A device and method for improving inter-stage uniform liquid production after staged fracturing of a horizontal well

Abstract

The application discloses a device and method for improving inter-stage uniform liquid production after segmented fracturing of horizontal wells, and belongs to the technical field of hydraulic fracturing in oil and gas field development. The device comprises a cylindrical main body, the surface of the cylindrical main body is distributed with holes with adjustable diameters, springs, rubber tubes and slips are symmetrically arranged at two ends in sequence, and the springs and the rubber tubes are sleeved on the cylindrical main body. In use, firstly, the equivalent diameter of the perforation hole after fracturing erosion is estimated, the reservoir pressure difference between adjacent fracturing stages and the diameter of the hole required at the position with relatively high pressure are calculated; the device is put into the horizontal well cylinder stage to be optimized, the hole is overlapped with the horizontal well perforation position, the slip is unlocked, the spring is elongated, the rubber tube is expanded to seal the space between the device and the horizontal well cylinder; the diameter of the hole is adjusted to the reference value, finally, the wellhead production is tested and the equivalent diameter of the hole is adjusted until the production is increased. The method can solve the problem of uneven liquid production distribution between the segmented fracturing stages of the horizontal well or even no production in some fracturing stages.

Description

Technical Field

[0001] This invention belongs to the field of hydraulic fracturing technology in oil and gas field development, specifically relating to a device and method for improving the uniform fluid production between stages after fracturing in horizontal wells. Background Technology

[0002] With the development of unconventional reservoirs such as tight oil and gas and shale oil and gas, the importance of horizontal well staged fracturing technology in oil and gas development is becoming increasingly prominent. Horizontal well staged fracturing technology uses packers such as bridge plugs to seal and divide a horizontal wellbore several kilometers long into multiple smaller sections. Within each section, perforations are performed at selected locations to connect the wellbore to the formation. High-pressure fluid is then pumped from the wellhead, flowing into the formation through the perforations. When the pressure exceeds the formation fracturing pressure, fractures form, and subsequent pumping of high-pressure fluid promotes the continued extension and propagation of these fractures.

[0003] Currently, the average length of the horizontal section in a horizontal well is 2000–3000 m, with longer horizontal wells reaching over 5000 m. Each section is fractured every 50–150 m, with 3–5 perforation clusters, or even 8–10 clusters, resulting in hundreds of perforation clusters in a single well. If the fractures at each perforation cluster successfully propagate, a single well can form hundreds of fractures. However, within the 2000–3000 m range of the horizontal wellbore, the reservoir heterogeneity is usually strong, and the formation pressure varies between fractured sections, leading to differences in the fluid flow patterns within each fracture. Studies using fiber optic testing technology have repeatedly found that regardless of whether a single section has 3–5 or 8–10 perforation clusters, the vast majority of perforation clusters can successfully inject fluid. Although the fluid injection intensity varies among each cluster, it can still be inferred that each fractured section produces fractures, resulting in dozens to hundreds of fractures near the wellbore. For tight gas and shale oil and gas reservoirs with significant heterogeneity, as the number of fracturing stages and perforation clusters in a single well increases, the distribution of fluid production between fracturing stages becomes highly uneven, and some fracturing stages even produce no fluid. This not only reduces the flowback rate of fracturing fluid but also exacerbates reservoir damage, reduces oil and gas production, and results in economic waste. Analysis suggests that during the production stage of an oil and gas well, the horizontal wellbore is a pressure-connected system. Part of the reason for fracture "failure" lies in the stress interference between fracturing stages. Areas with higher formation pressure are more likely to experience fluid outflow and increase wellbore pressure. When the wellbore pressure exceeds the reservoir pressure in low-pressure areas, it leads to fracture "failure" in the low-pressure areas. Furthermore, the smaller the orifice diameter, the greater the throttling pressure differential that fluid flow needs to overcome (Equation 1). The post-fracturing orifice diameter can be measured using a downhole camera.

[0004]

[0005] In the formula, Δp is the orifice throttling pressure difference required in the high-pressure area; q is the flow rate; ρ l Where n is the fluid viscosity; n is the number of orifices; D is the orifice diameter; CD is the flow coefficient of the orifice.

[0006] Therefore, it is necessary to rely on technological means to maximize the role of each fracture, increase oil and gas production, and improve economic benefits. Summary of the Invention

[0007] In order to overcome the shortcomings of the prior art, the present invention aims to provide an apparatus and method for improving the uniformity of fluid production between fracturing stages in horizontal wells, and to solve the problem of uneven fluid production distribution between fracturing stages in horizontal wells.

[0008] To achieve the above objectives, the present invention employs the following technical solution:

[0009] This invention discloses a device for improving the uniformity of fluid production between stages after fracturing in horizontal wells. The device includes a cylindrical body with several adjustable-diameter orifices distributed on its surface. A spring, a rubber sleeve, and slips are symmetrically arranged at both ends of the cylindrical body. The slips are fixed to both ends of the cylindrical body. The spring and the rubber sleeve are both sleeved on the cylindrical body. The end of the spring away from the rubber sleeve is fixed to the outer wall of the cylindrical body and remains stationary, and is in a compressed state before the slips are unlocked. The rubber sleeve is an expandable rubber sleeve that can slide on the outer wall of the cylindrical body after the slips are unlocked.

[0010] Preferably, the surface of the eyelet is provided with an adjusting shim, which consists of symmetrical shims A and B. Shims A and B are hollow structures with a semi-circle cut out in the center. Shims A and B can adjust the diameter of the eyelet through relative movement.

[0011] More preferably, both gasket A and gasket B have an embedded integrated circuit chip inside, and gasket A and gasket B are symmetrically arranged on the surface of the hole via a slide rail.

[0012] Preferably, the position of the orifice coincides with the position of the horizontal well perforation.

[0013] Preferably, the outer diameter of the cylindrical body is 1-5 mm smaller than the inner diameter of the horizontal wellbore, and the length of the cylindrical body is 10-100 m.

[0014] Preferably, the slip is a cylindrical structure with a wall thickness of 1-2 cm. The outer diameter of the slip is the same as the outer diameter of the cylindrical body. Slip pieces are distributed circumferentially on the outer side of the slip. The slip is unlocked after being subjected to vibration or energy shock, and the slip pieces unfold to the side to bite the inner wall of the horizontal well barrel.

[0015] Preferably, the rubber sleeve is filled with a slow-release agent, which can react to generate gas in an environment of 80℃~150℃, causing the rubber sleeve to expand and adhere tightly to the inner wall of the horizontal wellbore.

[0016] The present invention also discloses a method for producing fluid from the above-mentioned device for improving the uniformity of fluid production between sections after fracturing in horizontal wells, the steps of which are as follows:

[0017] 1) Based on the law of perforation erosion caused by displacement, fluid volume or sand volume, estimate the equivalent diameter of the perforated hole after fracturing erosion, and calculate the average throttling pressure difference of the fluid flowing from the formation to the horizontal wellbore through the perforated hole.

[0018] 2) Calculate the reservoir pressure difference between adjacent fractured sections by combining the methods for evaluating formation pressure;

[0019] 3) Calculate the required perforation throttling pressure difference for the high-pressure zone based on the average throttling pressure difference of the fluid flowing from the formation to the horizontal wellbore through the perforation orifice and the reservoir pressure difference between adjacent fractured sections; calculate the required orifice diameter for the relatively high pressure position between adjacent fractured sections based on the required perforation throttling pressure difference for the high-pressure zone.

[0020] 4) Deploy the device to the horizontal wellbore section to be optimized, aligning the device's orifice with the horizontal well perforation position, unlock the slips, and secure the device.

[0021] 5) The rubber sleeve expands downhole; under the action of the slip tension, the spring extends and compresses the rubber sleeve, creating an annular space between the rubber sleeve sealing device and the horizontal wellbore;

[0022] 6) Adjust the diameter of the orifice to the orifice diameter required for the position with relatively high pressure between adjacent fracturing sections calculated in step 3);

[0023] 7) Test the wellhead production and continue to adjust the diameter of the orifice in step 6) until the production increases.

[0024] Preferably, in step 2), the method for evaluating formation pressure includes the results of downhole pressure gauge readings, wellhead pump shutdown pressure after each fracturing operation, or formation pressure tests of adjacent vertical wells around the fracturing section.

[0025] Preferably, the formula for calculating the required orifice diameter at the location with relatively higher pressure between adjacent fracturing sections is as follows:

[0026]

[0027] Where Δp is the required orifice throttling pressure difference in the high-pressure region, d2 is the required orifice diameter at the relatively high pressure position between adjacent fracturing sections, q is the flow rate, and ρ is the pressure difference. l Where n is the fluid viscosity, n is the number of orifices, D is the orifice diameter, and C is the fluid viscosity. D is the flow coefficient of the orifice.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] This invention provides a device for improving the uniformity of fluid production between stages after fracturing in horizontal wells. The device features an adjustable-diameter orifice on a cylindrical body, allowing for adjustment of flow rate and pressure differential. An expandable rubber sleeve, combined with a coordinated design of slips, springs, and the sleeve, ensures that as the slips are released, the compressed spring extends, pushing and compressing the sleeve. The sleeve further seals the annular structure formed between the cylindrical body and the horizontal wellbore, achieving inter-stage pressure isolation. Furthermore, this device is a full-bore structure, not interfering with other operations. By sealing the cylindrical body and horizontal wellbore through sleeve expansion and the coordinated action of slips, springs, and the sleeve, combined with the adjustable-diameter orifice, the pressure within the horizontal wellbore is reduced, increasing the probability of fluid successfully flowing out of the relatively low-pressure fractures. This effectively solves the problem of uneven fluid production distribution between stages in horizontal well fracturing.

[0030] This invention provides a method for improving the uniformity of fluid production between sections after fracturing in horizontal wells. It employs the working principle of integrated limiting perforation and downhole chokes, utilizing the fundamental principle that smaller perforation diameters result in greater choke pressure differentials. By reducing the diameter of the perforation at the outlet of the relatively high-pressure fracture, the choke pressure differential is increased, thereby reducing the pressure in the horizontal wellbore and increasing the probability of fluid successfully flowing out of the relatively low-pressure fracture. This method meets the field requirements of highly heterogeneous tight gas and shale oil and gas reservoirs. The full-bore structure does not affect other operations, is simple to operate, and has low cost. It can solve the problems of uneven fluid production between sections after fracturing in horizontal wells and low single-well production. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the overall structure of the device for improving the uniformity of liquid production between stages according to the present invention;

[0032] Figure 2 This is a schematic diagram of the structure of the adjusting shim of the present invention.

[0033] Wherein: 1-Upper clamp; 2-Upper rubber sleeve; 3-Upper spring; 4-Cylindrical body; 5-Hole; 6-Lower spring; 7-Lower rubber sleeve; 8-Lower clamp; 9-Adjusting shim. Detailed Implementation

[0034] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0035] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus. The term "horizontal wellbore" in this invention is equivalent to "casing" in the petroleum industry.

[0036] The present invention will now be described in further detail with reference to the accompanying drawings:

[0037] The present invention provides a device for improving the uniform fluid production between stages after fracturing in a horizontal well. The device includes a cylindrical body 4. Springs, rubber sleeves and slips are symmetrically arranged at both ends of the cylindrical body 4. The slips are fixed at both ends of the cylindrical body 4. The springs and rubber sleeves are both sleeved on the cylindrical body 4. The end of the spring away from the rubber sleeve is fixed to the outer wall of the cylindrical body 4 and remains stationary. It is in a compressed state before the slips are unlocked. After the slips are unlocked, the rubber sleeve can slide on the outer wall of the cylindrical body 4.

[0038] The cylindrical body 4 is a full-bore structure, with an outer diameter 1-5 mm smaller than the inner diameter of the horizontal wellbore, and a length of 10-100 m. Multiple holes 5 are spirally distributed on the surface of the cylindrical body 4. The hole density and azimuth design of the holes 5 are consistent with the perforation scheme of the horizontal wellbore, with a hole diameter of 5-10 cm. Each hole 5 is fitted with an adjustable shim 9, consisting of shim A and shim B. Shims A and B are hollow structures with a semi-circular center cut out, and an integrated circuit chip composed of transistors is embedded inside. Shims A and B are symmetrically arranged on the surface of the hole 5 via slide rails. In use, by controlling the relative movement of shims A and B, the outlet diameter of the fluid flowing from the slot to the horizontal wellbore is changed.

[0039] The slips are used to connect the horizontal shaft and tension the spring. The slips on both sides of the cylindrical body 4 are the upper slip 1 and the lower slip 8, respectively. Both the upper slip 1 and the lower slip 8 are cylindrical structures with a wall thickness of 1-2 cm and an outer diameter slightly smaller than the inner diameter of the horizontal shaft by 1-5 mm. There are 6 slip pieces distributed circumferentially on the outer side of the slips. When the slips are subjected to vibration or energy shock, they unlock, and the slip pieces unfold to the side, biting into the inner wall of the horizontal shaft, thereby fixing the position of this device in the horizontal shaft.

[0040] The rubber sleeves are used to seal the annular space formed between the horizontal wellbore and the device, isolating adjacent fracturing sections. The rubber sleeves on both sides of the cylindrical body 4 are the upper rubber sleeve 2 and the lower rubber sleeve 7, respectively. Both the upper rubber sleeve 2 and the lower rubber sleeve 7 are strip-shaped rubber sleeves, surrounding the outer wall of the cylindrical body 4. The interior of both the upper rubber sleeve 2 and the lower rubber sleeve 7 contains an appropriate amount of granular or powdered chemical slow-release agent. This chemical slow-release agent can react to generate gas in a high-temperature environment of 80℃~150℃ downhole, causing the upper rubber sleeve 2 and the lower rubber sleeve 7 to expand and adhere tightly to the inner wall of the horizontal wellbore, thereby achieving isolation between the perforated sections. The chemical slow-release agent is preferably a potassium permanganate or ammonium salt-based slow-release agent.

[0041] Springs are used to compress the rubber tube. The springs on both sides of the cylindrical body 4 are divided into an upper spring 3 and a lower spring 6, both of which surround the outer wall of the cylindrical body 4. After the slips are released, the compressed springs extend as the slips unfold to the side. The extended springs push the rubber tube towards one side of the slips until the rubber tube is compressed, causing it to extend laterally and thus improving the sealing effect.

[0042] This invention provides a method for improving the uniform fluid production between sections after fracturing in horizontal wells, comprising the following steps:

[0043] (1) Based on the pattern of perforation erosion obtained from downhole cameras or previous data on displacement / fluid / sand volume, estimate the equivalent diameter d1 of the perforated hole after fracturing erosion, and calculate the average throttling pressure difference Δp1 of the fluid flowing from the formation to the horizontal wellbore through the perforated hole according to the following formula.

[0044]

[0045] (2) Calculate the reservoir pressure difference Δp between adjacent fractured sections using effective methods for evaluating formation pressure, such as downhole pressure gauge readings, wellhead pump shutdown pressure after each fracturing operation, or formation pressure test results from adjacent vertical wells around the fractured section. s ;

[0046] (3) In order to overcome pressure interference between sections and achieve uniform fluid production in fracturing sections of adjacent wells, the outlet pressure of the high-pressure zone after overcoming the reservoir pressure difference and the orifice throttling pressure difference should be as close as possible to that of the low-pressure zone. The orifice throttling pressure difference Δp required for the high-pressure zone is calculated according to the following formula:

[0047] Δp=Δp s +Δp1 (3)

[0049] In the formula, Δp s Δp is the reservoir pressure difference between adjacent fracturing sections; Δp is the required orifice throttling pressure difference in the high-pressure region.

[0050] Then, calculate the required orifice diameter d2 for the location with relatively higher pressure between adjacent fracturing sections using the following formula:

[0051]

[0052] (4) Deploy the above device and position it in the horizontal well section to be optimized, so that the hole 5 on the device coincides with the perforation position of the horizontal well. Use vibration, ignition or rapid throwing to unlock the slips, unfold to the side and bite the inner wall of the horizontal well, and fix the position of the device.

[0053] (5) Under the action of the valve tension, the spring extends and compresses the rubber tube to make it stick to the inner wall of the horizontal wellbore; the slow-release agent in the rubber tube undergoes a chemical reaction to produce gas in the high temperature environment, the rubber tube expands, and completely seals the annular space between the device and the horizontal wellbore, thereby achieving the effect of sealing the adjacent perforation cluster / section (among which, the expansion of the rubber tube and the compression of the rubber tube are not sequential, and the two methods work together to improve the sealing effect).

[0054] (6) Use remote control or other means to control the relative movement of gasket A and gasket B, and adjust the diameter of fluid outlet orifice 5 from its original state to the reference value d2 calculated in step (3);

[0055] (7) Based on the production / gas profile test or wellhead production, continue to finely adjust the diameter of the outlet orifice 5 in step (6) until the outlet pressure difference between the two fracturing sections is optimized to the minimum, thereby increasing production.

[0056] Example 1

[0057] like Figure 1 and Figure 2As shown, a device for improving the uniformity of fluid production between stages after fracturing in a horizontal well comprises, in sequence along the horizontal direction, an upper slip 1, an upper rubber sleeve 2, an upper spring 3, a cylindrical body 4, a lower spring 6, a lower rubber sleeve 7, and a lower slip 8. Both the upper slip 1 and the lower slip 8 are cylindrical structures and are fixed to both ends of the cylindrical body 4. The wall thickness of the upper slip 1 and the lower slip 8 is 1–2 cm, and their outer diameter is slightly smaller than the inner diameter of the horizontal wellbore by 1–5 mm. Six slip pieces are circumferentially distributed on the outer side of both the upper slip 1 and the lower slip 8. Upon vibration or energy impact, the upper slip 1 and the lower slip 8 unlock, and the slip pieces unfold laterally, engaging the inner wall of the horizontal wellbore, thereby fixing the device in position within the horizontal wellbore. Both the upper rubber sleeve 2 and the lower rubber sleeve 7 are strip-shaped rubber sleeves that wrap around the outer wall of the cylindrical body 4. After the upper slip 1 and the lower slip 8 are unlocked, the upper rubber sleeve 2 and the lower rubber sleeve 7 can slide on the outer wall of the cylindrical body 4. The upper rubber sleeve 2 and the lower rubber sleeve 7 are each filled with an appropriate amount of potassium permanganate, which can react to generate gas in the high-temperature environment downhole, causing the upper rubber sleeve 2 and the lower rubber sleeve 7 to expand and stick tightly to the inner wall of the horizontal wellbore, thereby achieving the sealing between the perforated sections. The upper spring 3 and the lower spring 6 wrap around the outer wall of the cylindrical body 4, and the end away from the rubber sleeve is fixed to the outer wall of the cylindrical body 4 and does not move. The upper spring 3 and the lower spring 6 are initially (i.e., the slips) Before unlocking, the cylinder is in a compressed state; the main body 4 of the cylinder is a full-bore structure, with an outer diameter 1-5 mm smaller than the inner diameter of the horizontal wellbore, and a length of 10-100 m; multiple holes 5 with a diameter of 5-10 cm are spirally distributed on the surface of the cylinder, and the hole density / azimuth design of the holes 5 is consistent with the perforation scheme of the horizontal wellbore; each hole 5 is equipped with an adjusting shim 9, which consists of symmetrical A shims and B shims. The A shims and B shims are hollow structures with a semi-circle cut out in the center, and an integrated circuit chip composed of transistors is embedded inside the shims. The A shims and B shims are symmetrically arranged on the surface of the hole 5 via slide rails. In use, the integrated circuit chips embedded inside the A shims and B shims receive pulse signals transmitted by the ground controller and decode them. The relative movement of the A shims and B shims is controlled by remote control, thereby changing the outlet diameter of the fluid flowing out of the slot into the horizontal wellbore.

[0058] A method for improving the uniformity of fluid production between stages after fracturing in horizontal wells includes the following steps:

[0059] (1) Based on downhole camera technology, observe the diameter change of the perforated hole after erosion during the fracturing operation, estimate the equivalent diameter d1 of the perforated hole after fracturing erosion, and determine the flow coefficient C. D The number of perforations, n;

[0060] The average throttling pressure difference Δp1 of the fluid flowing from the formation through the perforation orifice into the horizontal wellbore is calculated using the following formula;

[0061]

[0062] (2) Estimate the formation pressure at the location of each fractured section using the formation pressure test results of adjacent vertical wells around each fractured section, select two adjacent fractured sections with large pressure differences as optimization targets, and calculate the reservoir pressure difference Δp between adjacent fractured sections. s ;

[0063] (3) In order to overcome pressure interference between sections and achieve uniform fluid production in adjacent well fracturing sections, the outlet pressure of the high-pressure zone after overcoming the reservoir pressure difference and the orifice throttling pressure difference should be as close as possible to that of the low-pressure zone. The orifice throttling pressure difference Δp required in the high-pressure zone is calculated according to the following formula:

[0064] Δp=Δp s +Δp1 (3)

[0066] In the formula, Δp s Δp is the reservoir pressure difference between adjacent fracturing sections; Δp is the required orifice throttling pressure difference in the high-pressure region.

[0067] Then, calculate the required orifice diameter d2 for the location with relatively higher pressure between adjacent fracturing sections using the following formula:

[0068]

[0069] (4) Place the device of the present invention between the two fracturing sections that are the optimization targets in step (2). During installation, ensure that the hole 5 on the device coincides with the perforation position of the horizontal well. Use vibration to unlock the upper slip 1 and the lower slip 8, and unfold to the side to bite the inner wall of the horizontal well barrel to fix the device position.

[0070] (5) Under the pull of the upper slip 1 and the lower slip 8 respectively, the upper spring 3 and the lower spring 6 extend and compress the upper rubber cylinder 2 and the lower rubber cylinder 7 respectively, so that the upper rubber cylinder 2 and the lower rubber cylinder 7 deform radially and stick to the inner wall of the horizontal wellbore; the potassium permanganate in the upper rubber cylinder 2 and the lower rubber cylinder 7 undergoes a chemical reaction to produce gas in the high temperature environment at the bottom of the well. After the upper rubber cylinder 2 and the lower rubber cylinder 7 expand, they completely seal the annular space between the device and the horizontal wellbore, thereby achieving the effect of sealing the two fracturing sections;

[0071] (6) The relative movement of gasket A and gasket B is controlled by remote control, and the diameter of the fluid outlet orifice is reduced to d2. After the orifice diameter is reduced, the production of the horizontal well changes accordingly. Based on the change of wellhead production q, the diameter of the outlet orifice is finely adjusted again using formula (2) to further reduce the outlet pressure difference between the two fracturing sections. When the outlet pressure difference is optimized to the minimum, the production of the horizontal well is optimized.

[0072] The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made to the technical solution based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.

Claims

1. A device for improving the uniformity of fluid production between stages after fracturing in a horizontal well, characterized in that, It includes a cylindrical body (4), and the surface of the cylindrical body (4) has several holes (5) with adjustable diameters. Springs, rubber tubes and clips are symmetrically arranged at both ends of the cylindrical body (4). The clips are fixed at both ends of the cylindrical body (4). The springs and rubber tubes are both sleeved on the cylindrical body (4). The end of the spring away from the rubber tube is fixed to the outer wall of the cylindrical body (4) and remains stationary. It is in a compressed state before the clips are unlocked. The rubber tube is an expandable rubber tube. After the clips are unlocked, the rubber tube can slide on the outer wall of the cylindrical body (4).

2. The device for improving the uniformity of fluid production between stages after fracturing in a horizontal well according to claim 1, characterized in that, An adjusting shim (9) is provided on the surface of the eyelet (5). The adjusting shim (9) is composed of symmetrical shims A and B. The shims A and B are hollow structures with a semi-circle cut out in the center. The shims A and B can adjust the diameter of the eyelet (5) by relative movement.

3. The device for improving the uniformity of fluid production between stages after fracturing in a horizontal well according to claim 2, characterized in that, Both gasket A and gasket B contain embedded integrated circuit chips. Gasket A and gasket B are symmetrically arranged on the surface of the eyelet (5) via a slide rail.

4. The device for improving the uniformity of fluid production between stages after fracturing in a horizontal well according to claim 1, characterized in that, The position of the perforation (5) is consistent with the position of the horizontal well perforation.

5. The apparatus for improving the uniformity of fluid production between stages after fracturing in a horizontal well according to any one of claims 1 to 4, characterized in that, The outer diameter of the cylindrical body (4) is 1-5 mm smaller than the inner diameter of the horizontal wellbore, and the length of the cylindrical body (4) is 10-100 m.

6. The apparatus for improving the uniformity of fluid production between stages after fracturing in a horizontal well according to any one of claims 1 to 4, characterized in that, The slip is a cylindrical structure with a wall thickness of 1-2 cm. The outer diameter of the slip is consistent with the outer diameter of the cylindrical body (4). Slip pieces are distributed circumferentially on the outer side of the slip. The slip is unlocked after being subjected to vibration or energy shock, and the slip pieces unfold to the side and bite into the inner wall of the horizontal well barrel.

7. The apparatus for improving the uniformity of fluid production between stages after fracturing in a horizontal well according to any one of claims 1 to 4, characterized in that, The rubber sleeve contains a slow-release agent, which can react to generate gas in an environment of 80℃~150℃, causing the rubber sleeve to expand and adhere tightly to the inner wall of the horizontal wellbore.

8. A method for producing fluid based on the apparatus for improving uniform fluid production between sections after fracturing in a horizontal well, according to any one of claims 1 to 7, characterized in that, The steps are as follows: 1) Based on the law of perforation erosion caused by displacement, fluid volume or sand volume, estimate the equivalent diameter of the perforated hole after fracturing erosion, and calculate the average throttling pressure difference of the fluid flowing from the formation to the horizontal wellbore through the perforated hole. 2) Calculate the reservoir pressure difference between adjacent fractured sections by combining the methods for evaluating formation pressure; 3) Calculate the required perforation throttling pressure difference for the high-pressure zone based on the average throttling pressure difference of the fluid flowing from the formation to the horizontal wellbore through the perforation orifice and the reservoir pressure difference between adjacent fractured sections; calculate the required orifice diameter for the relatively high pressure position between adjacent fractured sections based on the required perforation throttling pressure difference for the high-pressure zone. 4) Deploy the device to the horizontal well section to be optimized, so that the hole (5) of the device coincides with the perforation position of the horizontal well, unlock the slips, and fix the device; 5) The rubber sleeve expands downhole; under the action of the slip tension, the spring extends and compresses the rubber sleeve, creating an annular space between the rubber sleeve sealing device and the horizontal wellbore; 6) Adjust the diameter of the orifice (5) to the orifice diameter required for the position with relatively high pressure between adjacent fracturing sections calculated in step 3); 7) Test the wellhead production and continue to adjust the diameter of the orifice (5) in step 6) until the production increases.

9. The method according to claim 8, characterized in that, In step 2), the methods for evaluating formation pressure include the results of downhole pressure gauge readings, wellhead pump shutdown pressure after each fracturing operation, or formation pressure tests of adjacent vertical wells around the fracturing section.

10. The method according to claim 8, characterized in that, In step 3), the formula for calculating the required orifice diameter at the location with relatively higher pressure between adjacent fracturing sections is: Where Δp is the required orifice throttling pressure difference in the high-pressure region, d2 is the required orifice diameter at the relatively high pressure position between adjacent fracturing sections, q is the flow rate, and ρ is the pressure difference. l Where n is the fluid viscosity, n is the number of orifices, D is the orifice diameter, and C is the fluid viscosity. D is the flow coefficient of the orifice.

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