A top drive plug valve

Abstract

The present application relates to a top drive plug valve, relates to the field of oil and gas drilling and well control equipment, the cone barrel is coaxially arranged in the valve body, and is arranged close to the feed end of the valve body, the valve core is arranged close to the discharge end of the valve body, the cone barrel and the side wall of the valve body form an annular cavity, the cavity has an inlet close to the feed end of the valve body and an outlet close to the discharge end of the valve body, the inlet and the outlet are respectively provided with a feed one-way assembly and a discharge one-way assembly, the feed one-way assembly and the discharge one-way assembly enable the fluid to flow unidirectionally from the inlet to the outlet of the cavity, and the inner diameter of the cone barrel gradually decreases in the direction from the feed end to the discharge end of the valve body. The beneficial effects of the present application are: the structure design is reasonable, the structural parts are few, the stability is high, the application range is wide, the service life is long, and the opening and closing torque of the top drive plug valve under unbalanced pressure can be effectively reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of oil and gas drilling and well control equipment, in particular to a top drive plug valve. BACKGROUND

[0002] The top drive plug valve is connected between the top drive spindle and the protection joint, and is a control valve for opening and closing the internal passage of the drill string in the drill string circulation system. The function of the top drive plug valve is to block the internal passage of the drill string when the formation pressure exceeds the static column pressure of the mud during drilling, so that the mud is not pushed upward along the drill string and well kick and blowout accidents are avoided.

[0003] The top drive plug valve is divided into a top drive upper plug valve and a top drive lower plug valve, both of which have basically the same structure and are ball valve structure kelly valves. The top drive upper plug valve is driven by a hydraulic actuator and is operated and closed by the driller through the top drive control box. The top drive lower plug valve is a manual drill string safety valve and is manually driven by a wrench to open and close. When special conditions occur, such as hydraulic equipment or control console failure, the top drive upper plug valve cannot be opened and closed by the hydraulic actuator, and the opening and closing torque of the plug valve is the key to determining whether the lower plug valve can be manually opened and closed. Since there is a certain safety risk in manually closing the valve, the closing torque needs to be evaluated before closing.

[0004] According to research, an ordinary adult can normally output a torque of 600 N·m using a common wrench. When overflow occurs, the internal passage area of the drill pipe decreases during the process of closing the plug valve ball valve, the pressure difference between the valve core increases, and the friction torque increases, which can easily lead to rotation failure and failure to close. Therefore, a top drive plug valve that can reduce the torque needs to be developed.

[0005] Most domestic research on the top drive plug valve focuses on the mechanism analysis of the failure mode of the top drive plug valve and the structural improvement measures, and there is little research and analysis on the specific value of the opening and closing torque under unbalanced pressure conditions. Foreign research focuses on the improvement of the structure of the top drive plug valve and the research and improvement of the driving device of the top drive plug valve. For example, the driving device of the Canadian Hi-Kalibre company realizes the opening and closing of the top drive upper plug valve through a gear and rack mechanism. The driving device of the American NOV company drives the sliding sleeve to move up and down through a hydraulic cylinder and connecting rod, and at the same time drives the rocker assembly built in the sliding sleeve to rotate to realize the opening and closing of the top drive plug valve. Some manufacturers have also researched how to reduce the friction between the valve core and the valve seat. For example, Griffith added trunnions on both sides of the ball valve, and metal rolling radial bearings were installed on the trunnions to support and reduce the friction torque. Kelleyguard adopted an automatic pressure balance channel to reduce the friction torque between the valve core and the valve seat and to reduce the opening torque.

[0006] At present, the structure of the top drive plug valve used in the field is basically the same, and the reduction of the opening and closing torque of the ball valve generally starts from the surface treatment of the ball valve to reduce the friction coefficient of the surface of the ball valve, thereby reducing the opening and closing torque. When overflow occurs, the plug valve with the surface treatment process to reduce the surface roughness of the ball valve will not change the pressure on the valve core and the valve seat, and the reduced opening and closing torque value is limited.

[0007] According to research, the pressure of the fluid in the plug valve is an important factor affecting the torque required for opening and closing, the greater the internal fluid pressure, the greater the pressure on the valve core, the greater the friction between the valve core and the ball seat, and the greater the torque required for opening and closing, therefore, reducing the pressure of the fluid in the plug valve is the key to reducing the closing torque. The present application aims at this problem and proposes a top drive plug valve which reduces the pressure on the valve core by increasing the loss when the internal fluid is large, thereby reducing the torque required for closing the valve. SUMMARY

[0008] The technical problem to be solved by the present application is how to reduce the torque required for closing the valve core of the top drive plug valve.

[0009] The technical solution of the present application to solve the above technical problem is as follows: a top drive plug valve, comprising a valve body and a valve core arranged in the valve body, further comprising a conical cylinder, the conical cylinder is coaxially arranged in the valve body and is arranged close to the inlet end of the valve body, the valve core is arranged close to the outlet end of the valve body, the conical cylinder and the side wall of the valve body form an annular cavity, the cavity has an inlet close to the inlet end of the valve body and an outlet close to the outlet end of the valve body, the inlet and the outlet are respectively provided with an inlet one-way assembly and an outlet one-way assembly, the inlet one-way assembly and the outlet one-way assembly allow the fluid to flow from the inlet to the outlet of the cavity in one direction, the inner diameter of the conical cylinder gradually decreases from the inlet end to the outlet end of the valve body.

[0010] The beneficial effect of the present application is that when the well bottom pressure increases sharply due to well kick, blowout and other accidents, the feeding one-way assembly is pushed open by the pressure, part of the fluid flows into the cavity, and then pushes open the discharging one-way assembly, flows out of the cavity, and collides with another part of the normal fluid in the valve body, thereby generating internal fluid vortex and collision, reducing the fluid pressure in the top drive plug valve, reducing the pressure between the valve core and the valve body, and further reducing the friction when the valve core rotates, and reducing the torque required when closing the valve. The structure is relatively simple to process and can be widely used in the field of oil and gas drilling. Especially for the situation that the downhole working condition is complex, the well site environment is poor, and the top drive plug valve is under unbalanced pressure. In addition, the reduction of the pressure between the valve core and the upper valve seat can reduce the damage degree of the ball valve structure and prolong its service life. Compared with the prior art, the present application has reasonable structure design, fewer structural parts, high stability, wide application range, long service life, and can effectively reduce the opening and closing torque of the top drive plug valve under unbalanced pressure.

[0011] The inner wall of the conical cylinder is conical. According to Bernoulli's principle, the flow area of the outlet with a smaller diameter is small, the flow speed is fast, and the pressure is small. The flow area of the inlet with a larger diameter is large, the flow speed is slow, and the pressure is large. Therefore, the pressure at the inlet is greater than that at the outlet, which can ensure that there is a pressure difference between the inlet and the outlet of the cavity, so that the fluid can smoothly enter the inside of the cavity.

[0012] On the basis of the above technical scheme, the present application can be further improved as follows.

[0013] Further, the inlet and the outlet are both arranged on the conical cylinder.

[0014] Further, the outer diameter of the conical cylinder gradually decreases from the feeding end to the discharging end of the valve body.

[0015] The beneficial effect of the further scheme is that the side wall of the conical cylinder towards the inside of the cavity is conical, so that the outlet of the cavity is inclined, and the fluid flowing out of the cavity collides with the original fluid in the valve body at a certain angle, and the fluid pressure is reduced significantly.

[0016] Further, the feeding one-way assembly comprises a compression spring and a sliding plug, one end of the compression spring is fixedly connected with the valve body, the other end is fixedly connected with the sliding plug, and the sliding plug is slidingly arranged in the inlet.

[0017] Further, the sliding plug is provided with first one-way teeth, the cavity is provided with second one-way teeth, the first one-way teeth and the second one-way teeth are engaged, and the sliding plug can move one-way into the cavity.

[0018] The beneficial effect of the further scheme is that the sliding plug can only be opened in one direction and cannot be reset under the change of fluid pressure itself.

[0019] Further, the discharging one-way component is a one-way valve.

[0020] The beneficial effect of the further scheme is that the one-way valve structure of the finished product is more stable and convenient to install.

[0021] Further, the top drive plug valve further comprises an upper ball seat fixed in the valve body, and the valve core is rotatably installed in the upper ball seat.

[0022] The beneficial effect of the further scheme is that the upper ball seat is used to limit the position of the valve core, so that the valve core assembly is reliable.

[0023] Further, the top drive plug valve further comprises a split stop ring fixedly connected with the inner wall of the valve body and abutting against one end of the upper ball seat in the axial direction.

[0024] The beneficial effect of the further scheme is that the split stop ring is used to limit the axial position of the upper ball seat, facilitating the installation of the upper ball seat.

[0025] Further, the top drive plug valve further comprises a handle fixedly connected with the valve core at one end and extending out of the side wall of the valve body at the other end.

[0026] The beneficial effect of the further scheme is that the other end of the handle is used to connect a matching wrench, and by rotating the wrench, the valve core is rotated at a fixed position, realizing the opening and closing of the valve.

[0027] Further, the inlet end and the outlet end of the valve body are respectively provided with a lower joint and an upper joint.

[0028] The beneficial effect of the further scheme is that the valve body is connected to the pipeline through the lower joint and the upper joint. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 It is a half sectional view of the top drive plug valve of the present application.

[0030] Figure 2 It is a fluid flow direction schematic diagram of the top drive plug valve of the present application.

[0031] Figure 3 It is a left view of the cone cylinder of the present application.

[0032] Figure 4This is a schematic diagram of the mating structure of the first unidirectional tooth and the second unidirectional tooth.

[0033] The attached diagram lists the components represented by each number as follows:

[0034] 1. Upper connector; 2. Matching retaining ring; 3. Upper ball seat; 4. Handle; 5. Valve core; 6. Valve body; 7. Check valve; 8. Cone; 9. Cavity; 10. Compression spring; 11. Sliding plug; 12. Lower connector; 13. Inlet; 14. Outlet. Detailed Implementation

[0035] The principles and features of the present invention are described below. The examples given are only for explaining the present invention and are not intended to limit the scope of the present invention.

[0036] like Figures 1-4 As shown, this embodiment provides a top-drive plug valve, including a valve body 6 and a valve core 5 disposed within the valve body 6, and also includes a cone 8. The cone 8 is coaxially disposed within the valve body 6 and is located near the feed end of the valve body 6. The valve core 5 is located near the discharge end of the valve body 6. The cone 8 and the side wall of the valve body 6 form an annular cavity 9. The cavity 9 has an inlet 13 near the feed end of the valve body 6 and an outlet 14 near the discharge end of the valve body 6. The inlet 13 and the outlet 14 are respectively provided with a one-way feed assembly and a one-way discharge assembly. The one-way feed assembly and the one-way discharge assembly allow fluid to flow unidirectionally from the inlet 13 to the outlet 14 of the cavity 9. The inner diameter of the cone 8 gradually decreases along the direction from the feed end to the discharge end of the valve body 6.

[0037] When an accident such as a well kick or blowout causes a sharp increase in bottom hole pressure, the feed one-way component is forced open by the pressure, allowing some fluid to flow into cavity 9. This then forces open the discharge one-way component, allowing fluid to flow out of cavity 9 and counteract the normal flow of fluid within valve body 6. This creates internal fluid vortexes and counteracting, thereby reducing the fluid pressure inside the top-drive plug valve, decreasing the pressure between valve core 5 and valve body 6, and consequently reducing the frictional force during valve core 5 rotation, thus lowering the torque required to close the valve. This structure is relatively simple to manufacture and can be widely applied in oil and gas drilling. It is particularly suitable for situations where complex downhole conditions and harsh well environments can easily cause the top-drive plug valve to operate under unbalanced pressure conditions. Furthermore, the reduced pressure between the valve core and upper valve seat can lessen the damage to the ball valve structure and extend its service life. Compared with existing technologies, this invention has a reasonable structural design, fewer structural parts, high stability, wide applicability, and long service life, effectively reducing the opening and closing torque of the top-drive plug valve under unbalanced pressure.

[0038] The inner wall of the cone 8 is cone-shaped. According to Bernoulli's principle, the outlet 14, with its smaller diameter, has a smaller flow area, higher flow velocity, and lower pressure, while the inlet 13, with its larger diameter, has a larger flow area, lower flow velocity, and higher pressure. Therefore, the pressure at the inlet 13 is greater than the pressure at the outlet 14, ensuring a pressure difference between the inlet 13 and the outlet 14 of the cavity 9, allowing the fluid to smoothly enter the cavity 9.

[0039] The inner diameter of the cone 8 gradually decreases from the feed end to the discharge end. Optionally, the inner wall of the cone 8 is entirely conical, or the feed end to the middle of the cone 8 is conical, and its discharge end is a cylinder connected to the conical shape.

[0040] Optionally, multiple one-way feed assemblies are provided along the circumference of the cone.

[0041] Optionally, multiple one-way discharge assemblies are provided along the circumference of the cone.

[0042] Based on any of the above schemes, both the inlet 13 and the outlet 14 are located on the cone 8.

[0043] Based on any of the above schemes, the outer diameter of the cone 8 gradually decreases along the direction from the feed end to the discharge end of the valve body 6.

[0044] The outlet 14 is perpendicular to the side wall of the cone 8. The side wall of the cone 8 facing the cavity 9 is conical, so the outlet 14 of the cavity 9 is set at an angle, so that the fluid flowing out of the cavity 9 and the original fluid of the valve body 6 collide at a certain angle, and the fluid pressure is significantly reduced.

[0045] Based on any of the above schemes, the one-way feeding assembly includes a compression spring 10 and a sliding plug 11. One end of the compression spring 10 is fixedly connected to the valve body 6, and the other end is fixedly connected to the sliding plug 11. The sliding plug 11 is slidably disposed in the inlet 13.

[0046] Based on any of the above schemes, such as Figure 4 As shown, the sliding plug 11 is provided with a first one-way tooth, and the cavity 9 is provided with a second one-way tooth. The first one-way tooth and the second one-way tooth mesh, and the sliding plug 11 can move unidirectionally into the cavity 9.

[0047] The sliding plug 11 can only open in one direction and cannot reset under changes in fluid pressure. Because the pressure difference between inlet 13 and outlet 14 is unstable, if a normal resettable check valve is installed at inlet 13, the valve's opening and closing will be unstable, affecting the smooth entry of fluid into cavity 9. However, if the sliding plug 11 is designed to open in only one direction, it ensures smooth fluid entry into the cavity and achieves pressure reduction.

[0048] Specifically, the first one-way tooth comprises a bevel and a straight surface, and the straight surface is perpendicular to the axis of the sliding plug 11. The second one-way tooth is a tooth-shaped structure that is mutually embedded with the first one-way tooth. The bevels of the first one-way tooth and the second one-way tooth abut and can move relative to each other along the bevels; the straight surfaces of the first one-way tooth and the second one-way tooth abut and limit the movement of the sliding plug 11 out of the cavity 9.

[0049] On the basis of any of the above solutions, the discharge one-way assembly is a one-way valve 7.

[0050] The one-way valve 7 of the finished product is more stable in structure and convenient to install.

[0051] On the basis of any of the above solutions, the top drive plug valve further comprises an upper ball seat 3, which is fixed in the valve body 6, and the valve core 5 is rotatably installed in the upper ball seat 3.

[0052] On the basis of any of the above solutions, the upper ball seat 3 is used to limit the position of the valve core 5, so that the valve core 5 is reliably assembled.

[0053] On the basis of any of the above solutions, the top drive plug valve further comprises a split retaining ring 2, which is fixedly connected with the inner wall of the valve body 6 and abuts against one end of the upper ball seat 3 in the axial direction.

[0054] The split retaining ring 2 is used to limit the axial position of the upper ball seat 3, so that the upper ball seat 3 is conveniently installed.

[0055] On the basis of any of the above solutions, the top drive plug valve further comprises a handle 4, one end of which is fixedly connected with the valve core 5, and the other end extends out of the side wall of the valve body 6.

[0056] The other end of the handle 4 is used to connect a matching wrench, and by rotating the wrench, the valve core 5 is rotated at a fixed position, so that the valve is opened and closed.

[0057] On the basis of any of the above solutions, the valve body 6 has a lower joint 12 and an upper joint 1 at the inlet end and the outlet end, respectively.

[0058] The valve body 6 is connected to a pipeline through the lower joint 12 and the upper joint 1.

[0059] In one specific embodiment, the cone 8 separates the cavity 9 from the middle passage of the valve body 6, and the cavity 9 is filled with air. Three one-way valves 7 are arranged in the positions shown in the figure, and are evenly distributed in the circumferential direction on the cone 8. The one-way valves 7 only allow fluid in the cavity 9 to flow to the middle passage, and the opening pressure is very small. Three sets of compression springs 10 and sliding plugs 11 are arranged in the positions shown in the figure, and are evenly distributed in the circumferential direction on the inlet end of the cone. The sliding plugs 11 only allow sliding in the direction of compression of the springs, that is, when the compression springs 10 are further compressed, the sliding plugs 11 slide in the axial compression direction of the springs, and cannot be reset once "opened", so that the middle passage is in communication with the cavity 9.

[0060] Figure 1 For the fully open state of the valve core 5, and the state in which the torque reduction structure (one-way valve 7, cavity 9, compression spring 10 and sliding plug 11) does not work, when the internal fluid pressure of the plug valve is normal and lower than the threshold value at which the compression spring 10 is compressed, the compression spring 10 will not be compressed, and the sliding plug 11 will not slide. The fluid flows directly out of the middle passage, and at this time, neither the compression spring 10 nor the sliding plug 11 changes, so the fluid does not enter the cavity 9.

[0061] Figure 2 For the fully open state of the valve, and the state in which the torque reduction structure has worked, the arrows indicate the flow of fluid. When the internal fluid pressure is higher than the threshold value, the compression spring 10 will be compressed, and the sliding plug 11 will slide in the compression direction in one direction, the middle passage will be in communication with the cavity 9, the fluid in the cavity 9 will flow out of the one-way valve 7, and will collide with the fluid in the middle passage of the valve body 6, thereby reducing the internal fluid pressure of the top drive plug valve, reducing the pressure between the valve core 5 and the upper ball seat 3, and further reducing the friction when the valve core 5 rotates, thereby reducing the torque required to close the valve.

[0062] It should be noted that when a dangerous accident occurs, the pressure in the top drive plug valve will increase sharply, the torque reduction structure will be activated, and the top drive plug valve generally needs to be closed urgently. After the accident is handled, the sliding plug 11 can be restored during equipment maintenance (for example, the sliding plug 11 is removed and reassembled into the inlet 13 from the middle passage).

[0063] The use of the top drive plug valve includes at least the following two working conditions:

[0064] Working condition 1: to reduce the pressure when an abnormal working condition occurs.

[0065] When the abnormal situation such as well kick, blowout and the like occurs, the fluid pressure in the middle passage of the plug valve rises sharply, at this time, the compression spring 10 will be compressed, the fluid will enter the cavity 9 from the sliding plug 11, because the pressure at the sliding plug 11 is greater than the pressure at the one-way valve 7, so the fluid will flow out from the one-way valve 7. The vortex and backflow will be caused at the one-way valve 7 in the middle passage, so that the fluid pressure passing through the valve core 5 part is lower than the fluid pressure at the sliding plug 11, which helps to reduce the torque when closing the valve core 5.

[0066] Working condition 2: pressure reduction is realized during the closing process of the valve.

[0067] During the process of the valve core 5 from fully open to fully closed, rotating the valve core 5 will make the flow area of the middle passage gradually decrease, the internal pressure below the valve gradually increases, and the required torque also gradually increases. When the pressure exceeds a certain value, the compression spring 10 and the sliding plug 11 will be compressed, the communication cavity 9 and the middle passage are connected, which is consistent with the principle in working condition 1. Finally, the internal pressure is reduced, and the torque required for closing the valve is reduced.

[0068] In the description of the present application, it should be noted that the terms "axial", "radial", "circumferential" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0069] In the description of the present application, the meaning of "a plurality of" is at least two, for example, two, three, etc., unless otherwise explicitly and specifically limited.

[0070] In the description of the present application, the description of the terms "one embodiment", "some embodiments", "example", "specific example" or "some examples" and the like means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any appropriate manner in any one or more embodiments or examples. In addition, the person skilled in the art can combine and combine the different embodiments or examples described in the present specification and the features of the different embodiments or examples without contradiction.

[0071] In the description of the application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connecting" should be understood in a broad sense, for example, it can be fixed connection, or detachable connection, or integrally connected; it can be directly connected, or indirectly connected through an intermediate medium, or the internal communication of two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0072] The above only describes the preferred embodiments of the present application, and is not intended to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A top drive plug valve comprising a valve body (6) and a valve plug (5) arranged inside the valve body (6), characterized in that, Further comprising a conical cylinder (8) coaxially arranged in the valve body (6) and arranged close to the feed end of the valve body (6), the valve core (5) is arranged close to the discharge end of the valve body (6), the conical cylinder (8) and the side wall of the valve body (6) form an annular cavity (9), the cavity (9) has an inlet (13) close to the feed end of the valve body (6) and an outlet (14) close to the discharge end of the valve body (6), the inlet (13) and the outlet (14) are respectively provided with a feed one-way assembly and a discharge one-way assembly, the feed one-way assembly and the discharge one-way assembly enable the fluid to flow from the inlet (13) to the outlet (14) of the cavity (9) in one direction, the inner diameter of the conical cylinder (8) gradually decreases along the direction from the feed end to the discharge end of the valve body (6); The inlet (13) and the outlet (14) are arranged on the conical cylinder (8); The outer diameter of the conical cylinder (8) gradually decreases along the direction from the feed end to the discharge end of the valve body (6); The feed one-way assembly comprises a compression spring (10) and a sliding plug (11), one end of the compression spring (10) is fixedly connected with the valve body (6), the other end is fixedly connected with the sliding plug (11), and the sliding plug (11) is slidingly arranged in the inlet (13); The sliding plug (11) is provided with first one-way teeth, the cavity (9) is provided with second one-way teeth, the first one-way teeth and the second one-way teeth are engaged, and the sliding plug (11) can move in one direction into the cavity (9).

2. A top drive plug valve according to claim 1, wherein, The discharge one-way assembly is a one-way valve (7).

3. A top drive plug valve according to claim 1, wherein, Further comprising an upper ball seat (3) fixed in the valve body (6), the valve core (5) is rotatably installed in the upper ball seat (3).

4. A top drive plug valve according to claim 3, wherein, Further comprising a split retaining ring (2) fixedly connected with the inner wall of the valve body (6) and abutting against one end of the upper ball seat (3) in the axial direction.

5. A top drive plug valve according to claim 1, wherein, Further comprising a handle (4) fixedly connected with the valve core (5) at one end and extending out of the side wall of the valve body (6) at the other end.

6. A top drive plug valve according to any one of claims 1 to 5, wherein, The feed end and the discharge end of the valve body (6) are respectively provided with a lower connector (12) and an upper connector (1).

Images