Split type oil well anti-jetting device

Abstract

The invention relates to the technical field of blowout preventers, in particular to a split type oil well blowout prevention device which comprises a valve seat, a valve ball and a valve body with an axial channel in the middle. The valve seat is reasonable and compact in structure and convenient to use, the valve body and the valve seat are arranged in a split mode, the valve seat structure is simpler, finish machining can be directly conducted on an inverted taper hole section on the valve seat more conveniently, the machining precision and the surface roughness of the valve seat are effectively improved, the smoothness of a sealing face on the valve seat is higher, and the service life of the valve seat is prolonged. And it is ensured that machining of the sealing face of the inverted conical hole section meets the design requirement, so that the sealing performance between the valve ball and the valve seat is greatly improved, the axial through hole in the valve body is reliably blocked, and underground fluid is prevented from leaking. The valve seat and the valve ball driving assembly are arranged in a split mode, in the daily maintenance process, the valve ball driving assembly can be rapidly detached from the valve body, the valve ball can be taken out to be checked, the abrasion degree of the valve ball is checked, whether a new valve ball is replaced or not is determined, and it is guaranteed that the valve ball and the valve seat can be reliably sealed all the time after the valve ball ascends.

Description

Technical Field

[0001] This invention relates to the field of blowout preventer technology, and is a split-type blowout preventer device for oil wells. Background Technology

[0002] Currently, most oilfields use rod pumps for oil production, and the polished rod is a crucial component of the rod pump pump system. The polished rod passes through the wellhead assembly and packing box, and the entire sucker rod string is suspended from the suspension cable by polished rod clamps. Because the polished rod bears alternating loads and reciprocates up and down during operation, it frequently breaks off. When the polished rod breaks off and falls into the wellbore, the packing box becomes uncontrolled, causing the oil, gas, and water mixture to spray out of the wellhead, resulting in a blowout and posing significant challenges to crude oil production and on-site safety management. Therefore, the safest preventative measure is to install a polished rod breakage blowout preventer (BOP). Specifically, after the polished rod breaks off, the wellhead BOP automatically seals the well, preventing the oil and gas mixture from spraying out and avoiding a blowout.

[0003] Existing wellhead blowout preventers (BOPs) that use a valve ball for sealing work as follows: after the polished rod breaks off and falls into the well, a spring pushes the valve ball into the inverted conical cavity of the BOP. Under the combined action of the buoyancy of the oil-gas-water mixture and the pressure of the wellbore and manifold, the valve ball and the inverted conical cavity abut against each other to form a sealing surface, thus closing the BOP and preventing wellhead blowout and leakage of oil and gas. However, existing wellhead BOPs have the following shortcomings in actual use: the inner cavity of the BOP is prone to rust; the inner cavity where the sealing surface with the valve ball is formed is difficult to machine, and its machining accuracy and surface roughness are difficult to meet the requirements, which can easily lead to poor valve ball sealing; removing the valve ball from the inner cavity of the BOP during calibration is difficult; and the spring is prone to torsion and deformation when adjusting the spring force, affecting the spring's service life. Summary of the Invention

[0004] This invention provides a split-type oil well blowout preventer that overcomes the shortcomings of the prior art. It can effectively solve the problems of existing wellhead blowout preventers, such as the difficulty in machining the sealing surface between the blowout preventer cavity and the valve ball, the difficulty in achieving the required machining accuracy and roughness, the easy occurrence of valve ball not sealing properly, and the difficulty in removing the valve ball from the blowout preventer cavity during the calibration process.

[0005] The technical solution of this invention is achieved through the following measures: a split-type oil well blowout prevention device includes a valve seat, a valve ball, and a valve body with an axial channel in the middle. The valve seat has an axial through hole in the middle for the smooth rod to move up and down reciprocally. The lower part of the valve seat and the upper part of the valve body are detachably installed together. The upper end of the axial channel is connected to the lower end of the axial through hole. The right side of the middle part of the valve body has a valve hole that runs through both the inside and outside. A valve ball drive assembly is detachably installed in the valve hole. The valve ball drive assembly has a valve ball receiving cavity on the inner side of the left part. When the valve ball is squeezed by the smooth rod, it will be retracted into the valve ball receiving cavity. The outer diameter of the valve ball is larger than the inner diameter of the axial through hole but smaller than the inner diameter of the axial channel. When the smooth rod breaks off, the extended end of the valve ball drive assembly can automatically push the valve ball into the axial channel. Under the action of the buoyancy of the downhole fluid and the pressure of the wellbore and the oil gathering pipe manifold, the valve ball moves upward and blocks the axial through hole.

[0006] The following are further optimizations and / or improvements to the above-mentioned technical solution: The aforementioned valve ball drive assembly may include an outer sleeve, an adjusting seat, a drive seat, a compression spring, and a sealing end cap with an opening facing left. The left end of the outer sleeve is fixedly installed to the inside of the valve hole by threads. The adjusting seat is threadedly connected to the inner right side of the outer sleeve, and the adjusting seat has a through-hole in the middle. The drive seat, which can move left and right along its axis, is slidably installed inside the outer sleeve corresponding to the left position of the adjusting seat. The drive seat has a left guide post in the middle of the right side, and the adjusting seat has a right guide ring platform on the left side corresponding to the position of the left guide post. A compression spring is fitted on the outer right side of the right guide ring platform, and the left end of the compression spring is fitted on the outer side of the left guide post. A sealing end cap is detachably installed on the outer right side of the outer sleeve. The cavity on the inner left side of the outer sleeve is the valve ball receiving cavity. When the valve ball is squeezed by the smooth rod, it can push the drive seat to the right to compress the compression spring and retract into the valve ball receiving cavity.

[0007] The inner side of the left end of the outer tube may be provided with a limiting inner ring platform to prevent the drive seat from detaching from the outer tube.

[0008] A thrust bearing, fitted onto the outer side of the right side of the right guide ring platform, can be provided between the right end of the aforementioned compression spring and the left end of the adjusting seat.

[0009] The aforementioned axial through hole may include a straight hole section and an inverted conical hole section connected sequentially from top to bottom. The inner diameter of the straight hole section is adapted to the outer diameter of the polished rod. The inner diameter of the straight hole section is equal to the inner diameter of the upper end of the inverted conical hole section. The inner diameter of the inverted conical hole section increases sequentially from top to bottom. The inner diameter of the upper part of the inverted conical hole section is smaller than the outer diameter of the valve ball. The lower end of the inverted conical hole section is connected to the upper end of the axial channel. After the valve ball passes through the inner side of the upper part of the axial channel and enters the inverted conical hole section, it can abut against the inner side of the upper part of the inverted conical hole section to form a sealing surface.

[0010] The valve body located on the lower side of the aforementioned valve ball drive assembly may be provided with an inner ring platform for receiving the valve ball, the inner diameter of which is adapted to the outer diameter of the polished rod.

[0011] Both the inner surface of the valve body and the inner surface of the valve seat can be treated with nickel-phosphorus plating.

[0012] The above may also include sealing rings, with sealing rings provided between the lower part of the valve seat and the upper part of the valve body, and between the left end of the valve ball drive assembly and the outer side of the middle part of the valve body.

[0013] The valve ball mentioned above can be made of PP material.

[0014] The upper outer side of the valve seat may be provided with external threads, and the lower outer side of the valve seat and the upper inner side of the valve body may be connected together by threads. The lower inner side of the valve seat may be provided with an inner ring groove, and the bottom of the inner ring groove may be provided with internal threads. The lower outer side of the valve seat may have at least two handle mounting holes with outward openings evenly distributed along the circumference, and a rotating handle may be fixedly installed in each handle mounting hole. The middle outer side of the valve body may be provided with a wrench part for easy locking of a wrench.

[0015] This invention features a reasonable and compact structure that is easy to use. It separates the valve body and valve seat, simplifying the valve seat structure and facilitating direct precision machining of the inverted conical bore section. This effectively improves the machining accuracy and surface roughness of the valve seat, resulting in a smoother sealing surface and ensuring that the sealing surface of the inverted conical bore section meets design requirements. This significantly enhances the sealing performance between the valve ball and the valve seat, reliably sealing the axial through-hole on the valve body, preventing downhole fluid leakage, avoiding difficulties in crude oil production and on-site safety management, and reducing the risk of environmental pollution at the well site.

[0016] The valve seat and valve ball drive assembly are set separately. During routine maintenance, the valve ball drive assembly can be quickly removed from the valve body, the valve ball can be taken out for inspection, the wear of the valve ball can be checked, and it can be determined whether a new valve ball needs to be replaced to ensure that the valve ball can always form a reliable seal with the valve seat after it moves upward.

[0017] During use, the assembly of each component of the valve ball drive assembly can be completed in advance. Since both the drive seat and the adjustment seat are made of nylon, which has self-lubricating properties, the adjustment seat can drive the pressure spring and the drive seat to rotate synchronously during the process of rotating the adjustment seat to adjust the pressure spring preload, thereby effectively preventing the pressure spring from tortuous deformation and damage. When assembling the valve ball drive assembly with the valve body, first place the valve ball into the valve hole, then align the assembled valve ball drive assembly with the valve hole, and rotate the valve ball drive assembly to complete the assembly. During the assembly process, when the valve ball abuts against the left end of the drive seat, the valve ball can rotate together with the valve ball drive assembly, which can also effectively prevent the pressure spring from tortuous deformation and greatly extend the service life of the pressure spring.

[0018] The inner surfaces of the valve body and seat are coated with a nickel-phosphorus coating, which gives the inner cavities of the valve body and seat better oxidation resistance, hardness, wear resistance and smoothness, thereby effectively preventing oxidation and corrosion of the inner cavities of the valve body and seat, avoiding rust, greatly extending the service life of the valve body and seat, and making the surface of the parts smoother. Attached Figure Description

[0019] Appendix Figure 1 This is a schematic diagram of the main sectional view of Embodiments 1-10 of the present invention.

[0020] Appendix Figure 2 For the appendix Figure 1 A schematic diagram of the front sectional view of the structure in the state of the broken or detached central beam.

[0021] Appendix Figure 3 For the appendix Figure 1 A schematic diagram of the three-dimensional structure.

[0022] The codes in the attached diagram are as follows: 1 is valve seat, 2 is valve ball, 3 is axial channel, 4 is valve body, 5 is smooth rod, 6 is valve ball receiving cavity, 7 is outer sleeve, 8 is adjusting seat, 9 is drive seat, 10 is compression spring, 11 is sealing end cap, 12 is wrench hole, 13 is left guide post, 14 is right guide ring platform, 15 is limiting inner ring platform, 16 is straight hole section, 17 is inverted conical hole section, 18 is receiving inner ring platform, 19 is sealing ring, 20 is external thread, 21 is inner ring groove, 22 is internal thread, 23 is rotating handle, 24 is wrench part, and 25 is valve hole. Detailed Implementation

[0023] The present invention is not limited to the following embodiments, and the specific implementation can be determined according to the technical solution of the present invention and the actual situation.

[0024] In this invention, for ease of description, the description of the relative positions of the components is based on the appendix to the specification. Figure 1 The layout is described using a diagrammatic method, such as front, back, top, bottom, left, right, etc. The positional relationships are determined based on the layout direction of the attached diagram in the instruction manual.

[0025] The present invention will be further described below with reference to embodiments and accompanying drawings: Example 1: As shown in the attached document Figure 1-3 As shown, the split-type well blowout preventer includes a valve seat 1, a valve ball 2, and a valve body 4 with an axial channel 3 in the middle. The valve seat 1 has an axial through hole in the middle for the smooth rod 5 to move up and down. The lower part of the valve seat 1 and the upper part of the valve body 4 are detachably installed together. The upper end of the axial channel 3 is connected to the lower end of the axial through hole. The valve body 4 has a valve hole 25 with internal and external through holes on the right side of the middle part. A valve ball drive assembly is detachably installed in the valve hole 25. The valve ball drive assembly has a valve ball receiving cavity 6 on the inner left side. When the valve ball 2 is squeezed by the smooth rod 5, it will be retracted into the valve ball receiving cavity 6. The outer diameter of the valve ball 2 is larger than the inner diameter of the axial through hole but smaller than the inner diameter of the axial channel 3. When the smooth rod 5 breaks off, the extended end of the valve ball drive assembly can automatically push the valve ball 2 into the axial channel 3. Under the action of the buoyancy of the downhole fluid and the pressure of the wellbore and the oil gathering pipe manifold, the valve ball 2 moves upward and blocks the axial through hole.

[0026] In the above technical solution, both valve seat 1 and valve body 4 are part of the housing of the oil well blowout prevention device. The separate arrangement of valve seat 1 and valve body 4 simplifies the structure of valve seat 1, making it simpler. This greatly reduces the processing difficulty of valve seat 1, makes it easier to improve the processing accuracy and surface roughness of valve seat 1, and makes the surface finish of the contact position between valve ball 2 and valve seat 1 better. This enhances the sealing effect, allowing valve ball 2 to better form a sealing surface with the inner wall of the lower end of valve seat 1, thereby sealing the axial through hole and preventing the oil, gas and water mixture from being ejected out of the well.

[0027] In this embodiment, the detachable installation between the valve seat 1 and the valve body 4 can be a threaded connection or a rotary snap-fit ​​as in the prior art. To prevent external leakage, a sealing element can be provided between the valve seat 1 and the valve body 4. In order to better seal the axial through hole, the inner side of the lower end of the valve seat 1 can be provided with an inverted conical groove that is smaller at the top and larger at the bottom or a ball-and-socket groove that opens downward, so that after the valve ball 2 floats up, it can form an annular sealing surface with the inverted conical groove or a spherical seal with the ball-and-socket groove.

[0028] During normal operation, the guide rod 5 passes through the axial through hole and axial channel 3. After being squeezed by the guide rod 5, the valve ball 2 will be retracted into the valve ball receiving cavity 6, thus preventing the valve ball 2 from obstructing the up-and-down reciprocating movement of the guide rod 5. As the guide rod 5 moves up and down, under the action of friction, the guide rod 5 can drive the valve ball 2 to rotate in the valve ball receiving cavity 6. Over time, the valve ball 2 will wear down, thus affecting the sealing performance between the valve ball 2 and the valve seat 1. Therefore, the valve ball 2 needs to be removed periodically for calibration. When the wear of the valve ball 2 exceeds the specified threshold, a new valve ball 2 needs to be replaced, and then the new valve ball 2 should be reinstalled into the valve body 4.

[0029] The separate and detachable valve ball drive assembly and valve body 4 make it easier to remove the valve ball 2 for calibration and to clean the inner cavity of the valve ball drive assembly. In this embodiment, the valve ball drive assembly includes a tubular housing, a linear drive mechanism, a pressure detection unit, and a control unit. The left end of the tubular housing and the valve hole 25 are detachably connected by threads. The inner side of the left part of the tubular housing is the valve ball receiving cavity 6. The right part of the tubular housing can be fixedly installed with the linear drive mechanism. The left end of the extended end of the linear actuator can be provided with a pressure detection unit. When the guide rod 5 is working normally, the left end of the valve ball 2 abuts against the outer side of the right part of the guide rod 5, squeezing the valve ball 2, so that most of the ball from the left to the right part of the valve ball 2 is retracted into the valve ball receiving cavity 6. The right end of the valve ball 2 abuts against the pressure detection unit. The control unit can automatically control the operation of the linear actuator according to the detection data of the pressure detection unit and the set threshold. The main control chip of the control unit can be a PLC or an STM32 series. After the guide rod 5 is broken off, the extended end of the linear drive mechanism can extend to the left in the tubular housing, pushing the valve ball 2 to the left into the axial channel 3 in the valve body 4. The linear drive mechanism can be an electric actuator or a gear and rack mechanism driven by a rotary motor, as is the case in the prior art. A pressure sensor is fixedly installed on the left end of the piston rod of the electric actuator or the left end of the rack, and the pressure sensor abuts against the right end of the valve ball 2. When the smooth rod 5 is working normally, the pressure sensor can detect the pressure of the valve ball 2 on it. After the smooth rod 5 is broken off, the left end of the valve ball 2 is unrestrained, and the squeezing force of the valve ball 2 on the pressure sensor will decrease or disappear. The control unit automatically controls the piston rod of the electric actuator to extend to the left, or the rotary motor drives the gear to rotate so that the rack moves to the left, thereby pushing the valve ball 2 into the axial channel 3.

[0030] After the polished rod 5 breaks off, the downhole pressure is much greater than the external pressure, so the downhole fluid can be ejected upwards from the wellhead through the inner cavity of this invention, causing a blowout. When the valve ball 2 is pushed into the axial channel 3, the downhole fluid will generate an upward buoyancy force on the valve body 4. After the pressure of the wellbore and the oil gathering manifold acts on the valve ball 2, the upward axial pressure along the axial channel 3 is much greater than the pressure in other directions. Therefore, under the combined action of the upward buoyancy force and the axial pressure, the valve ball 2 moves upwards along the axial channel 3 until the valve ball 2 forms a sealing surface with the inner wall of the lower end of the valve seat 1, sealing the axial through hole on the valve seat 1, so as to avoid the leakage of oil, gas and water mixture, which would cause difficulties in crude oil production and on-site safety management and pollute the well site environment.

[0031] The separate valve body 4, valve seat 1, and valve ball drive assembly make it easier to commercialize the oil well blowout preventer. When a component of the oil well blowout preventer is damaged, only the more damaged part needs to be replaced, eliminating the need for complete replacement or scrapping, which effectively reduces the cost of using this invention.

[0032] Compared to existing technologies, the valve body 4 and valve seat 1 in this invention are separately configured, making the structure of the valve seat 1 simpler and facilitating direct precision machining of the sealing position on the valve seat 1 with the valve ball 2. This effectively improves the machining accuracy and surface roughness of the valve seat 1, resulting in a smoother sealing surface and ensuring that the machining accuracy of the sealing surface meets design requirements. This significantly improves the sealing performance between the valve ball 2 and the valve seat 1, thereby reliably sealing the axial through hole on the valve body 4, preventing downhole fluid leakage, avoiding difficulties in crude oil production and on-site safety management, and reducing the risk of environmental pollution at the well site. The separate configuration of the valve seat 1 and the valve ball drive assembly allows for quick removal of the valve ball drive assembly from the valve body 4 during routine maintenance. The valve ball 2 can be removed for inspection, and its wear level can be checked to determine whether a new valve ball 2 needs to be replaced, ensuring that the valve ball 2 can always form a reliable seal with the valve seat 1 after it moves upward.

[0033] The above-mentioned split-type oil well blowout preventer can be further optimized and / or improved according to actual needs: Example 2: As shown in the attached document Figure 1-3 As shown, the valve ball drive assembly includes an outer sleeve 7, an adjusting seat 8, a drive seat 9, a compression spring 10, and a sealing end cap 11 with an opening to the left. The left end of the outer sleeve 7 is fixedly installed to the inside of the valve hole 25 by threads. The adjusting seat 8 is connected to the inner right side of the outer sleeve 7 by threads. The adjusting seat 8 has a wrench hole 12 that runs through the left and right sides in the middle. The drive seat 9, which can move left and right along its axis, is slidably installed in the outer sleeve 7 corresponding to the left position of the adjusting seat 8. The drive seat 9 has a left guide post 13 in the middle right side. The adjusting seat 8 has a right guide ring platform 14 on the left side corresponding to the position of the left guide post 13. The compression spring 10 is fitted on the outer right side of the right guide ring platform 14. The left end of the compression spring 10 is fitted on the outer side of the left guide post 13. The sealing end cap 11 is detachably installed on the outer right side of the outer sleeve 7. The cavity on the inner left side of the outer sleeve 7 is the valve ball receiving cavity 6. The valve ball 2 can be pushed to the right by the pressure of the smooth rod 5 to compress the compression spring 10 and move into the valve ball receiving cavity 6.

[0034] During use, first insert the right guide ring 14 into the inner side of the right end of the compression spring 10, then insert the left guide post 13 into the inner side of the left end of the compression spring 10. Under the preload of the spring, the extended end of the valve ball drive assembly can be formed through the drive seat 9 and the compression spring 10. Then, insert the wrench into the wrench hole 12, and then put the drive seat 9 and the compression spring 10 into the outer sleeve 7, and align the outer side of the left end of the adjusting seat 8 with the inner side of the right end of the outer sleeve 7. Then, rotate the adjusting seat 8 with the wrench to tighten and fix the outer side of the adjusting seat 8 to the inner side of the right side of the outer sleeve 7, and adjust their relative positions. Finally, screw the sealing end cap 11 onto the outer side of the right side of the outer sleeve 7 to complete the assembly of the valve ball drive assembly. In its natural state, the left side of the drive seat 9 is located in the valve ball receiving cavity 6. During the above assembly process, the left end of the drive seat 9 is not in any position, so that the drive seat 9 and the compression spring 10 can rotate together with the adjusting seat 8, thereby effectively preventing the compression spring 10 from tortuous deformation.

[0035] During the assembly of the valve ball drive assembly and the valve body 4, the valve ball 2 is first placed into the valve hole 25, and then the left end of the outer sleeve 7 is aligned with the valve hole 25, so that the left end of the drive seat 9 abuts against the right end of the valve ball 2; the outer sleeve 7 is rotated to tighten and fix it in the valve hole 25, at which point the valve ball 2 abuts against the right side of the polished rod 5. During the above installation process, when the valve ball 2 abuts against the left end of the drive seat 9, the valve ball 2 can rotate together with the valve ball drive assembly, thereby effectively preventing the compression spring 10 from tortuous deformation.

[0036] During normal operation, the guide rod 5 moves up and down in the axial through hole. The valve ball 2 is constrained by the valve ball receiving cavity 6 and cannot move up and down. However, under the action of friction, the valve ball 2 can only rotate between the guide rod 5 and the drive seat 9 as the guide rod 5 moves back and forth, without affecting the normal operation of the guide rod 5.

[0037] When the polished rod 5 breaks off, the valve ball 2 is pushed to the left into the axial channel 3 by the drive seat 9 under the restoring force of the compression spring 10. The valve ball 2 in the axial channel 3 will be subjected to the combined action of the buoyancy of the outward gushing downhole fluid and the pressure of the wellbore and oil gathering manifold. The buoyancy is upward and the upward pressure of the wellbore and oil gathering manifold is much greater than the pressure in other directions, so that the valve ball 2 can float up and block the axial through hole.

[0038] Depending on the requirements, the shape of the wrench hole 12 can be straight, cross-shaped, or hexagonal to increase the contact area with the wrench. The shape of the inner side of the right guide ring is adapted to the shape of the wrench hole 12. To facilitate the disassembly and assembly of the valve ball drive assembly, the outer side of the outer sleeve 7 and the outer side of the sealing end cover 11 are provided with wrench grooves or wrench holders to facilitate wrench engagement. The cross-sectional shape of the wrench groove or wrench holder can be drum-shaped, square, or hexagonal, and a manual rotating handle can also be provided.

[0039] Example 3: As shown in the attached document Figure 1-2As shown, the inner side of the left end of the outer tube 7 is provided with a limiting inner ring platform 15 to prevent the drive seat 9 from disengaging from the outer tube 7.

[0040] With this setting, the inner ring platform 15 can limit the stroke of the drive seat 9, effectively preventing the drive seat 9 and the compression spring 10 from coming out of the outer sleeve 7, and avoiding the loss or falling of the drive seat 9 into the well.

[0041] During use, after assembling the drive seat 9, compression spring 10, and adjusting seat 8, the extended end of the valve ball drive assembly can be formed by the drive seat 9 and compression spring 10 under the action of spring preload. After the components of the valve ball drive assembly are assembled, the left part of the drive seat 9 is located in the valve ball receiving cavity 6, and the left end of the drive seat 9 abuts against the right side wall of the limiting inner ring platform 15. In this embodiment, both the drive seat 9 and the adjusting seat 8 are made of nylon engineering plastic. Nylon engineering plastic has good heat resistance, wear resistance, and self-lubricating properties, so the weight of the extended end is much lighter than that of metal components. The left end of the drive seat 9 and the limiting inner ring platform 15 can self-lubricate. When the adjusting seat 8 is turned, the adjusting seat 8 can drive the compression spring 10 and the drive seat 9 to rotate together. During this process, the drive seat 9 can rotate smoothly on the right side wall of the limiting inner ring platform 15 without jamming, thereby effectively preventing the compression spring 10 from being torsional and deformed, affecting its working performance and service life.

[0042] In addition, during the rotation of the adjusting seat 8, since the nylon adjusting seat 8 has self-lubricating properties, the right end of the compression spring 10 can also rotate relative to the adjusting seat 8, thereby further preventing the compression spring 10 from tortuous deformation.

[0043] Example 4: A thrust bearing is provided between the right end of the compression spring 10 and the left end of the adjusting seat 8, which is fitted on the outer side of the right guide ring platform 14.

[0044] With this configuration, after the valve ball 2 and the valve ball drive assembly are installed on the valve body 4, when it is necessary to fine-tune the spring preload, the thrust bearing can separate the pressure spring 10 from the adjusting seat 8, allowing the adjusting seat 8 to rotate independently while the pressure spring 10 remains fixed. Thus, the pressure spring 10 can be quickly adjusted without disassembling the valve ball drive assembly, greatly saving adjustment time.

[0045] Example 5: As shown in the attached document Figure 1-2 As shown, the axial through hole includes a straight hole section 16 and an inverted conical hole section 17 connected sequentially from top to bottom. The inner diameter of the straight hole section 16 is adapted to the outer diameter of the smooth rod 5. The inner diameter of the straight hole section 16 is equal to the inner diameter of the upper end of the inverted conical hole section 17. The inner diameter of the inverted conical hole section 17 increases sequentially from top to bottom. The inner diameter of the upper part of the inverted conical hole section 17 is smaller than the outer diameter of the valve ball 2. The lower end of the inverted conical hole section 17 is connected to the upper end of the axial channel 3. After the valve ball 2 passes through the upper inner side of the axial channel 3 and enters the inverted conical hole section 17, it can abut against the upper inner side of the inverted conical hole section 17 to form a sealing surface.

[0046] During use, the straight hole section 16 located on the inner side of the upper end of the valve seat 1 can provide guide support for the reciprocating up and down movement of the smooth rod 5; the inverted conical hole section 17 can ensure that an annular sealing surface is formed between the valve ball 2 and the inner cavity of the valve seat 1, which has a reliable sealing effect and is more suitable for high pressure environments; in addition, the upper part of the inverted conical hole section 17 first contacts the valve ball 2 to form a sealing surface. As the usage time increases, when the inner diameter of the contact position between the upper part of the inverted conical hole section 17 and the valve ball 2 wears and becomes larger, the valve ball 2 can still achieve sealing after slightly moving upward, effectively extending the service life of the invention.

[0047] With the valve body 4 and valve seat 1 designed separately, the lower end of the inverted conical hole section 17 is open and will not be obstructed by the valve body 4, thus simplifying the machining process. The machining of the single inverted conical hole section 17 is a mature process in the existing technology, which can effectively improve the machining accuracy and surface roughness of the inverted conical hole section 17. It is also more convenient to further improve the machining accuracy of the inverted conical hole section 17 through finishing methods such as grinding, thereby enhancing the sealing between the inverted conical hole section 17 and the valve ball 2.

[0048] Example 6: As shown in the appendix Figure 1-2 As shown, the valve body 4, located on the lower side of the valve ball drive assembly, is provided with an inner ring platform 18 for receiving the valve ball 2. The inner diameter of the inner ring platform 18 is adapted to the outer diameter of the smooth rod 5.

[0049] During use, when the valve ball 2 falls back, the inner ring support 18 can catch the falling valve ball 2, preventing it from falling into the well and becoming a "fish in the ground," thus avoiding valve ball 2 retrieval operations and reducing operating costs. The inner ring support 18 can also be used to support the polished rod 5 and guide it. Depending on the requirements, the inner diameter of the inner ring support 18 is smaller than the outer diameter of the valve ball 2.

[0050] When replacing the new polished rod 5, the valve seat 1 and valve body 4 can be disassembled, and the valve ball 2 can be quickly removed from the valve body 4, so that the axial channel 3 and the axial through hole can be reconnected, providing installation space for the new polished rod 5. This can greatly improve the efficiency of the polished rod 5 replacement operation and save operation time. After the valve ball 2 passes the inspection, it can still be reused, further saving on usage costs.

[0051] Example 7: The inner sides of the valve body 4 and the valve seat 1 are both treated with nickel-phosphorus plating.

[0052] With this setup, after nickel-phosphorus plating, a uniform coating can be formed on the inner surfaces of the valve body 4 and valve seat 1. The nickel-phosphorus coating has good oxidation resistance, which can effectively prevent oxidation corrosion of the inner surfaces of the valve body 4 and valve seat 1. The nickel-phosphorus hardness coating can also significantly improve the hardness and wear resistance of the inner surfaces of the valve body 4 and valve seat 1, extending the service life of the valve body 4 and valve seat 1. It can also make the inner surfaces of the valve body 4 and ball seat have good smoothness and flatness, and the surface of the parts is smoother.

[0053] Example 8: As attached Figure 1-2 As shown, it also includes a sealing ring 19, which is provided between the lower part of the valve seat 1 and the upper part of the valve body 4, and between the left end of the valve ball drive assembly and the outer side of the middle part of the valve body 4.

[0054] This design effectively seals the gaps at the connection between valve seat 1 and valve body 4, and at the connection between valve ball drive assembly and valve body 4, ensuring the sealing of the connections between various components and preventing fluid leakage from the valve.

[0055] Example 9: Valve ball 2 is made of PP material.

[0056] This design allows the valve ball 2 to have advantages such as good toughness, light weight, and strong impact resistance, making it easier for the valve ball 2 to float up under the buoyancy of the downhole fluid and the pressure of the wellbore and oil gathering pipe manifold, and form a seal with the upper inner side of the inverted cone section 17, sealing the axial through hole in the valve seat 1 and preventing blowout.

[0057] Example 10: As attached Figure 1-2 As shown, the upper outer side of the valve seat 1 is provided with an external thread 20, and the lower outer side of the valve seat 1 is connected to the upper inner side of the valve body 4 by a thread. The lower inner side of the valve body 4 is provided with an inner ring groove 21, and the bottom of the inner ring groove 21 is provided with an internal thread 22. The lower outer side of the valve seat 1 is evenly distributed with at least two handle mounting holes with outward openings along the circumference, and a rotating handle 23 is fixedly installed in each handle mounting hole. The middle outer side of the valve body 4 is provided with a wrench part 24 for easy locking of a wrench.

[0058] In this embodiment, the external thread 20 on the upper part of the valve seat 1 can be used to connect with a packing seal box in the prior art. The internal thread 22 on the lower part of the valve seat 1 can be used to connect with a rubber gate valve in the prior art. The rubber gate valve in the prior art is one of the wellhead accessories commonly used in rod pump wells, and has the function of opening and closing the wellhead of the oil well.

[0059] Therefore, during routine maintenance, after closing the rubber gate, the valve ball drive assembly can be removed from the valve body 4 to quickly check the wear condition of the valve ball 2. When the wear of the valve ball 2 exceeds the specified threshold, a new valve ball 2 can be replaced, and the valve ball drive assembly can be reinstalled in its original position to save maintenance time and ensure that the valve ball 2 always has reliable sealing performance.

[0060] During use, the valve body 4 and valve seat 1, which are connected by threads, can be disassembled and maintained using existing wrench tools. During processing, the split design makes it easier to perform fine machining on the inner surface of the valve seat 1 that contacts the valve ball 2, such as grinding and polishing, to ensure a reliable seal between the valve ball 2 and the upper inner side of the inverted conical hole section 17, preventing the leakage of downhole fluid.

[0061] Without using a wrench, the valve seat 1 can be quickly rotated by turning the handle 23, thus enabling the valve seat 1 to be disassembled and assembled. The fixed installation between the handle and the handle mounting hole can be a detachable installation such as a threaded connection or a snap-fit, or a non-detachable installation such as an interference fit or an adhesive fit.

[0062] Depending on the requirements, the wrench part 24 can be a wrench groove or wrench holder with a cross-section that is drum-shaped, square or hexagonal in the prior art. In this embodiment, it is a square wrench holder.

[0063] The method of using this invention can be described as follows: After the valve body 4 and the valve seat 1 are installed together, the present invention can be installed between the packing box and the rubber gate at the wellhead, so that the smooth rod 5 can pass through the sealed inner cavity of the packing box, the axial through hole, the axial channel 3 and the inner cavity of the rubber gate from top to bottom.

[0064] After inserting the right guide ring 14 into the inner side of the right end of the compression spring 10, insert the left guide post 13 into the inner side of the left end of the compression spring 10 to complete the assembly of the drive seat 9, the compression spring 10 and the adjusting seat 8. After inserting the wrench into the wrench hole 12, first put the drive seat 9 and the compression spring 10 into the outer sleeve 7, and then align the outer side of the left end of the adjusting seat 8 with the inner side of the right end of the outer sleeve 7. Rotate the adjusting seat 8 with the wrench to tighten and fix the outer side of the adjusting seat 8 to the inner side of the right side of the outer sleeve 7, and screw the adjusting seat 8 into the predetermined length so that the preload of the compression spring 10 reaches the predetermined requirement. Finally, screw the sealing end cap 11 onto the outer side of the right side of the outer sleeve 7 to complete the assembly of the valve ball drive assembly.

[0065] Place the valve ball 2 into the valve hole 25, align the left end of the outer sleeve 7 with the valve hole 25, and make the left end of the drive seat 9 abut against the right end of the valve ball 2; rotate the outer sleeve 7 to tighten and fix it in the valve hole 25, so that the left end of the valve ball 2 abuts against the right side of the smooth rod 5, and the assembly of the valve ball drive assembly and the valve body 4 is completed.

[0066] During normal operation, the guide rod 5 moves up and down reciprocally within the axial channel 3. The valve ball 2 is constrained by the valve ball receiving cavity 6 and cannot move up and down significantly. However, under the action of friction, the valve ball 2 can roll and rotate between the guide rod 5 and the drive seat 9 as the guide rod 5 moves back and forth, without affecting the normal operation of the guide rod 5.

[0067] During routine maintenance, close the rubber gate, remove the valve ball drive assembly from the valve body 4, take out the valve ball 2, and check whether the wear of the valve ball exceeds the specified threshold to determine whether the valve ball 2 needs to be replaced with a new valve ball 2. After the check is completed, put the valve ball 2 (or a new valve ball) back into the valve hole 25, and fix the valve ball drive assembly to the valve body 4 again.

[0068] When the polished rod 5 breaks off, under the restoring force of the compression spring 10, the compression spring 10 pushes the drive seat 9 to slide to the left to reset, and the valve ball 2 is pushed to the left into the axial channel 3 by the drive seat 9; under the combined action of the buoyancy of the downhole fluid and the pressure of the wellbore and oil gathering manifold, the valve ball 2 floats up and blocks the inner side of the upper part of the inverted conical section 17; among them, the direction of buoyancy is upward, and the upward pressure of the wellbore and oil gathering manifold on the valve ball 2 is much greater than the pressure in other directions.

[0069] When replacing the polished rod 5, close the rubber gate. The steel ball falls back and is caught by the inner ring platform 18. Remove the valve seat 1 from the valve body 4, and then remove the valve ball 2. Reconnect the axial through hole and the axial channel 3, and reinstall the valve seat 1 and the valve body 4 together. Then, pass the new polished rod 5 from top to bottom through the sealing cavity of the packing box, the axial through hole, the axial channel 3, and the inner cavity of the rubber gate. Remove the valve ball drive assembly, first reinstall the valve ball 2 into the valve hole 25, and then reinstall the valve ball drive assembly back onto the valve body 4.

[0070] This invention features a reasonable and compact structure that is easy to use. By separating the valve body 4 and the valve seat 1, the structure of the valve seat 1 becomes simpler, and it is easier to directly perform precision machining on the inverted conical hole section 17 on the valve seat 1. This effectively improves the machining accuracy and surface roughness of the valve seat 1, resulting in a smoother sealing surface. This ensures that the machining of the sealing surface of the inverted conical hole section 17 meets the design requirements, thereby greatly improving the sealing performance between the valve ball 2 and the valve seat 1. This reliably seals the axial through hole on the valve body 4, preventing downhole fluid leakage, avoiding difficulties in crude oil production and on-site safety management, and reducing the risk of environmental pollution at the well site.

[0071] The valve seat 1 and the valve ball drive assembly are set separately. During routine maintenance, the valve ball drive assembly can be quickly removed from the valve body 4, and the valve ball 2 can be taken out for verification. The wear of the valve ball 2 can be checked to determine whether a new valve ball 2 needs to be replaced, so as to ensure that the valve ball 2 can always form a reliable seal with the valve seat 1 after it moves upward.

[0072] During use, the assembly of each component of the valve ball drive assembly can be completed in advance. Since the drive seat 9 and the adjusting seat 8 are both made of nylon, which has self-lubricating properties, the adjusting seat 8 can drive the pressure spring 10 and the drive seat 9 to rotate synchronously during the process of rotating the adjusting seat 8 to adjust the preload of the pressure spring 10. This effectively prevents the pressure spring 10 from being torsional and deformed, thus preventing damage to the pressure spring 10. When assembling the valve ball drive assembly with the valve body 4, first place the valve ball 2 into the valve hole 25, then align the assembled valve ball drive assembly with the valve hole 25, and rotate the valve ball drive assembly to complete the assembly. During the assembly process, when the valve ball 2 abuts against the left end of the drive seat 9, the valve ball 2 can rotate together with the valve ball drive assembly, which can also effectively prevent the pressure spring 10 from being torsional and deformed, greatly extending the service life of the pressure spring 10.

[0073] The inner surfaces of the valve body 4 and valve seat 1 are coated with a nickel-phosphorus coating, which gives the inner cavities of the valve body 4 and valve seat 1 better oxidation resistance, hardness, wear resistance and smoothness, thereby effectively preventing oxidation corrosion of the inner cavities of the valve body 4 and valve seat 1, avoiding rust, greatly extending the service life of the valve body 4 and valve seat 1, and making the surface of the parts smoother.

[0074] The above technical features constitute various embodiments of the present invention, which have strong adaptability and implementation effect. Unnecessary technical features can be added or removed according to actual needs to meet the needs of different situations.

Claims

1. A split-type oil well blowout prevention device, characterized in that... The valve includes a valve seat, a valve ball, and a valve body with an axial channel in the middle. The valve seat has an axial through hole in the middle for the smooth rod to move up and down. The lower part of the valve seat and the upper part of the valve body are detachably installed together. The upper end of the axial channel is connected to the lower end of the axial through hole. The right side of the middle part of the valve body has a valve hole that runs through both the inside and outside. A valve ball drive assembly is detachably installed in the valve hole. The valve ball drive assembly has a valve ball receiving cavity on the inner left side. When the valve ball is squeezed by the smooth rod, it will be retracted into the valve ball receiving cavity. The outer diameter of the valve ball is larger than the inner diameter of the axial through hole but smaller than the inner diameter of the axial channel. When the smooth rod breaks off, the extended end of the valve ball drive assembly can automatically push the valve ball into the axial channel. Under the action of the buoyancy of the downhole fluid and the pressure of the wellbore and oil gathering manifold, the valve ball moves upward and blocks the axial through hole.

2. The split-type oil well blowout prevention device according to claim 1, characterized in that, The valve ball drive assembly includes an outer tube, an adjusting seat, a drive seat, a compression spring, and a sealing end cap with an opening to the left. The left end of the outer tube is fixedly installed to the inside of the valve hole by threads. The adjusting seat is threaded to the inner right side of the outer tube, and the adjusting seat has a through-hole in the middle. The drive seat, which can move left and right along its axis, is slidably installed inside the outer tube corresponding to the left position of the adjusting seat. The drive seat has a left guide post in the middle of the right side, and the adjusting seat has a right guide ring platform on the left side corresponding to the position of the left guide post. A compression spring is fitted on the outer right side of the right guide ring platform, and the left end of the compression spring is fitted on the outer side of the left guide post. A sealing end cap is detachably installed on the outer right side of the outer tube. The cavity inside the left side of the outer tube is the valve ball receiving cavity. When the valve ball is squeezed by the smooth rod, it can push the drive seat to the right to compress the compression spring and retract into the valve ball receiving cavity.

3. The split-type oil well blowout prevention device according to claim 2, characterized in that, The inner side of the left end of the outer tube is provided with a limiting inner ring platform to prevent the drive seat from detaching from the outer tube; Or / and, a thrust bearing is provided between the right end of the compression spring and the left end of the adjusting seat, which is fitted on the outer side of the right guide ring platform.

4. The split-type oil well blowout prevention device according to claim 1, 2, or 3, characterized in that, The axial through hole includes a straight hole section and an inverted conical hole section connected sequentially from top to bottom. The inner diameter of the straight hole section is adapted to the outer diameter of the polished rod. The inner diameter of the straight hole section is equal to the inner diameter of the upper end of the inverted conical hole section. The inner diameter of the inverted conical hole section increases sequentially from top to bottom. The inner diameter of the upper part of the inverted conical hole section is smaller than the outer diameter of the valve ball. The lower end of the inverted conical hole section is connected to the upper end of the axial channel. After the valve ball passes through the inner side of the upper part of the axial channel and enters the inverted conical hole section, it can abut against the inner side of the upper part of the inverted conical hole section to form a sealing surface.

5. The split-type oil well blowout prevention device according to claim 1, 2, or 3, characterized in that, The valve body located on the lower side of the valve ball drive assembly is provided with a receiving inner ring platform for receiving the valve ball, and the inner diameter of the receiving inner ring platform is adapted to the outer diameter of the polished rod. Or / and, both the inner surface of the valve body and the inner surface of the valve seat are treated with nickel-phosphorus plating.

6. The split-type oil well blowout prevention device according to claim 4, characterized in that, The valve body located on the lower side of the valve ball drive assembly is provided with a receiving inner ring platform for receiving the valve ball, and the inner diameter of the receiving inner ring platform is adapted to the outer diameter of the polished rod. Or / and, both the inner surface of the valve body and the inner surface of the valve seat are treated with nickel-phosphorus plating.

7. The split-type oil well blowout prevention device according to claim 1, 2, 3, or 6, characterized in that, It also includes sealing rings, with sealing rings provided between the lower part of the valve seat and the upper part of the valve body, and between the left end of the valve ball drive assembly and the outer side of the middle of the valve body; Or / and, the valve ball is made of PP material.

8. The split-type oil well blowout prevention device according to claim 4, characterized in that, It also includes sealing rings, with sealing rings provided between the lower part of the valve seat and the upper part of the valve body, and between the left end of the valve ball drive assembly and the outer side of the middle of the valve body; Or / and, the valve ball is made of PP material.

9. The split-type oil well blowout prevention device according to claim 5, characterized in that, It also includes sealing rings, with sealing rings provided between the lower part of the valve seat and the upper part of the valve body, and between the left end of the valve ball drive assembly and the outer side of the middle of the valve body; Or / and, the valve ball is made of PP material.

10. The split-type oil well blowout prevention device according to any one of claims 1 to 9, characterized in that, The upper outer side of the valve seat is provided with external threads, and the lower outer side of the valve seat is connected to the upper inner side of the valve body by threads. The lower inner side of the valve body is provided with an inner ring groove, and the bottom of the inner ring groove is provided with internal threads. The lower outer side of the valve seat has at least two handle mounting holes with outward openings evenly distributed along the circumference, and a rotating handle is fixedly installed in each handle mounting hole. The middle outer side of the valve body is provided with a wrench part for easy locking of a wrench.

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