Open type heat exchange inner pipe of geothermal well

Abstract

The open type heat exchange inner pipe of the geothermal well comprises a connecting pipe, the upper end and the lower end of the connecting pipe are connected with a second installation pipe and a first installation pipe respectively, a butt joint mechanism is installed between the connecting pipe and the second installation pipe, and the butt joint mechanism is used for connecting the second installation pipe with the first installation pipe on the adjacent heat exchange inner pipe. A limiting mechanism used for fixing and limiting the connecting pipe in the inner wall of the geothermal well is installed on the outer wall of the connecting pipe, the outer wall of the connecting pipe is further sleeved with a rubber inner sleeve, and the rubber inner sleeve is filled with diethyl ether. The geothermal well solves the problem that in the prior art, due to the fact that the inner wall of the geothermal well is smooth, an inner pipe is unstable in use.

Description

Technical Field

[0001] This utility model belongs to the field of geothermal well construction technology, specifically relating to the open heat exchange inner pipe of a geothermal well. Background Technology

[0002] Geothermal energy is a thermal energy resource derived from the Earth's interior. Due to its clean and environmentally friendly nature, good stability, and recyclability, it is a realistic and competitive renewable energy source.

[0003] During the construction of an open-source ground source heat pump system, a submersible pump needs to be lowered into the geothermal well and positioned below the dynamic water level. The submersible pump is installed inside an inner pipe, with the lower end of the inner pipe extending downwards into the geothermal well. Because the well wall of the geothermal well is relatively smooth, the inner pipe is prone to slippage and instability during installation, which can lead to safety hazards during use.

[0004] For example, the prior art disclosed in CN113446743B provides an open heat exchange inner pipe for a geothermal well, which is installed inside the geothermal well and includes a pump chamber section. An insulated steel pipe is connected to both the upper and lower ends of the pump chamber section. The insulated steel pipe located above the pump chamber section is the upper insulated steel pipe, and the insulated steel pipe located below the pump chamber section is the lower insulated steel pipe. A water intake pipe is also connected below the lower insulated steel pipe. A steel-plastic joint is also provided between the water intake pipe and the lower insulated steel pipe. The steel-plastic joint includes a connecting pipe fixed to the end of the insulated steel pipe, and a PE sleeve is sleeved on the outside of the connecting pipe. The PE sleeve and the connecting pipe are connected by a barbed snap ring. Although this solution improves the stability of the heat exchange system, during the installation and use of the inner pipe, due to the relatively smooth inner wall of the geothermal well, a stable fixation is not formed between the inner pipe and the inner wall of the geothermal well, resulting in instability and shaking of the inner pipe during operation, posing a safety hazard. Utility Model Content

[0005] The purpose of this invention is to provide an open heat exchange inner tube for geothermal wells, which solves the problem of instability in the use of the inner tube due to the smooth inner wall of the geothermal well in the prior art.

[0006] The technical solution adopted by this utility model is an open heat exchange inner pipe for a geothermal well, including a connecting pipe. The upper and lower ends of the connecting pipe are respectively connected to a second installation pipe and a first installation pipe. A docking mechanism is installed between the connecting pipe and the second installation pipe. The docking mechanism is used to connect the second installation pipe to the first installation pipe on the adjacent heat exchange inner pipe.

[0007] The outer wall of the connecting pipe is equipped with a limiting mechanism for fixing and limiting the connecting pipe within the inner wall of the geothermal well. The outer wall of the connecting pipe is also fitted with a rubber inner sleeve, which is filled with ether.

[0008] The present invention is further characterized in that,

[0009] The limiting mechanism includes two sets of first fixed discs, which are symmetrically distributed on the outer wall of the connecting pipe. Several rectangular sliding grooves are provided on the first fixed discs, which are distributed along the circumference of the first fixed discs.

[0010] A sliding strip is movably connected inside the rectangular sliding groove. A movable mating block is fixedly connected to the top of the sliding strip. A limit plug is fixedly connected to the side of the movable mating block opposite to the inner wall of the geothermal well. The limit plug is conical and its tip faces the inner wall of the geothermal well.

[0011] Each of the two sets of first fixed discs has a second fixed disc at one end opposite to the other. The two sets of second fixed discs are connected by a connecting fixed arm. The second fixed disc is movably connected to the outer wall of the connecting pipe.

[0012] The second fixed disc is provided with a number of curved sliding grooves, which are distributed along the circumference of the second fixed disc. The bottom of the sliding bar is movably connected to the inner wall of the corresponding curved sliding groove.

[0013] A drive motor is mounted on the upper end of the first set of fixed discs. A connecting gear is connected to the output end of the drive motor. A mating gear ring is fixedly connected to one end of the second fixed disc relative to the first fixed disc. The inner teeth of the mating gear ring mesh with the outer teeth of the connecting gear.

[0014] The inner wall of the rectangular sliding groove has a sliding opening along the direction of movement of the sliding bar. The sliding bar is slidably connected to the inner wall of the sliding opening on both sides of the sliding opening. Both the outer wall of the sliding bar and the inner wall of the sliding opening are coated with lubricating oil.

[0015] The docking mechanism includes a movable sleeve, which is movably connected to the outer wall of the second mounting tube and the connecting tube. An abutment ring is fixedly connected to the connecting tube, and a return spring is also sleeved on the outer wall of the connecting tube. One end of the return spring abuts against the abutment ring, and the other end abuts against the bottom of the movable sleeve.

[0016] The second installation tube has several tapered openings on its side wall. A contact ball is placed inside the tapered opening and is fixed inside the tapered opening by the pressure of the inner wall of the movable sleeve.

[0017] Several conical openings are distributed along the circumference of the second mounting tube. The diameter of the conical openings gradually decreases from the outside of the second mounting tube to the inside of the tube, and the diameter of the opening inside the tube is smaller than the diameter of the contact ball.

[0018] The movable sleeve has an annular groove inside, and the diameter of the contact ball is smaller than the width of the groove.

[0019] The first mounting tube has a mating opening that is adapted to engage with the abutting ball.

[0020] The beneficial effects of this utility model are:

[0021] (1) The open heat exchange inner pipe of the geothermal well of this utility model has a limiting mechanism set on the outer wall of the connecting pipe. When the drive motor drives the second fixed disc to rotate, the curved sliding groove on the second fixed disc causes the sliding strip to push the limiting block into the inner wall of the geothermal well, which effectively improves the stability of the inner pipe during operation. At the same time, a rubber inner sleeve is sleeved on the outside of the connecting pipe. The inside of the rubber inner sleeve is filled with some ether. When the inside of the connecting pipe is heated, the connecting pipe will transfer the heat to the rubber inner sleeve. At this time, the ether inside the rubber inner sleeve expands, and the outer wall of the rubber inner sleeve will abut against the inner wall of the geothermal well, so that the connecting pipe can be better fixed in the inner wall of the geothermal well.

[0022] (2) The open heat exchange inner pipe of the geothermal well of this utility model greatly improves the efficiency of direct installation and disassembly of adjacent inner pipes by setting a docking mechanism between the connecting pipe and the second installation pipe. Only by pulling the movable sleeve, the first installation pipe can be clamped to the inside of the second installation pipe under the action of the abutting ball. Disassembly can also be done by simply pulling the movable sleeve, which greatly reduces the workload of workers and improves work efficiency. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the structure of the open heat exchange inner tube of the geothermal well of this utility model;

[0024] Figure 2 This is a schematic diagram of the structure of the open heat exchange inner tube limiting mechanism for geothermal wells according to this utility model;

[0025] Figure 3 This is an enlarged structural schematic diagram of the rectangular sliding groove position in the open heat exchange inner tube of the geothermal well of this utility model;

[0026] Figure 4 This is a cross-sectional view of the docking mechanism in the open heat exchange inner tube of the geothermal well of this utility model.

[0027] In the diagram, 1. Connecting pipe, 2. Second mounting pipe, 3. First mounting pipe, 4. Mating opening, 5. Rubber inner sleeve, 6. Connecting fixed arm, 7. Moving mating block, 8. Rectangular sliding groove, 9. First fixed disc, 10. Limiting insert, 12. Drive motor, 13. Connecting gear, 14. Mating gear ring, 15. Second fixed disc, 16. Sliding port, 17. Sliding strip, 18. Conical opening, 19. Movable groove, 20. Abutting ball, 21. Movable sleeve, 22. Return spring, 23. Curved sliding groove, 101. Docking mechanism, 201. Limiting mechanism. Detailed Implementation

[0028] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0029] Example 1

[0030] This utility model relates to an open heat exchange inner pipe for geothermal wells, such as... Figure 1 As shown, it includes a connecting pipe 1, with a second mounting pipe 2 and a first mounting pipe 3 connected to its upper and lower ends respectively. A docking mechanism 101 is installed between the connecting pipe 1 and the second mounting pipe 2. The docking mechanism 101 is used to connect the second mounting pipe 2 to the first mounting pipe 3 on the adjacent heat exchange inner pipe.

[0031] A limiting mechanism 201 for fixing and limiting the connecting pipe 1 in the inner wall of the geothermal well is installed on the outer wall of the connecting pipe 1. A rubber inner sleeve 5 is also sleeved on the outer wall of the connecting pipe 1, and a small amount of ether is filled in the rubber inner sleeve 5.

[0032] When the inside of the connecting pipe 1 is heated, the connecting pipe 1 will transfer the heat to the rubber inner sleeve 5. At this time, the ether inside the rubber inner sleeve 5 expands, and the outer wall of the rubber inner sleeve 5 will abut against the inner wall of the geothermal well, so that the connecting pipe 1 can be better fixed in the inner wall of the geothermal well.

[0033] Example 2

[0034] This utility model relates to an open heat exchange inner pipe for geothermal wells, such as... Figure 1 As shown, it includes a connecting pipe 1, with a second mounting pipe 2 and a first mounting pipe 3 connected to its upper and lower ends respectively. A docking mechanism 101 is installed between the connecting pipe 1 and the second mounting pipe 2. The docking mechanism 101 is used to connect the second mounting pipe 2 to the first mounting pipe 3 on the adjacent heat exchange inner pipe.

[0035] A limiting mechanism 201 for fixing and limiting the connecting pipe 1 in the inner wall of the geothermal well is installed on the outer wall of the connecting pipe 1. A rubber inner sleeve 5 is also sleeved on the outer wall of the connecting pipe 1, and a small amount of ether is filled in the rubber inner sleeve 5.

[0036] like Figure 2 As shown, the limiting mechanism 201 includes two sets of first fixed discs 9. The two sets of first fixed discs 9 are symmetrically distributed on the outer wall of the connecting pipe 1. Several rectangular sliding grooves 8 are provided on the first fixed discs 9. The several rectangular sliding grooves 8 are distributed along the circumference of the first fixed discs 9.

[0037] A sliding strip 17 is movably connected within a rectangular sliding groove 8. A movable mating block 7 is fixedly connected to the top of the sliding strip 17. A limiting insert 10 is fixedly connected to the side of the movable mating block 7 opposite to the inner wall of the geothermal well. The limiting insert 10 is conical in shape, with its tip facing the inner wall of the geothermal well. The conical shape allows the limiting insert 10 to be better inserted into the inner wall of the well.

[0038] In this embodiment, when the connecting pipe 1 needs to be fixed, the sliding strip 17 can drive the limiting plug 10 to be inserted into the inner wall of the geothermal well.

[0039] Example 3

[0040] Although the sliding bar 17 can drive the limiting plug 10 to be inserted into the inner wall of the geothermal well in the above embodiment 2, when the connecting pipe 1 is located in the geothermal well, the ground operator cannot complete the oscillation of the sliding bar 17. This embodiment improves the solution of embodiment 2 based on embodiment 2.

[0041] Furthermore, each of the two sets of first fixed discs 9 is provided with a second fixed disc 15 at one end opposite to the other. The two sets of second fixed discs 15 are connected by a connecting fixed arm 6, and the second fixed disc 15 is movably connected to the outer wall of the connecting pipe 1.

[0042] The second fixed disc 15 is provided with a plurality of curved sliding grooves 23, which are distributed along the circumference of the second fixed disc 15. The bottom of the sliding bar 17 is movably connected to the inner wall of the corresponding curved sliding groove 23.

[0043] A drive motor 12 is mounted on the upper end of the first fixed disk 9. The output end of the drive motor 12 is connected to a connecting gear 13. A mating gear ring 14 is fixedly connected to one end of the second fixed disk 15 relative to the first fixed disk 9. The inner teeth of the mating gear ring 14 mesh with the outer teeth of the connecting gear 13.

[0044] In this embodiment, after the connecting pipe 1 is lowered into the geothermal well, when it is necessary to limit the connection pipe 1, it is only necessary to start the drive motor 12. The drive motor 12 will drive the mating gear ring 14 to rotate, and the mating gear ring 14 will drive the corresponding second fixed disc 15 to rotate. Since the two sets of second fixed discs 15 are connected to each other, all the second fixed discs 15 will rotate at the same time. When the second fixed disc 15 rotates, it will drive the corresponding curved sliding groove 23 to move. When the curved sliding groove 23 moves, it will drive the sliding strip 17 to move. The sliding strip 17 will drive the moving mating block 7 and the limiting plug 10 to move. When the moving mating block 7 moves, it will drive the limiting plug 10 to abut against the inner wall of the well, thereby fixing the connecting pipe 1.

[0045] After the work is completed, start the drive motor 12. The drive motor 12 drives the connecting gear 13 to rotate in the opposite direction. The connecting gear 13 drives all the second fixed discs 15 to rotate. The second fixed discs 15 drive the sliding strip 17 to move in the opposite direction through the curved sliding groove 23, so that the limit plug 10 disengages from the well wall, and the connecting pipe 1 can be taken out and disassembled.

[0046] Example 4

[0047] This embodiment is based on the above embodiment 3, such as Figure 3 As shown, the inner wall of the rectangular sliding groove 8 has a sliding opening 16 along the movement direction of the sliding bar 17. The sliding bar 17 is slidably connected to the inner wall of the sliding opening 16 on both sides relative to the sliding opening 16. Both the outer wall of the sliding bar 17 and the inner wall of the sliding opening 16 are coated with lubricating oil.

[0048] When the slider 17 moves, the sliding port 16 can guide the slider 17 and limit its movement, thus improving the stability of the slider 17 during movement. The lubricating oil can also reduce the friction between the sliding port 16 and the slider 17, extending the service life of both the slider 17 and the sliding port 16.

[0049] Example 5

[0050] In this embodiment, the geothermal well has an open heat exchange inner pipe, such as... Figure 1 As shown, it includes a connecting pipe 1, with a second mounting pipe 2 and a first mounting pipe 3 connected to its upper and lower ends respectively. The second mounting pipe 2, the first mounting pipe 3 and the connecting pipe 1 are all made of stainless steel. Stainless steel has high strength and good corrosion resistance, and can withstand the complex geological environment and the corrosive effect of geothermal water in the geothermal well. Under high temperature environment, the performance of stainless steel remains stable and it is not easy to deform or crack, which can ensure the long-term stable operation of the heat exchange inner tube.

[0051] A docking mechanism 101 is installed between the connecting pipe 1 and the second mounting pipe 2. The docking mechanism 101 is used to connect the second mounting pipe 2 to the first mounting pipe 3 on the adjacent heat exchange inner pipe.

[0052] A limiting mechanism 201 for fixing and limiting the connecting pipe 1 in the inner wall of the geothermal well is installed on the outer wall of the connecting pipe 1. A rubber inner sleeve 5 is also sleeved on the outer wall of the connecting pipe 1, and a small amount of ether is filled in the rubber inner sleeve 5.

[0053] like Figure 2 As shown, the limiting mechanism 201 includes two sets of first fixed discs 9. The two sets of first fixed discs 9 are symmetrically distributed on the outer wall of the connecting pipe 1. Several rectangular sliding grooves 8 are provided on the first fixed discs 9. The several rectangular sliding grooves 8 are distributed along the circumference of the first fixed discs 9.

[0054] A sliding strip 17 is movably connected within a rectangular sliding groove 8. A movable mating block 7 is fixedly connected to the top of the sliding strip 17. A limiting insert 10 is fixedly connected to the side of the movable mating block 7 opposite to the inner wall of the geothermal well. The limiting insert 10 is conical in shape, with its tip facing the inner wall of the geothermal well. The conical shape allows the limiting insert 10 to be better inserted into the inner wall of the well.

[0055] Furthermore, each of the two sets of first fixed discs 9 is provided with a second fixed disc 15 at one end opposite to the other. The two sets of second fixed discs 15 are connected by a connecting fixed arm 6, and the second fixed disc 15 is movably connected to the outer wall of the connecting pipe 1.

[0056] The second fixed disc 15 is provided with a plurality of curved sliding grooves 23, which are distributed along the circumference of the second fixed disc 15. The bottom of the sliding bar 17 is movably connected to the inner wall of the corresponding curved sliding groove 23.

[0057] A drive motor 12 is mounted on the upper end of the first fixed disk 9. The output end of the drive motor 12 is connected to a connecting gear 13. A mating gear ring 14 is fixedly connected to one end of the second fixed disk 15 relative to the first fixed disk 9. The inner teeth of the mating gear ring 14 mesh with the outer teeth of the connecting gear 13.

[0058] like Figure 4 As shown, the docking mechanism 101 includes a movable sleeve 21, which is movably connected to the outer wall of the second mounting tube 2 and the connecting tube 1. An abutment ring is fixedly connected to the connecting tube 1, and a return spring 22 is also sleeved on the outer wall of the connecting tube 1. One end of the return spring 22 abuts against the abutment ring, and the other end abuts against the bottom of the movable sleeve 21.

[0059] The second mounting tube 2 has several tapered openings 18 on its side wall. An abutment ball 20 is placed inside the tapered opening 18. The abutment ball 20 is fixed inside the tapered opening 18 by the compression of the inner wall of the movable sleeve 21.

[0060] The first mounting tube 3 has a mating opening 4 that is compatible with and snaps into the abutting ball 20.

[0061] Furthermore, the movable sleeve 21 has an annular movable groove 19 inside, and the diameter of the abutting ball 20 is smaller than the width of the movable groove 19.

[0062] When it is necessary to connect the two sets of connecting pipes 1, simply pull the movable sleeve 21. When the movable groove 19 inside the movable sleeve 21 moves to be parallel to each set of abutment balls 20, the space between the movable groove 19 and the conical opening 18 increases, allowing the abutment balls 20 enough time to move and align with the mating opening 4 on the first mounting tube 3 on the outer wall of the two sets of connecting pipes 1 and the abutment balls 20. Then, release the control of the movable sleeve 21, and the return spring 22 will drive the movable sleeve 21 to return to its original position. The inner wall of the movable sleeve 21 will abut with the abutment balls 20, and the abutment balls 20 will engage with the inner wall of the curved sliding groove 23 on the outer wall of the first mounting tube 3. At this point, the two sets of connecting pipes 1 can be connected.

[0063] After use, simply pull the movable sleeve 21 again to position the movable groove 19 at the abutting ball 20. Since the abutting ball 20 is located inside the movable groove 19, the two sets of connecting pipes 1 can be disassembled more easily.

[0064] Example 6

[0065] Based on Embodiment 5 above, in this embodiment, several conical openings 18 are distributed along the circumference of the second mounting tube 2. The diameter of the conical openings 18 gradually decreases from the outside of the second mounting tube 2 to the inside of the tube, and the diameter of the opening inside the tube is smaller than the diameter of the contact ball 20.

[0066] Finally, it should be noted that in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0067] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0068] The above description of the disclosed embodiments enables those skilled in the art to make or use this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An open heat exchange inner pipe for a geothermal well, characterized in that, Includes a connecting pipe (1), with a second mounting pipe (2) and a first mounting pipe (3) connected to the upper and lower ends of the connecting pipe (1) respectively. A docking mechanism (101) is installed between the connecting pipe (1) and the second mounting pipe (2). The docking mechanism (101) is used to connect the second mounting pipe (2) to the first mounting pipe (3) on the adjacent heat exchange inner pipe. The outer wall of the connecting pipe (1) is equipped with a limiting mechanism (201) for fixing and limiting the connecting pipe (1) in the inner wall of the geothermal well. The outer wall of the connecting pipe (1) is also fitted with a rubber inner sleeve (5), which is filled with ether.

2. The open-heat-exchange inner tube of a geothermal well according to claim 1, characterized by, The limiting mechanism (201) includes two sets of first fixed discs (9), which are symmetrically distributed on the outer wall of the connecting pipe (1). Several rectangular sliding grooves (8) are provided on the first fixed discs (9), which are distributed along the circumference of the first fixed discs (9). A sliding bar (17) is movably connected inside the rectangular sliding groove (8). A movable mating block (7) is fixedly connected to the top of the sliding bar (17). A limiting plug (10) is fixedly connected to the side of the movable mating block (7) opposite to the inner wall of the geothermal well. The limiting plug (10) is conical and its tip faces the inner wall of the geothermal well.

3. The open-heat-exchange inner tube of a geothermal well according to claim 2, wherein Each of the two sets of first fixed discs (9) is provided with a second fixed disc (15) at one end opposite to each other. The two sets of second fixed discs (15) are connected by a connecting fixed arm (6). The second fixed disc (15) is movably connected to the outer wall of the connecting pipe (1). The second fixed disk (15) is provided with a plurality of curved sliding grooves (23), and the plurality of curved sliding grooves (23) are distributed along the circumferential direction of the second fixed disk (15). The bottom of the sliding bar (17) is movably connected to the inner wall of the corresponding curved sliding groove (23).

4. The open-heat-exchange inner tube of a geothermal well according to claim 3, characterized by, One of the first fixed disks (9) has a drive motor (12) installed on its upper end. The output end of the drive motor (12) is connected to a connecting gear (13). The second fixed disk (15) is fixedly connected to a mating gear ring (14) at one end relative to the first fixed disk (9). The inner teeth of the mating gear ring (14) mesh with the outer teeth of the connecting gear (13).

5. The open heat exchange inner pipe of a geothermal well according to claim 2, characterized in that, The inner wall of the rectangular sliding groove (8) has a sliding opening (16) along the movement direction of the sliding bar (17). The sliding bar (17) is slidably connected to the inner wall of the sliding opening (16) on both sides relative to the sliding opening (16). The outer wall of the sliding bar (17) and the inner wall of the sliding opening (16) are both coated with lubricating oil.

6. The open-heat-exchange inner tube of a geothermal well according to claim 1, wherein The docking mechanism (101) includes a movable sleeve (21), which is movably connected to the outer wall of the second mounting tube (2) and the connecting tube (1). An abutment ring is fixedly connected to the connecting tube (1), and a return spring (22) is also sleeved on the outer wall of the connecting tube (1). One end of the return spring (22) abuts against the abutment ring, and the other end abuts against the bottom of the movable sleeve (21). The second mounting tube (2) has several conical openings (18) on its side wall. An abutment ball (20) is placed inside the conical opening (18). The abutment ball (20) is fixed inside the conical opening (18) under the pressure of the inner wall of the movable sleeve (21).

7. The open-heat-exchange inner tube of a geothermal well according to claim 6, characterized by, Several conical openings (18) are distributed along the circumference of the second mounting tube (2). The diameter of the conical openings (18) gradually decreases from the outside of the second mounting tube (2) to the inside, and the diameter of the opening inside the tube is smaller than the diameter of the contact ball (20).

8. The open heat exchange inner pipe of a geothermal well according to claim 7, characterized in that, The movable sleeve (21) has an annular movable groove (19) inside, and the diameter of the abutting ball (20) is smaller than the width of the movable groove (19).

9. The open-heat-exchange inner tube of a geothermal well according to claim 7, wherein The first mounting tube (3) has a mating opening (4) that is compatible with and snaps into the abutting ball (20).

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