Geothermal well broken layer well cementation device

Abstract

The utility model relates to the technical field of geothermal well cementation, and discloses a geothermal well broken layer cementation device which comprises a short section, a connecting rod and a connecting rod. A blind plate is fixedly connected with the bottom end of the short section, a grouting hole communicated with the short section is formed in the blind plate, a plurality of blocking plates are hinged to the upper surface of the blind plate, and a circle is defined by the outer edges of the blocking plates; and the driving mechanism is used for limiting and adjusting the overturning angle of the plugging plate. Compared with a traditional steel wire rope control scheme, in the working process of the fixing device, the driving mechanism can achieve the overturning angle of the plugging plate and can achieve the limiting effect of a specific angle at the same time so as to meet different working scenes, a closed space can be formed below the plugging plate, and the slurry leakage phenomenon in the later period can be avoided.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of geothermal well cementing, particularly to a geothermal well broken layer cementing device. BACKGROUND

[0002] As a clean and renewable energy, geothermal resources are increasingly valued. During the drilling process of geothermal wells, broken formations are often encountered, which pose many challenges to cementing operations. Due to the unstable rock structure of broken layers, problems such as collapse and loss are prone to occur. Traditional cementing devices are difficult to form a stable and well-sealed cementing structure in broken layers, which makes it difficult to ensure the quality of cementing and affects the subsequent performance of geothermal wells, such as the efficiency of geothermal fluid extraction, the stability of the well wall, and the service life of the geothermal well.

[0003] Patent No. CN215889962U discloses a geothermal well cementing plugging device. During use, the steel plate is stretched upwards by the second pull ring and steel wire rope until the first rubber layer is attached to the well wall, forming an initial friction force. Then, by continuing to lower the drill pipe, the steel plate is fully expanded, further forming a sealed space between the plugging plate and the well bottom. Then, cement slurry is injected to achieve the plugging process.

[0004] However, the above-mentioned patent still has the following defects during use: since the plugging plate and the steel plate are both located at the well bottom, it is difficult to determine whether the steel plate is stretched in place during the upward stretching process, and it is also difficult to determine the degree of expansion of the steel plate during the further lowering of the drill pipe. The sealing performance is difficult to guarantee, which leads to the phenomenon of slurry leakage in the sealed space in the later stage.

[0005] Therefore, how to improve the sealing performance of the existing cementing device has become a technical problem that needs to be solved by those skilled in the art. UTILITY MODEL CONTENTS

[0006] The utility model aims at providing a geothermal well broken layer cementing device to overcome the above-mentioned shortcomings.

[0007] In order to achieve the above-mentioned purpose, the technical scheme of the utility model is as follows: a geothermal well broken layer cementing device, comprising:

[0008] a short section at the top end for detachable connection with a drill pipe;

[0009] a blind plate fixedly connected to the bottom end of the short section, a grouting hole communicated with the short section being arranged on the blind plate, and a plurality of plugging plates being hingedly connected to the upper surface of the blind plate, the outer edges of the plurality of plugging plates being enclosed into a circular shape; and

[0010] a driving mechanism for limiting and adjusting the overturning angle of the plugging plates.

[0011] Further, the driving mechanism comprises:

[0012] A threaded pipe rotatably connected to the short section;

[0013] A driving ring threadedly connected to the threaded pipe;

[0014] A plurality of connecting rods, one end of each of the connecting rods being hingedly connected to the sealing plate, and the other end of each of the connecting rods being hingedly connected to the driving ring; and

[0015] A driving assembly for driving the threaded pipe to rotate.

[0016] Further, the driving assembly comprises:

[0017] A first gear coaxially and fixedly connected to the bottom end of the threaded pipe;

[0018] A second gear rotatably connected to the upper surface of the blind plate and in meshing transmission with the first gear; and

[0019] A driving motor in transmission connection with the second gear.

[0020] Further, the driving mechanism further comprises:

[0021] A sealing housing covering the threaded pipe, the first gear and the second gear, the bottom end of the sealing housing being fixedly connected to the upper surface of the blind plate, the top end of the sealing housing being slidably connected to the outer sidewall of the short section, the sidewall of the sealing housing being provided with a plurality of sliding holes arranged in the vertical direction, and each of the connecting rods being movably and penetratingly arranged through each of the sliding holes, and the driving ring being slidably connected to the inner sidewall of the sealing housing in the vertical direction.

[0022] Further, the outer sidewall of the driving ring is a polygonal prism, and the inner sidewall of the sealing housing is a polygonal prism matched with the outer sidewall of the driving ring.

[0023] Further, the driving motor is fixedly connected to the outer side of the sealing housing, the output shaft of the driving motor penetrating the sealing housing and being in spline connection with the second gear, and the driving motor being a stepping motor or a servo motor.

[0024] Further, the transmission ratio of the first gear and the second gear is greater than 1.

[0025] Further, a rubber plate is fixedly connected to the outer edge of the sealing plate.

[0026] Further, an inner thread is arranged on the inner sidewall of the top end of the short section.

[0027] Compared with the prior art, the utility model has at least the following advantages:

[0028] Compared with the traditional steel wire rope control scheme, in the working process of the fixing device, the driving mechanism can realize the overturning angle of the plugging plate and can realize the limiting effect of a specific angle, so as to meet different working scenes, so that the space below the plugging plate can realize airtightness, and the phenomenon of slurry leakage in the later period is avoided. BRIEF DESCRIPTION OF DRAWINGS

[0029] In order to more clearly illustrate the technical scheme in the embodiments of the present application or the prior art, the drawings needed in the embodiments will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0030] Figure 1 It is a whole structure schematic view of the geothermal well broken layer well cementing device of the present application.

[0031] Figure 2 It is a sectional view of the geothermal well broken layer well cementing device of the present application.

[0032] Figure 3 It is another sectional view of the geothermal well broken layer well cementing device of the present application.

[0033] Figure 4 It is a local enlarged view of the A area in the present application. Figure 3

[0034] Reference signs: 1, short section; 2, blind plate; 3, grouting hole; 4, plugging plate; 5, threaded pipe; 6, driving ring; 7, connecting rod; 8, first gear; 9, second gear; 10, driving motor; 11, sealing shell; 12, sliding hole; 13, rubber plate; 14, internal thread; 15, bearing; 16, sealing ring. DETAILED DESCRIPTION

[0035] The technical scheme in the embodiments of the present application will be described clearly and completely in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only some embodiments of the present application, not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0036] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the present application will be further described in detail in combination with the drawings and specific embodiments.

[0037] Reference Figures 1-4 ​The utility model provides a kind of geothermal well broken layer cementing device, for the broken layer of geothermal well is carried out cementing plugging, specific structure includes nipple 1, blind plate 2, plugging plate 4 and driving mechanism.The top end of nipple 1 is used to be detachably connected with drill pipe (not shown in drawing), and the inner side wall of nipple 1 is provided with internal thread 14, and the bottom end of drill pipe is provided with external thread, and the top end of nipple 1 and the bottom end of drill pipe are detachably connected by thread, and one-way valve (not shown in drawing) is arranged in nipple 1, for realizing that cement slurry passes from top to bottom, prevent forming backflow.Blind plate 2 is fixedly connected with the bottom end of nipple 1, and the both are usually welded in fixed mode, and blind plate 2 is cylindrical plate, and the diameter of blind plate 2 is less than the inner diameter of geothermal well, and grouting hole 3 in communication with nipple 1 is arranged on blind plate 2, and cement slurry can sequentially pass through drill pipe, nipple 1 and grouting hole 3 etc. component to realize the work of grouting below blind plate 2.A plurality of plugging plate 4 is hinged on the upper surface of blind plate 2, and the number is not less than three.These plugging plate 4 are used to block the gap between blind plate 2 and geothermal well, and the outer edge is enclosed into circle;Driving mechanism is used to limit the angle of plugging plate 4, and driving mechanism can realize the limiting of specific angle while adjusting the angle of plugging plate 4.

[0038] In use, first, connect drill pipe on the top end of nipple 1, and use driving mechanism to turn plugging plate 4 upward, so that plugging plate 4 has no contact with the inner wall of geothermal well;Second, use drill pipe to lower the utility model cementing device above broken layer;Third, use driving mechanism to drive plugging plate 4 to turn downward, so that it is parallel to blind plate 2, at this time, plugging plate 4 can abut on the inner wall of geothermal well, and then grouting work is carried out;Finally, when cement slurry is cured, use driving mechanism to drive plugging plate 4 to turn upward again, so that plugging plate 4 has no contact with the inner wall of geothermal well, and the utility model cementing device is lifted through drill pipe, and the connection between drill pipe and nipple 1 can be released.

[0039] Compared with the traditional steel wire rope control scheme, in the working process of the utility model fixing device, driving mechanism can realize the angle of plugging plate 4, and can realize the limiting effect of specific angle, to meet different working scenes, so that the space below plugging plate 4 can realize airtight, avoid slurry leakage phenomenon in later period.

[0040] Preferably, the driving mechanism comprises the threaded pipe 5, the driving ring 6, the connecting rod 7 and the driving assembly. Wherein, the inner ring of the plurality of bearings 15 is fixedly connected to the circumferential side of the short section 1, the outer ring of the bearings 15 is fixedly connected with the threaded pipe 5, the threaded pipe 5 is rotatably connected to the circumferential side of the short section 1; the driving ring 6 is threadedly connected to the circumferential side of the threaded pipe 5; the connecting rod 7 is equal in number to the blanking plate 4, one end of the connecting rod 7 is hingedly connected to the blanking plate 4 in one-to-one correspondence, the other end of the connecting rod 7 is hingedly connected to the driving ring 6; the driving assembly is used to drive the threaded pipe 5 to rotate, in the process of driving the threaded pipe 5 to rotate by the driving assembly, the other end of the connecting rod 7 can be respectively raised and lowered, thereby driving the blanking plate 4 to be raised and lowered, so as to realize the process that the blanking plate 4 is respectively stored above the blind plate 2 or abuts against the upper surface of the blind plate 2.

[0041] Specifically, the driving assembly comprises the first gear 8, the second gear 9 and the driving motor 10. Wherein, the first gear 8 is coaxially fixedly connected to the bottom end of the threaded pipe 5, the second gear 9 is rotatably connected to the upper surface of the blind plate 2 and is in meshing transmission with the first gear 8, the transmission ratio of the first gear 8 and the second gear 9 is greater than 1, so as to realize the effect of speed reduction and torque increase, the driving motor 10 is in transmission connection with the second gear 9, the driving motor 10 is a stepping motor or a servo motor, and is electrically connected with a control unit (not shown in the figure), the control unit can be selected as a PLC device, and the control unit is electrically connected with an external power supply (not shown in the figure), such as a storage battery.

[0042] The control unit controls the driving motor 10 to start and stop, so as to selectively drive the first gear 8 and the second gear 9 to rotate, thereby realizing the rotating process of the threaded pipe 5.

[0043] In order to reduce the dust interference of the surrounding soil and optimize the working environment of the threaded pipe 5, the first gear 8 and the second gear 9 as much as possible, the driving mechanism of the utility model further comprises a sealing shell 11, the sealing shell 11 covers the circumferential side of the threaded pipe 5, the first gear 8 and the second gear 9, the bottom end of the sealing shell 11 is fixedly connected with the upper surface of the blind plate 2, the top end of the sealing shell 11 is slidably connected with the outer side wall of the short section 1, the top end of the sealing shell 11 is provided with a sealing ring 16, the top end of the sealing shell 11 is in interference fit with the outer side wall of the short section 1 through the sealing ring 16, the side wall of the sealing shell 11 is provided with a plurality of sliding holes 12 arranged in the vertical direction, a plurality of connecting rods 7 are movably and correspondingly arranged through the plurality of sliding holes 12, and the driving ring 6 is slidably connected with the inner side wall of the sealing shell 11 in the vertical direction. The driving ring 6 is slidably connected with the inner side wall of the sealing shell 11 in the vertical direction. The outer side wall of the driving ring 6 is a polygonal prism, and the inner side wall of the sealing shell 11 is adapted thereto. This design can effectively prevent the driving ring 6 from rotating synchronously with the threaded pipe 5, so that the threaded pipe 5 can only slide up and down along the axial direction, thereby improving the operability of the device. The driving motor 10 is fixedly connected to the outer side of the sealing shell 11, the output shaft of the driving motor 10 penetrates the sealing shell 11 and is in spline connection with the second gear 9.

[0044] In order to improve the sealing between the outer edge of the sealing plate 4 and the inner wall of the geothermal well, the sealing plate 4 is fixedly connected with a rubber plate 13.

[0045] The working principle of the utility model is as follows:

[0046] Firstly, the bottom end of the drill pipe is threadedly connected with the top end of the short section 1, the driving motor 10 is rotated to move the driving ring 6 upward, and then the sealing plate 4 is flipped to the upper side of the blind plate 2.

[0047] Secondly, the well cementing device is lowered into the geothermal well by the drill pipe, and the sealing plate 4 does not contact the inner wall of the geothermal well during the lowering process until the well cementing device is lowered to a position 30-50 m above the broken layer.

[0048] Thirdly, the driving motor 10 is rotated to move the driving ring 6 downward, the sealing plate 4 is flipped to the upper surface of the blind plate 2 and is attached to the blind plate 2, and at the same time, the rubber plate 13 is attached to the inner wall of the geothermal well, and at this time, the blind plate 2, the sealing plate 4 and the bottom of the well form a closed space.

[0049] Fourthly, the cement pump (not shown in the figure) on the ground is used to pour the cement slurry into the closed space formed between the blind plate 2 and the bottom of the well through the annulus of the drill pipe, and when the cement fills the closed space, the cement pump on the ground is used, when the pressure of the cement pump reaches 2-3 times of the formation pressure between the sealing section and the ground surface, the pressure is kept constant, and the cement is fully infiltrated into the formation along the broken layer.

[0050] Fifthly, after the cement is poured under pressure, the cement in the annulus of the drill pipe is replaced with clean water, and after the cement in the closed space is initially cured for 4-8 hours, the driving motor 10 is rotated to move the driving ring 6 upward, so that the sealing plate 4 does not contact the inner wall of the geothermal well, and then the well cementing device is lifted to the ground by the drill pipe.

[0051] Sixthly, after the cement is fully condensed and solidified, the whole sealing operation is completed, and the secondary condensation time is 40-44 hours, and then the drill tool for sweeping the cement plug can be lowered and the normal drilling construction process can be entered.

[0052] In the description of the utility model, it should be understood that the orientation or positional relationship indicated by the terms "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the utility model, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, therefore it cannot be understood as a limitation on the utility model.

[0053] The above-described embodiments are merely preferred modes of the present application, and are not intended to limit the scope of the present application. Various modifications and improvements to the technical solutions of the present application made by those of ordinary skill in the art without departing from the design spirit of the present application shall fall within the scope of protection of the present application as defined by the claims.

Claims

1. A device for cementing a fractured zone of a geothermal well, characterized in that, The utility model relates to a short joint (1) for detachable connection with a drill rod, a blind plate (2) fixedly connected to the bottom end of the short joint (1), a grouting hole (3) provided on the blind plate (2) and communicating with the short joint (1), a plurality of sealing plates (4) hingedly connected to the upper surface of the blind plate (2), the outer edges of the sealing plates (4) being circularly arranged, a driving mechanism for limiting and adjusting the turning angle of the sealing plates (4), and a driving assembly for driving the threaded tube (5) to rotate. The driving mechanism comprises a threaded tube (5) rotatably connected to the lateral side of the short joint (1), a driving ring (6) threadedly connected to the lateral side of the threaded tube (5), a plurality of connecting rods (7), one end of each of the connecting rods (7) being hingedly connected to one of the sealing plates (4), the other end of each of the connecting rods (7) being hingedly connected to the driving ring (6), and a driving assembly for driving the threaded tube (5) to rotate. The driving assembly comprises a first gear (8) coaxially and fixedly connected to the bottom end of the threaded tube (5), a second gear (9) rotatably connected to the upper surface of the blind plate (2) and in meshing transmission with the first gear (8), and a driving motor (10) in transmission connection with the second gear (9). The driving mechanism further comprises a sealing housing (11) covering the threaded tube (5), the first gear (8) and the second gear (9), the bottom end of the sealing housing (11) being fixedly connected to the upper surface of the blind plate (2), the top end of the sealing housing (11) being slidably connected to the outer lateral wall of the short joint (1), the lateral wall of the sealing housing (11) being provided with a plurality of sliding holes (12) arranged in the vertical direction, each of the connecting rods (7) being movably and penetratingly arranged in one of the sliding holes (12), and the driving ring (6) being slidably connected to the inner lateral wall of the sealing housing (11) in the vertical direction.

2. The geothermal well fracture packer of claim 1, wherein, The outer lateral wall of the driving ring (6) is in the shape of a polygonal prism, and the inner lateral wall of the sealing housing (11) is in the shape of a polygonal prism matching the outer lateral wall of the driving ring (6). The driving motor (10) is fixedly connected to the outer side of the sealing housing (11), the output shaft of the driving motor (10) penetrating the sealing housing (11) and being in spline connection with the second gear (9), and the driving motor (10) is a stepping motor or a servo motor. The transmission ratio of the first gear (8) and the second gear (9) is greater than 1. The outer edge of the sealing plate (4) is fixedly connected with a rubber plate (13). The inner lateral wall of the top end of the short joint (1) is provided with an internal thread (14).

3. The geothermal well fracture packer of claim 2, wherein, ​ ​ ​ ​ 4. The geothermal well fracture packer of claim 3, wherein, ​ ​ 5. The geothermal well fracture packer of claim 4, wherein, ​ 6. The geothermal well fracture packer of claim 5, wherein, ​ 7. The apparatus of claim 3, wherein, ​ 8. The geothermal well fracture packer of claim 1, wherein, ​ 9. The geothermal well fracturing zone cementing apparatus of claim 1, wherein, ​

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