A packer for water injection test

Abstract

The application discloses a drilling water injection test packer, and belongs to the technical field of drilling water injection test packer equipment. The drilling water injection test packer comprises a drill bit which is fixedly connected with a support at the top; a water injection pipe and an oil pipe are axially and penetratingly arranged on the support; an axial water injection cavity which is communicated with the water injection pipe is penetratingly arranged on the drill bit; a spiral plate is fixedly connected to the outer wall surface of the drill bit; an annular cavity is arranged around the water injection cavity in the drill bit, and the annular cavity is communicated with the oil pipe; a plurality of insertion slots are radially and symmetrically arranged around the water injection cavity at the lower part of the annular cavity on the drill bit, the annular cavity is communicated with the insertion slots through a connecting opening, and the insertion slots are communicated with each other; and an insertion plate is movably connected in the insertion slot. The drilling water injection test packer solves the problems that the existing drilling packer device is prone to sliding in the drilling, the uneven inner wall of the drilling causes the sealing equipment to be unable to completely seal the drilling, and the insertion plate is unable to be retracted into the sealing equipment due to the attachment of foreign matters such as silt on the insertion plate when the insertion plate is retracted.

Description

Technical Field

[0001] This invention belongs to the technical field of borehole water injection test sealing equipment, and relates to a borehole water injection test sealing device. Background Technology

[0002] When conducting water injection tests on boreholes, it is often necessary to seal the borehole, which requires the use of borehole water injection test sealing equipment. Chinese utility model patent application number 200920113223.3 discloses a sealing device for water injection tests on large-diameter boreholes. It uses the original drilling rod and connects a set of rubber plugs in series at the upper part of the test section to seal the water. The expansion of the rubber plugs depends on the sum of the weight of the drilling rod and the pressure P applied by the drilling machine, so that the set of rubber plugs are simultaneously compressed and expanded. After the test, the pressure on the rubber plugs is released, and the loosened rubber plugs are lifted to restore the rubber plugs to their original shape. According to its publicly available technical solutions, existing borehole water injection test packing equipment has several drawbacks during use. First, when injecting water into the borehole, the inner wall of the borehole is slippery, causing the packing equipment to be squeezed and pushed, which is detrimental to ensuring the packing equipment's stability. Second, when sealing the borehole, unevenness of the inner wall of the borehole can prevent the packing equipment from completely sealing the borehole, allowing water to easily seep through cracks and capillaries on the inner wall of the borehole, which is also detrimental to ensuring the sealing effect. Third, when using mechanisms such as insert plates to insert into the inner wall of the borehole to ensure fixation and sealing, the insert plates are prone to being unable to be retracted into the packing equipment due to foreign matter such as mud and sand adhering to them, which is detrimental to the quick removal of the packing equipment. Summary of the Invention

[0003] The purpose of this invention is to solve the technical problems in the prior art where the borehole sealing device slips during drilling, the unevenness of the borehole inner wall causes the sealing device to fail to completely seal the borehole, and the insertion plate is easily unable to be retracted into the sealing device due to foreign objects such as mud and sand adhering to the insertion plate. The invention provides a borehole water injection test sealing device.

[0004] To achieve the above objectives, the present invention employs the following technical solution:

[0005] In a first aspect, the present invention provides a sealing device for a borehole water injection test, comprising a drill bit with a support fixedly connected to its top; a water injection pipe and an oil pipe axially penetrating the support; a water injection cavity communicating with the water injection pipe axially penetrating the drill bit; a spiral plate fixedly connected to the outer wall of the drill bit, the diameter of the spiral plate being larger than the inner diameter of the borehole; an annular cavity arranged around the water injection cavity in the drill bit, the annular cavity communicating with the oil pipe; a plurality of slots radially symmetrically arranged around the water injection cavity at the lower part of the annular cavity on the drill bit, the annular cavity communicating with the slots through connecting ports, the slots communicating with each other; an insert plate movably connected to the slot, a chuck fixedly connected to one end of the insert plate facing the outside of the slot, the chuck having a groove, the groove having a rubber sleeve; a through hole on the insert plate for communicating the groove with the slot; when hydraulic oil is injected into the annular cavity through the oil pipe, the hydraulic oil enters each slot, and the hydraulic pressure pushes the insert plate out of the slot, the diameter of the insert plate when fully pushed out of the slot being larger than the inner diameter of the borehole;

[0006] The drill bit has a groove inside, and a spring is installed in the groove. One end of the spring is fixed to the wall of the groove, and the other end is fixedly connected to a scraper. When the spring is in a free state, the scraper contacts the wall of the insert plate at the non-clamping part.

[0007] A further improvement of the present invention is as follows:

[0008] The slots are evenly arranged radially around the water injection cavity; each layer of the spiral plate has a slot in each spiral spacing.

[0009] The rubber sleeve has an inner cavity containing a water-absorbing and expanding material, and the clip head has a filter hole, through which the inner cavity communicates with the outside.

[0010] The water-absorbing and swelling material is a water-absorbing bead.

[0011] The card head has two symmetrical sliding grooves on both sides.

[0012] The support is fixed to the top of the drill bit by welding, the cone is fixed to the bottom of the drill bit by welding, and a spiral plate is fixedly connected to the outer wall of the drill bit by welding.

[0013] Both the water injection pipe and the oil pipe are fixed to the support by welding.

[0014] The outer diameter of the card head is larger than the outer diameter of the insert plate, and the card head and the insert plate are integrally formed.

[0015] A pointed cone is fixedly connected to the top of the drill bit, and a water injection channel communicating with the water injection chamber is provided on the pointed cone. A one-way valve is provided at the outlet of the water injection channel.

[0016] The water injection channel is V-shaped, which divides the fluid flowing out of the water injection chamber into two streams and discharges them from the pointed cone.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] This invention discloses a borehole water injection test sealing device. In use, the drill bit is screwed into the borehole through a spiral plate. The diameter of the spiral plate is larger than the inner diameter of the borehole, allowing it to pass through the inner wall of the borehole and extend to the inner side of the soil layer outside the borehole until the drill bit is fully rotated and pushed into the borehole. Hydraulic oil is injected into the annular cavity through an oil pipe, and the hydraulic oil enters the slot through a connector. Hydraulic pressure is used to push the insert plate out from the inside of the slot and clamp the chuck onto the inner wall of the borehole, or the chuck passes through the inner wall of the borehole and extends to the inner side of the soil layer outside the borehole. By having both the spiral plate and the chuck inserted into the outer side of the inner wall of the borehole, the upward or rotational movement of the drill bit is effectively prevented, ensuring the drill bit's secure fixation and preventing loosening due to water pressure at the bottom of the borehole, thus ensuring the sealing device's secure fixation.

[0019] Furthermore, in use, the borehole water injection test sealing device allows hydraulic oil to enter the inner side of the groove through the through hole, squeezing and expanding the rubber sleeve inside the groove. The rubber sleeve seals the top and bottom of the insert plate on the surfaces of the upper and lower spiral plates it contacts, respectively. Simultaneously, the rubber sleeve seals the chuck against the inner wall of the borehole. During the borehole water injection test, high-pressure water is injected downwards into the bottom of the borehole through the injection pipe and injection chamber, pushing open the one-way valve. The water pressure flows upwards to the bottom of the drill bit, then moves in the opposite direction along the spiral plates to the insert rod that has moved to the outside of the drill bit. The clamping head squeezes the water, which enters the inner cavity through the filter holes. The water-absorbing beads inside the cavity absorb water and expand, further increasing the sealing pressure of the rubber sleeve on the borehole wall and the spiral plate. Even if the water passes through the bottom insert plate and clamping head under pressure, multiple sealing units will then perform sealing work, thereby effectively ensuring the sealing effect of the borehole water injection test. This avoids the sealing device being unable to completely seal the borehole due to unevenness of the borehole inner wall, and prevents water from penetrating through cracks and capillaries on the borehole inner wall, ensuring the sealing effect of the borehole.

[0020] Furthermore, after the borehole water injection test packer completes the test, hydraulic oil is extracted through the oil pipe, and the insert plate is sucked into the inside of the slot. The scraper is clamped on both sides of the insert plate or chuck under the elastic force of the spring, and can slide inside the groove according to the width change of the insert plate and chuck. The scraper effectively scrapes off the impurities attached to the insert plate and chuck, avoiding the insert plate and chuck from being unable to retract smoothly into the slot due to impurities getting stuck inside the slot. It also ensures that the drill bit can be quickly moved upward from the inside of the borehole by the reverse rotation of the spiral plate, ensuring the rapid removal of the packer. Attached Figure Description

[0021] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the structure of a borehole water injection test sealing device according to the present invention;

[0023] Figure 2 This is a cross-sectional view of a borehole water injection test sealing device according to the present invention;

[0024] Figure 3 This is a top sectional view of a borehole water injection test sealing device according to the present invention;

[0025] Figure 4 This is a cross-sectional view of the top of a borehole water injection test sealing device according to the present invention;

[0026] Figure 5 This is a top sectional view of the groove of a borehole water injection test sealing device according to the present invention.

[0027] The components are: 1. Drill bit; 2. Support; 3. Cone; 4. Check valve; 5. Water injection pipe; 6. Water injection chamber; 7. Spiral plate; 8. Slot; 9. Insert plate; 10. Annular cavity; 11. Oil pipe; 12. Connecting port; 13. Groove; 14. Through hole; 15. Rubber sleeve; 16. Inner cavity; 17. Water-absorbing beads; 18. Filter hole; 19. Scraper; 20. Spring; 21. Chuck; 22. Slide groove. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0029] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0030] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0031] In the description of the embodiments of the present invention, it should be noted that if terms such as "upper," "lower," "horizontal," or "inner" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of the invention is in use, they are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention. Furthermore, terms such as "first" and "second" are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0032] Furthermore, the use of the term "horizontal" does not imply that the component must be absolutely horizontal, but rather that it can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0033] In the description of the embodiments of the present invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in the present invention according to the specific circumstances.

[0034] The present invention will now be described in further detail with reference to the accompanying drawings:

[0035] See Figure 1 and Figure 2 This invention discloses a borehole water injection test sealing device, comprising a drill bit 1 with a support 2 welded to its top; a water injection pipe 5 and an oil pipe 11 axially penetrating the support 2; a water injection chamber 6 axially penetrating the drill bit 1 and communicating with the water injection pipe 5; a spiral plate 7 welded to the outer wall of the drill bit 1, the diameter of the spiral plate 7 being larger than the inner diameter of the borehole; a pointed cone 3 fixedly connected to the top of the drill bit 1, the pointed cone 3 having a water injection channel communicating with the water injection chamber 10, and a one-way valve 4 provided at the outlet of the water injection channel. The water injection channel is V-shaped, dividing the fluid flowing out of the water injection chamber into two paths that are discharged from the pointed cone 3.

[0036] This invention discloses a borehole water injection test sealing device. In use, the drill bit is screwed into the borehole through a spiral plate. The diameter of the spiral plate is larger than the inner diameter of the borehole, allowing it to pass through the inner wall of the borehole and extend to the inner side of the soil layer outside the borehole until the drill bit is fully rotated and pushed into the borehole. Hydraulic oil is injected into the annular cavity through an oil pipe, and the hydraulic oil enters the slot through a connector. Hydraulic pressure is used to push the insert plate out from the inside of the slot and clamp the chuck onto the inner wall of the borehole, or the chuck passes through the inner wall of the borehole and extends to the inner side of the soil layer outside the borehole. By having both the spiral plate and the chuck inserted into the outer side of the inner wall of the borehole, the upward or rotational movement of the drill bit is effectively prevented, ensuring the drill bit's secure fixation and preventing loosening due to water pressure at the bottom of the borehole, thus ensuring the sealing device's secure fixation.

[0037] See Figure 3 and Figure 4 The drill bit 1 has an annular cavity 10 surrounding the water injection cavity 6, which is connected to the oil pipe 11. Four slots 8 are radially symmetrically arranged on the drill bit 1 at the lower part of the annular cavity 10 around the water injection cavity 6. Each layer of the spiral plate 7 has one layer of slots 8. The annular cavity 10 is connected to the slots 8 through a connecting port 12, and the slots 8 are interconnected. An insert plate 9 is movably connected to each slot 8. A chuck 21 is fixedly connected to one end of the insert plate 9 facing outwards from the slot 8. The outer diameter of the chuck 21 is larger than the outer diameter of the insert plate 9, and the chuck 21 and the insert plate 9 are integrally formed. A groove 13 is provided in the chuck 21, and a rubber sleeve 15 is provided in the groove 13. An inner cavity 16 is provided in the rubber sleeve 15, and water-absorbing beads 17 are provided in the inner cavity 16. A filter hole 18 is provided on the chuck 21, and the inner cavity 16 is connected to the outside through the filter hole 18. The insert plate 9 is provided with a through hole 14 for communicating the groove 13 with the slot 8; when hydraulic oil is injected into the annular cavity 10 through the oil pipe 11, the hydraulic oil enters each slot 8, and the insert plate 9 is pushed out of the slot 8 by hydraulic pressure. The diameter of the insert plate 9 when it is fully pushed out of the slot 8 is greater than the inner diameter of the drilled hole.

[0038] In use, the borehole water injection test sealing device allows hydraulic oil to enter the inner side of the groove through the through hole, compressing and expanding the rubber sleeve inside the groove. The rubber sleeve seals the top and bottom of the insert plate against the surfaces of the upper and lower spiral plates it contacts, respectively. Simultaneously, the rubber sleeve seals the chuck against the inner wall of the borehole. During the borehole water injection test, high-pressure water is injected downwards into the bottom of the borehole through the injection pipe and injection chamber, pushing open the one-way valve. The water pressure flows upwards to the bottom of the drill bit, then moves in the opposite direction along the spiral plates, impacting the insert rod and chuck that have moved to the outside of the drill bit. During the compression process, water enters the inner cavity through the filter holes. The water-absorbing beads inside the inner cavity absorb water and expand, further increasing the sealing pressure of the rubber sleeve on the inner wall of the borehole and the spiral plate. Even if water passes through the bottom insert plate and clamp under pressure, multiple sealing units will then perform sealing work, thereby effectively ensuring the sealing effect of the borehole water injection test. This avoids the sealing device being unable to completely seal the borehole due to unevenness of the inner wall of the borehole, and prevents water from penetrating through cracks and capillaries on the inner wall of the borehole, ensuring the sealing effect of the borehole.

[0039] See Figure 5 The drill bit 1 has a groove 22 inside, and two grooves 22 are symmetrically arranged on both sides of the chuck 21. A spring 20 is installed in the groove 22. One end of the spring 20 is fixed to the wall of the groove 22, and the other end is fixedly connected to a scraper 19. When the spring 20 is in a free state, the scraper 19 contacts the wall of the insert plate 9 at the non-chuck 21 position.

[0040] After the test is completed, the hydraulic oil in this borehole water injection test packing device is extracted through the oil pipe, and the insert plate is sucked into the inside of the slot. The scraper is clamped on both sides of the insert plate or chuck under the elastic force of the spring, and can slide inside the groove according to the width change of the insert plate and chuck. The scraper effectively scrapes off the impurities attached to the insert plate and chuck, and avoids the insert plate and chuck from being unable to retract smoothly into the slot due to impurities getting stuck inside the slot. It also ensures that the drill bit can be quickly moved upward from the inside of the borehole by the reverse rotation of the spiral plate, ensuring the rapid removal of the packing device.

[0041] The working process of this invention is as follows:

[0042] A borehole water injection test sealing device of the present invention includes a drill bit 1 and a support 2. A water injection assembly is installed on the support 2, the water injection assembly including a water injection pipe 5 and a water injection cavity 6. A one-way assembly is installed at the bottom of the drill bit 1, the one-way assembly including a cone 3 and a one-way valve 4. A fixing assembly is installed on the drill bit 1, the fixing assembly including a spiral plate 7 and a insert plate 9. A clamping assembly is installed on the insert plate 9, the clamping assembly including a chuck 21 and a groove 13. A sealing assembly is installed inside the groove 13, the sealing assembly including a rubber sleeve 15 and water-absorbing beads 17. A cleaning assembly is installed on the drill bit 1, the cleaning assembly including a scraper 19 and a spring 20. An annular cavity 10 is opened at the top of the drill bit 1. An oil pipe 11 is welded to the top of the support 2. The bottom end of the oil pipe 11 is connected to the annular cavity 10. The bottom of the annular cavity 10 is connected to a slot 8 through a connecting port 12. The slot 8 is connected to a connecting port 12 through a connecting port 12 through a connecting port 13. The openings 12 are interconnected. A groove 22 is provided on the inner side of the drill bit 1. One end of the scraper 19 is connected to the inner wall of the groove 22 via a spring 20. The other end of the scraper 19 passes through the groove 22 and is secured to the outer side of the chuck 21 or the insert plate 9. The scrapers 19 are symmetrically distributed on both sides of the chuck 21. After the experiment is completed, hydraulic oil is extracted through the oil pipe 11, and the insert plate 9 is sucked into the inner side of the slot 8. The scraper 19 is secured to the insert plate 9 under the elastic force of the spring 20. The slide plate 9 and the chuck 21 can slide on the inside of the groove 22 according to the width of the insert plate 9 and the chuck 21. The scraper 19 can effectively scrape off the impurities attached to the insert plate 9 and the chuck 21, and prevent the insert plate 9 and the chuck 21 from being unable to retract smoothly into the inside of the slot 8 due to impurities getting stuck in the inside of the slot 8. It also ensures that the drill bit 1 can be quickly moved upward from the inside of the drill hole by the reverse rotation of the spiral plate 7, and ensures the rapid removal of the sealing device.

[0043] The spiral plate 7 is welded to the outer side of the drill bit 1. A slot 8 is formed on the inner side of the drill bit 1. The insert plate 9 is inserted into the inner side of the slot 8. The insert plates 9 are evenly distributed on the inner side of the drill bit 1. A chuck 21 is integrally formed on one side of the insert plate 9. The chuck 21 is located on the outer side of the drill bit 1. Grooves 13 are respectively formed on the inner side of the chuck 21 and the top and bottom of the insert plate 9. The height of the chuck 21 and the insert plate 9 is equal to the spiral spacing of the spiral plate 7. A through hole 14 is formed on the inner side of the insert plate 9. The groove 13 communicates with the slot 9 through the through hole 14. A rubber sleeve 15 is adhered to the inner side of the groove 13. An inner cavity 16 is formed on the inner side of the rubber sleeve 15. The water-absorbing beads 17 are inserted into the inner cavity 16. In use, the drill bit 1 is passed through the spiral plate... 7. The inner side of the drill hole is screwed in. The diameter of the spiral plate 7 is larger than the inner diameter of the drill hole, so that the spiral plate 7 passes through the inner wall of the drill hole and extends to the inner side of the soil layer outside the drill hole until the drill bit 1 is rotated and pushed into the inner side of the drill hole. Hydraulic oil is injected into the inner side of the inner cavity 10 through the oil pipe 11. The hydraulic oil enters the inner side of the slot 8 through the connector 12. The hydraulic pressure pushes the insert plate 9 out of the inner side of the slot 8 and clamps the chuck 21 on the inner wall of the drill hole, or the chuck passes through the inner wall of the drill hole and extends to the inner side of the soil layer outside the drill hole. The spiral plate 7 and the chuck 21 are both inserted into the outer side of the inner wall of the drill hole, thereby effectively preventing the drill bit 1 from moving upward or rotating, ensuring the fixation of the drill bit 1, preventing the drill bit 1 from loosening due to the water pressure at the bottom of the drill hole, and ensuring the fixation of the sealing equipment.

[0044] The support 2 is welded to the top of the drill bit 1, the water injection pipe 5 is welded to the top of the support 2, and the cone 3 is welded to the bottom of the drill bit 1. The water injection chamber 6 is respectively opened inside the support 2, the drill bit 1, and the cone 3. The water injection pipe 5 is connected to the water injection chamber 6. The one-way valve 4 is installed at the bottom of the cone 3 and is sealed at the bottom end of the water injection chamber 6. The chuck 21 and the rubber sleeve 15 are both provided with filter holes 18 on one side. The inner cavity 16 is connected to the outer side of the chuck 21 through the filter holes 18. In use, hydraulic oil enters the inner side of the groove 13 through the through hole 14, squeezing and expanding the rubber sleeve 15 in the groove 13. The rubber sleeve 15 seals the top and bottom of the insert plate 9 to the bottom and top of the spiral plate 7, respectively. At the same time, the rubber sleeve 15 seals the chuck 21 to the inner wall of the borehole. During the water test, high-pressure water is injected downwards into the bottom of the borehole through the water injection pipe 5 and the water injection chamber 6, and the one-way valve 4 is pushed open. After the water pressure flows upwards to the bottom of the drill bit 1, it squeezes the insert rod 9 and the chuck 21 that have moved to the outside of the drill bit 1 along the spiral plate 7 in the opposite direction. The water enters the inner side of the inner cavity 16 through the filter hole 18. The water-absorbing beads 17 in the inner cavity 16 absorb water and expand, further increasing the sealing pressure of the rubber sleeve 15 on the inner wall of the borehole and the spiral plate 7. Even if the water passes through the bottom insert plate 9 and chuck 21 under pressure, multiple sealing units will then perform sealing work, thereby effectively ensuring the sealing effect of the borehole water injection test, avoiding the inability of the sealing device to completely seal the borehole due to unevenness of the inner wall of the borehole, preventing water from penetrating through cracks and capillaries on the inner wall of the borehole, and ensuring the sealing effect of the borehole.

[0045] When using this borehole water injection test sealing device, the drill bit 1 is screwed into the inner side of the borehole through the spiral plate 7. The diameter of the spiral plate 7 is larger than the inner diameter of the borehole, allowing the spiral plate 7 to pass through the inner wall of the borehole and extend to the inner side of the soil layer outside the borehole until the drill bit 1 is rotated and advanced to the inner side of the borehole. Hydraulic oil is injected into the inner side of the inner cavity 10 through the oil pipe 11. The hydraulic oil enters the inner side of the slot 8 through the connector 12. The hydraulic pressure pushes the insert plate 9 out of the inner side of the slot 8 and clamps the chuck 21 onto the inner wall of the borehole, or the chuck passes through the inner wall of the borehole and extends to the inner side of the soil layer outside the borehole. Both the spiral plate 7 and the chuck 21 are inserted into the inner wall of the borehole. On the outside, this effectively prevents the drill bit 1 from moving upwards or rotating, ensuring the drill bit 1's secure fixation and preventing it from loosening due to water pressure at the bottom of the borehole. Hydraulic oil enters the inner side of the groove 13 through the through hole 14, squeezing and expanding the rubber sleeve 15 inside the groove 13. The rubber sleeve 15 seals the top and bottom of the insert plate 9 to the bottom and top of the spiral plate 7, respectively. Simultaneously, the rubber sleeve 15 seals the chuck 21 against the inner wall of the borehole. During the borehole water injection test, high-pressure water is injected downwards into the bottom of the borehole through the water injection pipe 5 and the water injection chamber 6, pushing open the one-way valve 4. The water pressure flows upwards to the drill bit 1. After reaching the bottom, the spiral plate 7 moves in the opposite direction to the insertion rod 9 and chuck 21, which are moved to the outside of the drill bit 1, and squeezes them. Water enters the inner cavity 16 through the filter hole 18. The water-absorbing beads 17 in the inner cavity 16 absorb water and expand, further increasing the sealing pressure of the rubber sleeve 15 on the inner wall of the borehole and the spiral plate 7. Even if water passes through the bottom insertion plate 9 and chuck 21 under pressure, multiple sealing units will then perform sealing work, thereby effectively ensuring the sealing effect of the borehole water injection test. This avoids the sealing device being unable to completely seal the borehole due to unevenness of the inner wall of the borehole, and prevents water from penetrating through cracks and capillaries on the inner wall of the borehole, ensuring the safety of the drill bit. To ensure the sealing effect of the hole, after the experiment is completed, hydraulic oil is extracted through oil pipe 11, and the insert plate 9 is sucked into the inside of the slot 8. The scraper 19 is clamped on both sides of the insert plate 9 or the chuck 21 under the elastic force of the spring 20, and can slide inside the slide groove 22 according to the width change of the insert plate 9 and the chuck 21. The scraper 19 effectively scrapes off the impurities attached to the insert plate 9 and the chuck 21, and avoids the insert plate 9 and the chuck 21 from being unable to retract smoothly into the inside of the slot 8 due to impurities getting stuck inside the slot 8. It also ensures that the drill bit 1 can be quickly moved upward from the inside of the drill hole by the reverse rotation of the spiral plate 7, ensuring the rapid removal of the sealing device.

[0046] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A sealing device for borehole water injection tests, characterized in that, The drill bit (1) includes a support (2) fixedly connected to its top; a water injection pipe (5) and an oil pipe (11) are axially connected through the support (2); a water injection cavity (6) communicating with the water injection pipe (5) is axially connected through the drill bit (1); a spiral plate (7) is fixedly connected to the outer wall of the drill bit (1), the diameter of the spiral plate (7) being larger than the inner diameter of the borehole; an annular cavity (10) is provided around the water injection cavity (6) in the drill bit (1), the annular cavity (10) communicating with the oil pipe (11); several slots (8) are radially symmetrically arranged around the water injection cavity (6) at the lower part of the annular cavity (10) on the drill bit (1), the annular cavity (10) being connected through a connecting port (12). The slots (8) are connected to each other; a plate (9) is movably connected in the slot (8), and a clamp (21) is fixedly connected to one end of the plate (9) facing the outside of the slot (8). A groove (13) is provided in the clamp (21), and a rubber sleeve (15) is provided in the groove (13); a through hole (14) is provided on the plate (9) to connect the groove (13) with the slot (8); when hydraulic oil is injected into the annular cavity (10) through the oil pipe (11), the hydraulic oil enters each slot (8), and the plate (9) is pushed out of the slot (8) by hydraulic pressure. The diameter of the plate (9) when it is completely pushed out of the slot (8) is greater than the inner diameter of the drilled hole. The drill bit (1) has a groove (22) inside, and a spring (20) is installed in the groove (22). One end of the spring (20) is fixed to the wall of the groove (22), and the other end is fixedly connected to a scraper (19). When the spring (20) is in a free state, the scraper (19) contacts the wall of the insert plate (9) at the non-clamping head (21).

2. The borehole water injection test sealing device according to claim 1, characterized in that, The slots (8) are evenly arranged radially around the water injection cavity (6); each layer of the spiral plate (7) has a slot (8) in each spiral spacing.

3. The borehole water injection test sealing device according to claim 1, characterized in that, The rubber sleeve (15) has an inner cavity (16) and a water-absorbing and expanding material is provided in the inner cavity (16). The clip (21) has a filter hole (18) and the inner cavity (16) is connected to the outside through the filter hole (18).

4. The borehole water injection test sealing device according to claim 3, characterized in that, The water-absorbing and swelling material is water-absorbing beads (17).

5. The borehole water injection test sealing device according to claim 1, characterized in that, The card head (21) has two symmetrical grooves (22) on both sides.

6. The borehole water injection test sealing device according to claim 1, characterized in that, The support (2) is fixed to the top of the drill bit (1) by welding, the cone (3) is fixed to the bottom of the drill bit (1) by welding, and a spiral plate (7) is fixedly connected to the outer wall of the drill bit (1) by welding.

7. The borehole water injection test sealing device according to claim 1, characterized in that, The water injection pipe (5) and the oil pipe (11) are both fixed to the support (2) by welding.

8. The borehole water injection test sealing device according to claim 1, characterized in that, The outer diameter of the card head (21) is larger than the outer diameter of the insert plate (9), and the card head (21) and the insert plate (9) are integrally formed.

9. The borehole water injection test sealing device according to claim 1, characterized in that, The top of the drill bit (1) is fixedly connected to a cone (3), and a water injection channel communicating with the water injection chamber (6) is provided on the cone (3). A one-way valve (4) is provided at the outlet of the water injection channel.

10. The borehole water injection test sealing device according to claim 9, characterized in that, The water injection channel is V-shaped, which divides the fluid flowing out of the water injection chamber into two paths and discharges them from the pointed cone (3).

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