A kelly cock valve with a floating valve seat for use in oil field operations

Abstract

The present application relates to the technical field of plug valves, and discloses a kelly plug valve with a floating valve seat for oilfield development, which comprises a plug valve body, a ball valve is rotationally arranged at the central position inside the plug valve body, upper valve seats and lower valve seats are arranged on the two sides of the ball valve, and the upper valve seats and the lower valve seats are both axially floatingly matched with the inner wall of the plug valve body; a state indicating ring is fixedly arranged on the outer wall of each of the upper valve seats and the lower valve seats, and the two state indicating rings are axially floatingly synchronized with the corresponding upper valve seats and lower valve seats; an outer measuring module is fixedly installed on the outer wall of the plug valve body, and a plurality of non-contact linear displacement sensors are integrally arranged in the outer measuring module; the upper valve seats and the lower valve seats are axially floatingly arranged, and the state indicating rings are fixedly arranged on the outer walls of the upper valve seats and the lower valve seats, the non-contact linear displacement sensors in the outer measuring module are used to collect the axial displacement of the state indicating rings in real time, and the wear degree of the valve seats can be directly reflected.

Description

Technical Field

[0001] This invention relates to the field of plug valves, and more specifically, to a square drill pipe plug valve with a floating seat for oilfield development. Background Technology

[0002] Square drill pipe plug valves are important safety control devices in oil drilling operations, used to quickly cut off or connect drilling fluid circulation channels during drilling to prevent blowout accidents. In oilfield development, especially in the exploration and development of deep, ultra-deep, and unconventional oil and gas resources, drilling operations face increasingly complex and demanding working conditions.

[0003] During long-term use, the drilling fluid contains a large number of abrasive particles from the formation, such as quartz sand and rock cuttings. Combined with the continuous scouring of high-pressure, high-speed fluids, the valve seat sealing surface inevitably undergoes gradual wear, leading to decreased sealing performance and even leakage. This is especially true when drilling into high-pressure oil and gas layers, where frequent throttling and kill operations, as well as highly corrosive drilling fluids containing acidic media such as hydrogen sulfide, drastically accelerate the corrosion and wear of the valve seat sealing surface. Well blowouts are one of the most serious and devastating catastrophic accidents in drilling operations, and the plug valve, as a critical line of defense in the well control system, directly impacts well control safety in terms of its reliability. However, current technology lacks an effective means to monitor valve seat wear in real time and accurately. Typically, valve seat wear can only be detected through periodic shutdowns, disassembly and inspection, or after a leak occurs. This reactive or periodic maintenance model not only significantly increases maintenance costs and valuable drilling downtime but also creates a significant safety hazard of sudden seal failure during critical drilling phases. Therefore, we propose a square drill pipe plug valve with a floating seat for oilfield development. Summary of the Invention

[0004] This invention provides a square drill pipe plug valve with a floating valve seat for oilfield development, which solves the technical problem that valve seat wear can only be detected through periodic shutdown inspections or after a leak occurs in related technologies. This not only increases maintenance costs and downtime, but may also bring safety hazards.

[0005] This invention provides a square drill pipe plug valve with floating valve seat for oilfield development, comprising: a plug valve body, a ball valve rotatably disposed at the center of the plug valve body, an upper valve seat and a lower valve seat respectively disposed on both sides of the ball valve, and the upper valve seat and the lower valve seat forming an axial floating fit structure with the inner wall of the plug valve body; Status indicator rings are fixedly installed on the outer walls of the upper valve seat and the lower valve seat. The two status indicator rings float synchronously axially with their respective upper and lower valve seats. An external measurement module is fixedly installed on the outer wall of the plug valve body. Multiple non-contact linear displacement sensors are integrated in the external measurement module. Each linear displacement sensor forms a radially opposed monitoring cooperation with the corresponding status indicator ring. The external measurement module collects the axial displacement of the status indicator ring in real time through a linear displacement sensor, and determines the wear status and axial floating trend of the upper and lower valve seats based on a preset displacement threshold.

[0006] Furthermore, both the upper and lower valve seats have a locking groove and two annular grooves on their outer walls. The status indicator ring is fixed in the locking groove, and the two annular grooves are equipped with seals for sealing the upper and lower valve seats with the inner wall of the plug valve body.

[0007] Furthermore, the status indicator ring is a high-magnetic permalloy ring, which floats together with the valve seat. The sensor signal line of the external measurement module is led out through the connector line and connected to the external signal processing unit.

[0008] Furthermore, both the upper and lower valve seats have spring holes arranged on the side away from the ball valve. A push spring is fixedly installed in the spring hole. The push spring on the side of the lower valve seat directly pushes against the side wall inside the plug valve body, constantly pushing the lower valve seat to apply a thrust towards the ball valve.

[0009] Furthermore, a retaining ring is provided on the side of the upper valve seat near the thrust spring. All the thrust springs on the side of the upper valve seat push against the retaining ring, always applying a pushing force towards the ball valve to the upper valve seat.

[0010] Furthermore, both the upper and lower valve seats are supported by multiple thrust springs, enabling the ball valve to achieve bidirectional hard contact sealing with the sealing surfaces of the upper and lower valve seats. The initial seal is reliable, and the seal is maintained under pressure. The ball valve surface is plated with hard chrome.

[0011] Furthermore, the upper and lower valve seats and the sealing surface of the ball valve are provided with concealed grooves, and a magnetic ball is slidably arranged inside the concealed groove. A push ball spring is provided on one side of the magnetic ball, and the push ball spring always pushes the magnetic ball to move towards the ball valve.

[0012] Furthermore, the ball valve surface has a block array corresponding to the position of the concealed groove chamber, and a magnetic block is set inside the block. The magnetic block and the magnetic ball repel each other. The magnetic forces of several magnetic blocks are different. When the ball valve is rotated to different positions, the magnetic blocks with different magnetic forces push the magnetic ball to a different displacement.

[0013] Furthermore, one of the multiple linear displacement sensors in the external measurement module corresponds to the position of the magnetic ball, detecting the displacement amplitude of the magnetic ball. AI data analysis is used to determine the state of the ball valve. Multiple indicator lights are set on the outer wall of the external measurement module housing, and different lights illuminate depending on the state of the ball valve.

[0014] Furthermore, a knob for controlling the rotation of the ball valve is provided at the center of the outer wall of the plug valve body.

[0015] The beneficial effects of this invention are as follows: This invention sets up an axially floating upper valve seat and a lower valve seat, and fixes a status indicator ring on their outer wall. The non-contact linear displacement sensor in the external measurement module collects the axial displacement of the status indicator ring in real time, which can directly reflect the wear degree of the valve seat. Based on the preset displacement threshold, the wear state and axial floating trend of the valve seat can be accurately determined, thereby realizing real-time and online monitoring of valve seat wear, avoiding the drawbacks of traditional shutdown inspection, and significantly improving the safety of equipment operation. The floating seat design allows the valve seat to better adapt to the wear and deformation of the ball valve, maintaining a tight contact with the ball valve at all times, thereby improving sealing performance. Real-time monitoring of wear status allows for timely maintenance or replacement, preventing leakage due to excessive wear and extending the overall service life of the plug valve. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a schematic diagram of the internal structure of the plug valve body of the present invention; Figure 3 This is a schematic diagram of the upper valve seat structure of the present invention; Figure 4 This is a schematic diagram of the ball valve structure of the present invention; Figure 5 This is the invention Figure 4 Enlarged view of point A in the middle; Figure 6 This is a schematic diagram of the upper valve seat structure from the left.

[0017] In the diagram: 11. Plug valve body; 12. Ball valve; 13. Knob; 14. Upper valve seat; 15. Lower valve seat; 16. Ring groove; 17. Spring hole; 18. Thrust spring; 21. Snap ring; 22. Locking groove; 23. Status indicator ring; 24. Block; 25. Magnetic block; 26. Concealed groove chamber; 27. Push ball spring; 28. Magnetic ball; 29. ​​Seal; 3. External measurement module; 31. Indicator light. Detailed Implementation

[0018] The subject matter described herein will now be discussed with reference to exemplary embodiments. It should be understood that these embodiments are discussed only to enable those skilled in the art to better understand and implement the subject matter described herein, and changes may be made to the function and arrangement of the elements discussed without departing from the scope of this specification. Various processes or components may be omitted, substituted, or added as needed in the examples. Furthermore, features described in some examples may be combined in other examples.

[0019] like Figures 1-6 As shown, an oilfield development square drill pipe plug valve with floating valve seat includes: a plug valve body 11, a ball valve 12 rotatably disposed at the center position inside the plug valve body 11, an upper valve seat 14 and a lower valve seat 15 respectively disposed on both sides of the ball valve 12, and the upper valve seat 14 and the lower valve seat 15 forming an axial floating fit structure with the inner wall of the plug valve body 11. Status indicator rings 23 are fixedly provided on the outer walls of the upper valve seat 14 and the lower valve seat 15. The two status indicator rings 23 float synchronously axially with their respective upper valve seat 14 and lower valve seat 15. An external measuring module 3 is fixedly installed on the outer wall of the plug valve body 11. Multiple non-contact linear displacement sensors are integrated in the external measuring module 3. Each linear displacement sensor forms a radially opposed monitoring cooperation with the corresponding status indicator ring 23. The external measurement module 3 collects the axial displacement of the status indicator ring 23 in real time through a linear displacement sensor, and determines the wear status and axial floating trend of the upper valve seat 14 and the lower valve seat 15 based on a preset displacement threshold.

[0020] Both the upper valve seat 14 and the lower valve seat 15 have a locking groove 22 and two annular grooves 16 on their outer walls. The status indicator ring 23 is fixed in the locking groove 22. Both annular grooves 16 are provided with sealing elements 29 for sealing the upper valve seat 14 and the lower valve seat 15 with the inner wall of the plug valve body 11.

[0021] The status indicator ring 23 is a high-magnetic permalloy ring. The status indicator ring 23 floats together with the valve seat. The sensor signal line of the external measurement module 3 is led out through the connector line and connected to the external signal processing unit.

[0022] Both the upper valve seat 14 and the lower valve seat 15 have spring holes 17 arranged on the side away from the ball valve 12. A push spring 18 is fixedly installed in the spring hole 17. The push spring 18 on the side of the lower valve seat 15 directly pushes against the side wall inside the plug valve body 11, and always pushes the lower valve seat 15 to apply a thrust towards the ball valve 12.

[0023] A retaining ring 21 is provided on the side of the upper valve seat 14 near the thrust spring 18. All the thrust springs 18 on the side of the upper valve seat 14 push against the retaining ring 21, and always apply a pushing force to the upper valve seat 14 in the direction of the ball valve 12.

[0024] Furthermore, both the upper valve seat 14 and the lower valve seat 15 are supported by multiple thrust springs 18 to ensure bidirectional hard contact sealing between the ball valve 12 and the sealing surfaces of the upper valve seat 14 and the lower valve seat 15. The initial seal is reliable and the seal is guaranteed under pressure. The surface of the ball valve 12 is plated with hard chrome.

[0025] The upper valve seat 14 and the lower valve seat 15 are provided with a concealed groove 26 inside the sealing surface with the ball valve 12. A magnetic ball 28 is slidably arranged inside the concealed groove 26, and a push ball spring 27 is provided on one side of the magnetic ball 28. The push ball spring 27 always pushes the magnetic ball 28 to move towards the ball valve 12.

[0026] The ball valve 12 has a block 24 arrayed on the surface corresponding to the position of the concealed groove 26. The block 24 has a magnetic block 25 inside. The magnetic block 25 and the magnetic ball 28 repel each other. The magnetic forces of the several magnetic blocks 25 are different. When the ball valve 12 is rotated to different positions, the magnetic blocks 25 with different magnetic forces push the magnetic ball 28 to a different displacement.

[0027] One of the multiple linear displacement sensors in the external measurement module 3 corresponds to the position of the magnetic ball 28, detecting the displacement amplitude of the magnetic ball 28. The AI ​​data analysis determines the state of the ball valve 12. Multiple indicator lights 31 are set on the outer wall of the housing of the external measurement module 3. The lights illuminate differently depending on the state of the ball valve 12.

[0028] A knob 13 for controlling the rotation of ball valve 12 is provided at the center of the outer wall of the plug valve body 11.

[0029] The working principle revolves around two core elements: "floating seal" and "intelligent monitoring," as detailed below: Initial pre-sealing and pressure adaptive sealing: Initial sealing: Under the preload of multiple thrust springs 18, the upper valve seat 14 and lower valve seat 15 are pushed bidirectionally towards the ball valve 12, forming an initial metal-to-metal hard contact seal. The total preload of the springs... Initial sealing pressure must be met. The calculation formula can be simplified to meet the requirements as follows: ; in, For the number of springs, The stiffness of a single spring (N / mm). The initial compression of the spring is (mm). The average diameter of the sealing surface (mm). Width of the sealing surface (mm) The required initial sealing pressure (MPa). For example, to achieve a seal at a pressure of 35 MPa, It is typically designed to operate in the range of 40-60 MPa.

[0030] Pressure Adaptive: When high-pressure drilling fluid (e.g., 35MPa or 70MPa) is introduced into the valve, the fluid pressure P acts on the back of the upper valve seat 14 and the lower valve seat 15, generating an additional axial thrust. , ( (This refers to the effective pressure-bearing area of ​​the valve seat). This thrust and spring force The valves move in the same direction, pressing the valve seat more tightly against the ball valve 12 to achieve an adaptive effect of "the higher the pressure, the tighter the seal." At the same time, the floating fit structure between the valve seat and the inner wall of the valve body allows for slight axial displacement to compensate for manufacturing errors, thermal expansion, or wear of the ball valve 12, thus maintaining a reliable seal at all times.

[0031] Real-time monitoring of valve seat wear and floating status: Monitoring baseline establishment: The status indicator ring 23, fixed to the outer wall of the valve seat, floats axially synchronously with the valve seat. A non-contact linear displacement sensor within the external measurement module 3 measures the gap between the sensor and the status indicator ring 23 in real time. .

[0032] Status determination: The system presets a reference gap. (Corresponding to the initial position of the new valve seat) and warning threshold For example, 0.5 to 1.0 mm. The monitoring logic is as follows: Real-time displacement: .

[0033] Wear and tear determination: If Continue to increase and exceed If so, it is determined that wear has occurred on the sealing surfaces of the upper valve seat 14 and the lower valve seat 15. Wear amount .

[0034] Trend Analysis: Through analysis rate of change over time This can predict the remaining life of the valve seat. For example, under constant operating conditions, a sudden increase in the rate of change may indicate a deterioration in operating conditions or abnormal damage to the sealing surface.

[0035] Data transmission: Sensor signals are transmitted via cables to an external signal processing unit for display, alarm, and data recording.

[0036] Intelligent recognition of ball valve position status (12): To achieve accurate identification of the ball valve (12) position, multiple blocking blocks (24) are set at 90-degree intervals or specific angles on the circumferential trajectory corresponding to the ball valve (12) surface and the concealed groove (26). Each blocking block (24) contains a magnetic block (25) with different magnetic strengths. For example, the magnetic block corresponding to the "fully open" position has the strongest magnetic force, the magnetic block corresponding to the "fully closed" position has the weakest magnetic force, and the magnetic block corresponding to the "45-degree open" position has a moderate magnetic force. Since the magnetic blocks (25) and the magnetic ball (28) repel each other, and the repulsive force generated by the magnetic blocks (25) with different magnetic forces on the magnetic ball (28) is different, the magnetic ball (28) is stabilized in a unique equilibrium position in the concealed groove (26) under the combined action of the ball spring (27) and the repulsive force of the magnetic blocks (25), resulting in a unique displacement ΔS. Through finite element simulation or experimental calibration, a one-to-one correspondence table or function curve of "displacement ΔS-ball valve rotation angle" can be established in advance. The dedicated linear displacement sensor in the external measurement module (3) monitors the displacement ΔS of the magnetic ball (28) in real time and transmits the data to the AI ​​data analysis module of the external signal processing unit. The AI ​​module is not a complex deep learning model, but adopts a pattern recognition method based on lookup table or interpolation algorithm: by comparing the real-time measured ΔS value with the pre-stored calibration data table, the current state of the ball valve (12) can be quickly and uniquely identified (such as fully open, fully closed, half open, etc.), and is intuitively indicated by the different colored indicator lights (31) on the housing of the external measurement module (3) (for example, green light represents fully open, red light represents fully closed, and yellow light represents half open).

[0037] Real-time online monitoring and predictive maintenance of valve seat status: Valve seat wear in traditional plug valves is a "hidden fault," requiring periodic disassembly and inspection. This invention directly monitors valve seat movement using non-contact sensors, quantifying wear levels in real time and analyzing trends. This represents a leap from "periodic maintenance" to "predictive maintenance," significantly reducing downhole safety accidents caused by valve seat failure.

[0038] Significantly improves valve sealing reliability and lifespan under harsh operating conditions: The floating seat structure and spring-pressure dual-loading design enable the sealing pair to adaptively compensate for wear, temperature, and pressure changes. Combined with real-time monitoring of wear conditions, intervention can be initiated before sealing performance approaches failure, thereby maximizing the utilization of seat material and extending the overall valve service life.

[0039] Enhance operational safety and status visibility: By using magnetic coding principle to identify the position of ball valve 12 without contact, the problem of traditional mechanical indicators being prone to failure under mud pollution is solved, making the status indication more reliable and intuitive.

[0040] The valve seat wear warning function allows operators to plan replacement operations in advance, avoiding sudden leaks during critical drilling stages (such as high-pressure circulation and controlled pressure drilling), and greatly improving operational safety.

[0041] The non-contact linear displacement sensor is preferably an eddy current displacement sensor or a laser triangulation displacement sensor. Taking the eddy current sensor as an example, its probe end face is opposite to the high magnetic status indicator ring (23). When the status indicator ring (23) moves axially with the valve seat, the gap between the sensor and the indicator ring changes, which causes the impedance and quality factor of the sensor coil to change. By measuring this change, a voltage or current signal proportional to the displacement can be accurately and linearly output, thereby realizing non-contact high-precision displacement measurement.

[0042] The embodiments of the present invention have been described above, but the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms based on the guidance of the present embodiments, all of which are within the protection scope of the present embodiments.

Claims

1. A square drill pipe plug valve with a floating seat for oilfield development, characterized in that, include: A plug valve body (11) is provided with a ball valve (12) rotatably disposed at the center of the plug valve body (11). An upper valve seat (14) and a lower valve seat (15) are respectively disposed on both sides of the ball valve (12). The upper valve seat (14) and the lower valve seat (15) form an axial floating fit structure with the inner wall of the plug valve body (11). The outer wall of the upper valve seat (14) and the outer wall of the lower valve seat (15) are both fixedly provided with status indicator rings (23), and the two status indicator rings (23) float synchronously along with their respective upper valve seat (14) and lower valve seat (15); An external measuring module (3) is fixedly installed on the outer wall of the plug valve body (11). Multiple non-contact linear displacement sensors are integrated in the external measuring module (3). Each linear displacement sensor forms a radially opposed monitoring cooperation with the corresponding status indicator ring (23). Both the upper valve seat (14) and the lower valve seat (15) have spring holes (17) arranged on the side away from the ball valve (12). A push spring (18) is fixedly installed in the spring hole (17). The push spring (18) on the side of the lower valve seat (15) directly pushes against the side wall inside the plug valve body (11), and always pushes the lower valve seat (15) to apply a thrust towards the ball valve (12). A retaining ring (21) is provided on the side of the upper valve seat (14) near the thrust spring (18). All the thrust springs (18) on the side of the upper valve seat (14) are pushed against the retaining ring (21), and a pushing force is always applied to the upper valve seat (14) in the direction of the ball valve (12). The upper valve seat (14) and lower valve seat (15) are provided with a concealed groove (26) inside the sealing surface of the ball valve (12). A magnetic ball (28) is slidably arranged inside the concealed groove (26), and a push ball spring (27) is provided on one side of the magnetic ball (28). The push ball spring (27) always pushes the magnetic ball (28) to move towards the ball valve (12). The ball valve (12) has a block (24) arrayed on the surface corresponding to the position of the concealed groove (26). The block (24) has a magnetic block (25) inside. The magnetic block (25) and the magnetic ball (28) repel each other. The magnetic forces of the several magnetic blocks (25) are different. When the ball valve (12) rotates to different positions, the magnetic blocks (25) with different magnetic forces push the magnetic ball (28) to a different displacement. One of the multiple linear displacement sensors of the external measurement module (3) corresponds to the position of the magnetic ball (28), detects the displacement amplitude of the magnetic ball (28), and determines the state of the ball valve (12) through AI data analysis. The outer wall of the housing of the external measurement module (3) is provided with multiple indicator lights (31), and the lights illuminate differently depending on the state of the ball valve (12). The external measurement module (3) collects the axial displacement of the status indicator ring (23) in real time through the linear displacement sensor, and determines the wear state and axial floating trend of the upper valve seat (14) and lower valve seat (15) based on the preset displacement threshold.

2. The square drill pipe plug valve with a floating seat for oilfield development according to claim 1, characterized in that, The upper valve seat (14) and the lower valve seat (15) each have a locking groove (22) and two annular grooves (16) on their outer walls. The status indicator ring (23) is fixed in the locking groove (22). Each of the two annular grooves (16) is provided with a sealing element (29) for sealing the upper valve seat (14) and the lower valve seat (15) with the inner wall of the plug valve body (11).

3. A square drill pipe plug valve with a floating seat for oilfield development according to claim 2, characterized in that, The status indicator ring (23) is a high-magnetic permalloy ring. The status indicator ring (23) floats together with the valve seat. The sensor signal line of the external measurement module (3) is led out through the connector line and connected to the external signal processing unit.

4. A square drill pipe plug valve with a floating seat for oilfield development according to claim 3, characterized in that, Both the upper valve seat (14) and the lower valve seat (15) are supported by multiple thrust springs (18) to make bidirectional hard contact sealing between the ball valve (12) and the sealing surfaces of the upper valve seat (14) and the lower valve seat (15), ensuring reliable initial sealing and sealing under pressure. The ball valve (12) is plated with hard chrome.

5. A square drill pipe plug valve with a floating valve seat for oilfield development according to claim 4, characterized in that, A knob (13) for controlling the rotation of the ball valve (12) is provided at the center of the outer wall of the plug valve body (11).

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