Segmented plugging and control mining structure and segmented plugging and control mining method

Abstract

The invention discloses a segmented blocking and control mining structure and a segmented blocking and control mining method.The segmented blocking and control mining structure comprises a segmented control mining mode and a segmented blocking and control mode, and when the segmented blocking and control mining structure is in the segmented control mining mode, a sliding sleeve in any production cabin is opened; when the segmented plugging control mining structure is in a segmented plugging control mode, the sliding sleeve in any high-water-content production cabin is closed, or the sliding sleeve in any high-water-content production cabin is opened, the sliding sleeves in other non-high-water-content production cabins are closed, and the sliding sleeves in the other non-high-water-content production cabins are opened. A water plugging agent is injected into the oil pipe and is injected into a water outlet stratum for plugging through the sliding sleeve in the high-water-content production cabin, the segmented plugging control and production structure can effectively cut off a water channeling path, can perform segmented control and production, can directly regulate and control the oil-water output proportion, can perform plugging control on the high-water-content branch shaft or the production cabin, and can be used for controlling the water outlet stratum. The purposes of reducing ineffective output of water and stabilizing effective output of oil can be effectively achieved, and the purposes of stabilizing oil and controlling water are achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of oil and gas exploitation, in particular to a segmented plugging and control production structure and a segmented plugging and control production method. BACKGROUND

[0002] For weak natural water drive, medium and low permeability and strong heterogeneity of edge water reservoir, multi-lateral well or increasing branches on the basis of old well can improve productivity and increase the producing degree of the reservoir. If the reservoir fracture is developed or the well location is close to the oil-water interface or the well section is locally high permeability, the overall water cut of the branch well will rise quickly, and the water rate of the branch close to the water direction will be higher than that of other branches, which will inhibit the development and production of the remaining oil in other branch well zones. At the same time, there are problems of liquid supply profile and uneven water rise in different well sections of the same branch, which will cause water channeling of the whole well.

[0003] The conventional water control mode performs chemical or mechanical water plugging on the last branch wellbore of the fast water rise branch well, which can inhibit the rapid rise of water cut to a certain extent, but the pertinence is poor and it is difficult to achieve fine regulation and control of the reservoir. The water control opportunity can only be selected after water channeling, and the whole well is implemented when the water cut is high or very high, which cannot realize flow field regulation and balanced displacement at medium and low water cut. The plugged branch or other branches are not maximally produced. SUMMARY

[0004] The technical problem to be solved by the present application is to provide a segmented plugging and control production structure and a segmented plugging and control production method.

[0005] The technical solution adopted by the present application to solve the technical problem is: a segmented plugging and control production structure is constructed, which includes a plurality of branch wellbores, the plurality of branch wellbores include a first branch wellbore, a second branch wellbore,..., and an n-th branch wellbore; the segmented plugging and control production structure further includes a round production device, the round production device includes a tubing, a filter protection pipe, and a plurality of packoff assemblies; the tubing is used for inserting into the n-th branch wellbore, the filter protection pipe is sleeved on the outer periphery of the tubing; the packoff assemblies are installed on the outer periphery of the tubing to separate the plurality of branch wellbores into a plurality of production cabins, and the part of the tubing located in each production cabin is provided with at least one sliding sleeve, and the production cabin and the branch wellbore opposite thereto are communicatively arranged; the segmented plugging and control production structure includes a segmented control production mode and a segmented plugging and control mode, when the segmented plugging and control production structure is in the segmented control production mode, the sliding sleeve in any production cabin is opened; when the segmented plugging and control production structure is in the segmented plugging and control mode, the sliding sleeve in any production cabin with high water cut is closed, or the sliding sleeve in any production cabin with high water cut is opened, and the sliding sleeves in other production cabins without high water cut are closed, and the tubing injects a water plugging agent and injects the water plugging agent into the water producing formation through the sliding sleeve in the production cabin with high water cut to plug.

[0006] In some embodiments, n is a natural number less than or equal to 10.

[0007] In some embodiments, the segmented plugging and control production structure further comprises a main branch wellbore connected and communicated with the nth branch wellbore; a casing shoe and a casing are arranged in the main branch wellbore; and at least one of the packoff assemblies is arranged in the casing.

[0008] In some embodiments, each of the packoff assemblies comprises an external packoff and an internal packoff. The filter protection pipe comprises a plurality of filter protection pipe segments, and each of the filter protection pipe segments is connected with two adjacent external packoffs at two ends thereof. The internal packoffs are arranged on the oil pipe in an axial direction, and at least part of the external packoffs seal the annular space between the internal packoffs and the inner wall of the casing and / or the annular space between the internal packoffs and at least part of the wall of the branch wellbore.

[0009] In some embodiments, the sliding sleeve comprises an intelligent electrically controlled sliding sleeve, and the segmented plugging and control production structure further comprises a control cable penetrating through the external packoff and connected with the sliding sleeve.

[0010] In some embodiments, the external packoff is a liquid-swelling packoff.

[0011] In some embodiments, the internal packoff is a liquid-swelling packoff.

[0012] In some embodiments, the end of the oil pipe is provided with a plug.

[0013] The application further provides a segmented plugging and control production method applied to the segmented plugging and control production structure of any of the above embodiments, and the segmented plugging and control production method comprises the following steps. S10. Performing segmented control production mode, sequentially opening the sliding sleeves of the production cabins and performing segmented control production. S20. Performing segmented plugging and control mode, closing the sliding sleeve in any one of the production cabins with high water cut or opening the sliding sleeve in any one of the production cabins with high water cut and closing the sliding sleeves in other production cabins without high water cut, injecting a water plugging agent from the oil pipe and into the water formation through the sliding sleeve in the production cabin with high water cut to plug.

[0014] In some embodiments, in step S20, the water content of the oil liquid produced by the production compartment is obtained, it is determined whether the water content is high water content, if the water content is high water content, the sliding sleeve in the production compartment corresponding to the high water content is closed, or the sliding sleeve in the production compartment with high water content is opened, and the sliding sleeve in the production compartment with non-high water content is closed, the water plugging agent is injected from the oil pipe and injected into the water producing formation through the sliding sleeve in the production compartment with high water content for plugging.

[0015] The implementation of the present application has the following beneficial effects: the segmented plugging and control production structure includes a plurality of branch wellbores, the plurality of branch wellbores include a first branch wellbore, a second branch wellbore,..., and an nth branch wellbore; the segmented plugging and control production structure further includes a rotating production device, the rotating production device includes an oil pipe, a filter protection pipe, and a plurality of packer assemblies; the oil pipe is used for being inserted into the nth branch wellbore, the filter protection pipe is sleeved on the outer periphery of the oil pipe; the packer assemblies are installed on the outer periphery of the oil pipe to separate the plurality of branch wellbores into a plurality of production compartments, and the oil pipe located in each production compartment is provided with at least one sliding sleeve, and the production compartment and the branch wellbore opposite to the production compartment are in communication; the segmented plugging and control production structure includes a segmented control production mode and a segmented plugging and control mode, when the segmented plugging and control production structure is in the segmented control production mode, the sliding sleeve in any one of the production compartments is opened; when the segmented plugging and control production structure is in the segmented plugging and control mode, the sliding sleeve in any one of the production compartments with high water content is closed, or the sliding sleeve in any one of the production compartments with high water content is opened, and the sliding sleeve in the production compartment with non-high water content is closed, the water plugging agent is injected from the oil pipe and injected into the water producing formation through the sliding sleeve in the production compartment with high water content for plugging, the segmented plugging and control production structure can effectively cut off the water channeling path, can perform segmented control production, can directly regulate and control the oil and water production ratio, and can plugging and control the branch wellbore or the production compartment with high water content, so that the invalid production of water is reduced, the effective production of oil is stabilized, and the goal of stabilizing oil and controlling water is achieved. BRIEF DESCRIPTION OF DRAWINGS

[0016] In order to more clearly illustrate the technical solutions of the present application, the present application will be further described below in combination with the drawings and embodiments. It should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can also be obtained without creative labor. In the drawings: Figure 1 is a structural schematic diagram of the segmented plugging and control production structure in some embodiments of the present application. DETAILED DESCRIPTION

[0017] In order to have a clearer understanding of the technical features, objectives and effects of the present application, the specific embodiments of the present application will be described in detail with reference to the drawings. In the following description, it should be understood that the directions or positional relationships indicated by "front", "back", "upper", "lower", "left", "right", "vertical", "horizontal", "vertical", "horizontal", "top", "bottom", "inner", "outer", "head", "tail" and the like are based on the directions or positional relationships shown in the drawings, constructed and operated in a particular direction, and are only for the convenience of describing the technical solutions, and are not intended to indicate that the devices or elements referred to must have a particular direction, and therefore cannot be understood as a limitation on the present application.

[0018] It should also be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connection", "fixing", "setting" and the like should be broadly understood, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements or the interaction relationship between two elements. When an element is referred to as "on" or "under" another element, the element can be "directly" or "indirectly" located on the other element, or one or more intervening elements can be present. The terms "first", "second", "third" and the like are only for the convenience of describing the technical solutions, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features with "first", "second", "third" and the like can be explicitly or implicitly included one or more of the features. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0019] In the following description, specific details such as specific system structures, techniques, etc. are presented for the purpose of explanation, not for the purpose of limitation, so as to thoroughly understand the embodiments of the present application. However, it should be clear to those skilled in the art that the present application can also be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits and methods are omitted to avoid unnecessary details that hinder the description of the present application.

[0020] The present application provides a segmented plugging and production structure, which comprises a plurality of branch wellbores, the plurality of branch wellbores comprising a first branch wellbore, a second branch wellbore,..., and an nth branch wellbore; the segmented plugging and production structure further comprises a rotary production device, the rotary production device comprising a tubing, a filter protection pipe, and a plurality of packoff assemblies. The filter protection pipe includes but is not limited to a screen pipe and a perforated pipe.

[0021] The tubing is inserted into the nth branch wellbore, and the filter protection pipe is sleeved on the outer periphery of the tubing. The packoff assembly is installed on the outer periphery of the tubing to separate the several branch wellbores into a plurality of production compartments, and the part of the tubing located in each production compartment is provided with at least one sliding sleeve. The production compartment and the branch wellbore opposite to it are in communication. For example, the production compartments can include a first production compartment, a second production compartment, a third production compartment, and an nth production compartment. The first production compartment can be in communication with the first branch wellbore, and the second production compartment can be in communication with the second branch wellbore.

[0022] The segmented control and production structure includes a segmented control mode and a segmented plugging mode. When the segmented control and production structure is in the segmented control mode, the sliding sleeve in any production compartment is opened to carry out oil exploitation. Specifically, the oil in the production compartment is non-high water cut oil, which can be low water cut oil or medium water cut oil. For example, when the first production compartment is low water cut, the sliding sleeve in the first production compartment can be opened for exploitation.

[0023] When the segmented control and production structure is in the segmented plugging mode, the sliding sleeve in any high water cut production compartment is closed, or the sliding sleeve in any high water cut production compartment is opened, and the sliding sleeves in other non-high water cut production compartments are closed. The tubing injects water plugging agent and injects it into the water producing formation through the sliding sleeve in the high water cut production compartment for plugging. For example, when the third production compartment is high water cut, the sliding sleeve in the third production compartment can be closed, or the sliding sleeve in the third production compartment is opened, and the sliding sleeves in other non-high water cut production compartments (such as the first production compartment, the second production compartment, etc.) are closed. The tubing injects water plugging agent and injects it into the water producing formation through the sliding sleeve in the high water cut third production compartment for plugging.

[0024] In some embodiments, n is a natural number less than or equal to 10. Preferably, n is greater than or equal to 3 and less than or equal to 10.

[0025] In some embodiments, the segmented control and production structure further includes a main branch wellbore connected and in communication with the nth branch wellbore. A casing shoe and a casing are arranged in the main branch wellbore. At least one packoff assembly is arranged in the casing.

[0026] In some embodiments, each packoff assembly includes an external packoff and an internal packoff. The filter protection pipe includes a plurality of filter protection pipe segments. Each filter protection pipe segment has two ends connected to two adjacent external packoffs, respectively. The internal packoff is installed on the tubing in the axial direction of the tubing. At least part of the external packoff blocks the annular space between the internal packoff and the inner wall of the casing, and / or at least part of the external packoff blocks the annular space between the internal packoff and the well wall of at least part of the branch wellbore.

[0027] In some embodiments, the sliding sleeve comprises an intelligent electrically controlled sliding sleeve, and the segmented plugging and control production structure further comprises a control cable penetrating the external casing packer to be connected with the sliding sleeve.

[0028] In some embodiments, the external casing packer is a liquid-swelling packer.

[0029] In some embodiments, the internal casing packer is a liquid-swelling packer.

[0030] In some embodiments, the end of the tubing is provided with a plug.

[0031] The present application also provides a segmented plugging and control production method applied to the segmented plugging and control production structure of any of the above embodiments, which comprises the following steps: S10. performing a segmented control production mode, sequentially opening the sliding sleeves of the production cabins for segmented control production; specifically, the oil liquid of the production cabin is a non-high water cut oil liquid, which can be a low water cut oil liquid or a medium water cut oil liquid, for example, when the first production cabin is of low water cut, the sliding sleeve in the first production cabin can be opened for production. The "sequentially" herein can be set according to actual needs, for example, the first production cabin can be produced first, and then the second production cabin.

[0032] S20. performing a segmented plugging and control mode, closing the sliding sleeve in any one production cabin of high water cut, or opening the sliding sleeve in any one production cabin of high water cut and closing the sliding sleeves in other production cabins of non-high water cut, injecting a water plugging agent from the tubing and injecting it into the water-producing formation through the sliding sleeve in the production cabin of high water cut for plugging. For example, when the third production cabin is of high water cut, the sliding sleeve in the third production cabin can be closed, or the sliding sleeve in the third production cabin is opened, and the sliding sleeves in other production cabins of non-high water cut (such as the first production cabin, the second production cabin, etc.) are closed, a water plugging agent is injected from the tubing and injected into the water-producing formation through the sliding sleeve in the third production cabin of high water cut for plugging.

[0033] In some embodiments, in step S20, the water cut of the oil liquid produced by the production cabin is obtained, it is judged whether the water cut is high, if the water cut is high, the sliding sleeve in the production cabin corresponding to the high water cut is closed, or the sliding sleeve in the production cabin of high water cut is opened, and the sliding sleeves in other production cabins of non-high water cut are closed, a water plugging agent is injected from the tubing and injected into the water-producing formation through the sliding sleeve in the production cabin of high water cut for plugging.

[0034] In some embodiments, the water cut of the oil liquid produced by the production cabin is obtained, it is judged whether the water cut is high, if the water cut is high, the sliding sleeve in the production cabin corresponding to the high water cut is closed, or the sliding sleeve in the production cabin of high water cut is opened, and the sliding sleeves in other production cabins of non-high water cut are closed, a water plugging agent is injected from the tubing and injected into the water-producing formation through the sliding sleeve in the production cabin of high water cut for plugging.

[0035] The segmented plugging and production structure and the segmented plugging and production method can effectively cut off water channeling paths, can be segmented for production control, can directly regulate and control oil and water production ratios, can plug and control high water cut branch wellbores or production compartments, can effectively achieve "reducing the ineffective production of water and stabilizing the effective production of oil", and can achieve the goal of stabilizing oil and controlling water.

[0036] The following shows an embodiment of the segmented plugging and production structure of the present application.

[0037] Referring to Figure 1 The present application shows a segmented plugging and production structure, which comprises a first branch wellbore 10, a second branch wellbore 20, a third branch wellbore 30, and a round production device 40. The round production device 40 comprises a tubing 41, a filter protection pipe 42, a first packoff assembly 43, a second packoff assembly 44, a third packoff assembly 45, and a fourth packoff assembly 46. The tubing 41 is inserted into the third branch wellbore 30, and the filter protection pipe 42 is sleeved on the outer periphery of the tubing 41. The first packoff assembly 43, the second packoff assembly 44, the third packoff assembly 45, and the fourth packoff assembly 46 are installed on the outer periphery of the tubing 41 to divide the third branch wellbore 30 into a first production compartment A, a second production compartment B, a third production compartment C, and a fourth production compartment D. A pipe section of the tubing 41 located in the first production compartment A is provided with a first sliding sleeve 411, a pipe section of the tubing 41 located in the second production compartment B is provided with a second sliding sleeve 412, a pipe section of the tubing 41 located in the third production compartment C is provided with a third sliding sleeve 413, and a pipe section of the tubing 41 located in the fourth production compartment D is provided with a fourth sliding sleeve 414.

[0038] The first branch wellbore 10 is in communication with the first production compartment A, and the second branch wellbore 20 is in communication with the second production compartment B.

[0039] The segmented plugging and production structure can effectively cut off water channeling paths, can be segmented for production control, can directly regulate and control oil and water production ratios, can plug and control high water cut branch wellbores or production compartments, can effectively achieve "reducing the ineffective production of water and stabilizing the effective production of oil", and can achieve the goal of stabilizing oil and controlling water. In the present application, the first branch wellbore 10 can be the first branch wellbore constructed, the second branch wellbore 20 is a wellbore constructed after the first branch wellbore 10, and the third branch wellbore 30 is the last wellbore constructed. For the convenience of understanding the technical solution of the present application, the common port of the first branch wellbore 10, the second branch wellbore 20, and the third branch wellbore 30 is regarded as the port of the third branch wellbore 30. The port of the third branch wellbore 30 is inside the oil layer, for example, the port of the third branch wellbore 30 is about 2000-3000 meters below the horizontal plane.

[0040] In the present application, the segmented plugging and production structure adopts a multi-lateral design of the first lateral wellbore 10, the second lateral wellbore 20, the third lateral wellbore 30, etc., which can cover multiple dispersed oil-bearing areas, and may also encounter different water layer distributions. If the water cut of a certain lateral (such as the second lateral wellbore 20) increases sharply due to water flooding, the sliding sleeve of the lateral (such as the second lateral wellbore 20) can be closed separately, without affecting the production of other oil-bearing laterals (such as the first lateral wellbore 10 and the third lateral wellbore 30), thereby avoiding the situation that a single high water cut lateral drags down the production of the whole well, and making the oil production more stable. Of course, the number of lateral wellbores can be selected according to actual needs, which is not specifically limited here.

[0041] In some embodiments, the production mode can include: (1) segmented lateral production of new laterals: a multi-lateral well structure is constructed in new well production, and laterals are reasonably arranged at the root to form a multi-antenna layout extending to the reservoir. After implementing compartment treatment on each lateral, each production compartment is produced in turn according to the rotation production strategy. After the main borehole is drilled into multiple laterals, compartment planning is completed, and different parts of the reservoir are fully utilized by alternating production, which can significantly improve the production capacity and the degree of reserve utilization compared with traditional horizontal wells. (2) segmented lateral production of new laterals based on old wells: in order to tap the remaining oil between old wells, multi-lateral boreholes are drilled in the open hole horizontal section by means of suspended slotting, etc., and the reservoir area corresponding to the laterals is compartmented after open hole completion. After the old well is transformed, multiple production compartments are divided, the segmented compartment of the new lateral is divided according to the reservoir characteristics, and the alternating production plan of different laterals is made, and the high-capacity low-water production compartment is produced first.

[0042] In the present application, the well type of the segmented plugging and production structure forms a three-dimensional lateral network (the first lateral wellbore 10, the second lateral wellbore 20, the third lateral wellbore 30) through multiple sidetracking (sidetracking point 1, sidetracking point 2), which breaks through the reservoir contact limit of straight wells or single lateral wells, and can more fully cover different blocks of heterogeneous reservoirs, providing a structural basis for "rotation production" and "plugging and production".

[0043] In some embodiments, the tubing 41 is a channel for lifting oil and gas from the downhole to the ground surface, and is a carrier for transporting crude oil.

[0044] In some embodiments, the filter protection pipe 42 (or perforated pipe) is a completion tool, which filters formation sand, provides a drainage channel, and ensures effective oil production in the open hole section. The filter protection pipe 42 includes but is not limited to a screen pipe, a perforated pipe.

[0045] In some embodiments, the segmented control production structure further includes a main branch wellbore connected and communicated with the third branch wellbore 30; a casing shoe 47 and a casing 48 are arranged in the main branch wellbore; and the first packoff assembly 43 is arranged in the casing 48. The casing 48 can be used to reinforce the wellbore wall, prevent formation collapse, and provide a "stable installation environment" for packoff assemblies and sliding sleeves, thereby ensuring the sealing effect of the packoff assembly. If the wellbore wall collapses, the packoff assembly may not be able to effectively isolate. The casing shoe 47 guides the casing 48 to be lowered and seals the annular space between the casing 48 and the formation, further preventing "interlayer channeling" and assisting the packoff assembly in strengthening the reliability of "oil-water isolation". Specifically, the casing shoe 47 is a structure at the lowermost end of the casing, which guides and fixes the casing 48 to ensure its stable position in the wellbore. The casing 48 reinforces the wellbore wall, prevents collapse, and isolates different formations to provide an installation basis for packoff assemblies, sliding sleeves, and other tools.

[0046] In some embodiments, the first packoff assembly 43, the second packoff assembly 44, the third packoff assembly 45, and the fourth packoff assembly 46 can achieve a "physical isolation wall" between the water layer and the oil layer. Specifically, the first packoff assembly 43, the second packoff assembly 44, the third packoff assembly 45, and the fourth packoff assembly 46 are downhole sealing tools that separate different well sections / formations, prevent fluid channeling, and ensure independent control of each branch / well section.

[0047] Further, the first packoff assembly 43 includes a first tubing external packoff 431 and a first tubing internal packoff 432, the second packoff assembly 44 includes a second tubing external packoff 441 and a second tubing internal packoff 442, the third packoff assembly 45 includes a third tubing external packoff 451 and a third tubing internal packoff 452, and the fourth packoff assembly 46 includes a fourth tubing external packoff 461 and a fourth tubing internal packoff 462.

[0048] The filter protection pipe 42 includes a first filter protection pipe section 421, a second filter protection pipe section 422, and a third filter protection pipe section 423; the first filter protection pipe section 421 is connected to the first tubing external packoff 431 and the second tubing external packoff 441, respectively; the second filter protection pipe section 422 is connected to the second tubing external packoff 441 and the third tubing external packoff 451, respectively; and the third filter protection pipe section 423 is connected to the third tubing external packoff 451 and the fourth tubing external packoff 461, respectively.

[0049] The first tubing inner packer 432, the second tubing inner packer 442, the third tubing inner packer 452, and the fourth tubing inner packer 462 are installed on the oil pipe 41 in axial spacing along the oil pipe 41.

[0050] The first tubing outer packer 431 blocks the annular space between the first tubing inner packer 432 and the inner wall of the casing 48, the second tubing outer packer 441 blocks the annular space between the second tubing inner packer 442 and the well wall of the third branch wellbore 30, the third tubing outer packer 451 blocks the annular space between the third tubing inner packer 452 and the well wall of the third branch wellbore 30, and the fourth tubing outer packer 461 blocks the annular space between the fourth tubing inner packer 462 and the well wall of the third branch wellbore 30.

[0051] In the embodiment, the tubing inner packer and the tubing outer packer can seal the annular space between the oil pipe and the casing, the oil pipe and the filter protection pipe (or different casing sections), and separate the wellbore into multiple independent "layers / branch units". For example, if a branch encounters a water layer, the packer can "isolate" the branch from other oil-bearing branches to prevent water from the water layer from flowing into the oil layer unit, thereby cutting off the "water channeling" path in space and laying the foundation for subsequent "selective production and oil control".

[0052] In the embodiment, the filter protection pipe 42 can be used to isolate the open hole well wall from the oil pipe 41, and the open hole well wall allows the oil layer to be "directly contacted" with the wellbore, increases the oil and gas seepage area, and improves the oil production efficiency (basis for stabilizing oil). Further, the open hole well wall is an uncased well section (usually a reservoir section), which can be completed with an open hole or a filter protection pipe to increase the oil and gas inflow area. The filter protection pipe 42 (or perforated pipe) "prevents sand" in the open hole section: allows oil and gas to pass through, blocks sand particles from entering the wellbore (sand particles will clog the oil pipe 41 and wear equipment), and ensures that the production channel is long-term unobstructed, allowing oil to be continuously and stably produced.

[0053] In some embodiments, the first sliding sleeve 411, the second sliding sleeve 412, the third sliding sleeve 413, and the fourth sliding sleeve 414 are intelligent electric control sliding sleeves, which are controlled to open / close by an electric signal, are core execution components of "round production" and "plugging and control production", and control the on / off of the oil flow channel.

[0054] In some embodiments, when any production cabin has high water content, the corresponding sliding sleeve of the production cabin is opened, the corresponding sliding sleeve of the other production cabin is closed, the chemical agent (water shutoff agent) 50 is injected into the oil pipe 41 at the wellhead, the chemical agent (water shutoff agent) 50 blocks the water-producing formation, solves the dimensional water production problem of the formation, and realizes oil increase. For example, when the third production cabin C has high water content, the third sliding sleeve 413 is opened, the first sliding sleeve 411, the second sliding sleeve 412 and the fourth sliding sleeve 414 are closed, the chemical agent (water shutoff agent) 50 is injected into the oil pipe 41 at the wellhead, the chemical agent (water shutoff agent) 50 blocks the water-producing formation, solves the dimensional water production problem of the formation, and realizes oil increase. Alternatively, for example, when the third production cabin A and the second production cabin B have high water content, the first sliding sleeve 411 and the second sliding sleeve 412 are opened, the third sliding sleeve 413 and the fourth sliding sleeve 414 are closed, the chemical agent (water shutoff agent) 50 is injected into the oil pipe 41 at the wellhead, the chemical agent (water shutoff agent) 50 blocks the water-producing formation, solves the dimensional water production problem of the formation, and realizes oil increase.

[0055] When a certain branch wellbore (such as the first branch wellbore 10) or a certain production cabin (such as the first production cabin A) has high water content (more water production and less oil production), the segmented isolation effect of the packer is used to inject the chemical agent (water shutoff agent) 50 into the branch wellbore (such as the first branch wellbore 10) or the production cabin (such as the first production cabin A), to accurately block the water-producing formation and reduce invalid water production, thereby improving the crude oil production. This mechanism solves the problem of "one flooding all flooding" in traditional commingled production wells, and achieves the goal of "water shutoff and production control, efficiency improvement and oil increase".

[0056] Further, the segmented plugging and control production structure further comprises a control cable 49 penetrating the first external packer 431, the second external packer 441, the third external packer 451 and the fourth external packer 461, and the control cable 49 is in sealed cooperation with the external packer. Specifically, the control cable 49 is a control sliding sleeve switch signal cable, which can be used to transmit electrical signals and remotely / automatically control the opening and closing of the intelligent electric control sliding sleeve, thereby realizing the flow control of each branch well section.

[0057] The control cable 49 is connected with the first sliding sleeve 411, the second sliding sleeve 412, the third sliding sleeve 413 and the fourth sliding sleeve 414 to control the working state of the first sliding sleeve 411, the second sliding sleeve 412, the third sliding sleeve 413 and the fourth sliding sleeve 414, which includes the opening of the sliding sleeve, the closing of the sliding sleeve and the opening degree of the sliding sleeve.

[0058] The control cable 49 is connected with the control platform on the ground. The ground transmits electrical signals to the downhole sliding sleeve (such as an intelligent electric control sliding sleeve) through the control cable 49 to remotely control the opening / closing of the sliding sleeve. When the water cut of a certain branch / layer increases (more water and less oil), the corresponding sliding sleeve can be closed to cut off the fluid (mainly water) production of the unit; if a certain branch has "low water cut and high oil cut", the sliding sleeve is kept open to allow continuous oil production.

[0059] This "intelligent production selection" can accurately regulate the fluid contribution of each branch and directly achieve "controlling water (closing high water cut sections) and stabilizing oil (opening high oil cut sections)".

[0060] In some embodiments, the first tubing external packer 431, the second tubing external packer 441, the third tubing external packer 451, and the fourth tubing external packer 461 are liquid-swelling packers.

[0061] In some embodiments, the first tubing internal packer 432, the second tubing internal packer 442, the third tubing internal packer 452, and the fourth tubing internal packer 462 are liquid-swelling packers.

[0062] In some embodiments, the end of the tubing 41 is provided with a plug 410. The plug 410 is used to block the end of the tubing 41 to prevent fluid leakage and ensure that the oil flow is transported upward along the tubing 41. Specifically, the plug 410 can strengthen the "directional control" of the fluid, ensure that the fluid can only flow from the reservoir → the filter protection pipe 42 → the sliding sleeve → the tubing 41 by blocking the end of the branch, avoid "uncontrolled leakage" from the end of the branch, and make the sliding sleeve more accurate in regulating "oil and water production" (if the end leaks, the "on / off" function of the sliding sleeve will be weakened).

[0063] The segmented blocking and control production structure can block water channeling through physical isolation, combine sliding sleeve regulation to balance displacement, effectively inhibit local water channeling problems, and its core mechanism is: physical separation - inhibit water channeling path; sliding sleeve regulation - optimize displacement efficiency; energy balance - delay edge and bottom water breakthrough. It solves the core contradiction of "dispersed remaining oil, fast watered-out, and fast decline" in strong heterogeneous reservoirs and provides an economic and effective enhanced oil recovery path.

[0064] In some embodiments, through the combination of sliding sleeve + packer assembly + control cable, the "rotational production" of each branch wellbore is realized: for example, first open the first sliding sleeve 411 of the first production cabin A to produce the corresponding formation; after a period of time (for example, one week, which can be selected and set according to actual needs), close the first sliding sleeve 411 of the first production cabin A and open the second sliding sleeve 412 of the second production cabin B to switch the production object; similarly, the third sliding sleeve 413 of the third production cabin C can be switched. This way can avoid premature water-out of a single branch, balance the use of each layer reserves, and prolong the effective production period of a single well.

[0065] The segmented plugging and production structure expands reservoir contact through a multi-lateral structure, evenly produces reserves through round production, and controls invalid water production through segmented water plugging, thereby realizing efficient development of the multi-lateral well and being an innovative structure for improving recovery of a heterogeneous reservoir.

[0066] In some embodiments, the application further discloses a segmented plugging and production method applied to the segmented plugging and production structure of any of the above embodiments, and the segmented plugging and production method comprises the following steps. S10. A segmented production control mode is executed, and the sliding sleeves of the production compartments are opened in sequence to perform segmented production control; for example, the opening and closing states of the first sliding sleeve 411, the second sliding sleeve 412, the third sliding sleeve 413, and the fourth sliding sleeve 414 are controlled to realize round production and combined production of the first production compartment A, the second production compartment B, the third production compartment C, and the fourth production compartment D.

[0067] S20. A segmented plugging and production control mode is executed, and the sliding sleeve in any production compartment with a high water cut is closed or the sliding sleeve in any production compartment with a high water cut is opened and the sliding sleeves in other production compartments without a high water cut are closed, a water plugging agent is injected from the oil pipe and injected into the water-producing formation through the sliding sleeve in the production compartment with a high water cut to plug.

[0068] In some embodiments, the segmented plugging and production method further comprises the following steps. S20: The opening degrees of the first sliding sleeve 411, the second sliding sleeve 412, the third sliding sleeve 413, and the fourth sliding sleeve 414 are controlled to realize production liquid control of the first production compartment A, the second production compartment B, the third production compartment C, and the fourth production compartment D.

[0069] The sequence of the above step S10 and the above step S20 can not be in sequence, and can be selected and adjusted according to actual needs, which is not specifically limited here.

[0070] In some embodiments, in S10, the following steps are included. S11: The first sliding sleeve 411 is opened, and the second sliding sleeve 412, the third sliding sleeve 413, and the fourth sliding sleeve 414 are closed.

[0071] S12: The first sliding sleeve 411 and the second sliding sleeve 412 are opened, and the third sliding sleeve 413 and the fourth sliding sleeve 414 are closed.

[0072] S13: The first sliding sleeve 411, the second sliding sleeve 412, and the third sliding sleeve 413 are opened, and the fourth sliding sleeve 414 is closed.

[0073] S14: The first sliding sleeve 411 and the third sliding sleeve 413 are opened, and the second sliding sleeve 412 and the fourth sliding sleeve 414 are closed.

[0074] S15: opening the first sliding sleeve 411 and the fourth sliding sleeve 414, and closing the second sliding sleeve 412 and the third sliding sleeve 413.

[0075] S16: opening the first sliding sleeve 411, the third sliding sleeve 413 and the fourth sliding sleeve 414, and closing the second sliding sleeve 412.

[0076] S17: opening the first sliding sleeve 411, the second sliding sleeve 412, the third sliding sleeve 413 and the fourth sliding sleeve 414.

[0077] S18: opening the second sliding sleeve 412, and closing the first sliding sleeve 411, the third sliding sleeve 413 and the fourth sliding sleeve 414.

[0078] S19: opening the second sliding sleeve 412 and the third sliding sleeve 413, and closing the first sliding sleeve 411 and the fourth sliding sleeve 414.

[0079] S110: opening the second sliding sleeve 412 and the fourth sliding sleeve 414, and closing the third sliding sleeve 413 and the fourth sliding sleeve 414.

[0080] S111: opening the second sliding sleeve 412, the third sliding sleeve 413 and the fourth sliding sleeve 414, and closing the first sliding sleeve 411.

[0081] S112: opening the third sliding sleeve 413, and closing the first sliding sleeve 411, the second sliding sleeve 412 and the fourth sliding sleeve 414.

[0082] S113: opening the third sliding sleeve 413 and the fourth sliding sleeve 414, and closing the first sliding sleeve 411 and the second sliding sleeve 412.

[0083] S114: opening the fourth sliding sleeve 414, and closing the first sliding sleeve 411, the second sliding sleeve 412 and the third sliding sleeve 413.

[0084] The steps S11-S114 can be performed in any order, and the sliding sleeves can be controlled according to actual needs.

[0085] In some embodiments, in step S20, the water content of the oil produced by the first production chamber A, the second production chamber B, the third production chamber C or the fourth production chamber D is obtained, and it is determined whether the water content is high. If the water content is high, the sliding sleeve in the production chamber corresponding to the high water content is closed.

[0086] Wherein, the high water cut is generally greater than 80%, and greater than 95% is extra high water cut. The staff can sample and detect the produced liquid to obtain the water cut of the produced liquid. If the water cut is high water cut, the sliding sleeve in the production chamber corresponding to the high water cut is closed. For example, when the water cut of the produced liquid in the first production chamber A is high water cut, the first sliding sleeve 411 is closed. The water cut of the produced liquid in the second production chamber B, the third production chamber C and the fourth production chamber D is low water cut (generally less than 20%) or medium water cut (generally between 20%-80%), so the second sliding sleeve 412, the third sliding sleeve 413 and / or the fourth sliding sleeve 414 can be opened to produce oil in the second production chamber B, the third production chamber C and the fourth production chamber D.

[0087] In some embodiments, the segmented plugging and control production method further comprises the step S30 of obtaining the water cut of the oil produced by the first production chamber A, the second production chamber B, the third production chamber C or the fourth production chamber D, judging whether the water cut is high water cut, if the water cut is high water cut, the sliding sleeve of the production chamber corresponding to the high water cut is closed, and the chemical agent (water plugging agent) 50 is injected into the oil pipe 41 at the wellhead to plug the water-producing formation. The problem of dimensional water production of the formation can be solved to achieve oil increase.

[0088] For example, when the water cut in the third production chamber C is high, the third sliding sleeve 413 is opened, and the first sliding sleeve 411, the second sliding sleeve 412 and the fourth sliding sleeve 414 are closed. The chemical agent (water plugging agent) 50 is injected into the oil pipe 41 at the wellhead to plug the water-producing formation, solve the problem of dimensional water production of the formation, and achieve oil increase. Alternatively, for example, when the water cut in the third production chamber A and the second production chamber B is high, the first sliding sleeve 411 and the second sliding sleeve 412 are opened, and the third sliding sleeve 413 and the fourth sliding sleeve 414 are closed. The chemical agent (water plugging agent) 50 is injected into the oil pipe 41 at the wellhead to plug the water-producing formation, solve the problem of dimensional water production of the formation, and achieve oil increase.

[0089] When a certain branch wellbore (such as the first branch wellbore 10) or a certain production chamber (such as the first production chamber A) has high water cut (more water production and less oil production), the segmented isolation effect of the packer is used to inject the chemical agent (water plugging agent) 50 into the branch wellbore (such as the first branch wellbore 10) or the production chamber (such as the first production chamber A) to accurately plug the water-producing formation and reduce invalid water production, thereby improving the crude oil production. This mechanism solves the problem of "one flooding all flooding" in traditional commingled production wells, and achieves the goal of "water plugging and production control, efficiency improvement and oil increase".

[0090] In an embodiment, in a strong heterogeneous, reservoir fracture development, well location near oil-water interface, local high permeability zone in well section, weak natural water drive edge water reservoir, the oil layer thickness is 8.5 meters, the crude oil viscosity is 5.5 centipoise, and the permeability is 12-55 mD.

[0091] First, the existing branch well last branch (third branch wellbore 30) is segmented mechanically controlled water according to the actual drilling physical property difference, the first production cabin A and the second production cabin B are combined into a joint production section, and the third production cabin C and the fourth production cabin D form an alternating production unit, by periodically switching the unit with slow water content rise and low degree of utilization, the different branch control reserves in the well area are fully utilized, balanced displacement is realized, and the oil displacement range is increased.

[0092] Before the measures, the daily liquid production of the branch well is 952 m³ / d, the daily oil production is 52.6 m³ / d, and the water cut is 94.5%; after the measures, the branch cabin is closed, the second production cabin B, the third production cabin C and the fourth production cabin D are closed, only the first production cabin A is produced, the maximum daily oil increase is 63.9 m³ / d, the average daily oil increase is 29.1 m³ / d, the water cut is reduced by 11.6% at most, and the recoverable reserves are increased by 32,000 m³, and the oil increase and water reduction effect is obvious.

[0093] The segmented plugging and control production method expands the reservoir contact through the multi-branch structure, evenly utilizes the reserves through round production, and controls the invalid water production through segmented water plugging, realizes the efficient development of the multi-branch well, and is an innovative method for improving the recovery of the heterogeneous reservoir.

[0094] The segmented plugging and control production structure and the segmented plugging and control production method of the application mainly aim at the weak natural energy edge water drive reservoir, especially the reservoir with strong heterogeneity and obvious difference in water energy in different directions, the branch wellbore is segmented mechanically controlled water, a plurality of independent controllable production cabins are formed, the yield of each cabin can be adjusted, the interference between the cabins can be reduced or eliminated, and effective water control can be realized.

[0095] Compared with the prior art of passive, single and general water control, the segmented plugging and control production structure and the segmented plugging and control production method can balance the liquid supply profile of different well sections in the same branch and different branches, uniformly displace, realize accurate and active water control, maximize the remaining oil in the well area, effectively reduce the water cut rise rate and delay the production decline, and greatly improve the development effect of the oil field.

[0096] It can be understood that the above embodiments only express the preferred embodiments of the application, the description is more specific and detailed, but it cannot be understood as a limitation on the scope of the patent of the application; it should be pointed out that for ordinary skilled persons in the art, the above technical features can be freely combined without departing from the concept of the application, and some deformations and improvements can be made, which belong to the protection scope of the application; therefore, any equivalent transformation and modification within the scope of the claims of the application shall belong to the scope of the claims of the application.

Claims

1. A segmented blocking and control mining structure, characterized in that, It includes several branch wellbores, namely, a first branch wellbore, a second branch wellbore, ..., an nth branch wellbore; the segmented plugging and control production structure also includes a rotation production device, which includes tubing, a filter protection pipe and several packer components; The tubing is used to be inserted into the nth branch wellbore, and the filter protection tube is sleeved on the outer periphery of the tubing; the packer assembly is installed on the outer periphery of the tubing to divide the several branch wellbores into multiple production chambers, and the portion of the tubing located in each of the production chambers is provided with at least one sliding sleeve, and the production chamber and the branch wellbore opposite it are connected. The segmented plugging and control production structure includes a segmented production control mode and a segmented plugging and control mode. When the segmented plugging and control production structure is in the segmented production control mode, the sliding sleeve in any production chamber is opened; when the segmented plugging and control production structure is in the segmented plugging and control mode, the sliding sleeve in any production chamber with high water content is closed, or the sliding sleeve in any production chamber with high water content is opened while the sliding sleeves in other production chambers with non-high water content are closed. The oil pipe is injected with water-blocking agent, which is then injected into the water-producing formation through the sliding sleeve in the production chamber with high water content to seal it.

2. The segmented blocking and control mining structure according to claim 1, characterized in that, The value of n is a natural number less than or equal to 10.

3. The segmented blocking and control mining structure according to claim 1, characterized in that, The segmented plugging and control structure also includes a main branch wellbore, which is connected and interconnected with the nth branch wellbore; the main branch wellbore is provided with a casing shoe and a casing; at least one of the packer components is provided inside the casing.

4. The segmented blocking and control mining structure according to claim 1, characterized in that, Each of the packer assemblies includes an external packer and an internal packer; The filter protection tube includes multiple filter protection tube segments, and each filter protection tube segment is connected to two adjacent external packers at both ends. The in-tube packer is installed at intervals along the axial direction of the tubing on the tubing; at least a portion of the external packer blocks the annular space between the in-tube packer and the inner wall of the casing, and / or, at least a portion of the external packer blocks the annular space between the in-tube packer and at least a portion of the branch wellbore wall.

5. The segmented blocking and control mining structure according to claim 4, characterized in that, The sliding sleeve includes an intelligent electrically controlled sliding sleeve, and the segmented blocking and control structure also includes a control cable that passes through the external packer to connect with the sliding sleeve.

6. The segmented blocking and control mining structure according to claim 4, characterized in that, The external packer is a liquid-swellable packer.

7. The segmented blocking and control mining structure according to claim 4, characterized in that, The packer inside the tube is a liquid-swellable packer.

8. The segmented blocking and control mining structure according to claim 1, characterized in that, The end of the oil pipe is equipped with a plug.

9. A segmented blocking and control sampling method, applied to the segmented blocking and control sampling structure described in any one of claims 1 to 8, characterized in that, The segmented blocking and control sampling method includes the following steps: S10. Execute the segmented controlled mining mode, and sequentially open the sliding sleeves of the production compartment to perform segmented controlled mining; S20. Execute the segmented blocking mode, close the sliding sleeve in any production chamber with high water content, or open the sliding sleeve in any production chamber with high water content and close the sliding sleeves in other production chambers with non-high water content, inject water plugging agent from the oil pipe and inject it into the water-producing formation through the sliding sleeve in the production chamber with high water content to block it.

10. The segmented blocking and control sampling method according to claim 9, characterized in that, In step S20, the water content of the oil produced in the production tank is obtained, and it is determined whether the water content is high. If the water content is high, the sliding sleeve in the production tank corresponding to the high water content is closed, or the sliding sleeve in the production tank with high water content is opened, and the sliding sleeves in other production tanks with non-high water content are closed. Water plugging agent is injected from the oil pipe and injected into the water-producing formation through the sliding sleeve in the production tank with high water content to seal it.

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