Casing centralizing and extracting device in deep geothermal well

Abstract

The utility model discloses a deep geothermal well inner sleeve centralizing and extracting device which comprises a centralizing and extracting body and a universal hanging ring, the centralizing and extracting body is arranged in an inner sleeve to conduct centralizing and auxiliary extracting, a centralizing and extracting clamping jaw used for being connected with the inner sleeve in a clamping mode is arranged on the surface of the centralizing and extracting body, and the universal hanging ring is arranged on the surface of the centralizing and extracting body. At least two centralizing and extracting clamping jaws are arranged in the circumferential direction of the centralizing and extracting body, and the centralizing and extracting clamping jaws are installed on the centralizing and extracting body in a swinging mode and can retract into the centralizing and extracting body or stretch out of the centralizing and extracting body; the universal hanging ring is installed at the top end of the centralizing and extracting body and used for hanging and dragging the centralizing and extracting body. The device is simple in structure, convenient to operate, good in practicability and well suitable for underwater operation of the deep well, and the problems that an inner sleeve is blocked and difficult to extract at present are effectively solved.

Description

Technical Field

[0001] The utility model relates to the technical field of heat exchange of deep geothermal wells, in particular to a casing straightening and extraction device in a deep geothermal well. Background Art

[0002] As a renewable energy source, geothermal energy has the advantages of wide distribution, low cost, easy mining, cleanliness and direct utilization. Vigorously promoting the use of geothermal energy is an effective measure for resource conservation and environmental protection, and is a way to achieve sustainable development of human society. At present, geothermal energy utilization technology is constantly developing and has become the best choice for building heating and cooling. The current geothermal technology is to drill holes in the rock and soil layer generally 2000m to 3000m underground, insert an inner casing into the wall of the geothermal well pipe, and under the action of the heat exchanger, cold water enters deep into the geothermal well pipe wall, absorbs the underground high-temperature heat, and then flows upward from the bottom of the inner casing with thermal insulation, guiding the underground high-temperature heat to the heat exchanger, and heating the building through the heat exchanger. The principle can be found in Fig.10 .

[0003] The inner casing is prone to getting stuck when it is out of the well. The main reasons for the jam are: since the well depth can reach 2000m and geothermal wells are generally inclined wells, in order to ensure that the inner casing is smoothly lowered into the well, a counterweight structure is generally added to the bottom of the inner casing. When the inner casing is out of the well, the friction between the inner casing and the pipe wall causes jamming, or the friction between the counterweight structure and the pipe wall causes jamming, resulting in the inner casing being unable to be smoothly out of the well. Utility Model Content

[0004] The technical problem to be solved by the utility model is to provide a casing straightening and extracting device for a deep geothermal well which has a simple structure, is easy to use and can smoothly assist in extracting the casing from the well.

[0005] In order to solve the above technical problems, the technical solution of the utility model is: a casing straightening and extraction device in a deep geothermal well, comprising:

[0006] The righting and extracting body is used to be placed in the inner casing for righting and auxiliary extraction. The surface of the righting and extracting body is provided with righting and extracting claws for clamping with the inner casing. At least two righting and extracting claws are arranged along the circumference of the righting and extracting body. The righting and extracting claws are swingably mounted on the righting and extracting body and can be retracted into the righting and extracting body or extended out of the righting and extracting body.

[0007] A universal lifting ring is installed on the top of the uprighting and extracting body and is used for lifting the uprighting and extracting body.

[0008] As a preferred technical solution, at least two claw accommodating grooves are arranged on the outer peripheral surface of the straightening and extraction body, the number of the claw accommodating grooves corresponds one to one to the number of the straightening and extraction claws, the lower part of the straightening and extraction claw is connected to the lower part of the claw accommodating groove by a rotating shaft, and the upper part of the straightening and extraction claw can be swung out of the claw accommodating groove or swung back into the claw accommodating groove.

[0009] As a preferred technical solution, the straightening and extracting claw is eccentrically mounted on the rotating shaft, and the straightening and extracting claw swings outward by its own weight and extends to abut against the bottom end surface of the claw accommodating groove.

[0010] As a preferred technical solution, both ends of the rotating shaft are respectively welded to the straightening and extraction body, and the straightening and extraction claws are rotatably mounted on the rotating shaft.

[0011] As a preferred technical solution, a cone is provided at the lower portion of the uprighting and extracting body, and the cone is formed by shrinking downward from the bottom end of the uprighting and extracting body.

[0012] As a preferred technical solution, the outer peripheral surface of the straightening and extraction body is also provided with a spiral structure.

[0013] As a preferred technical solution, the spiral structure is a spiral groove arranged on the outer surface of the straightening and extraction body.

[0014] As a preferred technical solution, a connecting head is fixed to the top of the straightening and extraction body, and the universal lifting ring is installed on the connecting head.

[0015] As a preferred technical solution, the universal lifting ring is a lifting ring screw with 360° universal rotation, and the lifting ring screw is threadedly installed on the connecting head.

[0016] As a preferred technical solution, the wall surface of the inner sleeve is arranged with a righting and extraction groove corresponding to the righting and extraction claw. When the righting and extraction claw corresponds to the position of the righting and extraction groove, the righting and extraction claw swings outward and extends into the righting and extraction groove.

[0017] Due to the adoption of the above technical scheme, the beneficial effects of the utility model are as follows: when the righting and extracting claw is constrained by the inner casing wall inside the inner casing, the righting and extracting claw retracts into the righting and extracting body, and the righting and extracting device can move downward along the inner casing wall; when the righting and extracting claw is not constrained by the inner casing wall, the righting and extracting claw extends out of the righting and extracting body and extends into the righting and extracting slot, the righting and extracting claw can be engaged with the inner casing, and at this time, the righting and extracting device is dragged upward to give the inner casing an upward force, so that the inner casing is righted and the inner casing is assisted to be extracted upward and smoothly out of the well. The utility model has a simple structure, is easy to operate, and has good practicality. It is well suited for underwater operations in such deep wells, and effectively solves the current problems of inner casing jamming and difficulty in extraction. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The following drawings are only intended to illustrate and explain the present invention, and are not intended to limit the scope of the present invention.

[0019] Figure 1 It is a structural schematic diagram of the righting and extracting device of the embodiment of the utility model;

[0020] Figure 2 This is a front sectional view of the righting and extracting device according to an embodiment of the utility model;

[0021] Figure 3 It is a side view of the righting and extracting device of the embodiment of the utility model;

[0022] Figure 4 This is a schematic diagram of the structure of the inner sleeve in an embodiment of the utility model;

[0023] Figure 5 This is a structural principle diagram of the main viewing angle when the embodiment of the utility model is righting;

[0024] Figure 6 yes Figure 5 The enlarged schematic diagram of point A in the middle;

[0025] Figure 7 This is a schematic diagram of the structure of the embodiment of the utility model when viewed from a top view when righting;

[0026] Figure 8 This is a structural principle diagram of the main viewing angle after the embodiment of the utility model is straightened;

[0027] Fig. 9 This is a schematic diagram of the structure of the embodiment of the utility model when viewed from a top view after being straightened;

[0028] Fig.10 It is a schematic diagram of the heat exchange principle of a deep geothermal well in the background technology;

[0029] In the figure: 1-universal lifting ring; 2-connecting head; 3-rightening and extracting body; 4-conical body; 5-rightening and extracting claw; 6-claw receiving groove; 7-rotating shaft; 8-shoulder structure; 9-spiral groove; 10-inner casing; 11-rightening and extracting groove; 12-geothermal well pipe wall. DETAILED DESCRIPTION

[0030] The present invention is further described below in conjunction with the accompanying drawings and examples. In the following detailed description, only certain exemplary embodiments of the present invention are described by way of illustration. Needless to say, those skilled in the art will recognize that the described embodiments may be modified in various ways without departing from the spirit and scope of the present invention. Therefore, the drawings and descriptions are illustrative in nature and are not intended to limit the scope of protection of the claims.

[0031] The inner casing straightening and extraction device for a deep geothermal well has an overall circumferential dimension smaller than the inner diameter of the inner casing 10, can be placed inside the inner casing 10 and used in conjunction with the inner casing 10 to achieve straightening of the inner casing 10 and assist in the upward extraction of the inner casing to smoothly exit the well.

[0032] like Figures 1 to 3 As shown, the casing straightening and extraction device for a deep geothermal well comprises a universal lifting ring 1, a connector 2, a straightening and extraction body 3 and a cone 4 which are arranged in sequence from top to bottom. The connector 2 is used as a connector between the universal lifting ring 1 and the straightening and extraction body 3. The universal lifting ring 1 is installed on the connector 2 at the top of the straightening and extraction body 3. The universal lifting ring 1 is used to connect a high-strength fiber rope to pull the straightening and extraction body 3, pull the device upward, straighten the inner casing and assist the inner casing to be extracted upward; the cone 4 is located at the lower part of the straightening and extraction body 3, and its cone structure enables the straightening and extraction device to overcome the resistance in the water and sink downward.

[0033] In this embodiment, the uprighting and extracting body 3 and the conical body 4 are an integrally formed metal solid structure, so that the uprighting and extracting device has a certain weight and can sink downward along the inner wall of the inner sleeve 10 by its own gravity.

[0034] See also Figures 1 to 3The straightening and extraction body 3 is a key component of the straightening and extraction device. The surface of the straightening and extraction body 3 is arranged with a straightening and extraction claw 5 for clamping with the inner sleeve 10. The straightening and extraction claw 5 is a key component for realizing the straightening function. There are three straightening and extraction claws 5 evenly distributed along the circumference of the straightening and extraction body 3. The straightening and extraction claw 5 is swingably installed on the straightening and extraction body 3 and can be retracted into the straightening and extraction body 3 or extended out of the straightening and extraction body 3. The wall surface of the inner sleeve 10 is arranged with a straightening and extraction groove 11 corresponding to the straightening and extraction claw 5. When the position of the straightening and extraction claw 5 corresponds to the straightening and extraction groove 11, the straightening and extraction claw 5 swings outward and extends into the straightening and extraction groove 11. When the righting and extraction claw 5 is constrained by the wall of the inner casing 10 inside the inner casing 10, the righting and extraction claw 5 retracts into the righting and extraction body 3, and the righting and extraction device can move downward along the wall of the inner casing 10; when the righting and extraction claw 5 is not constrained by the wall of the inner casing 10, the righting and extraction claw 5 extends out of the righting and extraction body 3 and extends into the righting and extraction slot 11, the righting and extraction claw 5 can be engaged with the inner casing 10, and the righting and extraction device is dragged upward at this time, giving the inner casing 10 an upward force, so that the inner casing 10 is righted and assisted in the extraction of the inner casing.

[0035] The upper surface of the outer end of the straightening and extracting claw 5 is inclined so that the outer end of the straightening and extracting claw forms a pointed end, which is convenient for cooperation with the straightening and extracting groove 11 of the inner casing.

[0036] In this embodiment, the inner sleeve 10 is a cylindrical tube, the straightening and extraction body 3 is a cylinder, the outer diameter of the straightening and extraction body 3 is smaller than the inner diameter of the inner sleeve 10, and when all the straightening and extraction claws 5 are retracted, the entire device can slide along the inner sleeve 10.

[0037] In this embodiment, three claw accommodating grooves 6 are arranged on the outer peripheral surface of the righting and extracting body 3, and the number of the claw accommodating grooves 6 corresponds to the number of the righting and extracting claws 5. The lower part of the righting and extracting claw 5 is connected to the lower part of the claw accommodating groove 6 through the rotating shaft 7, and the upper part of the righting and extracting claw 5 can swing out of the claw accommodating groove 6 or swing back into the claw accommodating groove 6. The claw accommodating groove 6 is a rectangular groove, and the width of the righting and extracting claw 5 is slightly smaller than the width of the claw accommodating groove 6, and the length of the claw accommodating groove 6 can vertically accommodate the righting and extracting claw 5.

[0038] In this embodiment, the righting and extraction claw 5 is eccentrically installed on the rotating shaft 7. When the righting and extraction claw 5 is fully retracted into the claw accommodating groove 6, the righting and extraction claw 5 also presents an outward tilted state. Therefore, when the righting and extraction claw 5 is not constrained by external force, the righting and extraction claw 5 relies on its own weight to swing outward and extend against the bottom end surface of the claw accommodating groove 6. When the righting and extraction claw 5 is fully extended, it is close to a horizontal state, and it no longer continues to swing downward against the bottom end surface of the claw accommodating groove 6. When upward force is applied to the righting and extracting claw 5, the righting and extracting claw 5 swings upward and retracts. In order to prevent the righting and extracting claw 5 from being stuck in the claw accommodating groove 6 and unable to automatically extend after being fully retracted, a shoulder structure 8 is provided at the top of the claw accommodating groove 6 to prevent the righting and extracting claw 5 from excessively retracting. When the righting and extracting claw 5 is swung upward by an external force and contacts the shoulder structure 8, it stops. When no external force is applied, it automatically swings outward and extends.

[0039] This embodiment utilizes the eccentric installation method of the righting and extracting claw 5 to achieve the natural extension of the righting and extracting claw 5 by its own gravity, which does not require external power control and has the advantages of simple structure and easy use. Of course, the righting and extracting claw 5 can also be swung by telescopic power cylinder, but it requires a power supply or control system to assist in the righting. This method of telescopic power cylinder also falls within the scope of protection of this application, but due to its complex structure, it is prone to malfunction, especially when the use environment of this device is in the water under the well, which is not the optimal implementation method of this application. Therefore, the method of automatically extending by gravity in this embodiment is better.

[0040] The number of the righting and extracting claws 5 corresponds to the number of the claw accommodating grooves 6. The number of the righting and extracting claws 5 is at least two. When there are two, they are arranged symmetrically on the left and right. Of course, the number of the righting and extracting claws 5 can also be four or more. When there are three, the use effect is better.

[0041] Both ends of the rotating shaft 7 are respectively welded to the uprighting and extracting body 3 , and the uprighting and extracting claw 5 is rotatably mounted on the rotating shaft 7 .

[0042] The conical body 4 is formed by shrinking the bottom end of the uprighting and extracting body 3 downward. This structural form can reduce the resistance of the uprighting and extracting device when it moves downhole.

[0043] The outer peripheral surface of the upright extraction body 3 is also provided with a spiral structure, which is a spiral groove 9 provided on the outer surface of the upright extraction body 3. When the upright extraction device moves upward or downward, the water in the inner sleeve 10 contacts the spiral structure, which provides a rotational power for the upright extraction device, so that the upright extraction device rotates.

[0044] The straightening and extraction slot 11 is arranged near the bottom of the inner sleeve 10, and it can be provided with multiple layers, each layer is provided with the same number of straightening and extraction slots 11 as the number of the straightening and extraction claws 5, and there is an angle dislocation between the multiple layers, see Figure 4 When the righting and extracting device moves downward along the inner sleeve 10 to the bottom position of the inner sleeve 10, the righting and extracting device is dragged upward. When the righting and extracting device cannot be pulled upward, it means that the righting and extracting claw 5 is stuck in the corresponding righting and extracting slot 11, and when the righting and extracting device can be dragged upward, it means that the righting and extracting claw 5 is not stuck in the corresponding righting and extracting slot 11. During the righting and extracting device being dragged upward, it will rotate at an angle under the action of the spiral structure, and then continue to move the righting and extracting device downward. Repeatedly dragging upward and moving downward for many times will allow the righting and extracting device to automatically find the righting and extracting slot 11 of a certain layer. Multiple layers and angle misalignment are provided to quickly achieve snap-on connection.

[0045] The design of the spiral structure provides a rotational power for the righting and extracting device, which is used to realize the automatic snap-fitting cooperation between the righting and extracting device and the inner sleeve 10; when the spiral structure is not provided, the righting and extracting device can be repeatedly dragged upward and moved downward, and the righting and extracting device can also have a small angle position change under the action of water resistance, and can also realize automatic snap-fitting cooperation with the inner sleeve 10, but the righting and extracting device with the spiral structure has a more obvious angle change, which can realize quick cooperation with the inner sleeve 10.

[0046] The connector 2 can be fixed on the uprighting and extracting body 3 by welding, or can be integrally formed with the uprighting and extracting body 3 by mechanical processing.

[0047] The universal lifting ring 1 is a 360° universally rotatable lifting ring screw, which is threadedly mounted on the connector 2. The 360° universally rotatable lifting ring screw is a well-known product in the prior art, and its top ring structure is used to connect with the high-strength fiber rope, and its bottom end is used to be threadedly fixed with the connector 2. A universal structure that can rotate 360° freely is provided between the top and bottom ends, and the specific structure and working principle are not described here. This freely rotatable universal lifting ring 1 is used to adapt to the rotation of the righting extraction device in water.

[0048] The working principle of this embodiment is:

[0049] When the inner casing 10 is stuck when it is moving upward out of the well, the bottom end of the inner casing 10 is eccentrically close to or in contact with the geothermal well wall 12; the specific operation method of straightening is: fix the high-strength fiber rope on the universal lifting ring 1, and then extend the device from the top of the inner casing 10. At this time, the straightening and extraction claw 5 is constrained by the wall of the inner casing 10 and is in a retracted state. The straightening and extraction device moves downward along the wall of the inner casing 10. When it approaches the bottom position of the inner casing 10, the straightening and extraction device is repeatedly tentatively dragged upward and released. When it is unable to continue to be dragged upward, it means that the straightening and extraction claw 5 just corresponds to the position of the straightening and extraction slot 11. See the status for details. Figure 5 , Figure 6 and Figure 7 , the righting and extracting claw 5 is partially or fully extended, and the righting and extracting claw 5 is partially extended because the inner casing is eccentric, which causes the righting and extracting claw 5 to be restricted from extending by the outer geothermal well pipe wall 12; at this time, the device is dragged upward with force, and at least one of the righting and extracting grooves 11 will just press against the righting and extracting claw 5, and the inner casing 10 is dragged upward and becomes loose, and the righting and extracting claw 5 is pressed by the inner casing 10 and gradually swings outward, so that the inner casing 10 gradually moves away from the geothermal well pipe wall 12. The state after righting is shown in FIG. Figure 8 and Fig. 9 ;

[0050] After the inner casing 10 is straightened, the inner casing 10 and the straightening and extracting device are dragged upwards together. After the inner casing 10 is completely taken out from the well wall, the straightening and extracting device is removed.

[0051] The above shows and describes the basic principle, main features and advantages of the utility model. Those skilled in the art should understand that the utility model is not limited by the above embodiments. The above embodiments and descriptions are only for explaining the principle of the utility model. Without departing from the spirit and scope of the utility model, the utility model may have various changes and improvements, which fall within the scope of the utility model to be protected. The scope of protection claimed by the utility model is defined by the attached claims and their equivalents.

Claims

1. A casing straightening and extraction device for a deep geothermal well, characterized in that: include: The righting and extracting body is used to be placed in the inner casing for righting and auxiliary extraction. The surface of the righting and extracting body is provided with righting and extracting claws for clamping with the inner casing. At least two righting and extracting claws are arranged along the circumference of the righting and extracting body. The righting and extracting claws are swingably mounted on the righting and extracting body and can be retracted into the righting and extracting body or extended out of the righting and extracting body. A universal lifting ring is installed on the top of the uprighting and extracting body and is used for lifting the uprighting and extracting body.

2. The casing straightening and extraction device for a deep geothermal well according to claim 1, characterized in that: At least two claw accommodating grooves are arranged on the outer peripheral surface of the straightening and extraction body, and the number of the claw accommodating grooves corresponds one to one to the number of the straightening and extraction claws. The lower part of the straightening and extraction claw is connected to the lower part of the claw accommodating groove through a rotating shaft, and the upper part of the straightening and extraction claw can be swung out of the claw accommodating groove or swung back into the claw accommodating groove.

3. The casing straightening and extraction device for a deep geothermal well according to claim 2, characterized in that: The uprighting and extracting claw is eccentrically mounted on the rotating shaft, and the uprighting and extracting claw swings outwards by its own weight and extends out to abut against the bottom end surface of the claw accommodating groove.

4. The casing straightening and extraction device for a deep geothermal well according to claim 2, characterized in that: The two ends of the rotating shaft are respectively welded to the upright extraction body, and the upright extraction claw is rotatably mounted on the rotating shaft.

5. The casing straightening and extraction device for deep geothermal wells according to claim 1, characterized in that: A cone is provided at the lower part of the uprighting and extracting body, and the cone is formed by shrinking downward from the bottom end of the uprighting and extracting body.

6. The casing straightening and extraction device for deep geothermal wells according to claim 1, characterized in that: The outer peripheral surface of the uprighting and extracting body is also provided with a spiral structure.

7. The casing straightening and extraction device for a deep geothermal well according to claim 6, characterized in that: The spiral structure is a spiral groove arranged on the outer surface of the straightening and extraction body.

8. The casing straightening and extraction device for deep geothermal wells according to claim 1, characterized in that: A connecting head is fixed on the top of the uprighting and extracting body, and the universal lifting ring is installed on the connecting head.

9. The casing straightening and extraction device for a deep geothermal well according to claim 8, characterized in that: The universal lifting ring is a lifting ring screw capable of 360° universal rotation, and the lifting ring screw is threadedly mounted on the connecting head.

10. The casing straightening and extraction device for a deep geothermal well according to any one of claims 1 to 9, characterized in that: The inner sleeve has a wall surface provided with a righting and extracting groove corresponding to the righting and extracting claw. When the righting and extracting claw corresponds to the position of the righting and extracting groove, the righting and extracting claw swings outwards and extends into the righting and extracting groove.

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