control valve, there are a first upper sealing ring 12 and a second upper sealing ring 33 that cooperate with the first upper sealing surface 20 and the second upper sealing surface 21 on the inner wall of the packer body for sealing; on the outer sidewall of the lower sealing tail vertebra 11, there are respectively a first lower sealing ring 34 and a second lower sealing ring 35 that cooperate with the first lower sealing surface 22 and the second lower sealing surface 23 on the inner wall of the packer body for sealing; on the sidewall of the packer body, there is a lower layer water outlet channel 29, and the lower layer water injection channel 27 communicates with the lower layer water outlet channel 29; the positions of the first lower sealing surface 22 and the second lower sealing surface 23 are between the upper layer water outlet channel 28 and the lower layer water outlet channel 29.

[0094] The bridge flow channel 25, the lower layer pressure transmission channel 26, and the lower layer water injection channel 27 are eight different-angle eccentric flow channels distributed on the circumferential sidewall of the packer body. Among them, there are 4 bridge flow channels 25. The injected water enters from the tubing above the packer body, passes through the bridge flow channels 25 and is injected below the packer body, and then returns upward from the bottom opening of the lower sealing tail vertebra 11 and enters the ceramic combination valve 19. The 4 bridge flow channels 25 are used to ensure sufficient downward water passage. There are 2 lower layer water injection channels 27 and 2 lower layer pressure transmission channels 26 respectively.

[0095] On the outside of the packer, there is a packer sealing rubber sleeve 30. The position of the upper layer water outlet channel 28 is on one side of the packer sealing rubber sleeve 30, and the position of the lower layer water outlet channel 29 is on the other side of the packer sealing rubber sleeve 30; the packer sealing rubber sleeve 30 is used to seal between the upper and lower formations.

[0096] When installing the double-layer injection-production measurement and control valve, insert it into the inside of the packer body. At this time, the first upper sealing ring 12 contacts and seals with the first upper sealing surface 20, the second upper sealing ring 33 contacts and seals with the second upper sealing surface 21. At the same time, the first lower sealing ring 34 contacts and seals with the second lower sealing surface 23, and the second lower sealing ring 35 contacts and seals with the second lower sealing surface 23, thereby dividing the inside of the packer body into two parts of space, corresponding to the upper formation and the lower formation respectively.

[0097] The upper channel of the ceramic combination valve 19 is between the first upper sealing ring 12 and the first lower sealing ring 34, and the lower channel is between the first lower sealing ring 34 and the second lower sealing ring 35. The upper layer water outlet channel 28 is between the second upper sealing surface 21 and the first lower sealing surface 22, and the lower layer water outlet channel 29 is between the second lower sealing surface 23 and the lower joint 32. The inlet of the lower layer water injection channel 27 is between the first lower sealing surface 22 and the second lower sealing surface 23 and corresponds to the lower channel.

[0098] In the present invention, the method for controlling the opening or closing of the internal ceramic combination valve according to a preset water injection scheme for layered water injection includes: when performing layered water injection, controlling the start of the reduction motor 16, driving the valve core 40 to rotate by different angles through the isolation coupling 17, the measurement and control valve reducer 18, and the limit coupling rod 10, so that the upper hole 45 of the valve core coincides with the upper hole 47 of the valve sleeve, and the lower hole 46 of the second valve core coincides with the lower hole 48 of the valve sleeve, or, the upper hole 45 of the valve core is offset from the upper hole 47 of the valve sleeve, while the lower hole 46 of the first valve core coincides with the lower hole 48 of the valve sleeve, or, the upper hole 45 of the valve core coincides with the upper hole 47 of the valve sleeve, while the lower holes 46 of the first and second valve cores are offset from the lower hole 48 of the valve sleeve, or, the upper hole 45 of the valve core and the upper hole 47 of the valve sleeve, and the lower hole 46 of the first valve core and the lower hole 48 of the valve sleeve are offset; the injected water sequentially passes through the bridge channel 25, the bottom opening of the lower sealing tail cone 11, the valve sleeve 41, and the bottom hole of the valve core 40 from the pipe string above the packer body, enters the inside of the valve core 40, and then enters the upper formation in the two layers through the upper channel and the upper layer water outlet channel 28, and / or, the injected water enters the lower formation in the two layers from the inside of the valve core 40 through the lower channel and the lower layer water injection channel 27.

[0099] In an embodiment of the present invention, when injecting water into the upper formation, the reduction motor 16 drives the valve core 40 to rotate until the upper channel is opened, and the injected water enters the upper layer water outlet channel 28 between the second upper sealing surface 21 and the first lower sealing surface 22, and is injected into the upper formation through the upper layer water outlet channel 28; when injecting water into the lower formation, the reduction motor 16 drives the valve core 40 to rotate until the lower channel is opened, and the injected water enters the lower layer water injection channel 27 from the lower channel of the ceramic combination valve 19, and then enters the lower layer water outlet channel 29 through the lower layer water injection channel 27, and is injected into the lower formation through the lower layer water outlet channel 29. When injecting water into the upper and lower formations simultaneously, control the ceramic combination valve 19 to rotate until the upper channel and the lower channel are opened simultaneously, and the injected water in the tubing string is injected into the upper and lower formations through the upper channel, the lower channel, the upper layer water outlet channel 28, and the lower layer water injection channel 27.

[0100] The specific process of layered injection by driving the valve core 40 to rotate is as follows:

[0101] If the initial relative angle between the valve core 40 and the valve sleeve 41 is 0°, then: at 0°, the upper holes 45 of the two valve cores coincide with the upper holes 47 of the two valve sleeves, and at the same time, the lower hole 46 of the second valve core coincides with the lower hole 48 of the valve sleeve; the injected water enters from the bottom hole of the valve core 40, passes through the upper hole 45 of the valve core, the upper hole 47 of the valve sleeve, and the lower hole 46 of the second valve core, the lower hole 48 of the valve sleeve, and the lower layer water injection channel 27 into the formation, that is, the upper channel and the lower channel are opened simultaneously.

[0102] When the spool 40 is rotated by an angle of 90°, the following occurs: The holes 45 on the two spools are misaligned with the holes 47 on the two valve sleeves. At the same time, the lower hole 46 of the second spool is misaligned with the lower hole 48 of the valve sleeve, and the lower hole 46 of the first spool overlaps with the lower hole 48 of the valve sleeve; The injected water enters from the bottom hole of the spool 40, passes through the lower hole 46 of the first spool, the lower hole 48 of the valve sleeve, and the lower injection channel 27 to enter the lower formation, that is, the lower channel is opened and the upper channel is closed.

[0103] When the spool 40 is rotated by an angle of 180°, the following occurs: The holes 45 on the two spools overlap with the holes 47 on the two valve sleeves. At the same time, the lower hole 46 of the first spool and the lower hole 46 of the second spool are misaligned with the lower hole 48 of the valve sleeve; The injected water enters from the bottom hole of the spool 40, passes through the upper hole 45 of the first spool, the upper hole 45 of the second spool, and the upper hole 47 of the valve sleeve to enter the upper formation, that is, the upper channel is opened and the lower channel is closed.

[0104] When the spool 40 is rotated by an angle of 270°, the following occurs: The holes 45 on the two spools are misaligned with the holes 47 on the two valve sleeves. At the same time, the lower hole 46 of the first spool and the lower hole 46 of the second spool are misaligned with the lower hole 48 of the valve sleeve, and both the upper channel and the lower channel are closed.

[0105] That is, when the spool 40 is rotated downward by 0° and 180°, the upper channel is opened; when the spool 40 is rotated downward by 90° and 270°, the upper channel is closed; when the spool 40 is rotated downward by 0° and 90°, the lower channel is opened; when the spool 40 is rotated downward by 180° and 270°, the lower channel is closed.

[0106] That is, when the spool 40 is rotated downward by 0°, 90°, 180°, and 270°, the states of the channels are respectively "open - open", "closed - open", "open - closed", "closed - closed". That is, it can realize the arbitrary opening and closing of the upper and lower channels, which is equivalent to a switch valve with two - way independent control, and can realize separate or simultaneous water injection for the upper and lower layers.

[0107] The probe of the second pressure sensor 52 and the end opening of the lower pressure transmission channel 26 away from the lower injection channel 27 are located between the first upper sealing ring 12 and the second upper sealing ring 33. The lower pressure transmission channel 26 is used to introduce the lower formation pressure to the position of the second pressure sensor 52 to facilitate the detection of the layer pressure.

[0108] All valves, flow paths, and channels in the double - layer injection - production measurement and control valve and the packer body are designed with a throttling differential pressure not greater than the diameter of a 15 - mm round hole, and can be fully used for separate - layer water injection and separate - layer oil production.

[0109] During the water - injection process, the pressure - detection unit and the temperature - detection unit collect real - time pressure and temperature data of the underground formation. The control circuit 15 controls the movement of the ceramic combination valve 19 through the reduction motor 16 for on - off control, injects water according to a predetermined plan, or automatically adjusts the water - injection plan according to the change of the real - time pressure data of the formation.

[0110] In the present invention, the method for detachably installing a double-layer injection-production measurement and control valve inside each water distribution packer includes: a clamping groove is provided on the double-layer injection-production measurement and control valve, and a seating clamping point 24 that cooperates with the clamping groove is provided inside the packer body; a plurality of packer bodies are arranged underground, and the diameter at the seating clamping point 24 inside each packer body is smaller than the diameter at the seating clamping point 24 inside the packer body above it by a predetermined value; a conventional packer 74 is arranged between two adjacent packer bodies; the double-layer injection-production measurement and control valve is sequentially lowered into the packer body from the wellhead in the order of increasing diameter at the clamping groove, and the installation is completed through the cooperation of the corresponding seating clamping point 24 and the clamping groove.

[0111] In an embodiment of the present invention, as Figure 1 shown, when there are multiple underground water injection formations, multiple packer bodies and double-layer injection-production measurement and control valves can be used in combination. For example, if there are six underground water injection formations, then three packer bodies are correspondingly lowered, and each packer body corresponds to two adjacent layers. The packer sealing rubber plug on the packer body separates the two adjacent formations corresponding to it. Then the underground part includes a conventional packer 74, a first-stage water distribution packer 71, a conventional packer 74, a second-stage water distribution packer 72, a conventional packer 74, and a third-stage water distribution packer 73 connected in sequence from top to bottom.

[0112] One double-layer injection-production measurement and control valve can be lowered into the center of each stage of water distribution packer 71, and the double-layer injection-production measurement and control valves inside each stage of water distribution packer are designed to be retrievable. The clamping groove on the double-layer injection-production measurement and control valve is arranged on the outer side wall of the lower sealing tail cone 11; the seating clamping point 24 is an annular protrusion on the inner wall of the packer body. When the double-layer injection-production measurement and control valve is inserted into the inside of the packer body, the seating clamping point 24 is snapped into the clamping groove to be seated in place. At this time, the first upper sealing surface 20 and the second upper sealing surface 21 are in contact with the first upper sealing ring 12 and the second upper sealing ring 33 for sealing, and the first lower sealing surface 22 and the second lower sealing surface 23 are in contact with the first lower sealing ring 34 and the second lower sealing ring 35 for sealing.

[0113] The double-layer injection-production measurement and control valve drives the ceramic combination valve to rotate through a reduction motor, can control the opening and closing of two independent water injection channels, realizes the water injection test and control of two layers, forms a dual-channel independent water injection unit, and performs the pressure and temperature test and storage of two layers, realizing multi-modal water injection of six layers.

[0114] The water distribution packer set adopts a full-bore decreasing structure design. The diameters of the seating points 24 inside the three packer bodies decrease successively from top to bottom. That is, the internal through-bore diameter of the packer body at the uppermost position is the largest, and the internal through-bore diameter of the packer body at the lowermost position is the smallest. And the diameter of the seating point inside each packer body is smaller than the diameter of the seating point inside the packer body above it by a predetermined value. Among them, the value of the predetermined value is 5 - 12 mm.

[0115] The diameter at the card slot on the lower sealing tail cone 11 of the double-layer injection-production measurement and control valve matches the diameter at the seating point inside the corresponding packer body; the upper sealing ring and the lower sealing tail cone 11 of the double-layer injection-production measurement and control valve are respectively provided with three corresponding matching sizes, such as large, medium, and small sizes. As long as the two components, the upper sealing ring and the lower sealing tail cone 11 of the double-layer injection-production measurement and control valve, are replaced, three double-layer injection-production measurement and control valves with decreasing sizes can be formed, and the diameter decreasing amplitude is 5 - 12 mm / level. In this way, on the same injection well, three sets of double-layer injection-production measurement and control valves can be installed to realize the injection measurement and control of six layers. When in use, they are put into the packer body from the wellhead in ascending order of their diameters, and the gravity setting can be realized.

[0116] For example: the standard through-bore diameter of the first-stage water distribution packer 71 is 54 mm, the through-bore diameter of the second-stage water distribution packer 72 is 47 mm, and the through-bore diameter of the third-stage water distribution packer 73 is 40 mm. The through-bore diameter decreasing amplitude is 5 - 12 mm / level; each water distribution packer set adopts a gravity-setting retrievable structure. The double-layer injection-production measurement and control valve can be naturally seated into the corresponding-size packer body in the well by gravity when put into the wellbore, without operation construction, and can be retrieved to the ground by a wireline testing vehicle. When all the double-layer injection-production measurement and control valves are in the retrieved state, the downhole string maintains a continuous through-bore diameter of ≥40 mm, meeting the full-well section passing requirements of downhole testing instruments such as distributed temperature sensors, ultrasonic imagers, and water absorption profile testers.

[0117] In the present invention, a communication unit is arranged inside the double-layer injection-production measurement and control valve. The communication unit is connected to the pressure detection unit and the temperature sampling circuit; the communication unit is used to transmit the data detected by the pressure detection unit and the temperature sampling circuit, as well as the data of the opening or closing state of the upper channel and / or the lower channel of the ceramic combination valve 19 controlled by the control circuit 15 according to the injection scheme, to the cloud server through a wireless transmission module.

[0118] In an embodiment of the present invention, a communication short - circuit 2 is further connected between the battery cylinder 1 and the sensor short - circuit 3. A communication unit is arranged inside the communication short - circuit 2. The communication unit is connected to a pressure detection unit, a temperature sampling circuit, and a control circuit 15. When the double - layer injection - production measurement and control valve is taken out to the ground, the communication unit is used to transmit the pressure data collected by the pressure detection unit, the temperature data collected by the temperature sampling circuit, and the parameter data of the control circuit 15 for controlling the reduction motor 16, that is, the opening or closing state data of the ceramic combination valve 19, to the cloud server through a wireless transmission module, so as to realize the back - transmission of stored data. Among them, the collected pressure data includes: a dynamic water injection pressure curve, that is, the real - time water injection pressure, and a static pressure decay curve, that is, the real - time formation pressure, which is used to evaluate the packer seal tightness through pressure transient analysis method and conduct well - testing interpretation of reservoir parameters. Among them, the communication short - circuit 2 is made of non - metal PEEK material, and wireless communication with the outside can be carried out without opening the double - layer injection - production measurement and control valve during data transmission.

[0119] In an embodiment of the present invention, for stratified water injection, the specific operation steps of the double - layer injection - production measurement and control valve are as follows: 1. According to the number of water - injection intervals, select several sets of double - layer injection - production measurement and control valves. If there are multiple sets of double - layer injection - production measurement and control valves, they must be in a relationship of decreasing outer diameter.

[0120] 2. Select a corresponding water - distribution packer group for each set of double - layer injection - production measurement and control valves, and separate the two groups with a set of conventional packers.

[0121] 3. Design one or more water - injection schemes through the cloud server to form a water - injection scheme group, that is, a water - injection control program. Before going down the well, when the double - layer injection - production measurement and control valve arrives at the well site, it will automatically download the water - injection scheme group composed of multiple water - injection schemes from the cloud server and completely copy it to the single - chip microcomputer program of the control circuit 15 of each double - layer injection - production measurement and control valve through the near - field wireless communication protocol (wireless transmission module).

[0122] 4. Design the pipe string structure and assemble the pipe string for operation to go down the well. At this time, the double - layer injection - production measurement and control valve can be pre - inserted into the corresponding water - distribution packer body and go down the well with the operation. If the double - layer injection - production measurement and control valve is not installed in the water - distribution packer body in advance, then all the double - layer injection - production measurement and control valves are put down from the wellhead in the order of first small diameter and then large diameter, and automatically sit into the corresponding water - distribution packer body through the cooperation of the card slot and the card point.

[0123] 5. After all the double - layer injection - production measurement and control valves are seated in place, the control circuit controls the reduction motor to start, and the ground equipment and the double - layer injection - production measurement and control valves in each underground layer section carry out water injection according to a unified water - injection scheme. The detection and control mechanism collects and records the operation pressure and temperature curves to complete the water - injection task.

[0124] 6. If it is necessary to replace the water injection plan, the surface and downhole equipment can stop water injection completely at a fixed time point every week or month. The surface equipment sends a pressure wave command, that is, the water injection forms a preset pressure fluctuation coding signal. All the double-layer injection-production measurement and control valves downhole receive the command. After the command transmission is completed, all the surface and downhole equipment inject water using the water injection plan corresponding to the coding signal. The cloud server can also send a predetermined pressure pulse coding command within a preset periodic time window (for example: 00:00-00:10 on Monday every week), and the double-layer injection-production measurement and control valves downhole synchronously enter the command receiving mode. The cloud server and the double-layer injection-production measurement and control valves downhole complete the confirmation of data transmission integrity through a verification algorithm.

[0125] 7. If data playback is required, or other operation construction or test tasks are needed, the double-layer injection-production measurement and control valves can be fished out in turn by a wireline testing vehicle and recovered to the surface.

[0126] 8. After each double-layer injection-production measurement and control valve reaches the surface, its internal control circuit 15 will recognize that its own pressure change reaches a predetermined pressure, such as 0 pressure, then control to connect to the cloud server through the wireless transmission module, automatically upload all the internal data to the server, and at the same time receive new commands, such as a water injection plan group, and clear the internal data.

[0127] In the embodiment of the present invention, the double-layer injection-production measurement and control valve and the water distribution packer can also be directly applied to the oil production construction process. For stratified oil production, the specific steps of the double-layer injection-production measurement and control valve are as follows:

[0128] 1. According to the number of oil production intervals, one set of double-layer injection-production measurement and control valves is selected for every two intervals. When using double-layer injection-production measurement and control valves on an oil well, there is no need for fishing, there is no limit on the number of sets, and there is no requirement for decreasing size.

[0129] 2. Select a corresponding production allocation packer group for each set of double-layer injection-production measurement and control valves, and use one set of conventional packers between the two groups.

[0130] 3. Design one or more production allocation plans through the cloud server to form a production allocation plan group, that is, a production allocation control program, and upload it to the cloud server. When the double-layer injection-production measurement and control valve reaches the well site, download the production allocation plan group from the cloud server and completely copy it into the single-chip microcomputer program of the control circuit 15 of each double-layer injection-production measurement and control valve.

[0131] 4. Design the string structure, assemble the string, insert the double-layer injection-production measurement and control valve into the corresponding production allocation packer group and fix it, and lower it into the well with the operation.

[0132] 5. After all the strings are lowered, assemble the wellhead and start stratified oil production; all the oil-producing intervals will start or close the intervals according to the designed production allocation plan, that is, control the upper channel and / or the lower channel to open or close, so as to realize stratified oil production.

[0133] During oil production, the upper-layer produced fluid will enter the upper channel inside the valve core 40 through the upper-layer water outlet channel 28, then enter the oil pipe below the lower sealing tail cone 11, and then return to the ground after passing through the bridge flow channel 25; the lower-layer produced fluid will enter the lower-layer water injection channel 27 through the lower-layer water outlet channel 29, then enter the lower channel inside the valve core 40 and enter the oil pipe below the lower sealing tail cone 11, and finally return to the ground after passing through the bridge flow channel 25.

[0134] The bottom opening of the lower sealing tail cone 11 enters the inside of the valve core 40, passes through the upper channel and / or the lower channel, and records the operating pressure and temperature curves.

[0135] 6. If it is necessary to change the production allocation plan, the surface equipment will send instructions to all downhole double-layer injection-production measurement and control valves using the technology of the variable-frequency interference communication device and its communication method for pumping wells, specifically referring to the technical solution with the patent application number: 2020115132742, and use a new production allocation plan in the production allocation plan group for layer section switch control. If data playback is required, or if operation and construction are required, then all double-layer injection-production measurement and control valves will be recovered to the surface.

[0136] In the present invention, a passive cloud-controlled high-pressure valve 69 is provided on the water injection pipeline at the wellhead. By controlling the opening or closing of the passive cloud-controlled high-pressure valve 69, the injection flow rate and pressure are adjusted; wherein, the passive cloud-controlled high-pressure valve 69 includes: a high-pressure valve body 49, a DC motor 54, a solar power supply mechanism, and a remote control module; the DC motor 54 is connected to a first-stage reducer 53, the first-stage reducer 53 is connected to a second-stage reducer 52, and the second-stage reducer 52 is connected to the high-pressure valve body 49 through a coupling 50; the solar power supply mechanism is respectively connected to the DC motor 54 and the remote control module; the DC motor 54 is connected to the remote control module, and the remote control module is used to control the start of the DC motor 54 according to the received control instruction, and drive the high-pressure valve body 49 to move through the first-stage reducer 53 and the second-stage reducer 52;

[0137] And / or, the solar power supply mechanism includes: a cylindrical solar outer sleeve 55 composed of a plurality of solar panels and a battery connected to the solar panels; the DC motor 54, the first-stage reducer 53, the second-stage reducer 52, the remote control module, and the coupling 50 are installed inside the solar outer sleeve 55.

[0138] In the present invention, the output torque of the DC motor 54 is determined, and the driving torque after being reduced by the first-stage reducer 53 and the second-stage reducer 52 is determined according to the output torque; the ball valve opening torque of the high-pressure valve body 49 is determined, and the parameters of the DC motor 54, the first-stage reducer 53, and the second-stage reducer 52 are determined according to the ball valve opening torque and the driving torque.

[0139] In the embodiment of the present invention, asFigure 6 As shown, during use, the high-pressure valve body 49 is installed on the water injection pipeline at the wellhead of the water injection well. The cloud server converts the opening and closing sequence numbers in the water injection plan into a specific opening control sequence of the passive cloud-controlled high-pressure valve 69 by adopting a specific pressure coding format. The cloud server sends a valve control instruction (opening control sequence) to the remote control module through the wireless transmission module. After receiving the instruction, the remote control module controls the DC motor 54 to start. After passing through the first-stage reducer 53 and the second-stage reducer 52, the ball valve in the high-pressure valve body 49 is driven by the coupling 50 to rotate to a predetermined angle (90°), so that the high-pressure valve is opened or closed. When the high-pressure valve is opened, the injected water is injected into the well through the high-pressure valve body 49, forming a pressure pulse coding instruction, which is transmitted to the downhole double-layer injection-production measurement and control valve through the pressure fluctuation in the pipe string.

[0140] Among them, the present invention adopts a high transmission efficiency design, that is, the second-stage reducer 52 is above the high-pressure valve body 49, the first-stage reducer 53 is above the second-stage reducer 52, and the DC motor 54 is above the first-stage reducer 53. The torque output from the DC motor 54 is transmitted to the upper end of the high-pressure valve body 49, and the transmission efficiency is greater than 95%, which can maximize the transmission efficiency. At the same time, a two-stage reduction design is adopted, that is, the first-stage reducer 53 and the second-stage reducer 524, while ensuring the output torque of the high-pressure valve, reduce the size of the reducer and avoid its own loss.

[0141] Among them, the wireless transmission module can be a short-range wireless network (Zigbee protocol) data connection. The wireless transmission module is connected to devices such as a near-field server, facilitating mutual measurement and control of adjacent devices; and / or the wireless transmission module is a remote 2G / 4G / satellite network connection, connected to the cloud server through the remote network to receive cloud instructions. At the same time, the remote control module uploads the operation parameter data of the DC motor 54, the reducer and the valve to the cloud server through the wireless transmission module.

[0142] The drive of the high-pressure valve body 49 adopts a low-voltage and large-current design. The highest working voltage of the internal circuit of the valve body is 4.2V, and the maximum working current of the motor is 20A, while maintaining a safe low voltage and maximizing the drive power as much as possible.

[0143] It is set to use a DC motor 54 with 3.6V, 72W, and 20A current, and the motor speed is 26,000 rpm. The motor drives and rotates unidirectionally, and finally drives the ball valve to switch between the open and closed states every time it rotates 90 degrees.

[0144] Among them, the output torque of the DC motor 54 is calculated according to the empirical formula of motor power and torque:

[0145] Motor power P (kW) = torque T (N·m) * motor speed n (rpm) / 9550;

[0146] It can be seen from this that the output torque of the DC motor 54 is 0.026 N·m.

[0147] Calculated with the reduction ratio of the first-stage reducer 53 being 139 and the reduction ratio of the second-stage reducer 52 being 72, after two-stage reduction, considering the transmission efficiency of 95% and the efficiency of the two-stage reducer of 80%, the driving torque after reduction is approximately 150 Nm, and the rotational speed is about 2.6 rpm. That is, for each switch operation, it takes about 6 seconds to rotate 90 degrees.

[0148] The calculation formula for the opening torque of the ball valve of the high-pressure valve body 49 can be expressed as:

[0149] T = d * d * π / 4 * P * k * d;

[0150] In the formula: T is the opening torque, N·m; d is the diameter of the ball valve, m; P is the opening pressure; k is the friction coefficient, generally taken as 0.15.

[0151] By matching the obtained opening torque of the ball valve and the driving torque after reduction, it can be determined whether the parameters of the DC motor 54 for oil production can meet the requirements. If not, the parameters need to be adjusted again; that is, according to the above formula for calculating the opening torque of the ball valve, it can be calculated that a ball valve with DN32 and 35 MPa requires a torque of 132 N·m. Therefore, it can be determined that the torque of 150 N·m after reduction of the DC motor 54 with 3.6 V, 72 W, and 20 A and the two-stage reducer with a reduction ratio of 72 can meet the usage requirements.

[0152] The solar jacket 55 is a cylindrical solar jacket 55 composed of 8 solar panels with 5.5 V and 230 mA. A waterproof top cover 57 is provided at the top of the solar jacket 55, and the bottom end is connected to the top of the high-pressure valve body 49. Inside the solar jacket 55, around the first-stage reducer 53 and the DC motor 54 is a battery cavity 68, where a rechargeable battery pack is installed, and the battery is connected to the DC motor 54 and the remote control module.

[0153] Considering that at most only two solar panels of the solar jacket 55 receive sunlight at the same time, and calculated according to 8 hours per day, when 2 panels work simultaneously, the daily charging amount is 230 mA * 2 * 8 h ≈ 3.6 Ah of electricity. Considering half cloudy and rainy days, the average daily charging amount is calculated as 1.8 Ah.

[0154] The rechargeable battery pack in the battery cavity 68 adopts a parallel design of 22 18650 rechargeable batteries with 3.6 V and a rated capacity of 2.7 Ah. The total battery capacity is: 2.7 Ah * 22 = 59.4 Ah. If the battery is completely discharged, it takes about 33 days for the solar energy to fully charge the battery pack.

[0155] When the DC motor 54 opens the valve, the maximum working current is about 20 A. When closing the valve, the current is about 5 A. Taking the average working current of about 10 A, each valve opening or closing action takes 6 seconds, so the average power consumption for each switching action is 0.017 Ah. That is, when the battery is fully charged and without considering solar charging replenishment, the valve can be continuously switched 59.4 / 0.017 ≈ 3494 times.

[0156] Calculated according to the charging capacity of the solar panel, the photovoltaic charging can keep the high-pressure valve switched 1.8 / 0.017 ≈ 106 times a day.

[0157] If it is not a full-open or full-close operation, but a micro-adjustment, the time for each valve adjustment is calculated as 0.4 seconds. The photovoltaic charging can ensure 1600 adjustments per day, that is, the valve can be adjusted once per minute, which can meet the requirements for most application scenarios that do not require overly frequent adjustments.

[0158] The top of the high-pressure valve body 49 is connected to the coupling support 51, and the outer screw of the coupling support 51 is connected to and supports the solar jacket 55. Inside the solar jacket 55, a coupling 50 is arranged inside the coupling support 51. The coupling 50 and the coupling support 51 support and connect the secondary reducer 52, the primary reducer 53, the DC motor 54 and the circuit board 56 of the remote control module upward in sequence; the bottom end of the coupling 50 and the coupling support 51 is connected to the top of the high-pressure valve body 49. In the flow channel part of the high-pressure valve body 49, it is sequentially connected and composed of a left connecting clamp 64, a left connecting body 65, the high-pressure valve body 49, a right connecting body 61, and a right connecting clamp 60 from left to right. The top of the coupling support 51 is provided with a positioning Hall mounting hole, and the positioning Hall sensor 58 is connected to the output shaft of the inside of the mounting hole and the secondary reducer 524. The positioning Hall sensor 58 is used to detect the rotation angle of the ball valve in the high-pressure valve body 49 driven by the secondary reducer 52, and transmit the rotation angle data to the cloud server through the remote control module. On the bracket between the secondary reducer 52 and the primary reducer 53, a counting Hall mounting hole is provided, and the counting Hall sensor 59 is connected to the output shaft of the mounting hole and the primary reducer 53. The counting Hall sensor 59 is used to detect the rotation number data of the primary reducer 53 and transmit it to the cloud server through the remote control module.

[0159] A first pressure gauge 66 and a first pressure gauge connection channel 67 are installed on the left connecting body 65; a second pressure gauge 52 and a second pressure gauge connection channel 63 are installed on the right connecting body 61.

[0160] The first pressure gauge 66 is connected to the remote control module through the first pressure gauge connection channel 67. The probe of the first pressure gauge 66 communicates with the inside of the left connection body 65. The first pressure gauge 66 detects the first real-time pressure of the fluid in the left connection body 65 and transmits it to the cloud server through the remote control module. The second pressure gauge 52 is connected to the remote control module through the second pressure gauge connection channel 63. The probe of the second pressure gauge 52 communicates with the inside of the right connection body 61. The second pressure gauge 52 detects the second real-time pressure of the fluid in the right connection body 61 and transmits it to the cloud server through the remote control module.

[0161] An integrated linear flowmeter 70 for measuring the injection water flow rate is also installed on the injection pipeline at the wellhead. The integrated linear flowmeter 70, the passive cloud-controlled high-pressure valve 69, and the cloud server form an integrated surface control system. The passive cloud-controlled high-pressure valve 69 also has the function of collecting the back-end pressure. The two form a surface closed-loop control system for the water injection system, which can perform specific flow rate injection, specific pressure injection, or injection stop for the whole well.

[0162] Whether for operation needs or test needs, once the double-layer injection-production measurement and control valve is fished out to the ground, the data in it will be automatically transmitted back to the cloud server. During the entire historical working period, for each layer section switching action of the ceramic combination valve, by judging whether the adjacent layer section pressure (formation real-time pressure) follows, that is, whether it changes accordingly, the sealing condition of the water distribution packer can be evaluated. During the entire historical working period, after any layer section is closed, the pressure drop curve of that layer section will be recorded for a period of time. If the time is long enough, well testing interpretation and analysis can be carried out. Of course, if well testing interpretation and analysis are definitely needed, then before the double-layer injection-production measurement and control valve is fished out to the ground, the injection plan can be artificially stopped for each layer section for a long enough time to obtain a complete pressure drop curve.

[0163] A multi-modal stratified water injection system for oilfield injection wells according to the present invention realizes precise stratified water injection operations through the collaborative control of ground water injection adjustment equipment and downhole double-layer injection-production measurement and control valves. Each downhole double-layer injection-production measurement and control valve is preset to execute a water injection plan, and the corresponding water injection channels of each layer section are opened and closed according to a preset program; the ground equipment synchronously executes a homologous water injection plan, and stratified water injection is achieved through dynamic regulation of flow or pressure. The process control dimension includes a dual-parameter system: (1) precise regulation based on flow monitoring; (2) adaptive adjustment based on formation pressure. Through a combined regulation method, four basic water injection modes can be formed, namely balanced flow water injection, pulsating flow water injection, stable pressure water injection, cyclic pressure water injection, and any combined application of the above modes. The innovation of the present invention lies in constructing a closed-loop intelligent control system, which breaks through the traditional stratified water injection and upgrades it to a multi-modal composite water injection process, and can be compatible with various operation requirements such as water injection / injection of polymer / gas injection. Its technical advantages are reflected in: 1) improving the injection control accuracy of the layer section; 2) dynamically adapting to complex well conditions and heterogeneous reservoirs; 3) reducing the ineffective circulation by more than 25% through intelligent matching of injection-production parameters; 4) the recovery rate can be increased by 10% - 20%, which is especially suitable for the enhanced development of low-permeability and high-water-cut reservoirs.

[0164] Aiming at the technical defects of the traditional stratified water injection process, such as single control mode, serious interlayer interference, and lagging data feedback, the present invention proposes and realizes intelligent multi-modal stratified water injection. Its technical solution achieves a technical breakthrough through the following innovations: I. System architecture innovation: 1. Dual-closed-loop control system: Construct a "ground intelligent adjustment - downhole dynamic execution" dual-closed-loop control system. The ground unit consists of a high-precision integral linear flowmeter 70 (±0.3% reading accuracy) and a passive cloud-controlled high-pressure valve 69, which are locally interconnected through short-range wireless communication and interact with the cloud server in real time through a remote wireless network. 2. Modular downhole actuator: The three-stage gradient water distribution packer group is made of high-strength alloy, and the temperature resistance level is increased to above 175°C; the double-layer injection-production measurement and control valve adopts a professionally customized ceramic combination valve (switching life > 10 6times) and a multi-parameter sensor array (pressure ±0.1%FS, temperature ±0.1°C); 3. Cableless communication system: Realize two-way communication between the ground and the underground based on pressure pulse coding technology, and adopt forward error correction coding to ensure the reliability of 99.9% of the instruction transmission. II. Innovation in control methods: 1. Four-dimensional water injection mode library: Balanced flow mode: Realize layer flow balance based on the fuzzy PID algorithm (volatility < 3%); Pulsating flow mode: Support a layer-by-layer injection sequence with adjustable frequency; Stable pressure mode: Establish a stable reservoir pressure gradient model (resolution 0.01 MPa / m); Periodic pressure mode: The simplest and most stable method to increase the water injection sweep volume and improve the recovery rate; 2. Adaptive control strategy: Develop a dynamic correction algorithm for the water absorption indicator curve (R² > 0.97), specifically refer to the technical solution with the patent application number: 2020115132742; Construct a prediction model for the health of packers based on a neural network system (accuracy > 95%); Implement a dynamic ranking mechanism for the priority of water injection intervals. III. Innovation in diagnostic analysis: 1. Real-time seal diagnosis: Detect packer leakage through pressure derivative analysis; 2. Reservoir parameter inversion: Use an improved multi-flow well test interpretation algorithm to inversely calculate the formation coefficient (error < 8%); 3. Injection-production benefit evaluation: Establish an evaluation system for the injection water efficiency index (IWEI) to realize automatic optimization of the water injection plan.

[0165] The technical advantages of the present invention have been verified through on-site tests in multiple blocks of oilfields, and are specifically embodied as follows: 1. Breakthrough in technical performance: The multi-modal water injection process adapts to different well conditions and intervals, achieving optimal efficiency and productivity; the interval water injection volume is accurately counted, and the control accuracy reaches ±2.5% (the traditional process requires ±15%); the ineffective water injection cycle is reduced by 37.5% (measured data). 2. Significant economic benefits: The use of pulsating flow or periodic pressure injection methods can increase the swept volume of water injection, form a variable pressure field in the oil layer, mobilize the potential of the reservoir, and the recovery rate is increased by 19.2% (production data of the test area for 12 months); the annual maintenance cost per well is reduced by 75% (compared with the cable system); full-flow large-channel water injection, without throttling valves and no throttling nozzles, with the minimum energy loss; the packer seal verification and well test pressure measurement are completed synchronously, without the need for separate testing; the system MTBF is increased to 8500 hours (the industry average is 2000 hours). 3. Advantages in engineering implementation: The test channel maintains a full diameter of Φ40mm (the traditional system ≤ Φ28mm); the measurement and control valves can be fished out in sequence with a steel wire rope, and can be seated in place by dropping by gravity from the wellhead. Other systems basically require well workovers; it is compatible with polymer injection (viscosity upper limit of 5000 mPa·s) and CO2 displacement operations, avoiding the throttling problem caused by the original small-diameter nozzles. 4. Intelligent innovation: Supports access to the remote intelligent control platform (supports 2G, 4G and satellite network access). 5. Improvement in safety and reliability: The interlayer interference rate is reduced to 4.3% (the traditional process is 41.6%); pressure control mode water injection can gradually eliminate interlayer contradictions and gradually optimize the geological form; the data acquisition integrity rate reaches 98% (compared with the cable system of 80%).

[0166] The embodiments of the present invention have been described above. The above description is exemplary and not exhaustive, and is not limited to the disclosed embodiments. Many modifications and variations are obvious to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The choice of terms used herein is intended to best explain the principles of the embodiments, practical applications, or improvements to the technology in the market, or to enable other ordinary skill in the art to understand the embodiments disclosed herein.

Claims

1. A multi-modal hierarchical water injection system, characterized in that, Including: Lower a water distribution packer to a predetermined position in the wellbore. Each of the water distribution packers corresponds to two intervals. A double-layer injection-production measurement and control valve is removably seated inside each of the water distribution packers, and the double-layer injection-production measurement and control valve can be fished to the ground; When the double-layer injection-production measurement and control valve is on the ground, the cloud server preloads different preset water injection schemes into the double-layer injection-production measurement and control valve through a wireless transmission module. Each preset water injection scheme includes a corresponding water injection mode and water injection parameters corresponding to this mode. According to the preset water injection scheme, control the opening or closing of the internal ceramic combination valve to perform layered water injection; wherein, the water injection modes at least include: balanced flow water injection, pulsating flow water injection, stable pressure water injection, and periodic pressure water injection; Among them, for the balanced flow water injection and pulsating flow water injection, the injection volume of the interval is controlled to be a predetermined injection volume, and for the stable pressure water injection and periodic pressure water injection, the injection pressure of the interval is controlled to be a predetermined injection pressure; among them, the balanced flow water injection and stable pressure water injection are continuous and uninterrupted water injection modes, and the pulsating flow water injection and periodic pressure water injection are fluctuating intermittent water injection modes.

2. The multimodal layered water injection system according to claim 1, wherein: The balanced flow water injection is: determine the wellbore injection pressure according to the interval with the worst water absorption and the wellbore water absorption indication curve, and use this wellbore injection pressure to inject water into each interval; the double-layer injection-production measurement and control valve collects the real-time formation pressure, and determines the shutdown time ratio of each interval according to it, and injects water according to this shutdown time ratio, so that the injection volume within the interval period reaches the predetermined injection volume; after each cycle of water injection is completed, readjust the shutdown time ratio and the wellbore injection pressure according to the actual injection volume of the interval, so that the actual injection volume within the interval period reaches the predetermined injection volume; The pulsating flow water injection is: sequentially perform polling water injection on each interval at a predetermined maximum injection pressure. If the predetermined injection volume cannot be completed within one water injection cycle, combine several intervals with similar water absorption characteristics for water injection; The stable pressure water injection is: inject water into each interval at a predetermined minimum injection pressure. The double-layer injection-production measurement and control valve collects the real-time formation pressure, and judges whether the real-time formation pressure is not equal to the predetermined formation pressure. If so, adjust the water injection by controlling the opening or closing of the ceramic combination valve to make the real-time formation pressure equal to the predetermined formation pressure; The periodic pressure water injection is: determine the minimum wellbore injection pressure according to the highest formation pressure of each interval, and inject water into the interval according to this minimum wellbore injection pressure; the double-layer injection-production measurement and control valve controls periodic water injection operations according to the predetermined water injection pressure period of its corresponding interval. During each cycle of water injection, when the real-time formation pressure reaches the corresponding predetermined maximum pressure of the interval, stop injecting after maintaining the injection for a predetermined time. When the real-time formation pressure drops to the predetermined pressure, control the next cycle of water injection; If it is necessary to switch the water injection mode, the double-layer injection-production measurement and control valve receives a pressure pulse coding instruction transmitted from the ground, and injects water according to the water injection scheme corresponding to this instruction.

3. The multimodal hierarchical water injection system according to claim 1, characterized in that, The double-layer injection-production measurement and control valve includes: a sensor stub (3), an isolation drive sleeve (4), and a lower sealing tail cone (11) connected in sequence; The sensor stub (3) is provided with a pressure detection unit for detecting the real-time formation pressure and injection pressure, a temperature sampling circuit for detecting the real-time formation temperature, and a control circuit (15) connected to the pressure detection unit and the temperature detection unit; The isolation drive sleeve (4) is provided with a reduction motor (16), an isolation coupling (17), a measurement and control valve reducer (18), and a limit coupling rod (10) connected in sequence. The limit coupling rod (10) is connected to the ceramic combination valve (19), and the reduction motor (16) is connected to the control circuit (15); The ceramic combination valve (19) is arranged inside the lower sealing tail cone.

4. The multimodal hierarchical water injection system according to claim 3, wherein The ceramic combination valve includes: a valve core (40) and a valve sleeve (41); The valve core (40) is located inside the valve sleeve (41); Two symmetrically arranged upper holes (45) are provided on the valve core (40), and two upper holes (47) corresponding to the upper holes (45) on the valve core are provided on the valve sleeve (41); A first lower hole (46) and a second lower hole (46) are provided on the valve core (40). The first lower hole (46) corresponds to the position of any one of the upper holes (45) on the valve core, and the position of the second lower hole (46) corresponds to the midpoint position between the two upper holes (45) on the valve core; A lower hole (48) corresponding to the second lower hole (46) on the valve core is provided on the valve sleeve (41); Bottom holes are provided at one ends of the valve core (40) and the valve sleeve (41) away from the limit coupling rod (10); The upper holes (45) on the valve core and the upper holes (47) on the valve sleeve form an upper channel, and the first lower hole (46), the second lower hole (46), and the lower hole (48) on the valve sleeve form a lower channel.

5. The multimodal hierarchical water injection system according to claim 4, wherein The water distribution packer includes: a packer body; An upper layer water outlet channel (28) is provided on the side wall of the packer body. The upper layer water outlet channel (28) communicates with the upper layer formation and the upper channel respectively. A lower layer water injection channel (27) is provided inside the side wall of the packer body. The lower layer water injection channel (27) communicates with the lower layer formation and the lower channel respectively; A lower layer pressure transmission channel (26) is provided inside the side wall of the packer body. One end of the lower layer pressure transmission channel (26) communicates with the pressure detection unit, and the other end communicates with the lower layer water injection channel (27); A bridge flow channel (25) is provided inside the side wall of the packer body. One end of the bridge flow channel (25) communicates with the tubing string above the packer body, and the other end communicates with the tubing string below the packer body.

6. The multi-modal hierarchical water injection system according to claim 5, wherein The method for detachably installing a double-layer injection-production measurement and control valve inside each water distribution packer includes: A clamping groove is provided on the double-layer injection-production measurement and control valve, and a seating clamping point (24) matched with the clamping groove is provided inside the packer body; A plurality of packer bodies are arranged underground. The diameter of each seating clamping point (24) inside the packer body is smaller than a fixed value compared with the diameter of the seating clamping point (24) inside the packer body above it; A conventional packer (74) is provided between two adjacent packer bodies; The double-layer injection and production control valve is sequentially placed from the wellhead into the packer body according to the diameter of the slot from small to large, and the installation is completed by matching the corresponding seat clamping point (24) with the slot.

7. The multimodal hierarchical water injection system according to claim 5, wherein The method for performing stratified water injection by controlling the opening or closing of the internal ceramic combination valve according to a preset water injection scheme includes: When performing stratified water injection, the control reduction motor (16) is started, and the valve core (40) is driven to rotate at different angles through the isolation coupling (17), the measuring and control valve reducer (18) and the limit coupling rod (10), so that the valve core upper hole (45) and the valve sleeve upper hole (47), the second valve core lower hole (46) and the valve sleeve lower hole (48) are overlapped, or the valve core upper hole (45) and the valve sleeve upper hole (47) are staggered, and at the same time, the first valve core lower hole (46) and the valve sleeve lower hole (48) are overlapped, or the valve core upper hole (45) and the valve sleeve upper hole (47) are overlapped, and at the same time, the first and second valve core lower holes (46) and the valve sleeve lower hole (48) are staggered, or the valve core upper hole (45) and the valve sleeve upper hole (47), the first valve core lower hole (46) and the valve sleeve lower hole (48) are staggered; The injected water enters the interior of the valve core (40) from the tubing string above the packer body through the bridge flow channel (25), the bottom opening of the lower sealing tail cone (11), the valve sleeve (41) and the bottom hole of the valve core (40), and enters the upper formation of the two layers through the upper channel and the upper water outlet channel (28), and / or, the injected water enters the lower formation of the two layers from the interior of the valve core (40) through the lower channel and the lower water injection channel (27).

8. The multi-modal hierarchical water injection system according to claim 3, characterized in that A communication unit is provided inside the double-layer injection and production measurement and control valve, and the communication unit is connected to the pressure detection unit and the temperature sampling circuit; The communication unit is used to transmit the data detected by the pressure detection unit and the temperature sampling circuit, as well as the data of the opening or closing status of the upper channel and / or lower channel of the ceramic combination valve (19) controlled by the control circuit (15) according to the water injection scheme to the cloud server through the wireless transmission module.

9. The multimodal stratified water injection system according to any one of claims 1 to 8, characterized in that: A passive cloud-controlled high-pressure valve (69) is provided on the water injection pipeline at the wellhead, and the injection flow rate and pressure are adjusted by controlling the passive cloud-controlled high-pressure valve (69) to open or close; The passive cloud-controlled high-pressure valve (69) comprises: a high-pressure valve body (49), a DC motor (54), a solar power supply mechanism, and a remote control module; The DC motor (54) is connected to a primary reducer (53), the primary reducer (53) is connected to a secondary reducer (52), and the secondary reducer (52) is connected to the high-pressure valve body (49) via a coupling (50); The solar power supply mechanism is connected to the DC motor (54) and the remote control module respectively; The DC motor (54) is connected to the remote control module, and the remote control module is configured to control the start of the DC motor (54) according to the received control instruction, and drive the high-pressure valve body (49) to rotate through the first-stage reducer (53) and the second-stage reducer (52); and / or, The solar power supply mechanism includes: a cylindrical solar outer jacket (55) composed of a plurality of solar panels and a battery connected to the solar panels; the DC motor (54), the first-stage reducer (53), the second-stage reducer (52), the remote control module, and the coupling (50) are installed inside the solar outer jacket (55).

10. The multimodal hierarchical water injection system according to claim 9, wherein: Determine the output torque of the DC motor (54), and determine the driving torque after being reduced by the first-stage reducer (53) and the second-stage reducer (52) according to the output torque; Determine the ball valve opening torque of the high-pressure valve body (49), and determine the parameters of the DC motor (54), the first-stage reducer (53), and the second-stage reducer (52) according to the ball valve opening torque and the driving torque.

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