Non-Impact Electrically Controlled Downhole Cement Slurry Release Device

Abstract

A non-impact type electric control downhole cement slurry release device, comprising an upper joint, a cement cylinder, a windowing cylinder, an intermediate joint, a connecting sleeve, a piston rod, a piston head, a reduction motor, a rotating shaft, an energy storage spring, a steel ball, a ball cage, a ball seat and a lower joint. The windowing cylinder, the intermediate joint, the connecting sleeve and the lower joint are connected to form an outer housing. The piston rod is connected to the piston head, the reduction motor, the rotating shaft, the ball cage and the ball seat to form a core shaft body. The core shaft body is connected inside the outer housing by means of a steel ball connection structure. By controlling the loosening of the steel ball connection structure by the reduction motor, the core shaft body can freely fall relative to the outer housing, thereby opening the open window, pouring the cement slurry carried in the cement cylinder onto the bridge plug that has been set in the well, realizing non-impact filling, innovating the filling process method, making the filling process safe and easy to control, the process is stable and reliable. Further, by utilizing the activation cooperation of the Hall and the permanent magnet block, the pouring time node of the cement slurry can be accurately grasped, the filling effect is improved, and the operation efficiency is increased.

Description

Technical Field

[0001] The present invention relates to a downhole cement slurry release device, and more particularly to a non-impact electric control downhole cement slurry release device. Background Art

[0002] In oilfield production, due to the large differences in geological conditions such as pressure, temperature, and lithology in different formations, it is sometimes necessary to separate different oil and gas formations according to the requirements of the production process, and then perform high-pressure fracturing construction operations on different formations separately. Therefore, bridge plugs are often used in the casing for separation operations. Among them, in the fracturing operation of ultra-high-pressure oil and gas wells, in order to improve the setting effect and pressure resistance index of the bridge plug, a certain amount of cement slurry needs to be injected into the set bridge plug after setting to form a fixed plug to strengthen the fixation of the set bridge plug device. The current method for injecting cement slurry is to use a cement injection cylinder with a striker and a rupture disk installed at the bottom. The cylinder is filled with cement slurry and is lowered to the upper part of the set bridge plug by using a cable or wire. The striker at the bottom of the injection cylinder is controlled to impact the bridge plug, causing the rupture disk to crack and releasing the cement slurry to form a cement plug at the upper end of the bridge plug. However, in actual production, this impact-destruction operation mode obviously has the risk of accidents such as easily causing damage or loosening of the set bridge plug, resulting in setting failure. Moreover, the impact operation process requirements are strict, difficult to control, and have high requirements for the technical ability of operators. Not only is the operation efficiency low, but there are also safety hazards. At the same time, since the injection cylinder cannot generate a large enough impact momentum by its own gravity in highly deviated wells and water-containing oil wells, this operation mode obviously cannot be successfully completed under natural gravity conditions, so its application range is also greatly limited. Therefore, it is necessary to improve the current downhole cement slurry injection process method, research and develop a non-impact controllable downhole cement slurry release device, improve the injection operation efficiency, and enhance the safety, stability, and reliability of the injection operation. Summary of the Invention

[0003] The object of the present invention is to provide a non-impact electric control downhole cement slurry release device, innovate the cement slurry injection process method, and use wellhead power to control the release of downhole cement slurry, so as to improve the injection operation efficiency, safety, stability, and reliability.

[0004] A non-impact type electrically controlled downhole cement slurry release device, comprising: an upper joint, a cement cylinder, a window-opening cylinder, an intermediate joint, a connecting sleeve, a piston rod, a piston head, a reduction motor, a rotating shaft, an energy storage spring, a steel ball, a ball cage, a ball seat and a lower joint; the cement cylinder, the window-opening cylinder and the connecting sleeve are all circular cylinders, the upper joint and the intermediate joint respectively have through shaft holes, the upper joint, the cement cylinder, the window-opening cylinder, the intermediate joint, the connecting sleeve and the lower joint are sequentially connected in sequence to form an outer shell body, sealing members are respectively arranged between the upper joint and the cement cylinder, between the cement cylinder and the window-opening cylinder, between the intermediate joint and the connecting sleeve, and between the connecting sleeve and the lower joint, the upper end of the upper joint has a connecting structure that cooperates with a cable torpedo, and a upper pressure-bearing joint is hermetically connected to the through shaft hole on the inner side of the lower end, conducting the cable and closing the through shaft hole of the upper joint, release windows for discharging cement slurry are arranged on the window-opening cylinder along the circumference, the piston rod is hermetically fitted and inserted into the through shaft hole of the intermediate joint, can axially move relative to the intermediate joint, the upper end is placed in the window-opening cylinder, and the piston head is connected and installed at the end head, the piston head has a sealing structure that corresponds to and cooperates with the inner circumferential wall of the window-opening cylinder, the lower end is placed in the connecting sleeve and is connected to the reduction motor, the rotating shaft is connected to the power shaft of the reduction motor and can be driven to rotate by the reduction motor, the ball seat and the ball cage are coaxially sleeved in sequence in the annular space between the rotating shaft and the connecting sleeve, through steel ball accommodating holes are arranged on the circumferential side wall of the ball cage and the steel balls are fitted and inserted, corresponding to the steel ball accommodating holes, spherical embedding grooves and steel ball release grooves are respectively arranged on the inner circumferential surface of the connecting sleeve and the outer circumferential surface of the ball seat, the spherical embedding groove is a spherical groove with the same radius of curvature as the steel ball, can cooperate with the steel ball accommodating hole alone to accommodate the steel ball, and can form a steel ball fixed connection structure between the ball cage and the connecting cylinder, and the steel ball release groove cooperates with the steel ball accommodating hole to accommodate the steel ball as a whole, a connecting structure that moves relative to the ball cage driven by the rotating shaft is arranged between the ball seat and the rotating shaft, for controlling the matching state between the steel ball release groove and the steel ball accommodating hole; the energy storage spring is arranged in the connecting sleeve and sleeved on the piston rod, and the two ends respectively act on the intermediate joint and a core shaft body formed by connecting the piston rod, the piston head, the reduction motor, the rotating shaft, the ball cage and the ball seat, and can apply an axial elastic force to the core shaft body relative to the intermediate joint;In the initial assembly structure, the steel ball accommodating hole is separately matched with the spherical embedding groove, and is offset with the steel ball releasing groove. The core shaft body is limited and fixed on the outer shell through the steel ball matching connection between the ball cage and the connecting sleeve, and the piston head is kept matching and sealing with the window opening cylinder at the upper part of the release window to close the release window relative to the cement cylinder. At the same time, the energy storage spring is in a compressed energy storage state, and a downward stroke height H of the core shaft body is preset between the core shaft body and the lower joint. The stroke height H can ensure that the core shaft body is fully descended, so that the piston head can reach the position where it is connected to the window opening cylinder at the lower part of the release window. The window cylinder cooperates with the sealing state, and the release window is opened relative to the cement cylinder; when the reduction motor drives the rotating shaft to rotate, the rotating shaft drives the ball seat to move relative to the ball cage, so that the steel ball release groove and the steel ball receiving hole in the initial assembly structure are misaligned and matched with the steel ball receiving hole, and then under the action of the elastic force of the energy storage spring, the steel ball will be squeezed out of the spherical surface embedding groove, and the whole will enter and be accommodated in the matching space between the steel ball release groove and the steel ball receiving hole, thereby releasing the steel ball connection structure between the ball cage and the connecting sleeve, and the core shaft body will move downward relative to the outer shell under the action of its own gravity and the cement slurry. ;

[0005] The non-impact electrically controlled downhole cement slurry releaser is preferably configured such that the ball seat is fixedly mounted on the rotating shaft, and the steel ball release groove and the steel ball accommodating hole are arranged on the same horizontal section. When the reduction motor drives the rotating shaft to rotate, the rotating shaft drives the ball seat to rotate coaxially, so that the steel ball release groove and the steel ball accommodating hole form a corresponding fit.

[0006] The non-impact electrically controlled downhole cement slurry releaser is preferably provided with a thrust sleeve fixedly mounted on the upper part of the rotating shaft, and the ball seat is provided with a matching sleeve on the lower part, the steel ball release groove and the steel ball accommodating hole are arranged on the same axis on different horizontal sections, and at the same time, an axial pin groove limiting matching structure is provided between the ball seat and the ball cage to limit the rotation of the ball seat relative to the ball cage and guide the axial movement of the ball seat relative to the ball cage, and the lower end surface of the thrust sleeve and the upper end surface of the ball seat are mutually symmetrical and corresponding saddle-shaped curved surfaces In the initial assembly structure, the thrust sleeve and the saddle-shaped curved surface of the ball seat maintain a close contact fit with crests and troughs interlaced with each other. When the reduction motor drives the rotating shaft to rotate, the rotating shaft drives the thrust sleeve to rotate coaxially. The thrust sleeve rotates relative to the ball seat so that the saddle-shaped curved surface fit between the thrust sleeve and the ball seat can be converted to a local contact fit with corresponding supports between crests and crests, pushing the ball seat to produce downward axial movement relative to the rotating shaft, so that the steel ball release groove and the steel ball accommodating hole form a corresponding fit.

[0007] For the non-impact type electro-controlled downhole cement slurry release device described above, further preferably, a balance rod is connected to the lower end of the core shaft body. The balance rod is a circular rod body, and is hermetically fitted and extends into the central shaft hole of the lower joint to balance the axial force generated by the piston rod under the action of well fluid pressure, reduce the frictional resistance of the relative movement between the thrust sleeve and the mating surface of the ball seat, and ensure the reliability and stability of the release of the steel ball connection structure between the ball cage and the connecting sleeve driven by the reduction motor.

[0008] The non-impact type electro-controlled downhole cement slurry release device further includes: a permanent magnet block, a measurement-while-drilling circuit, an upper Hall element and a lower Hall element. The permanent magnet block is fixedly installed in the inner cavity of the outer housing. The measurement-while-drilling circuit serves as the control core of the non-impact type electro-controlled downhole cement release device, has functions such as status monitoring, motor control and two-way communication, is installed and connected into the core shaft body, and is respectively connected to the upper Hall element and the lower Hall element. The upper Hall element and the lower Hall element are correspondingly installed on the core shaft body. The relative movement of the core shaft body with respect to the outer housing can change the spatial positions of the upper Hall element and the lower Hall element relative to the permanent magnet block. When the upper Hall element or the lower Hall element is in the same horizontal plane as the permanent magnet block, the upper Hall element or the lower Hall element can be activated. The activation positions of the upper Hall element and the lower Hall element respectively correspond to the mating states of the piston head opening the release window and closing the release window with respect to the cement cylinder, that is: when the upper Hall element is activated, the measurement-while-drilling circuit can decode and identify that the release window is in the open state, and when the lower Hall element is activated, it can decode and identify that the release window is in the closed state. The measurement-while-drilling circuit can immediately re-encode the decoded release window status information and transmit it to the surface control system through a single-core cable.

[0009] The beneficial effects of the present invention are as follows: A non-impact type electro-controlled downhole cement slurry release device is provided, which adopts a brand-new process route, overcomes the disadvantages of the impact type process method in the prior art, such as being prone to damage or loosen the set packer, having strict process requirements, low operation efficiency and potential safety hazards, innovates the filling process method of downhole cement slurry, controls the release of the steel ball connection structure between the ball cage and the connecting cylinder through a reduction motor, enables the core shaft body to freely fall relative to the outer housing, opens the initially sealed release window, and pours the cement slurry carried in the cement cylinder onto the set packer. The filling process is simple, easy to control, safe and reliable, and will not cause any impact or damage to the set packer, and has the characteristics of good process stability and high operation reliability. Further, by utilizing the activation cooperation between the Hall element and the permanent magnet block, and simultaneously decoding and identifying the Hall activation signal in real time through the downhole control circuit and encoding and uploading the structural state information of the release device, it is also possible to accurately grasp the pouring time node of the cement slurry, further ensure the stability and reliability of the filling operation, improve the filling effect and increase the operation efficiency. Description of the Drawings

[0010] Figure 1 This is a diagram of the initial assembly structure of the upper part of an electrically controlled downhole cement slurry releaser described in Example 1 and Example 2.

[0011] Figure 2 for Figure 1 Cross-sectional view of the middle BB section.

[0012] Figure 3 This is a diagram of the initial assembly structure of the lower part of an electrically controlled downhole cement slurry releaser described in Example 1.

[0013] Figure 4 for Figure 3 A partial enlarged view of point Ⅰ in the middle.

[0014] Figure 5 for Figure 3 Sectional view of the AA section.

[0015] Figure 6 This is a diagram of the initial assembly structure of the lower part of an electrically controlled downhole cement slurry releaser described in Example 2.

[0016] Figure 7 for Figure 6 Cross-sectional view of the middle CC section.

[0017] Figure 8 This is a schematic diagram of the connection structure of the ball seat and the ball cage for loosening the steel ball in Example 2.

[0018] In the marked figure legends: 1 is the upper joint, 2 is the cement cylinder, 3 is the window cylinder, 4 is the middle joint, 5 is the connecting sleeve, 6 is the piston rod, 7 is the piston head, 8 is the reduction motor, 9 is the rotating shaft, 10 is the energy storage spring, 11 is the steel ball, 12 is the ball cage, 13 is the ball seat, 14 is the lower joint, 15 is the upper pressure-bearing joint, 16 is the thrust sleeve, 17 is the balance rod, 18 is the bottom nose, 19 is the pressure-bearing pin seat, 20 is the drilling circuit, 21 is the upper Hall, 22 is the lower Hall, 23 is the permanent magnet block, 24 is the circuit outer cylinder, 25 is the circuit bracket, 26 is the rope cap head, 27 is the upper screw cover, 28 is the lower screw cover, 29 is the Hall frame, 30 is the single-core plug, 31 is the upper pressure-bearing pin, 32 is the lower pressure-bearing pin, 33 is the single-core cable, 34 is the cable clamp, 35 is the release window, and 36 is the limit key pin. DETAILED DESCRIPTION

[0019] Furthermore, the technical solution claimed for protection of the present invention is described in detail in combination with specific embodiments and the accompanying drawings. Example

[0020] An electrically controlled downhole cement slurry releaser, such as Figures 1 to 5As shown in the figure, it includes: upper joint 1, cement cylinder 2, windowing cylinder 3, intermediate joint 4, connecting sleeve 5, piston rod 6, piston head 7, reduction motor 8, rotating shaft 9, energy storage spring 10, measurement-while-drilling circuit 20, upper Hall element 21, lower Hall element 22, permanent magnet block 23, steel ball 11, ball cage 12, ball seat 13, lower joint 14, pressure-bearing joint 15, bottom nose 18 and pressure-bearing pin socket 19.

[0021] The upper joint 1, the cement cylinder 2, the windowing cylinder 3, the intermediate joint 4, the connecting sleeve 5, the lower joint 14 and the bottom nose 18 are sequentially connected in order to form an outer housing. At the upper end of the through-hole on the upper joint 1, a single-core plug 30 is installed, and at the lower end, it is hermetically connected to a pressure-bearing joint 15. On the pressure-bearing joint 15, an upper pressure-bearing pin 31 and a rope cap head 26 are respectively installed and connected. On the upper circumferential surface of the windowing cylinder 3, three release windows 35 are circumferentially distributed; the piston rod 6, the piston head 7, the measurement-while-drilling circuit 20, the reduction motor 8, the rotating shaft 9, the ball seat 13, the ball cage 12 and the balance rod 17 are correspondingly connected to form a core shaft body. Among them: at the upper end of the piston rod 6 and in the inner hole of the piston head 7, the pressure-bearing pin socket 19 is hermetically connected. On the pressure-bearing pin socket 19, a lower pressure-bearing pin 32 is installed. The measurement-while-drilling circuit 20 is fixed by a circuit support 25 and installed in a circuit outer cylinder 24. The reduction motor 8 is fixedly embedded in the upper part of the inner cavity of the ball cage 12. The rotating shaft 9 is fixedly connected to the ball seat 13 and is fitted in the lower part of the inner cavity of the ball cage 12. The lower end of the circuit outer cylinder 24 is threadedly fixed to the upper end of the ball cage 12. The upper end of the circuit outer cylinder 24 is fixedly connected to the piston rod 6 through an upper screw cap 27. And the lower end of the ball cage 12 is connected to the balance rod 17 through a lower screw cap 28, so that the measurement-while-drilling circuit 20, the reduction motor 8, the rotating shaft 9 and the ball seat 13 are connected to the core shaft body through the circuit outer cylinder 24 and the ball cage 12; the core shaft body is integrally arranged in the inner cavity of the outer housing, as Figure 5As shown in the figure, four evenly distributed steel ball accommodation holes are provided on the lower circumferential section of the constant velocity joint 12. At the same horizontal section, four spherical embedding grooves and steel ball release grooves corresponding to the steel ball accommodation holes are respectively provided on the inner side surface of the connecting sleeve 5 and the outer side surface of the ball seat 13. Steel balls 11 with a diameter D that is 1.5 times the wall thickness of the constant velocity joint 12 are respectively embedded in the steel ball accommodation holes. The spherical embedding groove is a spherical groove with the same curvature radius as the steel ball 11, and the depth of the spherical embedding groove is one-third of the diameter D of the steel ball 11. In the initial assembly structure, the spherical embedding groove and the steel ball accommodation hole are arranged in corresponding cooperation, while the steel ball release groove is arranged in a 45° dislocation with the steel ball accommodation hole respectively, and the core shaft body is fixedly locked on the outer shell through the cooperation connection of the steel balls; at the same time, an energy storage spring 10 is provided between the core shaft body and the outer shell, and the connecting ends of the energy storage spring 10 are respectively supported on the intermediate joint 4 and the upper screw cap 27. In the initial assembly structure state, the energy storage spring is compressed and deformed to store elastic energy; as Figure 4 shown, the permanent magnet block 23 is installed on the intermediate joint 4, and the upper Hall 21 and the lower Hall 22 are fixedly supported by using a non-metallic Hall framework 29 and are arranged in the shaft hole of the piston rod 6. In the initial assembly structure, the lower Hall 22 and the permanent magnet block 23 are in corresponding cooperation; a single-core cable 33 is connected between the upper pressure-bearing pin 31 and the lower pressure-bearing pin 32, and both ends of the single-core cable 33 are respectively clamped and fixed by cable clamps 34 arranged in the cable cap head 26 and the piston head 7. The single-core plug 30 and the upper pressure-bearing pin 31, the lower pressure-bearing pin 32 and the upper Hall 21, the lower Hall 22 and the measurement-while-drilling circuit 20, and between the measurement-while-drilling circuit 20 and the reduction motor 8 are interconnected by wires, so that the upper Hall 21, the lower Hall 22, the measurement-while-drilling circuit 20 and the measurement-while-drilling circuit 20 are connected to the wellhead power supply.

[0022] When applied to downhole operations, first assemble the electric control downhole cement slurry release device into an initial assembly structure and connect it to the lower end of a single-core logging cable. At the same time, connect the supporting ground control system to the logging vehicle ground cable, adjust the output voltage of the ground control system according to the length of the cable used to offset the voltage drop generated by cable transmission, ensure the adaptability of the downhole working end voltage, power on and start the ground control system, conduct a ground test on the electric control downhole cement slurry release device and confirm that the release window is in a closed state; then, fill the cement cylinder 2 with cement slurry, send the electric control downhole cement slurry release device into the well while keeping it powered off, turn on the power after reaching the operation position, the coiled tubing circuit 20 starts and begins to decode and identify the activation states of the upper Hall 21 and the lower Hall 22 in real time, and the decoded information is encoded and then transmitted to the ground control system to reflect the functional structure state of the cement slurry release device. When it is detected that the lower Hall 22 is activated and it is determined that the release window 35 is in a closed state, the ground control system can be used to start the reduction motor 8, the reduction motor 8 drives the ball seat 13 to rotate through the rotating shaft 9. When the ball seat 13 rotates 45° relative to the ball cage 12, the steel ball release grooves on the ball seat 13 respectively form corresponding fits with the steel ball accommodation holes on the ball cage 12. At this time, under the elastic force of the energy storage spring 10, the steel balls 12 will be extruded from the spherical embedding grooves on the connecting sleeve 5 and enter the steel ball release grooves, which can loosen the steel ball locking connection between the ball cage 12 and the connecting sleeve 5. The core shaft body moves downward relative to the outer casing under the action of its own gravity and the gravity of the cement slurry it bears. After passing through the stroke height H, the piston head 7 moves to the lower part of the release window 35, opening the release window 35. Then, the cement slurry filled in the cement cylinder 2 will pour out and be filled in the downhole set packer plug; when the upper Hall 21 moves downward with the core shaft body to a position corresponding to the permanent magnet block 23, the upper Hall 21 is activated, the coiled tubing circuit 20 immediately decodes, identifies and encodes and uploads it to the ground control system. After confirming that the release window 35 is already in a fully open state, the downhole power supply can be interrupted, and the single-core cable is pulled to lift the electric control downhole cement release device to the ground to complete the cement slurry filling operation. Example

[0023] An electric control downhole cement slurry release device, such as Figure 1 , Figure 2 , Figure 6 , Figure 7 and Figure 8As shown in the figure, it includes: upper sub 1, cement cylinder 2, windowing cylinder 3, intermediate sub 4, connecting sleeve 5, piston rod 6, piston head 7, reduction motor 8, rotating shaft 9, energy storage spring 10, logging-while-drilling circuit 20, upper Hall element 21, lower Hall element 22, permanent magnet block 23, steel ball 11, ball cage 12, ball seat 13, lower sub 14, thrust sleeve 16, balance rod 17, bottom nose 18 and lower pressure-bearing sub 19.

[0024] The upper joint 1, the cement cylinder 2, the window cylinder 3, the middle joint 4, the connecting sleeve 5, the lower joint 14 and the bottom nose 18 are sequentially connected to form an outer shell with the same structure as that of Example 1; the piston rod 6, the piston head 7, the drilling circuit 20, the reduction motor 8, the rotating shaft 9, the ball seat 13, the ball cage 12, the thrust sleeve 16 and the balance rod 17 are correspondingly connected to form a core shaft body, wherein: the pressure-bearing pin seat 19 is sealed and connected to the upper end of the piston rod 6, and the lower pressure-bearing pin 32 is installed on the pressure-bearing pin seat 19, and the drilling circuit 20 The circuit bracket 25 is used to fix the circuit and install it in the circuit outer cylinder 24. The reduction motor 8 is fixedly embedded in the upper part of the inner cavity of the ball cage 12. The rotating shaft 9 is fixedly connected with the thrust sleeve 16 and is sleeved with the ball seat 13. The matching device is in the lower part of the inner cavity of the ball cage 12. An axial keyway is provided on the rotating shaft 9. At the same time, a limiting key pin 36 that cooperates with the axial keyway is provided on the ball seat 13. The limiting key pin 36 is embedded in the axial keyway, so that an axial limiting matching connection is established between the ball seat 13 and the rotating shaft 9, limiting the rotation of the ball seat 13 relative to the rotating shaft 9. , but keep the ball seat 13 axially movable relative to the rotating shaft 9, the lower end surface of the thrust sleeve 16 and the upper end surface of the ball seat 13 are corresponding saddle-shaped curved surfaces, and in the initial assembly structure, the corresponding saddle-shaped curved surfaces maintain a close contact and fit with crests and troughs interlaced with each other, the lower end of the circuit outer cylinder 24 is threadedly fixedly connected to the upper end of the ball cage 12, the upper end of the circuit outer cylinder 24 is fixedly connected to the piston rod 6 through an upper screw cover 27, and the lower end of the ball cage 12 is connected to the balance rod 17 through a lower screw cover 28, so that the drilling circuit 20, the reduction motor 8, and the rotating shaft 9 are connected to each other. The shaft 9, the thrust sleeve 16 and the ball seat 13 are connected to the mandrel body by means of the circuit outer tube 24 and the ball cage 12; the mandrel body is integrally arranged in the inner cavity of the outer shell, and four evenly distributed steel ball receiving holes are provided on the lower circumferential section of the ball cage 12. At the same time, on the same horizontal section, the inner side surface of the connecting sleeve 5 is provided with four spherical surface setting grooves corresponding to the steel ball receiving holes, and on different horizontal sections, the outer side surface of the ball seat 13 is provided with four axially corresponding steel ball releasing grooves, and the steel ball receiving holes are respectively provided with a diameter D of 1.Five times the number of the steel balls 11, the spherical embedding groove is a spherical groove with the same radius of curvature as the steel balls 11, and the depth of the groove is one-third of the diameter D of the steel balls 11. In the initial assembly structure, the spherical embedding groove is correspondingly arranged in cooperation with the steel ball accommodating hole, while the steel ball release groove is axially misaligned with the steel ball accommodating hole respectively, and the core shaft body is fixedly locked on the outer casing through the connection and cooperation of the steel balls. At the same time, an energy storage spring 10 is arranged between the core shaft body and the outer casing, and both ends of the energy storage spring 10 are respectively supported on the intermediate joint 4 and the upper screw cap 27 and are compressed and store energy in the initial assembly structure; in addition, this embodiment also has the same connection and installation structure of the permanent magnet block 23, the upper Hall 21 and the lower Hall 22 as in Embodiment 1, and realizes supplying wellhead power to the upper Hall 21, the lower Hall 22, the measurement-while-drilling circuit 20 and the measurement-while-drilling circuit 20 through the same circuit connection system.

[0025] During downhole operation, the production operation procedures and methods of the electro-controlled downhole cement release device in this embodiment are exactly the same as those in Embodiment 1, and the main difference in its working principle is that: after the ground control system starts the reduction motor 8, the reduction motor 8 drives the thrust sleeve 16 to rotate through the rotating shaft 9. Since the thrust sleeve 16 and the ball seat 13 are in a saddle-shaped surface fit, the rotation of the thrust sleeve 16 relative to the ball seat 13 will push the ball seat 13 to move axially downward relative to the rotating shaft 9. When the thrust sleeve 16 rotates 90°, a support contact fit with the wave peaks corresponding to each other will be formed between the saddle-shaped surfaces of the thrust sleeve 16 and the ball seat 13. At this time, the steel ball release grooves on the ball seat 13 respectively form corresponding fits with the steel ball accommodating holes on the ball cage 12. Similarly, under the action of the elastic force of the energy storage spring 10, the steel balls 12 are extruded from the spherical embedding grooves on the connecting sleeve 5 into the steel ball release grooves, so that the locking connection of the steel balls between the ball cage 12 and the connecting sleeve 5 is loosened, and the core shaft body moves downward relative to the outer casing, opening the release window 35 until the cement slurry filling operation is completed.

Claims

1. A non-impact type electric control downhole cement slurry release device, characterized in that, Comprising: Upper joint (1), cement cylinder (2), windowing cylinder (3), intermediate joint (4), connecting sleeve (5), piston rod (6), piston head (7), reduction motor (8), rotating shaft (9), energy storage spring (10), steel ball (11), ball cage (12), ball seat (13) and lower joint (14); The cement cylinder (2), the windowing cylinder (3) and the connecting sleeve (5) are all circular cylinders. The upper joint (1) and the intermediate joint (4) respectively have through shaft holes. The upper joint (1), the cement cylinder (2), the windowing cylinder (3), the intermediate joint (4), the connecting sleeve (5) and the lower joint (14) are sequentially connected in sequence to form an outer shell. Sealing members are respectively arranged between the upper joint (1) and the cement cylinder (2), between the cement cylinder (2) and the windowing cylinder (3), between the intermediate joint (4) and the connecting sleeve (5), and between the connecting sleeve (5) and the lower joint (14). An upper pressure-bearing joint (15) is hermetically connected to the through shaft hole on the inner side of the lower end of the upper joint (1). Release windows (35) distributed along the circumference are provided on the windowing cylinder (3). The piston rod (6) is hermetically fitted and inserted into the through shaft hole of the intermediate joint (4), and can axially move relative to the intermediate joint (4). The upper end is placed in the windowing cylinder (3), and the piston head (7) is connected and installed at the end head. The piston head (7) has a sealing structure corresponding to and mating with the inner circumferential wall of the windowing cylinder (3). The lower end is placed in the connecting sleeve (5) and is connected to the reduction motor (8). The rotating shaft (9) is connected to the power shaft of the reduction motor (8). The ball seat (13) and the ball cage (12) are coaxially sleeved and arranged in sequence in the annular space between the rotating shaft (9) and the connecting sleeve (5). Through steel ball accommodation holes are provided on the circumferential side wall of the ball cage (12) and the steel balls (11) are arranged in cooperation. Corresponding to the steel ball accommodation holes, spherical embedding grooves and steel ball release grooves are respectively provided on the inner circumferential surface of the connecting sleeve (5) and the outer circumferential surface of the ball seat (13). The spherical embedding groove is a spherical groove with the same radius of curvature as the steel ball (11). A connecting structure is provided between the ball seat (13) and the rotating shaft (9) that is driven by the rotating shaft (9) to move relative to the ball cage (12); The energy storage spring (10) is arranged in the connecting sleeve (5) and sleeved on the piston rod (6), and acts on the intermediate joint (4) and the core shaft body formed by connecting the piston rod (6), the piston head (7), the reduction motor (8), the rotating shaft (9), the ball cage (12) and the ball seat (13) at both ends respectively. In the initial assembly structure, the steel ball accommodating hole and the spherical surface inlay groove are arranged in a separate cooperation, and are offset from the steel ball release groove. Through the steel ball fitting connection between the ball cage (12) and the connecting sleeve (5), the core shaft body is limited and fixed on the outer shell body, and the piston head (7) is kept in sealing cooperation with the windowing cylinder (3) at the upper part of the release window. At the same time, the energy storage spring (10) is in a compressed energy storage state. A downward travel height H of the core shaft body is preset between the core shaft body and the lower joint (14). The travel height H can ensure that the core shaft body travels downward sufficiently, so that the piston head (7) can reach the state of sealing cooperation with the windowing cylinder (3) at the lower part of the release window.

2. The non-impact type electric control downhole cement slurry release device according to claim 1, characterized in that: The ball seat (13) is fixedly sleeved on the rotating shaft (9), and the steel ball release groove and the steel ball accommodating hole are arranged in the same horizontal section.

3. The non-impact type electric control downhole cement slurry release device according to claim 1, characterized in that: A thrust sleeve (16) is fixedly sleeved on the upper part of the rotating shaft (9), and the ball seat (13) is sleeved in a matching manner on the lower part. The steel ball release groove and the steel ball accommodating hole are arranged on the same axis in different horizontal sections. At the same time, an axial pin groove limiting and matching structure is arranged between the ball seat (13) and the ball cage (12) to limit the rotation of the ball seat (13) relative to the ball cage (12) and guide the axial movement of the ball seat (13) relative to the ball cage (12). The lower end surface of the thrust sleeve (16) and the upper end surface of the ball seat (13) are mutually symmetric and corresponding saddle-shaped curved surfaces. In the initial assembly structure, the saddle-shaped curved surfaces between the thrust sleeve (16) and the ball seat (13) are kept in a close contact and matching state with the wave peaks and wave valleys staggered. When the reduction motor (8) drives the rotating shaft (9) to rotate, the rotating shaft (9) drives the thrust sleeve (16) to rotate coaxially. The relative rotation of the thrust sleeve (16) with respect to the ball seat (13) can make the matching of the saddle-shaped curved surfaces between it and the ball seat (13) transition to a partial contact and matching state with the wave peaks corresponding to each other.

4. The non-impact type electric control downhole cement slurry release device according to claim 3, wherein: A balance rod (17) is connected to the lower end of the core shaft body. The balance rod (17) is a circular rod body and is hermetically and fittingly extended into the central shaft hole of the lower joint (14).

5. The non-impact type electric control downhole cement slurry release device according to any one of claims 1 to 4, characterized in that, It further includes: a permanent magnet block (23), a measurement-while-drilling circuit (20), an upper Hall element (21) and a lower Hall element (22); The permanent magnet block (23) is fixedly installed in the inner cavity of the outer housing. The logging-while-drilling circuit (20) is connected into the mandrel body and is respectively connected to the upper Hall element (21) and the lower Hall element (22). The upper Hall element (21) and the lower Hall element (22) are correspondingly installed on the mandrel body. The relative movement of the mandrel body with respect to the outer housing can change the spatial positions of the upper Hall element (21) and the lower Hall element (22) relative to the permanent magnet block (23). When the upper Hall element (21) or the lower Hall element (22) is in the same horizontal plane as the permanent magnet block (23), the upper Hall element (21) or the lower Hall element (22) can be activated. The activation positions of the upper Hall element (21) and the lower Hall element (22) respectively correspond to the mating states of the piston head (7) opening the release window (35) and closing the release window (35) relative to the cement cylinder (2).

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