Grading cementing device

Abstract

The invention discloses a graded cementing device, which belongs to the technical field of oil and gas exploitation, and comprises a shell, a top interface, a bottom interface, a bevel gear ring, a closing plug seat, a secondary outlet, a closing plug and an opening plug, the bevel gear ring bearing is connected to the top of the shell, a plurality of circulating inner holes are formed in the bevel gear ring bearing, a fixing ring is fixedly connected to the position outside the bevel gear ring, a plurality of circulating outer holes are formed in the fixing ring, and the circulating outer holes and the circulating inner holes are alternately staggered and / or overlapped; a plurality of first-stage outlets are formed in the closing plug seat, and sealing blocks are arranged in the second-stage outlets and can reciprocate in the second-stage outlets; and the closing plug and the opening plug are respectively used for closing the primary outlet and opening the secondary outlet. The device has the advantages that through the design, opening and closing of the first-stage outlet and the second-stage outlet can be stably achieved, and dislocation of the circulating inner hole and the circulating outer hole can be conveniently adjusted.

Description

Technical Field

[0001] The invention relates to the technical field of oil and gas exploitation, and in particular to a staged cementing device. Background Art

[0002] In cementing operations for long casing strings or complex well conditions where one-time cementing cannot meet the requirements, the well sections with different formation pressure systems can be effectively sealed by means of staged cementing, reducing problems such as oil, gas and water migration caused by cement slurry weight loss. In this process, a staged cementing device is needed.

[0003] On the staged cementing device, the primary outlet, secondary outlet and circulation port play different roles in cementing operations. In the first stage of cementing, cement slurry flows out from the primary outlet, enters the annulus between the casing and the well wall, and seals the lower well section. For example, in deep well cementing, cement slurry is first injected into a well section at a certain depth through the primary outlet to achieve preliminary sealing of this part of the formation. When the primary cementing operation is completed and the conditions for secondary cementing are met, cement slurry flows out from the secondary outlet to seal the well section above the primary cementing section, completing the entire process of staged cementing. Before and after the cementing operation, the circulation port can be used as a circulation channel for fluids such as drilling fluid.

[0004] However, in the prior art, the secondary outlet and circulation port of the staged cementing device are mostly opened or closed by holding pressure and mechanical shearing. The defect of the mechanical shearing method is that the opening and closing of the port is not stable enough. If the shearing fails, the switch failure will occur. The defect of the holding pressure switch is that if the static pressure difference between the inside and outside of the pipe is large, the closing pressure will be too high, which increases the difficulty of closing, and the downward resistance of the closing sleeve or the opening sleeve will increase, affecting the efficiency of the switch.

[0005] There is currently a lack of a device that can solve the above problems. Summary of the invention

[0006] The invention provides a graded cementing device, which is used to solve the defects of the prior art that the switch port is unstable and the switch efficiency is affected.

[0007] The present invention provides a graded cementing device, comprising: an outer shell, the outer shell is in a cylindrical shape that penetrates from top to bottom; a top interface and a bottom interface, the top interface is arranged above the outer shell, the bottom interface is arranged below the outer shell, and the peripheries of the top interface and the bottom interface away from the outer shell are both provided with threads for connecting a casing; a bevel gear ring, the bevel gear ring bearing is connected to the top of the outer shell and is located between the outer shell and the top interface, the outer diameter of the bevel gear ring is smaller than the outer diameter of the outer shell, the bevel gear ring is provided with a plurality of circulation inner holes, the top of the outer shell is fixedly connected to a fixing ring outside the bevel gear ring, the fixing ring is provided with a plurality of circulation outer holes, The inner circulation hole and the outer circulation hole are alternately staggered and / or overlapped; a closing plug seat is arranged at the junction of the bottom interface and the outer shell, and a plurality of primary outlets are arranged on the closing plug seat for discharging primary cement; a secondary outlet is arranged at the bottom side edge of the outer shell and is located above the closing plug seat, and a sealing block is arranged in the secondary outlet for sealing the secondary outlet, and the sealing block can reciprocate in the secondary outlet, and a channel is arranged on the sealing block for discharging secondary cement; a closing plug and an opening plug, which can be moved in the graded cement injector, and are respectively used to close the primary outlet and open the secondary outlet.

[0008] Optionally, the bevel gear ring is provided with a plurality of bevel gears meshing with it, and a tooth plate meshing with it is provided on one side of each of the bevel gears, and a tooth groove for accommodating the tooth plate is provided on the top of the shell, and the tooth plate is located in the tooth groove and reciprocates up and down, and the tooth plate and the opening plug are made of materials with magnetic adsorption capabilities, and when the opening plug descends in the shell, it passes through the tooth plate, and the tooth plate is brought down by magnetic adsorption, thereby engaging the bevel gear to rotate, and a plurality of cavities are provided at the bottom of the top interface, and the cavities are used to accommodate the movement of the bevel gears and the tooth plates, and a plug shaft is inserted into the bevel gear, and the plug shaft is fixedly connected to the inner wall of the cavity.

[0009] Optionally, the bottom of the tooth plate and the bottom wall of the tooth groove are interconnected by means of a spring three, a rotating plate is rotatably connected to the bottom wall of the tooth groove, a clamping column is inserted into the top of the rotating plate, a clamping groove is provided at the lower part of the tooth plate, and the clamping column moves in the clamping groove as the tooth plate reciprocates up and down to limit the tooth plate.

[0010] Optionally, the clamping groove is provided with corners one, two, three, four, five and six in sequence, and when the clamping column is located in corner one, the tooth plate is located at the top, and when the clamping column is located in corner four, the tooth plate is located at the bottom.

[0011] Optionally, the opening plug is arranged in an annular shape, and a plurality of push holes are opened on its outer circumference. A spring 1 is fixedly connected in the push hole, and a push plate is fixedly connected on the spring 1. Leakage holes are opened on both sides of the push hole, and the leakage holes extend into the annular inner diameter of the opening plug and penetrate it.

[0012] Optionally, the sealing block has an inner opening on one side facing the inner side of the shell, which is practically matched with the leak hole, and the top of the sealing block has a top opening on the part facing the outer side of the shell, and the top opening and the inner opening are interconnected.

[0013] Optionally, slideways are provided on both sides of the interior of the sealing block and the secondary outlet, a channel is formed between the sealing block and the slideways on the secondary outlet, a sliding column is fixedly connected in the channel, a sliding block is slidably connected to the sliding column, the sliding block is fixedly connected in the slideway of the sealing block, and both ends of the sliding block and the sliding column are interconnected by a second spring.

[0014] Optionally, a plurality of plugs are fixedly connected to the bottom of the closing plug, and the plugs are used in conjunction with the primary outlet. When the plugs are inserted into the primary outlet, the primary outlet is sealed.

[0015] Optionally, a plurality of slide rails are provided on the closing plug and the opening plug, and the inner walls of the outer shell, the top interface and the bottom interface are fixedly connected with slide bars used in conjunction with the slide rails, and the slide rails slide on the slide bars to prevent the opening plug and / or the closing plug from being displaced.

[0016] Optionally, no slide bar is provided at the level where the fixing ring is located, and the height of the fixing ring is lower than the length of the opening plug and / or the closing plug.

[0017] A graded cementing device provided by the present invention can drive the inner circulation hole and the outer circulation hole to alternate with each other to achieve opening and closing by driving the conical gear ring to rotate. At the same time, the opening plug can achieve the opening of the secondary outlet by pushing the sealing block inside the secondary outlet. Compared with the prior art, the graded cementing device described in the present invention adopts a mechanical structure to achieve a more stable opening and closing port, thereby solving the problems of unstable opening and low efficiency in the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 The overall three-dimensional structure of the present invention Figure 1; Figure 2 It is a partial three-dimensional structure of the present invention Figure 1 ; Figure 3 It is the overall front cross-sectional view of the present invention; Figure 4 The overall three-dimensional structure of the present invention Figure 2 ; Figure 5 It is a partial three-dimensional structure of the present invention Figure 2 ; Figure 6 is a three-dimensional structural diagram of the opening plug of the present invention; Figure 7 is a top cross-sectional view of an opening plug of the present invention; Figure 8 is a three-dimensional structural diagram of the closing plug of the present invention; Fig. 9 It is a three-dimensional structural diagram of the sealing block of the present invention; Fig.10 is a side cross-sectional view of a sealing block of the present invention; Fig.11 is a side cross-sectional view of the rack and tooth groove of the present invention; Fig.12 is an enlarged cross-sectional view of the clamping slot of the present invention; Fig.13 It is an enlarged view of A of the present invention; Fig.14 It is an enlarged view of B of the present invention; Fig.15 It is an enlarged view of point C of the present invention.

[0020] Reference numerals: 1. Shell; 2. Top interface; 3. Bottom interface; 4. Conical gear ring; 5. Circulation inner hole; 6. Fixed ring; 7. Circulation outer hole; 8. Closing plug seat; 9. Primary outlet; 10. Secondary outlet; 11. Sealing block; 12. Closing plug; 13. Opening plug; 14. Bevel gear; 15. Tooth plate; 16. Tooth groove; 17. Receptacle; 18. Insert shaft; 19. Spring three; 20. Rotating plate; 21. Snap-on column; 22. Snap-on groove; 23. Angle one; 24. Angle two; 25. Angle three; 26. Angle four; 27. Angle five; 28. Angle six; 29. ​​Push hole; 30. Spring one; 31. Push plate; 32. Leakage hole; 33. Inner opening; 34. Top opening; 35. Slideway; 36. Sliding column; 37. Sliding block; 38. Spring two; 39. Plug block; 40. Slide rail; 41. Slide bar. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0022] As mentioned above, in the prior art, the secondary outlet and circulation port of the staged cementing device are mostly opened or closed by holding pressure and mechanical shearing. The defect of the mechanical shearing method is that the opening and closing of the port is not stable enough. If the shearing fails, the switch failure will occur. The defect of the holding pressure switch is that if the static pressure difference between the inside and outside of the pipe is large, the closing pressure will be too high, which increases the difficulty of closing, and the downward resistance of the closing sleeve or the opening sleeve will increase, affecting the efficiency of the switch.

[0023] In view of this, the present invention provides a staged cementing device, which solves the problem of unstable switch ports and low efficiency in the prior art. The present invention is implemented in the following manner: like Figure 1-Figure 15 As shown, the staged cementing device of the present invention mainly includes a shell 1, a top interface 2, a bottom interface 3, a bevel gear ring 4, a closing plug seat 8, a secondary outlet 10, a closing plug 12 and an opening plug 13, wherein the shell 1 is in a cylindrical configuration that passes through from top to bottom, the top interface 2 is disposed above the shell 1, and the bottom interface 3 is disposed below the shell 1, and the peripheries of the top interface 2 and the bottom interface 3 that are away from the shell 1 are both provided with threads for connecting the casing. The bevel gear ring 4 is bearing-connected to the top of the shell 1 and is located between the shell 1 and the top interface 2, as shown in FIG. Figure 5 As shown, the outer diameter of the bevel gear ring 4 is smaller than the outer diameter of the outer shell 1, which reserves some space for the top of the outer shell 1. A number of circulation inner holes 5 are provided on the bevel gear ring 4, and a fixing ring 6 is fixedly connected to the reserved space. A number of circulation outer holes 7 are provided on the fixing ring 6. Since the bevel gear ring 4 is connected to the top of the outer shell 1 by a bearing, it can rotate compared with the bevel gear ring 4. When it rotates, the circulation inner hole 5 will rotate with the bevel gear ring 4, thereby achieving the technical effect of alternating misalignment and / or overlap between the circulation inner hole 5 and the circulation outer hole 7. When the circulation inner hole 5 and the circulation outer hole 7 are misaligned, the inside and outside of the outer shell 1 are sealed as a whole, and various levels of cement can be paid attention to. When the circulation inner hole 5 and the circulation outer hole 7 overlap, the inside of the outer shell 1 is connected to the outside through the overlapping holes, thereby achieving its use effect.

[0024] The closing plug seat 8 is arranged at the junction of the bottom interface 3 and the outer shell 1. A plurality of first-level outlets 9 are arranged on the closing plug seat 8 for discharging first-level cement. When the first-level cement is filled and solidified, the closing plug 12 can be inserted from the top of the top interface 2. Under the action of gravity and pump pressure, the closing plug 12 passes through the top interface 2, the outer shell 1, and the bottom interface 3 in sequence, and finally sits on the closing plug seat 8 to close the first-level outlet 9.

[0025] The secondary outlet 10 is arranged at the bottom side edge of the shell 1. There are several secondary outlets 10 and they are located above the closing plug seat 8. A sealing block 11 is arranged in the secondary outlet 10 for sealing the secondary outlet 10. The sealing block 11 can reciprocate in the secondary outlet 10. When the secondary outlet 10 is sealed, the sealing block 11 is completely located on the inner wall of the secondary outlet 10. When the sealing block 11 is pushed, it is misaligned with the secondary outlet 10. A channel is arranged on the sealing block 11. When it is misaligned, the channel is used to discharge the secondary cement. When it needs to be opened, the opening plug 13 can be inserted into the closing plug 12 from the top of the top interface 2. Under the action of gravity and pump pressure, the closing plug 12 falls through the top interface 2, the shell 1 and the bottom interface 3 in sequence, and sits on the closing plug 12. At this time, the sealing block 11 is pushed by the opening plug 13, and the secondary outlet 10 is misaligned. The channel connects the internal environment of the shell 1 with the external environment, which can be used to fill the secondary cement.

[0026] Therefore, in the embodiment provided by the present invention, by driving the bevel gear ring 4 to rotate, the circulation inner hole 5 and the circulation outer hole 7 can be driven to alternate with each other to achieve opening and closing. At the same time, the opening plug 13 can achieve the opening of the secondary outlet 10 by pushing the sealing block 11 inside the secondary outlet 10. Compared with the prior art, the graded cementing device described in the present invention adopts a mechanical structure to achieve a more stable opening and closing port, thereby solving the problems of unstable opening and closing port and low efficiency in the prior art.

[0027] In order to further clearly and completely explain the operating principle of the staged cementing device of the present invention, the present invention also provides another preferred embodiment, as shown in FIG. Figure 5 As shown, in another preferred embodiment of the present invention, in order to drive the rotation of the bevel gear ring 4, the present invention is provided with a plurality of bevel gears 14 meshing with it on the bevel gear ring 4, and a tooth plate 15 meshing with it is provided on one side of each bevel gear 14. When the tooth plate 15 falls, since the tooth plate 15 and the bevel gear 14 are meshing, the bevel gear 14 rotates accordingly, driving the bevel gear ring 4 to rotate, the tooth plate 15 drops to the bottom, and the bevel gear 14 rotates one cycle. At this time, the circulating inner hole 5 and the circulating outer hole 7 overlap to form a through hole, and when the tooth plate 15 rises to the highest point, the circulating inner hole 5 and the circulating outer hole 7 are misaligned, thereby achieving sealing. Of course, the reverse is also true.

[0028] In order to accommodate the movement of the tooth plate 15, the present invention further provides a tooth groove 16 for accommodating the tooth plate 15 at the top of the shell 1, the tooth plate 15 is located in the tooth groove 16 and reciprocates up and down, the tooth plate 15 and the opening plug 13 are both made of materials with magnetic adsorption capabilities (when it is necessary to drive the tooth plate 15 to move, an opening plug 13 made of a material with magnetic adsorption capabilities can be used, and when it is not necessary to drive the tooth plate 15 to move, an opening plug 13 made of a conventional material can be used), when the opening plug 13 descends in the shell 1, it passes through the tooth plate 15, and the tooth plate 15 is brought down by magnetic adsorption, and then the meshing bevel gear 14 is rotated, and the opening plug 13 continues to descend until it is separated from the magnetic attraction of the tooth plate 15. At this time, the tooth plate 15 stays in the tooth groove 16. If it is to be reset, another opening plug 13 can be put in, so that the circulating inner hole 5 and the circulating outer hole 7 can be repeatedly overlapped or misaligned. At the same time, a plurality of cavities 17 are provided at the bottom of the top interface 2 . The cavities 17 are used to accommodate the movement of the bevel gear 14 and the toothed plate 15 . The bevel gear 14 is plugged with an insertion shaft 18 , which is fixedly connected to the inner wall of the cavity 17 .

[0029] In order to achieve the above technical effect of the tooth plate 15 staying in the tooth groove 16, as shown in FIG. Figure 11-Figure 12 As shown, in another preferred embodiment of the present invention, the bottom of the tooth plate 15 and the bottom wall of the tooth groove 16 are connected to each other by a spring 3 19, a rotating plate 20 is rotatably connected to the bottom wall of the tooth groove 16, a clamping column 21 is inserted on the top of the rotating plate 20, a clamping groove 22 is provided at the lower part of the tooth plate 15, and the clamping column 21 moves in the clamping groove 22 with the up and down reciprocating movement of the tooth plate 15 to limit the tooth plate 15. Specifically, the clamping groove 22 is provided with a corner 1 23, a corner 24, a corner 3 25, a corner 4 26, a corner 5 27 and a corner 6 28 in sequence, when the clamping column 21 is located in the corner 1 23, the tooth plate 15 is located at the top, and when the clamping column 21 is located in the corner 4 26, the tooth plate 15 is located at the bottom.

[0030] Therefore, another preferred embodiment of the present invention is implemented in detail. Fig.11 Take the state of the middle tooth plate 15 as an example. Fig.11In the figure, the tooth plate 15 is at the highest point, and the clamping column 21 is located in the corner 1 23. When the tooth plate 15 moves downward, the clamping column 21 moves in the clamping groove 22, moves toward the direction of the corner 6 28 or the corner 2 24, and changes the movement trajectory at the corner 5 27 or the corner 3 25, and finally stops at the corner 4 26. At this time, the tooth plate 15 moves downward and is located at the lowest point. The function of the spring 3 19 is to ensure the reset of the tooth plate 15. Due to the easy deformation of the spring 3 19, in order to ensure that it can smoothly drive the tooth plate 15 to reset, a damper or positioning rod can be added to the spring 3 19 during the specific implementation. Since this method is common knowledge in the art, its technical principle will not be repeated here. The same applies to the following springs. When the tooth plate 15 needs to be reset, it is only necessary to drive the tooth plate 15 to move downward a certain distance, so that the clamping column 21 disengages from the angle four 26, and moves in the opposite direction along the trajectory of the above-mentioned angles, and finally resets under the push of the spring three 19 and falls back into the angle one 23. At this time, the tooth plate 15 reaches the top, and through the above-mentioned method, the tooth plate 15 is driven to engage the bevel gear 15 to drive the bevel gear ring 4 to reciprocate, thereby driving the overlapping or misalignment of the circulating inner hole 5 and the circulating outer hole 7.

[0031] In another preferred embodiment of the present invention, the opening plug 13 is arranged in an annular shape, and a plurality of push holes 29 are provided on its outer peripheral surface, a spring 30 (whose anti-deformation effect is the same as that of the spring 19) is fixedly connected in the push hole 29, a push plate 31 is fixedly connected on the spring 30, and leak holes 32 are provided on both sides of the push hole 29, and the leak holes 32 extend into the inner diameter of the annular opening plug 13 and are connected therewith. At the same time, an inner opening 33 which is practically matched with the leak hole 32 is provided on the side of the sealing block 11 facing the inner side of the housing 1, and a top opening 34 is provided on the top of the sealing block 11 facing the outer side of the housing 1, and the top opening 34 and the inner opening 33 are connected to each other. Slideways 35 are provided on both sides of the sealing block 11 and the secondary outlet 10. A channel is formed between the sealing block 11 and the slideways 35 on the secondary outlet 10. A slide post 36 is fixedly connected in the channel. A slider 37 is slidably connected to the slide post 36. The slider 37 is fixedly connected in the slideway 35 of the sealing block 11. Both ends of the slider 37 and the slide post 36 are connected to each other by a spring 38.

[0032] Therefore, when another preferred embodiment of the present invention is implemented, the plug 13 is opened and descended, and the push plate 31 is pushed by the inner walls of the outer shell 1, the top interface 2, and the bottom interface 3, and is always in the push hole 29. The spring 1 30 also shrinks to the limit. When it falls to the sealing block 11, the push plate 31 loses its push limit force, and then escapes from the push hole 29, and pushes the sealing block 11, so that it is misaligned with the secondary outlet 10. At this time, the top through port 34 on the sealing block 11 is connected to the external environment, and at the same time, the inner through port 33 is connected to the leakage hole 32 on the push plate 31, thereby forming a connecting environment from the external environment to the top through port 34 to the inner through port 33 to the leakage hole 32 to the push plate 31. At this time, the secondary cement is injected into the casing, and the secondary cement enters the external environment from the above-mentioned connecting environment, and the injection is finally completed.

[0033] In order to prevent the secondary cement from being confused with the primary cement when it is injected, Figure 8 As shown, in a preferred embodiment of the present invention, a plurality of plugs 39 are fixedly connected to the bottom of the closing plug 12. The plugs 39 are used in conjunction with the primary outlet 9. When the plugs 39 are inserted into the primary outlet 9, the primary outlet 9 is sealed. This isolates the primary cement from the secondary cement. At the same time, in order to ensure that the closing plug 12 and the opening plug 13 can remain stable and not rotate when falling in the grading column cementer, so as to successfully complete the docking of the above-mentioned components, as shown in FIG. Figure 1 , Figure 6 , Figure 8 As shown, in a preferred embodiment of the present invention, a plurality of slide rails 40 are provided on the closing plug 12 and the opening plug 13, and the inner walls of the housing 1, the top interface 2 and the bottom interface 3 are fixedly connected with slide bars 41 used in conjunction with the slide rails 40, and the slide rails 40 slide on the slide bars 41 to prevent the opening plug 13 and / or the closing plug 12 from being displaced, thereby ensuring the smooth docking of the above components. In order to ensure the smooth docking of the circulation inner hole 5 and the circulation outer hole 7, the above slide bars 41 are segmented, that is, there are no slide bars within the height of the fixing ring 6, therefore, in order to ensure that the opening plug 13 or the closing plug 12 is not stuck when displaced, the height of the fixing ring 6 is set to be lower than the length of the opening plug 13 and / or the closing plug 12.

[0034] In summary, another preferred embodiment provided by the present invention is to open the plug 13 to drop the magnetic tooth plate 15 to move, so as to drive the bevel gear ring 4 to rotate, and finally drive the inner circulation hole 5 and the outer circulation hole 7 to overlap or misalign, so as to realize the opening or closing of the circulation hole. In this way, the advantage is that the opening or closing of the circulation hole is not one-time, but can be used multiple times, and the stability of the switch is also guaranteed, which has stronger stability than the existing technology. At the same time, the present invention also realizes the opening and closing of the secondary outlet 10 by pushing the sealing block 11 with the push plate 31 on the open plug 13. This method has stronger stability than the pressure opening method in the prior art, can improve the operating efficiency of the graded cementing device, and finally complete the cement cementing operation in the field of oil and gas production.

[0035] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A staged cementing device, characterized in that: include: A housing (1), wherein the housing (1) is in the shape of a cylinder that penetrates from top to bottom; A top interface (2) and a bottom interface (3), wherein the top interface (2) is arranged above the outer shell (1), and the bottom interface (3) is arranged below the outer shell (1), and threads are arranged on the peripheries of the ends of the top interface (2) and the bottom interface (3) away from the outer shell (1) for connecting with a sleeve; A bevel gear ring (4), wherein the bevel gear ring (4) is bearing-connected to the top of the housing (1) and is located between the housing (1) and the top interface (2); the outer diameter of the bevel gear ring (4) is smaller than the outer diameter of the housing (1); a plurality of circulation inner holes (5) are provided on the bevel gear ring (4); a fixing ring (6) is fixedly connected to the top of the housing (1) outside the bevel gear ring (4); a plurality of circulation outer holes (7) are provided on the fixing ring (6); and the circulation inner holes (5) and the circulation outer holes (7) are alternately staggered and / or overlapped; A closing plug seat (8) is arranged at the junction of the bottom interface (3) and the outer shell (1), and a plurality of primary outlets (9) are arranged on the closing plug seat (8) for discharging primary cement; A secondary outlet (10) is arranged at the bottom side edge of the housing (1) and is located above the closing plug seat (8). A sealing block (11) is arranged in the secondary outlet (10) for sealing the secondary outlet (10). The sealing block (11) can reciprocate in the secondary outlet (10). A channel is arranged on the sealing block (11) for discharging secondary cement. A closing plug (12) and an opening plug (13), wherein the closing plug (12) and the opening plug (13) can be moved in the staged cementing device and are used to close the primary outlet and open the secondary outlet respectively.

2. The staged cementing device according to claim 1, characterized in that: The bevel gear ring (4) is provided with a plurality of bevel gears (14) meshing therewith, and a tooth plate (15) meshing therewith is provided on one side of each bevel gear (14). A tooth groove (16) for accommodating the tooth plate (15) is provided at the top of the housing (1). The tooth plate (15) is located in the tooth groove (16) and reciprocates up and down. The tooth plate (15) and the opening plug (13) are both made of a material with magnetic adsorption capability. When the opening plug (13) descends in the housing (1), it passes through the tooth plate (15), and the tooth plate (15) is pulled down by magnetic adsorption, thereby meshing with the bevel gear (14) and rotating. A plurality of cavities (17) are provided at the bottom of the top interface (2). The cavities (17) are used to accommodate the movement of the bevel gear (14) and the tooth plate (15). An insertion shaft (18) is inserted into the bevel gear (14), and the insertion shaft (18) is fixedly connected to the inner wall of the cavity (17).

3. The staged cementing device according to claim 2, characterized in that: The bottom of the tooth plate (15) and the bottom wall of the tooth groove (16) are connected to each other by means of a spring three (19); a rotating plate (20) is rotatably connected to the bottom wall of the tooth groove (16); a clamping column (21) is inserted into the top of the rotating plate (20); a clamping groove (22) is provided at the bottom of the tooth plate (15); the clamping column (21) moves in the clamping groove (22) as the tooth plate (15) reciprocates up and down, thereby limiting the position of the tooth plate (15).

4. The staged cementing device according to claim 3, characterized in that: The clamping groove (22) is provided with corners 1 (23), 2 (24), 3 (25), 4 (26), 5 (27) and 6 (28) in sequence. When the clamping column (21) is located in corner 1 (23), the tooth plate (15) is located at the top, and when the clamping column (21) is located in corner 4 (26), the tooth plate (15) is located at the bottom.

5. The staged cementing device according to claim 1, characterized in that: The opening plug (13) is arranged in an annular shape, and a plurality of push holes (29) are provided on its outer circumference. A spring (30) is fixedly connected inside the push hole (29), and a push plate (31) is fixedly connected to the spring (30). Leak holes (32) are provided on both sides of the push hole (29), and the leak holes (32) extend into the annular inner diameter of the opening plug (13) and are communicated with the annular inner diameter.

6. The staged cementing device according to claim 5, characterized in that: The sealing block (11) has an inner opening (33) on one side facing the inner side of the housing (1) and is practically matched with the leak hole (32). The top of the sealing block (11) has a top opening (34) on the part facing the outer side of the housing (1). The top opening (34) and the inner opening (33) are interconnected.

7. The staged cementing device according to claim 1, characterized in that: Slideways (35) are provided on both sides of the sealing block (11) and the secondary outlet (10). A channel is formed between the sealing block (11) and the slideways (35) on the secondary outlet (10). A slide post (36) is fixedly connected in the channel. A slider (37) is slidably connected to the slider (36). The slider (37) is fixedly connected in the slideway (35) of the sealing block (11). Both ends of the slider (37) and the slider (36) are connected to each other via a second spring (38).

8. The staged cementing device according to claim 1, characterized in that: A plurality of plug blocks (39) are fixedly connected to the bottom of the closing plug (12). The plug blocks (39) are used in conjunction with the primary outlet (9). When the plug blocks (39) are inserted into the primary outlet (9), the primary outlet (9) is sealed.

9. The staged cementing device according to claim 1, characterized in that: The closing plug (12) and the opening plug (13) are both provided with a plurality of slide rails (40); the inner walls of the housing (1), the top interface (2) and the bottom interface (3) are all fixedly connected with slide bars (41) used in conjunction with the slide rails (40); the slide rails (40) slide on the slide bars (41) to prevent the opening plug (13) and / or the closing plug (12) from being displaced.

10. The staged cementing device according to claim 9, characterized in that: The level where the fixing ring (6) is located is not provided with a slide bar (41), and the height of the fixing ring (6) is lower than the length of the opening plug (13) and / or the closing plug (12).

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