Infinitus Intelligent Regulation Fracturing Sleeve

Abstract

The present invention relates to an infinitely adjustable intelligent fracturing sliding sleeve, which is particularly suitable for the development of unconventional oil and gas resources, such as shale gas and tight oil. The specific structure of the dart part of the infinitely adjustable intelligent fracturing sliding sleeve includes an outer housing, a lower retaining disc, an upper retaining disc, bolts, springs, snap rings, plugging balls, thrust blocks, thrust bearings, diverter blocks, motors, diverters, capacitive sensors, silicone rubber seals, control modules, and diverter end caps. When the dart part of the infinitely adjustable intelligent fracturing sliding sleeve passes through a specified position, the dart part of the infinitely adjustable intelligent fracturing sliding sleeve judges and counts each fracturing part through three capacitive sensors. When the preset value is reached, the tool switches to the activation state, impacts the plugging ball under the pressure of the drilling fluid, pushes the thrust block, and the thrust block opens the piston on the casing under the action of pressure buildup, realizing the fracturing operation. It avoids the limitation of the steel ball size in the traditional ball-drop sliding sleeve technology, reduces the operation complexity, improves the construction efficiency, and provides a new technical means for the efficient development of unconventional oil and gas.

Description

Technical Field

[0001] The invention relates to a tool for exploiting resources such as petroleum and natural gas, and in particular to a full-bore fracturing sleeve, belonging to the technical field of oil and gas field fracturing. Background Art

[0002] As global energy demand continues to grow, the oil and gas industry faces increasingly complex mining challenges, especially the rapid increase in the demand for the development of unconventional oil and gas resources. The reservoir characteristics of unconventional oil and gas resources (such as shale gas and tight oil) are completely different from those of conventional oil and gas reservoirs. They usually have low permeability and low porosity, which makes the oil and gas mobility extremely poor and cannot be efficiently developed through traditional completion and production technologies. Therefore, how to effectively improve the recovery rate of unconventional oil and gas reservoirs has become a key issue that the global oil and gas industry needs to solve. Against this background, staged fracturing technology has rapidly emerged and become an important means of developing unconventional oil and gas reservoirs. Staged fracturing technology uses fracturing fluid to break the rocks in the formation and form a complex fracture network, thereby providing more channels for oil and gas flow. This technology can greatly improve the recovery rate of the reservoir, allowing unconventional oil and gas resources that are difficult to exploit to be commercially developed. Among all staged fracturing technologies, the ball-dropping sliding sleeve technology is particularly common, and is widely used in horizontal wells and multi-stage fracturing wells due to its advantages of simple operation and high operating efficiency. However, one of the core challenges of the ball-throwing sleeve technology is the limitation of its steel ball size. In this technology, the sleeve of each well section relies on the steel ball entering the ball seat to trigger the opening of the sleeve. The size of the sleeve ball seat of different well sections needs to be increased in sequence to ensure that the steel balls can be inserted into their respective ball seats in sequence and complete the opening of the sleeve. Therefore, the steel balls are thrown in from small to large, and each sleeve corresponds to a steel ball of a specific size. Although this design achieves controllable multi-stage fracturing in operation, it also brings obvious limitations. As the number of fracturing stages increases, the difference in steel ball size gradually decreases, and the precision requirements for operation are getting higher and higher. A slight deviation may cause the sleeve to fail to open normally or the steel ball to fail to fully embed into the ball seat. Faced with these challenges, the oil and gas industry is in urgent need of an innovative fracturing tool that can break through the limitations of traditional ball-throwing sleeve technology. The ideal fracturing technology should have the following characteristics: first, it can achieve precise positioning during the fracturing process to ensure that the position of each sleeve in the well can be accurately controlled and identified; second, the technology should have the advantage of unlimited number of fracturing stages, solving the operational complexity and risks brought about by the gradual reduction in steel ball size differences in traditional sleeve technology; in addition, the new fracturing tool should have the characteristics of low cost, easy operation, strong adaptability, etc., and be able to cope with the increasingly complex needs of unconventional oil and gas extraction. Summary of the invention

[0003] In view of the above technical deficiencies, the present invention provides an infinitely variable intelligent control fracturing sliding sleeve, which can not only achieve infinite levels, but also accurately locate the fracturing position through its own detection system to realize precise fracturing.

[0004] The technical solution of the present invention: A dart part of an infinitely variable intelligent control fracturing sliding sleeve includes a housing, a lower retaining disc, an upper retaining disc, bolts, springs, snap rings, plugging balls, thrust blocks, thrust bearings, a diverter block, a motor, a diverter, a capacitive sensor, a silicone rubber seal, a control module, and a diverter end cover. Among them, a pressure buildup part and a mode conversion part are provided in the housing. The pressure buildup part mainly consists of a lower retaining disc, an upper retaining disc, bolts, springs, snap rings, plugging balls, and thrust blocks. The pressure buildup part is cooperated by the snap ring, the lower retaining disc and the thrust block, and is fixed to the upper retaining disc by bolts. A spring is placed between the upper retaining disc and the thrust block; the mode conversion part mainly consists of a motor, a diverter, a capacitive sensor, and a control module. The control module includes a motor power supply control and a control board. The motor, the capacitive sensor, and the control module are installed in the diverter and sealed and fixed with the diverter end cover. The mode conversion part is installed in the groove opened correspondingly on the housing to limit the circumferential rotation and axial positioning of the mode conversion part.

[0005] Further, in the pressure buildup part, there are six plugging balls and six snap rings, three at the top and three at the bottom.

[0006] Further, three grooves are evenly opened in the circumferential direction on the housing corresponding to the mode conversion part, and the grooves extend from the top of the housing to the first step of the inner hole of the housing; three through holes are also opened on the circumference of the housing at the corresponding capacitive sensors for placing silicone rubber seals.

[0007] The dart part of the infinitely variable intelligent control fracturing sliding sleeve detects the position of the casing piston of the downhole sliding sleeve through a capacitive sensor. When the specified fracturing position is reached, the control module is used to drive the motor to convert the flow path, and the pressure buildup of the plugging ball and the action of the thrust block are used to realize the fracturing operation. When the main feature of the infinitely variable intelligent control fracturing sliding sleeve is not activated, the drilling fluid flows out from the middle, and the thrust block retracts inward under the action of the spring, and the dart part can pass through any casing; when activated, the drilling fluid flows through the plugging ball flow path and generates pressure buildup. The pressure buildup pushes the plugging ball and the thrust block, causing the shear pin of the sliding sleeve piston on the outer casing sliding sleeve to be sheared off, and then opening the oil inlet hole on the outer casing sliding sleeve, thereby realizing downhole fracturing. In addition, after the fracturing is completed, the control module drives the motor to return to the unactivated state, and the dart part of the infinitely variable intelligent control fracturing sliding sleeve can continue to pass through the downhole sliding sleeve position without affecting subsequent fracturing operations.

[0008] The beneficial effects of the present invention are as follows: (1) It can well solve the maximum number of fracturing stages supported by the traditional sliding sleeve technology and achieve stepless fracturing. (2) It can return to the unactivated state after fracturing. The dart part of the infinitely adjustable intelligent fracturing sliding sleeve can continue to pass through any sliding sleeve position in the wellbore, ensuring the borehole diameter performance of the wellbore, reducing the resistance of downhole operations, and not affecting subsequent fracturing operations. (3) The infinitely adjustable intelligent fracturing sliding sleeve is triggered by three capacitive sensors simultaneously to ensure reaching the pre-fracturing position and achieve precise fracturing. Brief Description of the Drawings

[0009] Attached Figure 1 is a structural diagram of the dart part of the infinitely adjustable intelligent fracturing sliding sleeve of the present invention;

[0010] Attached Figure 2 is a cross-sectional view taken along the line C-C of the dart part of the infinitely adjustable intelligent fracturing sliding sleeve of the present invention;

[0011] Attached Figure 3 is a schematic structural diagram of the diverter of the infinitely adjustable intelligent fracturing sliding sleeve of the present invention;

[0012] Attached Figure 4 is a schematic structural diagram of the outer casing sliding sleeve for supplementary explanation;

[0013] Attached Figure 5 is a flowchart of the working principle of the infinitely adjustable intelligent fracturing sliding sleeve of the present invention.

[0014] Reference numerals and corresponding component names in the drawings: 1 - outer casing, 2 - lower retaining disc, 3 - upper retaining disc, 4 - bolt, 5 - spring, 6 - snap ring, 7 - plug ball, 8 - thrust block, 9 - thrust bearing, 10 - diverter block, 11 - motor, 12 - diverter, 13 - capacitive sensor, 14 - silicone rubber seal, 15 - control module, 16 - diverter end cap, 17 - sliding sleeve upper joint, 18 - sliding sleeve pin, 19 - sliding sleeve piston, 20 - sliding sleeve lower joint. Detailed Embodiment

[0015] In the present invention, for better description of the relative positional relationship of each component, the directions in the attached drawings of the specification are referred to. All mentioned up and down positional relationships, etc., are determined and described based on the directions shown in the attached drawings to ensure the accuracy of the positions of each component and the consistency of the description. Figure 1 in the drawings. All the mentioned up and down positional relationships, etc., are determined and described based on the directions shown in the attached drawings to ensure the accuracy of the positions of each component and the consistency of the description. Figure 1 shown in the drawings to ensure the accuracy of the positions of each component and the consistency of the description.

[0016] The present invention will be further described below with reference to the drawings:

[0017] Refer to the attached Figure 1, An infinitely variable intelligent control fracturing sliding sleeve dart part, including an outer housing 1, a lower retaining disc 2, an upper retaining disc 3, bolts 4, a spring 5, a snap ring 6, a plugging ball 7, a thrust block 8, a thrust bearing 9, a diverter block 10, a motor 11, a diverter 12, a capacitive sensor 13, a silicone rubber seal 14, a control module 15, and a diverter end cover 16.

[0018] See the appendix Figure 4 , Supplementary description of the outer casing sliding sleeve at the fracturing location. The outer casing sliding sleeve includes a sliding sleeve upper sub 17, a sliding sleeve pin 18, a sliding sleeve piston 19, and a sliding sleeve lower sub 20.

[0019] The described outer casing sliding sleeve goes down the well together with the casing. There is an outer casing sliding sleeve at regular intervals inside the downhole casing. By detecting the number of outer casing sliding sleeve pistons passed, the position in the well can be calculated, and thus the precise positioning of the stepless fracturing can be achieved.

[0020] The working principle of the infinitely variable intelligent control fracturing sliding sleeve is mainly as follows. When the infinitely variable intelligent control fracturing sliding sleeve dart part passes through the outer casing sliding sleeve piston 19, the three circumferential capacitive sensors 13 on the infinitely variable intelligent control fracturing sliding sleeve dart part will detect the outer casing sliding sleeve piston 19, and the three capacitive sensors 13 will be triggered simultaneously. The control module 15 calculates the next fracturing position in the well based on this. If the specified position is reached, the control module 15 controls the motor 11 to rotate, and the motor 11 drives the diverter block 10 to switch the flow path. When not activated, the diverter block 10 opens the left flow path shown in the appendix Figure 1 . There are three flow path through holes on the diverter block 10, corresponding to the three flow paths leading to the middle on the outer housing 1. The drilling fluid flows out from the middle and will not cause a pressure buildup effect. The infinitely variable intelligent control fracturing sliding sleeve dart part can pass through any outer casing sliding sleeve; when activated, the diverter block 10 opens the right flow path shown in the appendix Figure 1 . The state shown in the appendix is the activated state. The drilling fluid will not flow out from the middle flow path, and the drilling fluid flows to the right flow path, impacting the plugging ball 7 to form a pressure buildup. The plugging ball 7 pushes the thrust block 8 to move outwards. At the same time, since the drilling fluid cannot flow out normally, the pressure buildup generated will produce a huge downward force, causing the entire infinitely variable intelligent control fracturing sliding sleeve dart part to move downwards. Under the action of the drilling fluid, the extended part of the thrust block 8 will drive the sliding sleeve piston 19 of the outer casing sliding sleeve to cut off the sliding sleeve pin 18, thereby opening the oil inlet hole of the outer casing sliding sleeve and realizing the fracturing function. After the fracturing is completed, that is, after the infinitely variable intelligent control fracturing sliding sleeve dart part opens the oil inlet hole on the outer casing sliding sleeve, the control module 15 drives the motor to switch the flow path back to the unactivated state. Under the action of the spring 5, the thrust block 8 retracts inwards, and the infinitely variable intelligent control fracturing sliding sleeve dart part can continue to pass through the downhole casing and the outer casing sliding sleeve without hindering subsequent fracturing operations.

[0021] The above is only an example and illustration of the structure of the present invention. Those skilled in the art can make various modifications and supplements to the specific embodiments, or use similar methods for substitution. As long as they do not deviate from the core structure of the present invention or exceed the scope defined by the claims of this patent right, all such modifications and alternative solutions should be covered within the protection scope of the present invention.

Claims

1. The Infinitus intelligent control fracturing sliding sleeve is characterized in that: The dart part of the Infinitus intelligent control fracturing sliding sleeve consists of an outer housing (1), a lower retaining disc (2), an upper retaining disc (3), bolts (4), a spring (5), a snap ring (6), a plugging ball (7), a thrust block (8), a thrust bearing (9), a diverter block (10), a motor (11), a diverter (12), a capacitive sensor (13), a silicone rubber seal (14), a control module (15), and a diverter end cover (16); among them, a pressure buildup part and a mode conversion part are provided inside the outer housing (1). The pressure buildup part mainly consists of a lower retaining disc (2), an upper retaining disc (3), bolts (4), a spring (5), a snap ring (6), a plugging ball (7), and a thrust block (8). The pressure buildup part is cooperated by the snap ring (6), the lower retaining disc (2), and the thrust block (8), and is fixed to the upper retaining disc (3) by bolts (4), and a spring (5) is placed between the upper retaining disc (3) and the thrust block (8); the mode conversion part mainly consists of a motor (11), a diverter (12), a capacitive sensor (13), and a control module (15). The control module includes a motor power supply control and a control board. The motor (11), the capacitive sensor (13), and the control module (15) are installed inside the diverter (12) and are sealed and fixed with the diverter end cover (16). The mode conversion part is installed in the groove correspondingly opened on the outer housing (1) to limit the circumferential rotation and axial positioning of the mode conversion part.

2. The infinitely adjustable fracturing sliding sleeve according to claim 1, characterized in that: For the pressure buildup part, there are six plugging balls (7) and six snap rings (6), three at the top and three at the bottom.

3. The infinitely adjustable fracturing sliding sleeve according to claim 1, characterized in that: On the outer housing (1) corresponding to the mode conversion part, three grooves are evenly opened in the circumferential direction. The grooves extend from the top of the outer housing (1) to the first step of the inner hole of the outer housing (1); three through holes are also opened on the circumference of the outer housing (1) at the corresponding positions of the capacitive sensors (13) for placing the silicone rubber seals (14).

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