Single-flow acid pressure-controlled flow profile integrated device and completion pipe column

Abstract

The application provides a single-flow acid pressure-controlled flow profile control integrated device and a well completion string, and belongs to the technical field of oil and gas well completion and yield increase. The well completion string comprises at least one ball-throwing type single-flow acid pressure-controlled flow profile control integrated device and a differential pressure type single-flow acid pressure-controlled flow profile control integrated device arranged at the lower end of the ball-throwing type single-flow acid pressure-controlled flow profile control integrated device. The outer cylinder wall of the ball-throwing type single-flow acid pressure-controlled flow profile control integrated device and the differential pressure type single-flow acid pressure-controlled flow profile control integrated device is provided with a flow control profile control device and a large-displacement one-way acid pressure valve, so that the well completion string can simultaneously realize the two functions of segmented acid pressure and later adjustment of the liquid production profile, the oil and gas production of a single well can be increased, the whole oil well life profile control and water control can be realized, the low water cut oil production period and the gas production period can be prolonged, and the oil well yield increase and efficiency increase are facilitated.

Description

Technical Field

[0001] This invention belongs to the field of oil and gas well completion and production enhancement technology, specifically relating to an integrated device for single-flow acid pressure control and profile adjustment, and a completion string. Background Technology

[0002] Currently, for oil and gas reservoirs with poor reservoir properties or low pressure and low permeability, staged acid fracturing or staged acidizing of long horizontal wells is often used to enhance production. Generally speaking, most of the oil and gas fields developed in China have entered the middle and late stages. Blocks with good reservoir properties have basically been developed. The remaining areas that can be developed generally require acid fracturing or staged acid fracturing to achieve commercial production. As the development of old oil fields enters the middle and late stages and the formation energy is depleted, edge and bottom water gradually invades. Some newly drilled wells face the problem of rapid high water cut after production. Therefore, adjusting the production profile, controlling the water production rate, and extending the low water cut oil production period and low water cut gas production period have become urgent needs for the efficient development of oil and gas reservoirs in the middle and late stages of development. Currently, staged acid fracturing is mainly achieved by using multi-stage acid fracturing sliding sleeves + staged packers. Adjusting the production profile usually requires staged operation and the installation of separate production profile adjustment tools, or the installation of separate injection tools to inject profile-adjusting plugging agents. Currently, conventional acid fracturing wells do not have the function of adjusting the production profile. Furthermore, for horizontal wells with multi-stage acid fracturing sleeves, only the opening of the sleeve serves as the channel connecting the wellbore to the reservoir, resulting in a limited number of points for injecting chemical agents into the reservoir. This limits the ability to accurately adjust the profile and shut off water to control formation water production.

[0003] Given that wells in the periphery or infill wells of mid-to-late stage oil and gas reservoirs currently require acid fracturing to increase oil and gas production, and that wells in mid-to-late stage oil and gas reservoirs face the risk of rapid high water cut or violent water flooding after acid fracturing, the need for acid fracturing and production profile control in newly constructed oil and gas wells in mid-to-late stage development is urgent. Considering that acid fracturing tubing cannot mechanically adjust the production profile for water control, and the limitations of using chemical agents for profile adjustment and water shut-off in acid fracturing tubing, designing a tool system that can simultaneously achieve segmented acid fracturing and subsequent production profile adjustment based on a single well completion tubing run is a problem that urgently needs to be solved. Summary of the Invention

[0004] The purpose of this invention is to solve the problems existing in the prior art and provide an integrated device for single-flow acid fracturing, flow control and profile adjustment, as well as a completion string, which can achieve the functions of segmented acid fracturing and adjusting the production fluid profile to control water through a single process string operation.

[0005] One objective of this invention is to provide a ball-throwing type single-flow acid pressure control and profile adjustment integrated device.

[0006] The second objective of this invention is to provide an integrated device for differential pressure single-flow acid pressure control and profile regulation.

[0007] The third objective of this invention is to provide a well completion string.

[0008] This invention is achieved through the following technical solution:

[0009] In a first aspect, the present invention provides a ball-throwing type single-flow acid pressure control and profile adjustment integrated device, comprising an outer cylinder, wherein an upper connecting joint, an outer sliding sleeve and a lower connecting joint are sequentially connected from top to bottom inside the outer cylinder, an inner sliding sleeve is provided inside the outer sliding sleeve, and a ball seat is provided at the bottom of the inner sliding sleeve;

[0010] The outer cylinder wall is equipped with a flow control and profile adjustment device and a large-capacity one-way acid pressure valve.

[0011] A further improvement of the present invention is that:

[0012] The flow control and profile adjustment device includes a device body. The device body is provided with an inlet, an inflow channel and a flow control and profile adjustment oil-gas mixture diversion channel connected sequentially from one end face to the other end face. The inlet is located on one side of the inner wall of the outer cylinder, and the flow control and profile adjustment oil-gas mixture diversion channel is located on the outer side of the outer cylinder.

[0013] A further improvement of the present invention is that:

[0014] The large-capacity one-way acid pressure valve includes a valve body, on which an acid pressure injection port and an acid pressure outlet are provided in communication with each other. An acid pressure shut-off plate is provided on the end face of the valve body located at one end of the acid pressure outlet. A spring is connected to the inner side of the acid pressure shut-off plate, and the other end of the spring is fixed to the inner wall of the acid pressure outlet.

[0015] The acid injection port is located on one side of the inner wall of the outer cylinder, and the acid outlet is located on one side of the outer wall of the outer cylinder.

[0016] A further improvement of the present invention is that:

[0017] The upper part of the outer cylinder is provided with an upper connector, which is connected to the upper connecting connector through an upper connector male threaded connector, and an upper connector sealing ring is provided between the upper connector and the inner wall of the outer cylinder;

[0018] The lower part of the outer cylinder is provided with a lower connector, which is connected to the lower connecting connector through a lower connector male threaded connector, and a lower connector sealing ring is provided between the lower connector and the inner wall of the outer cylinder.

[0019] A further improvement of the present invention is that:

[0020] The upper connecting joint, the outer sliding sleeve, and the lower connecting joint have a certain gap with the outer cylinder to form an internal flow cavity;

[0021] The outer sliding sleeve is provided with an acid pressure injection hole, and the inner sliding sleeve is disposed inside the outer sliding sleeve and fixedly connected by a pin. The inner sliding sleeve blocks the acid pressure injection hole.

[0022] In a second aspect, the present invention provides a differential pressure type single-flow acid pressure control and profile adjustment integrated device, comprising an outer cylinder, wherein an upper connector, an outer sliding sleeve and a lower connector are arranged sequentially from the upper right to the lower inside the outer cylinder, and an inner sliding sleeve is arranged inside the outer sliding sleeve, wherein the upper part of the inner sliding sleeve has a large cross-section and the lower part has a small cross-section.

[0023] The outer cylinder wall is equipped with a flow control and profile adjustment device and a large-capacity one-way acid pressure valve.

[0024] A further improvement of the present invention is that:

[0025] The flow control and profile adjustment device includes a device body. The device body is provided with an inlet, an inflow channel and a flow control and profile adjustment oil-gas mixture diversion channel connected sequentially from one end face to the other end face. The inlet is located on one side of the inner wall of the outer cylinder, and the flow control and profile adjustment oil-gas mixture diversion channel is located on the outer side of the outer cylinder.

[0026] A further improvement of the present invention is that:

[0027] The large-capacity one-way acid pressure valve includes a valve body, on which an acid pressure injection port and an acid pressure outlet are provided in communication with each other. An acid pressure shut-off plate is provided on the end face of the valve body located at one end of the acid pressure outlet. A spring is connected to the inner side of the acid pressure shut-off plate, and the other end of the spring is fixed to the inner wall of the acid pressure outlet.

[0028] The acid injection port is located on one side of the inner wall of the outer cylinder, and the acid outlet is located on one side of the outer wall of the outer cylinder.

[0029] A further improvement of the present invention is that:

[0030] The upper part of the outer cylinder is provided with an upper connector, which is connected to the upper connecting connector through an upper connector male threaded connector, and an upper connector sealing ring is provided between the upper connector and the inner wall of the outer cylinder;

[0031] The lower part of the outer cylinder is provided with a lower connector, which is connected to the lower connecting connector through a lower connector male threaded connector, and a lower connector sealing ring is provided between the lower connector and the inner wall of the outer cylinder.

[0032] A further improvement of the present invention is that:

[0033] The upper connecting joint, the outer sliding sleeve, and the lower connecting joint have a certain gap with the outer cylinder to form an internal flow cavity;

[0034] The outer sliding sleeve is provided with an acid pressure injection hole, and the inner sliding sleeve is disposed inside the outer sliding sleeve and fixedly connected by a pin. The inner sliding sleeve blocks the acid pressure injection hole.

[0035] A third aspect of the present invention provides a well completion string, comprising at least one ball-drop type single-flow acid pressure control and profile control integrated device and a differential pressure type single-flow acid pressure control and profile control integrated device disposed at the lower end of the ball-drop type single-flow acid pressure control and profile control integrated device.

[0036] Compared with the prior art, the beneficial effects of the present invention are:

[0037] The completion string of this invention can meet the needs of wells or infill wells in oil and gas reservoirs with poor reservoir properties or in the middle and late stages of development. On the one hand, segmented acid fracturing is required to achieve commercial production. On the other hand, due to the rising waterline and complex oil-water relationship, it is necessary to consider the need to adjust the production profile after acid fracturing production, such as rapid high water cut or violent water flooding.

[0038] Given that conventional chemical injection for profile control and water shut-off is limited by the inner diameter of the segmented acid fracturing sleeve, resulting in inaccurate sealing and a relatively short effective period; and that conventional segmented acid fracturing tubing cannot be used to further control water and adjust the production profile, while mechanical water control tools typically achieve water control through special flow channels or mechanical structures, which result in relatively small flow channels due to their ability to identify different fluids and create a throttling effect, contradicting the principle of acid fracturing that requires a large amount of injection into the formation in a short time to create effective positive pressure and fracture the rock, this invention's completion tubing can simultaneously achieve both segmented acid fracturing and subsequent production profile adjustment functions. This can increase single-well oil and gas production, provide profile control and water management throughout the entire well lifecycle, extend the low water-cut oil and gas production period, and help increase oil well production and efficiency. Attached Figure Description

[0039] Figure 1 This is a structural diagram of a ball-throwing type single-flow acid pressure control and profile control integrated device;

[0040] Figure 2 This is a structural diagram of a differential pressure single-flow acid pressure control and profile control integrated device;

[0041] Figure 3 This is a structural diagram of the flow control and profile adjustment device;

[0042] Figure 4 This is a structural diagram of a large-capacity one-way acid pressure valve.

[0043] In the diagram, 1. Outer cylinder, 2. Upper connecting joint, 3. Outer sliding sleeve, 4. Lower connecting joint, 5. Inner sliding sleeve, 6. Ball seat, 7. Flow control and profile adjustment device, 7-1. Flow control and profile adjustment oil-gas-water mixture diversion channel, 7-2. Inlet channel, 7-3. Inlet, 8. Large displacement one-way acid pressure valve, 8-1. Acid pressure injection port, 8-2. Acid pressure shut-off plate, 8-3. Acid pressure outlet, 8-4. Spring, 9. Upper joint, 10. Upper joint male threaded connector, 11. Upper joint sealing ring, 12. Lower joint, 13. Lower joint male threaded connector, 14. Internal flow cavity, 15. Acid pressure injection hole, 16. Pin, 17. Large cross-section of inner sheath, 18. Small cross-section of inner sliding sleeve. Detailed Implementation

[0044] The present invention will now be described in further detail with reference to the accompanying drawings:

[0045] Currently, wells in poorly developed or late-stage oil and gas reservoirs, particularly those at the periphery or infill sites, require staged acid fracturing to achieve commercial production. For these reservoirs, especially those in the late stages, the rising waterline and complex oil-water relationships often present risks of rapid high water cut or sudden water flooding. This necessitates simultaneous consideration of acid fracturing and water control through production profile adjustments. Conventional chemical injection for profile control and water shut-off is limited by the inner diameter of the staged acid fracturing sleeve, resulting in inaccurate sealing and a relatively short effective period. Furthermore, conventional staged acid fracturing tubing cannot be used for staged water control and production profile adjustments. The tubing system, and mechanical water control tools, generally achieve water control through special flow channels or special mechanical structures. Because they have special flow channels or special structures that can identify different fluids and produce a throttling effect, the flow passage is generally relatively small. This contradicts the principle that acid fracturing requires a large amount of fluid to be injected into the formation in a short time to form effective positive pressure to fracture the rock. Therefore, it is necessary to design a tool system that can simultaneously achieve segmented acid fracturing and subsequent adjustment of the production profile based on a single well completion operation tubing. This system can achieve the functions of segmented acid fracturing and water control by adjusting the production profile through a single process tubing operation.

[0046]

Example 1

[0047] like Figure 1 As shown, this embodiment provides a ball-throwing type single-flow acid pressure control and profile adjustment integrated device, including an outer cylinder 1. The outer cylinder 1 is provided with an upper connecting joint 2, an outer sliding sleeve 3 and a lower connecting joint 4 connected in sequence from top to bottom. The outer sliding sleeve 3 is provided with an inner sliding sleeve 5, and the bottom of the inner sliding sleeve 5 is provided with a ball seat 6. The outer cylinder 1 is provided with a flow control and profile adjustment device 7 and a large-displacement one-way acid pressure valve 8.

[0048] The number of flow control and profile adjustment devices 7 and large-displacement one-way acid pressure valves 8 is set according to needs. The flow control and profile adjustment devices 7 and large-displacement one-way acid pressure valves 8 are respectively arranged at intervals on the outer cylinder 1 and are evenly distributed in a ring. The flow control and profile adjustment devices 7 are arranged in 1 to 2 rings, with 2 devices in each ring, for a total of 2 to 4 devices. The large-displacement one-way acid pressure valves 8 are arranged in 3 to 4 rings, with 3 devices in each ring, for a total of 9 to 12 devices.

[0049] The main function of the outer cylinder 1 is to create a sealed space. The flow control and profile adjustment device 7 and the large-displacement one-way acid pressure valve 8 are installed on the cylinder wall of the outer cylinder 1, so that the fluid outside or inside the outer cylinder can only flow through the flow control and profile adjustment device 7 and the large-displacement one-way acid pressure valve 8.

[0050] Furthermore, the upper part of the outer cylinder 1 is provided with an upper connector 9, which is normally connected to the tubing or other upper completion string tools. The upper connector 9 is connected to the upper connecting connector 2 through the upper connector male thread connector 10, and the upper connector 9 and the inner wall of the outer cylinder 1 are provided with an upper connector sealing ring 11 to prevent external fluid from entering the device through the gap between the upper connector 9 and the outer cylinder 1. The lower part of the outer cylinder 1 is provided with a lower connector 12, which is normally connected to the tubing or other lower completion string tools. The lower connector 12 is connected to the lower connecting connector 4 through the lower connector male thread connector 13, and the lower connector 12 and the inner wall of the outer cylinder 1 are provided with a lower connector sealing ring to prevent external fluid from entering the device through the gap between the lower upper connector 12 and the outer cylinder 1.

[0051] Furthermore, a certain gap exists between the upper connecting joint 2, the outer sliding sleeve 3, and the lower connecting joint 4 and the outer cylinder 1 to form an internal flow cavity 14. The upper part of the outer sliding sleeve 3 is connected to the upper connecting joint 2, blocking the inner sliding sleeve 5, which facilitates the installation and sealing of the inner sliding sleeve 5 and the outer sliding sleeve 3; the lower part of the outer sliding sleeve 3 is connected to the lower connecting joint 4, and cooperates with the upper connecting joint 2, and is installed in the upper joint 9, the lower joint 12 and the outer cylinder, thereby forming a sliding opening structure and forming a sealing and inner sliding sleeve travel space.

[0052] Furthermore, the outer sliding sleeve 3 is provided with an acid pressure injection hole 15, and the inner sliding sleeve 5 is disposed inside the outer sliding sleeve 3 and fixedly connected by a pin 16, with the inner sliding sleeve 5 blocking the acid pressure injection hole 15.

[0053] The bottom of the inner sliding sleeve 5 is equipped with a ball seat 6. When a ball is dropped from the wellhead onto the ball seat 6 and pressurized, the ball blocks the ball seat 6 to form a pressure blockage. The pressure pushes the ball seat 6 and drives the inner sliding sleeve 5 to move downward. When the pressure is greater than the shear value of the pin 16, the pin 16 is sheared, the inner sliding sleeve 5 moves downward, and the acid injection hole 15 sealed by the inner sliding sleeve 5 is leaked out. At this time, the acid injected into the completion tubing can enter the internal flow chamber 14 through the acid injection hole 15, and then enter the wellbore through the flow control and profile adjustment device 7 and the large-displacement one-way acid pressure valve 8, and enter the reservoir, thus completing the acid pressure. After the inner sliding sleeve 5 slides open, it will remain open.

[0054]

Example 2

[0055] like Figure 2 As shown, this embodiment provides a differential pressure type single-flow acid pressure control and profile adjustment integrated device, including an outer cylinder 1. The outer cylinder 1 is provided with an upper connector 2, an outer sliding sleeve 3 and a lower connector 4 arranged sequentially from the upper right to the lower. The outer sliding sleeve 3 is provided with an inner sliding sleeve 5. The upper part of the inner sliding sleeve 5 is provided with a large cross section 17 and the lower part is provided with a small cross section 18. The outer cylinder 1 is provided with a flow control and profile adjustment device 7 and a large displacement one-way acid pressure valve 8.

[0056] The number of flow control and profile adjustment devices 7 and large-displacement one-way acid pressure valves 8 is set according to needs. The flow control and profile adjustment devices 7 and large-displacement one-way acid pressure valves 8 are respectively arranged at intervals on the outer cylinder 1 and are evenly distributed in a ring. The flow control and profile adjustment devices 7 are arranged in 1 to 2 rings, with 2 devices in each ring, for a total of 2 to 4 devices. The large-displacement one-way acid pressure valves 8 are arranged in 3 to 4 rings, with 3 devices in each ring, for a total of 9 to 12 devices.

[0057] The main function of the outer cylinder 1 is to create a sealed space. The flow control and profile adjustment device 7 and the large-displacement one-way acid pressure valve 8 are installed on the cylinder wall of the outer cylinder 1, so that the fluid outside or inside the outer cylinder can only flow through the flow control and profile adjustment device 7 and the large-displacement one-way acid pressure valve 8.

[0058] Furthermore, the upper part of the outer cylinder 1 is provided with an upper connector 9, which is normally connected to the tubing or other upper completion string tools. The upper connector 9 is connected to the upper connecting connector 2 through the upper connector male thread connector 10, and the upper connector 9 and the inner wall of the outer cylinder 1 are provided with an upper connector sealing ring 11 to prevent external fluid from entering the device through the gap between the upper connector 9 and the outer cylinder 1. The lower part of the outer cylinder 1 is provided with a lower connector 12, which is normally connected to the tubing or other lower completion string tools. The lower connector 12 is connected to the lower connecting connector 4 through the lower connector male thread connector 13, and the lower connector 12 and the inner wall of the outer cylinder 1 are provided with a lower connector sealing ring to prevent external fluid from entering the device through the gap between the lower upper connector 12 and the outer cylinder 1.

[0059] Furthermore, a certain gap exists between the upper connecting joint 2, the outer sliding sleeve 3, and the lower connecting joint 4 and the outer cylinder 1 to form an internal flow cavity 14. The upper part of the outer sliding sleeve 3 is connected to the upper connecting joint 2, blocking the inner sliding sleeve 5, which facilitates the installation and sealing of the inner sliding sleeve 5 and the outer sliding sleeve 3; the lower part of the outer sliding sleeve 3 is connected to the lower connecting joint 4, and cooperates with the upper connecting joint 2, and is installed in the upper joint 9, the lower joint 12 and the outer cylinder, thereby forming a sliding opening structure and forming a sealing and inner sliding sleeve travel space.

[0060] Furthermore, the outer sliding sleeve 3 is provided with an acid pressure injection hole 15, and the inner sliding sleeve 5 is disposed inside the outer sliding sleeve 3 and fixedly connected by a pin 16, with the inner sliding sleeve 5 blocking the acid pressure injection hole 15.

[0061] The inner sliding sleeve 5 has a large cross-section 17 at the top and a small cross-section 18 at the bottom. That is to say, the cross-section of the upper end face of the inner sliding sleeve 5 is larger than the cross-section of the lower end face. The size of the projected area of ​​the cross-section perpendicular to the direction of fluid flow in the device determines the magnitude of the force. The difference in the projected area of ​​the cross-section determines the difference in force.

[0062] After wellhead pressurization, the large cross-section 17 and small cross-section 18 of the inner sliding sleeve generate different pressure values ​​due to the difference in cross-sectional area. This pushes the inner sliding sleeve 5 to slide from the large cross-section 17 to the small cross-section 18. When the pressure difference generated by the cross-sectional area difference is greater than the shear value of the pin 16, the pin 16 is sheared, the inner sliding sleeve 5 retracts and opens, and the acid injection hole 15 sealed by the inner sliding sleeve 5 is leaked out. At this time, the acid injected into the completion tubing can enter the internal flow chamber 14 through the acid injection hole 15, and then enter the wellbore through the flow control and profile adjustment device 7 and the large-displacement one-way acid pressure valve 8, and enter the reservoir, thus completing the acid pressure. After the inner sliding sleeve slides open, it will remain open.

[0063]

Example 3

[0064] like Figure 3 As shown, the flow control and profile adjustment device 7 includes a device body. The device body is provided with an inlet 7-3, an inflow channel 7-2 and a flow control and profile adjustment oil-gas mixture diversion channel 7-1 connected sequentially from one end face to the other end face. The inlet 7-3 is located on one side of the inner wall of the outer cylinder, and the flow control and profile adjustment oil-gas mixture diversion channel 7-1 is located on the outer side of the outer cylinder.

[0065] The flow control and profile adjustment oil-gas mixture diversion channel 7-1 is a symmetrical multi-segment internal spiral channel. By changing the flow direction of the incoming mixed fluid through the multi-segment internal spiral channel, under the combined action of gravity, viscosity, and centrifugal force, oil, water, or gas phases with different viscosities and densities in the mixture with different water saturation will enter different channels. As a result, the channel length and entry time of each phase in the inlet channel 7-2 are different, thereby realizing the function of adding different inlet resistances for different phases of oil, gas, and water, and achieving the purpose of controlling the inlet profile.

[0066] During large-scale acid fracturing, the acid in the completion string enters the formation through inlet 7-3, then through inlet channel 7-2, and finally through the flow control and profile control oil-gas mixture diversion channel 7-1. A small amount of acid during the acid fracturing process can enter the formation through the flow control and profile control device.

[0067] During production, the fluid in the reservoir enters the wellbore and, through the flow control and profile control oil-gas mixture diversion channel 7-1, applies different viscous forces and additional resistances to different phases of the fluid mixture with different water saturation. Then, through the inlet channel 7-2 and the inlet 7-3, it enters the outer cylinder 1 and is thus produced. When the well tubing is completed, the packer is installed to segment the well. In different segments, the flow control and profile control devices will generate different viscous forces and additional resistances to the fluid with different water saturation, thereby playing a role in flow control and profile control on the entire wellbore inlet profile.

[0068]

Example 4

[0069] like Figure 4 As shown, the large-capacity one-way acid pressure valve 8 includes a valve body, on which an acid pressure injection port 8-1 and an acid pressure outlet 8-3 are connected to each other. An acid pressure shut-off plate 8-2 is provided on the end face of the valve body located at one end of the acid pressure outlet 8-3. A spring 8-4 is connected to the inner side of the acid pressure shut-off plate 8-2, and the other end of the spring 8-4 is fixed to the inner wall of the acid pressure outlet 8-3.

[0070] The acid injection port 8-1 is located on one side of the inner wall of the outer cylinder 1, and the acid outlet 8-3 is located on one side of the outer wall of the outer cylinder 1.

[0071] Because the outflow rate is relatively large during acid fracturing, to meet the acid fracturing flow rate requirements, it is necessary to consider the inlet and outlet orifice diameters that meet the acid fracturing flow rate requirements, as well as the number of large-capacity one-way acid fracturing valves to be installed. Since the flow control and profile control device requires flow control, its inlet and outlet orifice diameters are relatively small. To ensure that a single tubing string can simultaneously fulfill both acid fracturing and flow control / profile control functions, a large-capacity injection rate is needed when injecting acid into the reservoir. However, during production, the flow control / profile control device must be the sole inlet and outlet, thus requiring large-capacity one-way acid fracturing valves. During acid fracturing, within the completion tubing... The acid enters the valve body through the acid injection port 8-1, and after squeezing open the acid pressure closing plate 8-2, it enters the wellbore and then the reservoir through the acid pressure outlet 8-3. After acid pressure is completed, during normal production, due to the production pressure difference inside and outside the completion string and the rebound action of the spring 8-4, the large-displacement one-way acid pressure valve is closed. Therefore, during the entire production process, the large-displacement one-way acid pressure valve is in the closed state, and the oil, gas and water produced in the reservoir can only enter the completion string through the flow control and profile control device, thereby realizing the flow control and profile control function.

[0072]

Example 5

[0073] This embodiment provides a well completion string, including at least one ball-drop type single-flow acid pressure control and profile control integrated device and a differential pressure type single-flow acid pressure control and profile control integrated device disposed at the lower end of the ball-drop type single-flow acid pressure control and profile control integrated device.

[0074] The topmost ball-type single-flow acid pressure control and profile control integrated device is connected to the upper completion string, while the bottom of the differential pressure single-flow acid pressure control and profile control integrated device is connected to the downhole safety isolation valve (ball valve). A packer is installed between adjacent ball-type single-flow acid pressure control and profile control integrated devices, and a packer is installed between the ball-type single-flow acid pressure control and profile control integrated device and the differential pressure single-flow acid pressure control and profile control integrated device.

[0075] During installation, first connect the downhole safety isolation valve (ball valve), then connect the differential pressure single-flow acid pressure control and profile control integrated device. Figure 2 ) + packer, and then connect multiple ball-drop type single-flow acid fracturing control and profile control integrated devices according to the needs of staged fracturing. Figure 1 The packer assembly is connected to the upper completion string, etc. During acid fracturing, the corresponding soluble ball of the downhole safety isolation valve is first deployed to pressurize and set the segment packer and the suspended packer. Then, acid is pumped in for acid fracturing. A relatively higher pressure is applied to open the differential pressure single-flow acid fracturing and profile control integrated device for acid fracturing. After this section of acid fracturing is completed, different sections are then deployed. Figure 1 Using a soluble ball of the corresponding size, open the ball-dropping single-flow acid fracturing and profile control integrated device to perform acid fracturing. After acid fracturing of different sections is completed, release the ball, retrieve the upper completion string, and then run in tubing for production. During production, the fluid in the reservoir can only enter the bottom completion string through the flow control and profile control device before being produced. The flow control and profile control device applies different throttling pressure differentials to different phases of the gas-liquid, oil-water, or oil-gas-water three-phase fluids produced from the reservoir, thereby achieving almost no throttling pressure differential for gas, low throttling pressure differential for oil, and high throttling pressure differential for water. This enables water control of the fluid produced in different sections and achieves the function of adjusting the production profile of the entire well section.

[0076] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0077] In the description of this invention, unless otherwise stated, the terms "upper," "lower," "left," "right," "inner," "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0078] The above technical solution is only one embodiment of the present invention. For those skilled in the art, based on the principles disclosed in the present invention, it is easy to make various types of improvements or modifications, and not limited to the technical solutions described in the specific embodiments of the present invention. Therefore, the foregoing description is only a preferred option and is not restrictive.

Claims

1. A ball-throwing type single-flow acid pressure control and profile adjustment integrated device, characterized in that, The device includes an outer cylinder, inside which an upper connecting joint, an outer sliding sleeve, and a lower connecting joint are sequentially connected from top to bottom. An inner sliding sleeve is provided inside the outer sliding sleeve, and a ball seat is provided at the bottom of the inner sliding sleeve. The upper connecting joint, the outer sliding sleeve, and the lower connecting joint have a certain gap with the outer cylinder to form an internal flow cavity. An acid pressure injection hole is provided on the outer sliding sleeve, and the inner sliding sleeve blocks the acid pressure injection hole. The outer cylinder wall is equipped with a flow control and profile adjustment device and a large-capacity one-way acid pressure valve. The flow control and profile adjustment device includes a device body. The device body is provided with an inlet, an inflow channel and a flow control and profile adjustment oil-gas mixture diversion channel connected sequentially from one end face to the other end face. The inlet is located on one side of the inner wall of the outer cylinder, and the flow control and profile adjustment oil-gas mixture diversion channel is located on the outer side of the outer cylinder. The large-capacity one-way acid pressure valve includes a valve body with an acid pressure injection port and an acid pressure outlet that are interconnected. An acid pressure shut-off plate is provided on the end face of the valve body at one end of the acid pressure outlet. A spring is connected to the inner side of the acid pressure shut-off plate, and the other end of the spring is fixed to the inner wall of the acid pressure outlet. The acid pressure injection port is located on one side of the inner wall of the outer cylinder, and the acid pressure outlet is located on one side of the outer wall of the outer cylinder.

2. The ball-throwing type single-flow acid pressure control and profile adjustment integrated device according to claim 1, characterized in that, The upper part of the outer cylinder is provided with an upper connector, which is connected to the upper connecting connector through an upper connector male threaded connector, and an upper connector sealing ring is provided between the upper connector and the inner wall of the outer cylinder; The lower part of the outer cylinder is provided with a lower connector, which is connected to the lower connecting connector through a lower connector male threaded connector, and a lower connector sealing ring is provided between the lower connector and the inner wall of the outer cylinder.

3. The ball-throwing type single-flow acid pressure control and profile adjustment integrated device according to claim 1, characterized in that, The inner sliding sleeve is disposed inside the outer sliding sleeve and is fixedly connected by a pin.

4. A differential pressure type single-flow acid pressure control and profile regulation integrated device, characterized in that, The device includes an outer cylinder, inside which, from top to bottom, are arranged an upper connecting joint, an outer sliding sleeve, and a lower connecting joint. An inner sliding sleeve is provided inside the outer sliding sleeve, with a large cross-section at the top and a small cross-section at the bottom. A certain gap exists between the upper connecting joint, the outer sliding sleeve, and the lower connecting joint and the outer cylinder to form an internal flow cavity. An acid pressure injection hole is provided on the outer sliding sleeve, and the inner sliding sleeve blocks the acid pressure injection hole. The outer cylinder wall is provided with a flow control and profile adjustment device and a large-displacement one-way acid pressure valve; the flow control and profile adjustment device includes a device body, and the device body is provided with an inlet, an inflow channel and a flow control and profile adjustment oil-gas mixture diversion channel connected in sequence from one end face to the other end face. The inlet is located on one side of the inner wall of the outer cylinder, and the flow control and profile adjustment oil-gas mixture diversion channel is located on the outer side of the outer cylinder. The large-capacity one-way acid pressure valve includes a valve body with an acid pressure injection port and an acid pressure outlet that are interconnected. An acid pressure shut-off plate is provided on the end face of the valve body at one end of the acid pressure outlet. A spring is connected to the inner side of the acid pressure shut-off plate, and the other end of the spring is fixed to the inner wall of the acid pressure outlet. The acid pressure injection port is located on one side of the inner wall of the outer cylinder, and the acid pressure outlet is located on one side of the outer wall of the outer cylinder.

5. The integrated differential pressure single-flow acid pressure control and profile control device according to claim 4, characterized in that, The upper part of the outer cylinder is provided with an upper connector, which is connected to the upper connecting connector through an upper connector male threaded connector, and an upper connector sealing ring is provided between the upper connector and the inner wall of the outer cylinder; The lower part of the outer cylinder is provided with a lower connector, which is connected to the lower connecting connector through a lower connector male threaded connector, and a lower connector sealing ring is provided between the lower connector and the inner wall of the outer cylinder.

6. The differential pressure type single-flow acid pressure control and profile control integrated device according to claim 4, characterized in that, The inner sliding sleeve is disposed inside the outer sliding sleeve and is fixedly connected by a pin.

7. A completion string, characterized in that, It includes at least one ball-throwing type single-flow acid pressure control and profile control integrated device as described in any one of claims 1-3, and a differential pressure type single-flow acid pressure control and profile control integrated device as described in any one of claims 4-6, which is disposed at the lower end of the ball-throwing type single-flow acid pressure control and profile control integrated device.

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