Electrically controlled cluster fracturing sleeve with pressure signal opening

Abstract

The application provides an electrically-controlled cluster fracturing sliding sleeve with pressure signal opening, which comprises an electrically-controlled delay toe-end sliding sleeve configured to open a fracturing hole according to a pressure signal applied at a wellhead; an electrically-controlled cluster fracturing sliding sleeve which is identical in structure to the electrically-controlled delay toe-end sliding sleeve and requires a different pressure signal to open the fracturing hole; and an electrically-controlled segmented fracturing sliding sleeve which opens a ball catcher according to a pressure applied at the wellhead and is connected to the ball catcher and opens a fracturing hole after a soluble fracturing ball is put in; wherein the electrically-controlled delay toe-end sliding sleeve is arranged at the lowermost end, and above the electrically-controlled delay toe-end sliding sleeve, a plurality of electrically-controlled segmented fracturing sliding sleeves are arranged to divide the electrically-controlled delay toe-end sliding sleeve into a plurality of segments, and one or more electrically-controlled cluster fracturing sliding sleeves are arranged in each segment.

Description

TECHNICAL FIELD

[0001] The present application relates to a pressure signal opening electric control cluster fracturing sliding sleeve, belonging to the technical field of completion tool equipment. BACKGROUND

[0002] The main method of increasing production of oil and gas well completion is fracturing technology, in which pumping bridge plug and perforation are combined as the main completion method of shale gas. The first perforation technology needs to spend a long time and cost in well site operation. With more and more deep shale gas and ultra-long horizontal section wells, the cementing sliding sleeve fracturing technology is gradually popularized and applied to replace the soluble bridge plug fracturing because it can realize rapid and efficient development of shale gas wells and solve the problem of limited operation of coiled tubing to establish the first fracturing channel in deep well long horizontal section. The toe sliding sleeve in the existing cementing fracturing sliding sleeve has low opening precision because of the use of shear pin and rupture disc opening method, and there is a risk of early opening when the cementing and fracturing construction pressure is close. The multi-stage fracturing sliding sleeve has a complex cluster opening structure, which reduces the reliability. The existing electric control sliding sleeve has the problems of high cost, short working time and difficult popularization and application. SUMMARY

[0003] In view of the above technical problems existing in the prior art, the present application provides a pressure signal opening electric control cluster fracturing sliding sleeve, which has an innovative design of an electromagnetic hydraulic lock with low cost and high precision pressure control, realizes ultra-high pressure locking and opening control of the fracturing sliding sleeve, and eliminates the pressure-related risk in operation.

[0004] The present application provides a pressure signal opening electric control cluster fracturing sliding sleeve, which comprises:

[0005] An electric control delay toe end sliding sleeve configured to open a fracturing hole according to the pressure applied at the wellhead;

[0006] An electric control cluster fracturing sliding sleeve having the same structure as the electric control delay toe end sliding sleeve and different pressure required for opening the fracturing hole; and

[0007] An electric control segmented fracturing sliding sleeve configured to open a ball catcher according to the pressure applied at the wellhead, and open a fracturing hole after a soluble fracturing ball is put into the ball catcher;

[0008] The electric control delay toe end sliding sleeve is arranged at the lowermost end, and the upper part thereof is divided into several segments by a plurality of electric control segmented fracturing sliding sleeves, and one or more electric control cluster fracturing sliding sleeves are arranged in each segment.

[0009] The present application is further improved in that the pressure at which the electric control delay toe end sliding sleeve opens the fracturing hole is the same as the pressure at which the electric control segmented fracturing sliding sleeve at the lowermost end opens the ball catcher; and the pressure at which all electric control cluster fracturing sliding sleeves in each segment open the fracturing hole is the same as the pressure at which the electric control segmented fracturing sliding sleeve at the upper end of the segment opens the ball catcher.

[0010] The further improvement of the present application is that the electrically controlled delay toe-end sliding sleeve comprises a first sliding sleeve body, the upper part of the first sliding sleeve body is provided with a fracturing hole, and the inside of the first sliding sleeve body is provided with a first inner sleeve; the lower part of the first sliding sleeve body is provided with a first electrically controlled short section;

[0011] The first inner sleeve blocks the fracturing hole in the initial state, when the pressure applied at the well head matches the pressure set by the first electrically controlled short section, the first inner sleeve slides downward and makes the fracturing hole open.

[0012] The further improvement of the present application is that a first annular hydraulic cavity is arranged between the first sliding sleeve body and the first inner sleeve, a first annular cavity is arranged in the first electrically controlled short section, and a pressure sensing unit, a first electromagnetic hydraulic lock and a high-temperature-resistant battery pack are arranged in the first annular cavity;

[0013] The first annular hydraulic cavity is filled with hydraulic oil, the first inner sleeve is blocked to be fixed, the first electromagnetic hydraulic lock locks the pressure in the first annular pressure hydraulic cavity, the pressure sensing unit detects and calculates whether the pressure applied at the well head reaches the set value, and when the set value is reached, the first electromagnetic hydraulic lock unlocks the pressure in the first annular hydraulic cavity.

[0014] The further improvement of the present application is that the first annular cavity and the first annular hydraulic cavity are connected through a first small hole, the pressure sensing unit extends into the first small hole and detects the pressure in the first small hole and the first annular cavity, so as to calculate the pressure applied at the well head and compare it with the set pressure.

[0015] The further improvement of the present application is that the first annular cavity and the first annular hydraulic cavity are also connected through a second small hole, and the first electromagnetic hydraulic lock blocks the second small hole when it is extended and makes the second small hole open when it is retracted.

[0016] The further improvement of the present application is that the electrically controlled segmented fracturing sliding sleeve comprises a second sliding sleeve body, the upper part of the second sliding sleeve body is provided with a fracturing hole, and the inside of the second sliding sleeve body is provided with a second inner sleeve; the lower part of the second sliding sleeve body is provided with a ball catcher and a second electrically controlled short section;

[0017] The second inner sleeve blocks the fracturing hole in the initial state, when the pressure applied at the well head matches the pressure set by the first electrically controlled short section, the second inner sleeve slides downward by a first segment and makes the ball catcher open, and after the soluble fracturing ball is put in, the second inner sleeve continues to move downward and makes the fracturing hole open.

[0018] The further improvement of the present application is that a second annular hydraulic cavity is arranged between the second sliding sleeve body and the second inner sleeve, a second annular cavity is arranged in the second electric control nipple, and a pressure sensing unit, a second electromagnetic hydraulic lock and a high-temperature-resistant battery group are arranged in the second annular cavity.

[0019] The second annular hydraulic cavity is filled with hydraulic oil, and the blocked pressure blocks the second inner sleeve to be fixed, the second electromagnetic hydraulic lock locks the pressure in the second annular hydraulic cavity at the beginning, the pressure sensing unit detects and calculates whether the pressure applied at the wellhead reaches the set value, and when the set value is reached, the second electromagnetic hydraulic lock unlocks the pressure in the second annular hydraulic cavity.

[0020] The further improvement of the present application is that the second annular cavity and the second annular hydraulic cavity are further connected through a third small hole, and the second electromagnetic hydraulic lock blocks the third small hole when it is extended, and opens the third small hole when it is retracted.

[0021] The further improvement of the present application is that the ball catcher comprises a fixed ring and a variable-diameter ball seat arranged between the fixed ring and the second inner sleeve, and when the second inner sleeve pushes the variable-diameter ball seat, the variable-diameter ball seat is retracted inwardly and clamped on the fixed ring.

[0022] The further improvement of the present application is that the fixed ring and the second electric control nipple are connected through a shear pin.

[0023] Compared with the prior art, the present application has the following advantages:

[0024] The electric control cluster fracturing sliding sleeve with pressure signal opening provided by the present application has an electromagnetic hydraulic lock with high-precision pressure control, realizes ultra-high pressure locking and opening control of the fracturing sliding sleeve, and eliminates the pressure-related risks in operation. The electric control cluster fracturing sliding sleeve with pressure signal opening has a unique electronic programming design, can customize the opening pressure signal of the sliding sleeve, realizes cluster precise fracturing of the sliding sleeve, and finally forms an infinite cluster fracturing sliding sleeve technology for deep and long horizontal wells, and supports rapid, economic and efficient development of shale gas.

[0025] The cluster electric control fracturing sliding sleeve has good adaptability to oil and gas wells with different pressure requirements. Since the locking force of the electromagnetic hydraulic lock on the sliding sleeve is high enough, the sliding sleeve almost has no risk of early opening in the operation process, and therefore it is not necessary to adjust the locking force of the sliding sleeve according to the pressure conditions of the oil and gas well.

[0026] The application realizes large-diameter design, unlimited step number, and opening of specified sliding sleeve by pressure signal applied at wellhead. The driving force of electrically-controlled sliding sleeve opening is fluid pressure in well, and the electrically-controlled system only provides locking function of the sliding sleeve, which not only realizes miniaturization of the electrically-controlled system, but also reduces cost of the sliding sleeve, and the structure of the sliding sleeve is completely consistent with the same type, and only needs to set relevant parameters in the electrically-controlled system before entering well, so as to further reduce production cost of the sliding sleeve and facilitate series management. BRIEF DESCRIPTION OF DRAWINGS

[0027] The preferred embodiments of the application will be described in detail below with reference to the accompanying drawings, in which:

[0028] Figure 1 Fig. 1 shows a structure schematic diagram of the electrically-controlled cluster fracturing sliding sleeve opened by pressure signal according to one embodiment of the application;

[0029] Figure 2 Fig. 2 shows a structure schematic diagram of the electrically-controlled delay toe sliding sleeve according to one embodiment of the application, showing the structure in initial state;

[0030] Figure 3 Fig. 3 shows a structure schematic diagram of the electrically-controlled delay toe sliding sleeve according to one embodiment of the application, showing the structure in fracturing hole opening state;

[0031] Figure 4 Fig. 4 shows a structure schematic diagram of the electrically-controlled staged fracturing sliding sleeve according to one embodiment of the application, showing the structure in initial state;

[0032] Figure 5 Fig. 5 shows a structure schematic diagram of the electrically-controlled staged fracturing sliding sleeve according to one embodiment of the application, showing the structure in ball catcher opening state;

[0033] Figure 6 Fig. 6 shows a structure schematic diagram of the electrically-controlled staged fracturing sliding sleeve according to one embodiment of the application, showing the state after fracturing ball is put in.

[0034] In the drawings, the same components are designated by the same reference numerals. The drawings are not drawn according to actual scale.

[0035] In the drawings, the meanings of various reference numerals are as follows:

[0036] 100, electrically controlled delay toe sleeve, 200, electrically controlled segmented sleeve, 300, electrically controlled cluster sleeve, 110, first sleeve body, 111, upper joint, 112, fracturing hole, 120, first inner sleeve, 121, first annular hydraulic cavity, 130, first electrically controlled nipple, 131, first annular cavity, 132, first small hole, 133, second small hole, 134, pressure sensing unit, 135, first electromagnetic hydraulic lock, 210, second sleeve body, 211, upper joint, 212, fracturing hole, 220, second inner sleeve, 221, second annular hydraulic cavity, 230, second electrically controlled nipple, 231, second annular cavity, 232, third small hole, 233, second electromagnetic hydraulic lock, 240, ball catcher, 241, fixed ring, 242, variable-diameter ball seat, 243, shear pin, 250, soluble fracturing ball. DETAILED DESCRIPTION

[0037] In order to make the technical solutions and advantages of the present application clearer, the exemplary embodiments of the present application are further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present application, not an exhaustive enumeration of all embodiments. And in the case of no conflict, the embodiments in the present application and the features in the embodiments can be combined with each other.

[0038] Figure 1 An electrically controlled cluster sleeve opened by a pressure signal according to the present application is schematically shown, including an electrically controlled delay toe sleeve 100, an electrically controlled cluster sleeve 300 and an electrically controlled segmented sleeve 200. The electrically controlled delay toe sleeve 100 opens a fracturing hole 112 according to the pressure applied at the wellhead, the electrically controlled cluster sleeve 300 has the same structure as the electrically controlled delay toe sleeve 100, and the pressure required to open the fracturing hole 112 is different.

[0039] The electrically controlled segmented sleeve 200 opens a ball catcher 240 according to the pressure applied at the wellhead, and the fracturing hole is opened after a soluble fracturing ball 250 is put into the ball catcher 240.

[0040] Among them, the electrically controlled delay toe sleeve 100 is arranged at the lowermost end, and above it is divided into several segments by several electrically controlled segmented sleeves 200, and one or more electrically controlled cluster sleeves 300 are arranged in each segment.

[0041] In one embodiment, the pressure required for the electrically controlled delay toe sleeve 100 to open the fracturing hole 112 is the same as the pressure required for the electrically controlled segmented sleeve 200 at the lowermost end to open the ball catcher 240; the pressure required for all electrically controlled cluster sleeves 300 in each segment to open the fracturing hole 112 is the same as the pressure required for the electrically controlled segmented sleeve 200 at the upper end of the segment to open the ball catcher 240.

[0042] When the electrically controlled cluster fracturing sliding sleeve is opened by the pressure signal according to the embodiment, the opening pressure signal of each section is different. When the sliding sleeve needs to be opened, a pressure signal is applied through the wellhead, the electrically controlled delay toe sliding sleeve 100 opens the fracturing hole 112 to start fracturing operation, and the ball catcher 240 of the lowermost electrically controlled segmented fracturing sliding sleeve 200 is opened. When the fracturing operation of the section is completed, the soluble fracturing ball 250 is put in, the soluble fracturing ball 250 is connected with the ball catcher 240 and the fracturing hole 112 of the electrically controlled segmented fracturing sliding sleeve 200 is opened. After a pressure signal is applied through the wellhead, the electrically controlled cluster fracturing sliding sleeve 300 of the section opens the fracturing hole 112 to start fracturing operation, and the ball catcher 240 of the uppermost electrically controlled segmented fracturing sliding sleeve 200 of the section is opened. When the fracturing operation of the section is completed, the soluble fracturing ball 250 is put in again, the soluble fracturing ball 250 is connected with the ball catcher 240 and the fracturing hole 112 of the electrically controlled segmented fracturing sliding sleeve 200 is opened. The pressure signal of the wellhead is changed again to complete the fracturing operation of each section in turn.

[0043] In one embodiment, the electrically controlled delay toe sliding sleeve 100 comprises a first sliding sleeve body 110, which is in a cylindrical structure, and is provided with an upper joint at the upper end and a fracturing hole 112 on the side wall of the upper part. A first inner sleeve 120 is arranged in the inside of the first sliding sleeve body 110, and a first electrically controlled short section 130 is arranged below the first sliding sleeve body 110. The first electrically controlled short section 130 can detect the pressure in the well at the electrically controlled delay toe sliding sleeve 100 and act in comparison with the set pressure.

[0044] The first inner sleeve 120 blocks the fracturing hole 112 in the initial state, and when the pressure applied through the wellhead matches the pressure set by the first electrically controlled short section 130, the first inner sleeve 120 slides downward and opens the fracturing hole 112.

[0045] In the embodiment, a pressure waveform is preferably set in the first electrically controlled short section 130, which contains pressure amplitude, width and number. These parameters are compared with the pressure applied through the wellhead, and if they match, the fracturing hole 112 is opened.

[0046] In a preferred embodiment, a first annular hydraulic cavity 121 is arranged between the first sliding sleeve body 110 and the first inner sleeve 120, a first annular cavity 131 is arranged in the first electrically controlled short section 130, and a pressure sensing unit 134 and a first electromagnetic hydraulic lock 135 are arranged in the first annular cavity. In the embodiment, the pressure sensing unit 134 detects the pressure applied through the wellhead and compares it with the set pressure waveform, and the electromagnetic hydraulic lock can lock or unlock the first inner sleeve 120 to fix or move it.

[0047] The pressure in the first annular hydraulic cavity 121 blocks the first inner sleeve 120 from moving, and the first electromagnetic hydraulic lock 135 locks the pressure in the first annular hydraulic cavity 121, and the pressure sensing unit 134 detects and calculates whether the pressure applied at the wellhead reaches the set value, and when the set value is reached, the first electromagnetic hydraulic lock 135 unlocks the pressure in the first annular hydraulic cavity 121.

[0048] In one embodiment, the first annular cavity 131 and the first annular hydraulic cavity 121 are connected through a first small hole 132, and the pressure sensing unit 134 extends into the first small hole 132 and detects the pressure in the first small hole 132 and the first annular hydraulic cavity 121, thereby calculating the pressure applied at the wellhead and comparing it with the set pressure.

[0049] The pressure applied at the wellhead acts on the first inner sleeve 120, thereby reflecting into the first annular hydraulic cavity 121 and the first small hole 132, and the pressure sensing unit 134 detects the pressure in the first small hole 132 to calculate the pressure applied at the wellhead.

[0050] In a preferred embodiment, the first annular cavity 131 and the first annular hydraulic cavity 121 are also connected through a second small hole 133, and the first electromagnetic hydraulic lock 135 blocks the second small hole 133 when it is extended and opens the second small hole 133 when it is retracted.

[0051] In the initial state, the first electromagnetic hydraulic lock 135 is in the extended state, blocking the second small hole 133, at which time the pressure in the first annular hydraulic cavity 121 blocks the first inner sleeve 120 from moving. After the pressure sensing unit 134 detects the pressure in the small hole to calculate the pressure applied at the wellhead, the pressure is compared with the set pressure, and if they match, the first electromagnetic contraction opens the second small hole 133 and releases the pressure in the first annular hydraulic cavity 121, and the first inner sleeve 120 moves downward under the pressure of the central hole, thereby exposing the fracturing hole 212.

[0052] In one embodiment, the electrically controlled staged fracturing sleeve 200 includes a second sleeve body 210, which is a cylindrical structure similar in structure to the first sleeve body 110. The upper part of the second sleeve body 210 is provided with a fracturing hole 212, and the inside is provided with a second inner sleeve 220; the lower part of the second sleeve body 210 is provided with a ball catcher 240 and a second electrically controlled short section 230.

[0053] The second inner sleeve 220 blocks the fracturing hole 212 in the initial state, and slides downward by a distance to open the ball catcher 240 when the pressure applied at the well head matches the pressure set by the first electric control nipple 130, and continues to move downward and open the fracturing hole 212 after the soluble fracturing ball 250 is put in.

[0054] In one embodiment, a second annular hydraulic cavity 221 is arranged between the second sliding sleeve body 210 and the second inner sleeve 220, a second annular cavity 231 is arranged in the second electric control nipple 230, and an electromagnetic hydraulic lock is arranged in the second annular cavity 231.

[0055] The second annular hydraulic cavity 221 is filled with hydraulic oil, which blocks the second inner sleeve 220 and fixes it in place. In the initial state, the second electromagnetic hydraulic lock 233 locks the pressure in the second annular hydraulic cavity 221, and when the pressure applied at the well head reaches the set value, the second electromagnetic hydraulic lock 233 unlocks the pressure in the annular hydraulic cavity.

[0056] In a preferred embodiment, the second annular cavity 231 and the second annular hydraulic cavity 221 are further connected through a third small hole 232, and the second electromagnetic hydraulic lock 233 blocks the third small hole 232 when it is extended and opens the third small hole 232 when it is retracted.

[0057] In one embodiment, the ball catcher 240 includes a fixed ring 241 and a variable-diameter ball seat 242 arranged between the fixed ring 241 and the second inner sleeve 220, and when the second inner sleeve 220 pushes the variable-diameter ball seat 242, the variable-diameter ball seat 242 contracts inwardly and is clamped on the fixed ring 241.

[0058] Preferably, the fixed ring 241 and the second electric control nipple 230 are connected through a shear pin 243.

[0059] When the soluble fracturing ball 250 is put in, the soluble fracturing ball 250 is clamped on the variable-diameter ball seat 242 and the pressure above is blocked, and when the pressure reaches a certain value, the shear pin 243 is sheared off, so that the fixed ring 241 and the second electric control nipple 230 are separated, and the second inner sleeve 220, the pressure blocking ball and the ball catcher 240 move downward together to open the fracturing hole 112.

[0060] When the electrically controlled cluster fracturing sliding sleeve according to the pressure signal opening principle is used, when the sliding sleeve needs to be opened, a pressure signal is applied through the wellhead, the pressure signal is transmitted to the first inner sleeve 120 through the liquid in the wellbore, the inner sleeve compresses the hydraulic oil in the first annular hydraulic cavity 121 under the pressure difference, thereby transmitting the pressure signal to the first small hole 132, and the pressure sensing unit 134 receives the pressure signal. When the collected pressure signal matches the pressure signal pre-written by the electric control device, the electric control device installed in the first annular cavity 131 will unlock the electromagnetic hydraulic lock, so that the piston rod protruding into the second small hole 133 is withdrawn, and the first annular hydraulic cavity 121 is no longer in a sealed state. When the well is pressurized, the first inner sleeve 120 moves under the pressure difference, and the hydraulic oil is pressed out of the second small hole 133, thereby achieving the opening of the sliding sleeve.

[0061] The construction process of the cluster electrically controlled fracturing sliding sleeve is as follows: according to the construction requirements, all the sliding sleeves are lowered into the oil and gas well along with the well completion string, such as Figure 1 The opening principle of the electrically controlled delay toe-end sliding sleeve 100 is as follows: during the deployment of the electrically controlled delay toe-end sliding sleeve 100, the first electromagnetic hydraulic lock 135 provides sufficient locking force to ensure that the electrically controlled delay toe-end sliding sleeve 100 is not opened. Figure 2 When the electrically controlled delay toe-end sliding sleeve 100 needs to be opened for full wellbore test high pressure in the oil and gas well, a pressure signal matching the pre-written pressure wave of the electrically controlled delay toe-end sliding sleeve 100 is applied through the wellhead. The first electromagnetic hydraulic lock 135 will release the locking of the first annular hydraulic cavity 121, and the first inner sleeve 120 moves under the pressure difference in the well, thereby achieving the opening of the sliding sleeve. Figure 3 .

[0062] The electrically controlled staged fracturing sliding sleeve 200 is deployed above the electrically controlled delay toe-end sliding sleeve 100, and multiple electrically controlled staged fracturing sliding sleeves 200 are arranged according to the designed staged position of the oil and gas well. In order to efficiently develop oil and gas, one or more electrically controlled cluster fracturing sliding sleeves 300 are arranged in the fracturing section between the electrically controlled staged fracturing sliding sleeves 200 as needed to achieve cluster fracturing. The opening principles of the two sliding sleeves are as follows: the opening signal of the ball catcher 240 of the first-stage electrically controlled staged sliding sleeve is the same as that of the electrically controlled toe-end sliding sleeve. When the electrically controlled toe-end sliding sleeve is opened, the second inner sleeve 220 of the first-stage electrically controlled staged sliding sleeve also moves a distance and is hung on the opening shear pin 243 to form the ball catcher 240. In this way, after the toe-end construction is completed, a soluble fracturing ball 250 is dropped from the wellhead and falls on the ball catcher 240 of the first-stage electrically controlled staged sliding sleeve to form an interlayer packer. Figure 6 .

[0063] The pressure signal is applied again in the closed wellbore to open the first stage cluster fracturing sliding sleeve, and the catcher 240 of the second stage segmented sliding sleeve opens the signal which is the same as the opening signal of the first stage cluster sliding sleeve. In the process of realizing the first stage cluster fracturing, the second inner sleeve 220 of the second stage segmented sliding sleeve also moves a distance and is hung on the opening shear pin 243 arranged thereon. The subsequent stages are operated according to the logic.

[0064] Since the catcher 240 on each sliding sleeve is opened only when the fracturing of the previous stage is completed, the passage in the wellbore is not affected, and the same diameter soluble fracturing ball 250 can be used to form the interlayer isolation during the multi-stage fracturing until the whole wellbore fracturing operation is completed. After the soluble fracturing ball 250 is dissolved for a period of time, the passage is formed in the whole wellbore, and the next operation can be performed.

[0065] Although the preferred embodiments of the present application have been described, those skilled in the art who have the basic inventive concept can make further changes and modifications to the embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and / or modifications falling within the scope of the present application, and the changes and / or modifications made to the embodiments according to the present application should be covered within the protection scope of the present application.

Claims

1. An electrically controlled cluster frac sleeve activated by a pressure signal, characterized in that, The application relates to an electrically-controlled delayed-toe-end sliding sleeve (100) which is configured to open a fracturing hole (112) according to pressure applied at a well mouth. The electrically-controlled delayed-toe-end sliding sleeve (100) comprises a first sliding sleeve body (110) which is provided with a fracturing hole (112) at the upper portion and a first inner sleeve (120) in the inner portion; a first electrically-controlled short section (130) is arranged below the first sliding sleeve body (110). The electrically-controlled cluster fracturing sliding sleeve (300) is identical in structure to the electrically-controlled delayed-toe-end sliding sleeve (100) and different in pressure required for opening the fracturing hole (112). The electrically-controlled staged fracturing sliding sleeve (200) opens a ball catcher (240) according to pressure applied at the well mouth and is connected with the ball catcher (240) and opens a fracturing hole after a soluble fracturing ball (250) is put in. The electrically-controlled delayed-toe-end sliding sleeve (100) is arranged at the lowermost end, and a plurality of the electrically-controlled staged fracturing sliding sleeves (200) are arranged above the electrically-controlled delayed-toe-end sliding sleeve (100) to divide the electrically-controlled delayed-toe-end sliding sleeve (100) into a plurality of sections, and one or more electrically-controlled cluster fracturing sliding sleeves (300) are arranged in each section. The electrically-controlled staged fracturing sliding sleeve (200) comprises a second sliding sleeve body (210) which is provided with a fracturing hole (212) at the upper portion and a second inner sleeve (220) in the inner portion; a ball catcher (240) and a second electrically-controlled short section (230) are arranged below the second sliding sleeve body (210). The second inner sleeve (220) blocks the fracturing hole (212) in the initial state, and when pressure applied at the well mouth matches pressure set by the first electrically-controlled short section (130), the second inner sleeve (220) slides downward by a first section to open the ball catcher (240), and after the soluble fracturing ball (250) is put in, the second inner sleeve (220) continues to move downward and opens the fracturing hole (212). A second annular hydraulic cavity (221) is arranged between the second sliding sleeve body (210) and the second inner sleeve (220), a second annular cavity (231) is arranged in the second electrically-controlled short section (230), and a pressure sensing unit (134), a second electromagnetic hydraulic lock (233) and a high-temperature-resistant battery are arranged in the second annular cavity. The second annular hydraulic cavity (221) is filled with hydraulic oil, the second inner sleeve (220) is blocked to be fixed, the second electromagnetic hydraulic lock (233) locks pressure in the second annular hydraulic cavity (221) in the initial state, the pressure sensing unit detects and calculates whether pressure applied at the well mouth reaches a set value, and when the set value is reached, the second electromagnetic hydraulic lock (233) unlocks the pressure in the second annular hydraulic cavity (221). Pressure required for the electrically-controlled delayed-toe-end sliding sleeve (100) to open the fracturing hole (112) is the same as pressure required for the electrically-controlled staged fracturing sliding sleeve (200) at the lowermost end to open the ball catcher (240), and pressure required for all the electrically-controlled cluster fracturing sliding sleeves (300) in each section to open the fracturing hole (112) is the same as pressure required for the electrically-controlled staged fracturing sliding sleeve (200) at the upper end of the section to open the ball catcher (240). ​ 2. The pressure signal activated electrically controlled cluster frac sleeve of claim 1, wherein, ​ 3. The electrically controlled cluster fracturing sliding sleeve opened by pressure signal according to claim 2, characterized in that, the first inner sleeve (120) blocks the fracturing hole (112) in the initial state, and slides downward when the pressure applied at the wellhead matches the pressure set by the first electrically controlled nipple (130), and opens the fracturing hole (112).

4. The pressure signal activated electrically controlled cluster frac sleeve of claim 3, wherein, a first annular hydraulic cavity (121) is arranged between the first sliding sleeve body (110) and the first inner sleeve (120), a first annular cavity (131) is arranged in the first electrically controlled nipple (130), and a pressure sensing unit (134), a first electromagnetic hydraulic lock and a high-temperature resistant battery pack are arranged in the first annular cavity (131). The first annular hydraulic cavity (121) is filled with hydraulic oil to block the first inner sleeve (120) and fix it, the first electromagnetic hydraulic lock locks the pressure in the first annular hydraulic cavity (121), and the pressure sensing unit (134) detects and calculates whether the pressure applied at the wellhead reaches the set value, and when the set value is reached, the first electromagnetic hydraulic lock unlocks the pressure in the first annular hydraulic cavity (121).

5. The pressure signal activated electrically controlled cluster frac sleeve of claim 4, wherein, The first annular cavity (131) and the first annular hydraulic cavity (121) are connected through a first small hole (132), the pressure sensing unit (134) extends into the first small hole (132) and detects the pressure in the first small hole (132) and the first annular cavity (131), thereby calculating the pressure applied at the wellhead and comparing it with the set pressure.

6. The pressure signal activated electrically controlled cluster frac sleeve of claim 5, wherein, The first annular cavity (131) and the first annular hydraulic cavity (121) are also connected through a second small hole (133), and the first electromagnetic hydraulic lock blocks the second small hole (133) when it is extended and opens the second small hole (133) when it is retracted.

7. The pressure signal activated electrically controlled cluster frac sleeve of claim 6, wherein, The second annular cavity (231) and the second annular hydraulic cavity (221) are also connected through a third small hole (232), and the second electromagnetic hydraulic lock (233) blocks the third small hole (232) when it is extended and opens the third small hole (232) when it is retracted.

8. The pressure signal activated electrically controlled cluster frac sleeve of claim 7, wherein, The ball catcher (240) comprises a fixed ring (241) and a variable-diameter ball seat (242) arranged between the fixed ring (241) and the second inner sleeve (220), and when the second inner sleeve (220) pushes the variable-diameter ball seat (242), the variable-diameter ball seat (242) contracts inwardly and is clamped on the fixed ring (241).

9. The pressure signal activated electrically controlled cluster frac sleeve of claim 8, wherein, The fixed ring (241) and the second electrically controlled nipple (230) are connected through a shear pin (243).

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