Well cementation cement head

Abstract

The utility model belongs to the field of petroleum and natural gas well cementation tools, particularly relates to a well cementation cement head, and aims to solve the problems that in the prior art, as a stop pin cannot completely block an internal channel of the cement head, pressure fluctuation in the liquid injection process can drive a rubber plug to move up and down, the placing direction of the rubber plug is deviated seriously, and the cement head cannot be used for well cementation. The rotary valve comprises a body and a rotary valve assembly, a channel and a side channel are formed in the body, the rotary valve assembly is coaxially installed in the body, a bypass is formed in the rotary valve assembly and communicated with the side channel, and a storage space capable of containing the rubber plug is formed in the body. The rubber plug is arranged on the side close to the rotary valve assembly, a platform is arranged on the face, attached to the rubber plug, of the rotary valve assembly, the well cementation valve set can be opened according to the well cementation process, different fluid media flow through the well cementation valve set, cementing and replacement do not interfere with each other, and the rubber plug can be stably released.

Description

Technical Field

[0001] The utility model belongs to the field of petroleum and natural gas cementing tools, and particularly relates to a cementing head. Background Art

[0002] When drilling an oil and gas well, casing is typically installed in an open wellbore to provide stability to the formation walls and isolate and seal off the formation fluid zones. The casing is then cemented to the wellbore walls. More specifically, a casing string is inserted into a wellbore filled with drilling mud. Once the casing string is positioned in the wellbore, a cement head is attached to the top of the casing string. The cement head is a valve system used to inject and remove fluid during cementing. It contains chambers that hold at least two rubber plugs. During cementing, the first rubber plug, often called the "bottom plug," is released into the casing string. Cement slurry is pumped down the casing string until it is positioned at the desired location within the string, typically near the end. As the bottom plug moves downward into the casing string, it wipes away any residual mud from the casing string. Furthermore, the bottom plug isolates the mud in the wellbore below it from the cement slurry in the casing string above it. Once the required amount of cement slurry has been pumped into the casing string, a second plug, commonly known as the "top plug," is released at the top of the cement slurry column, acting as a barrier at the top of the cement slurry column. Various types of displacement fluids can be used to apply pressure to the top plug, pushing it into the casing string. This forces the cement slurry into the annulus formed between the casing string and the wellbore wall through ports formed in the casing or through ports below the bottom plug. As the cement slurry is forced into the annulus, the formation fluids and mud contained in the annulus are forced out of the wellbore and recovered at the top of the casing string, completing the cementing operation.

[0003] Conventional cement heads, because the retaining pins cannot completely seal the internal channels of the cement head, pressure fluctuations during the injection process can cause the plug to move up and down. In severe cases, this can cause the plug to shift in its placement, preventing it from being released. The upward and downward movement of the plug and the suction of liquid can easily cause the retaining pin to bend, rendering it immobile. The valve groups in cement heads are often welded together, and frequent use in high-pressure environments can easily lead to weld failure. Ordinary rubber plugs have short, thin lip edges, large inclination angles, and weak structures. These are prone to wear and tear during long-distance operation in deep wells, or to disc flipping in high-pressure environments, affecting displacement effectiveness and impact pressure. Utility Model Content

[0004] In order to solve the problem in the prior art that, because the stop pin cannot completely block the internal channel of the cement head, the pressure fluctuation during the injection process will cause the rubber plug to move up and down, and in severe cases, the placement direction of the rubber plug will be offset, resulting in the rubber plug being unable to be released, the utility model provides a cementing head, comprising:

[0005] The body has a channel formed in the center along the axis direction, and a side channel formed on one side of the body;

[0006] a rotary valve assembly coaxially mounted in the body, wherein a bypass is provided in the rotary valve assembly and communicates with the side channel;

[0007] A storage space capable of accommodating a rubber plug is formed in the body, and the storage space is sealed by a rotary valve assembly. The rubber plug is arranged on a side close to the rotary valve assembly, and a platform is provided on a side of the rotary valve assembly that is in contact with the rubber plug.

[0008] According to some embodiments of the present application, a cementing head is provided, wherein the rotary valve assembly includes at least a first rotary valve and a second rotary valve, the first rotary valve and the second rotary valve are spaced apart, a first bypass is opened inside the first rotary valve, and a second bypass is opened inside the second rotary valve, the first bypass and the second bypass are both connected to the side channel, and the side channel is selectively connected to the channel through the bypass.

[0009] According to some embodiments of the present application, a cementing head is provided, wherein the rubber plug includes at least a first rubber plug and a second rubber plug, wherein the first rubber plug is arranged on a side close to the first rotary valve, and the second rubber plug is arranged on a side close to the second rotary valve.

[0010] According to some embodiments of the present application, a cementing head is provided, wherein the first rotary valve is provided with a first through hole, through which the first rubber plug and the second rubber plug can pass, and the second rotary valve is provided with a second through hole, through which the second rubber plug can pass.

[0011] According to some embodiments of the present application, a cementing cement head is provided, which also includes a cementing valve group, which includes at least a first cementing valve group, a second cementing valve group and a third cementing valve group. The first cementing valve group and the second cementing valve group are respectively connected to the side channels on both sides of the second rotary valve, and the third cementing valve group is connected to the channel.

[0012] According to some embodiments of the present application, a cementing head is provided, which also includes an indicator and a controller. The indicator and the controller are arranged on both sides of the rotary valve assembly. The controller can receive instructions from the remote control end according to the cementing process and control the rotation of the rotary valve assembly. The indicator can display the rotation angle of the rotary valve assembly and transmit the indication result to the remote control end in real time.

[0013] According to some embodiments of the present application, a cementing head is provided, further comprising a metal seal disposed between the rotary valve assembly and the body.

[0014] According to some embodiments of the present application, a cementing head is provided, further comprising a top cover, which is detachably sealed to the body.

[0015] Beneficial effects of the utility model:

[0016] The internal channel of the main body is equipped with a sealed storage space for placing the plug. The storage space is separated by a rotary valve assembly. The cementing valve group can be opened and circulate different fluid media according to the cementing process. The pressure-balanced structure ensures that only one channel is opened for circulation during the same construction procedure. Cementing and displacement do not interfere with each other and the plug can be released stably.

[0017] It adopts a weld-free, integral high-pressure-bearing structure, and the components are connected with high-strength rectangular quick-release joints. The pressure-balanced structure is designed to ensure that cementing and displacement do not interfere with each other, improve the pressure-bearing capacity of the cement head, and ensure the safety of the plug and the stop pin. By optimizing the angle and structure of the rubber disc and selecting high-wear-resistant materials, the overall tear resistance and wear resistance of the cementing plug are increased, solving the problems of temperature resistance, pressure bearing, and wear resistance of the plug. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Other features, objects and advantages of the present application will become more apparent upon reading the detailed description of non-limiting embodiments made with reference to the following drawings:

[0019] Figure 1 is a schematic diagram of the internal structure of some embodiments of the present application;

[0020] Figure 2 This is a schematic diagram of the specific positions of the first rotary valve and the second rotary valve in some embodiments of the present application.

[0021] In the figure: 10, body; 11, rotary valve assembly; 111, first rotary valve; 112, second rotary valve; 12, indicator; 13, top cover; 14, channel; 15, bypass; 151, first bypass; 152, second bypass; 16, controller; 17, side channel; 18, through hole; 181, first through hole; 182, second through hole; 19, quick connector; 20, rubber plug; 201, first rubber plug; 202, second rubber plug; 21, metal seal; 301, first cementing valve group; 302, second cementing valve group; 303, third cementing valve group. DETAILED DESCRIPTION

[0022] The present application will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are intended only to illustrate the relevant utility model and are not intended to limit the utility model. It should also be noted that, for ease of description, only portions relevant to the relevant utility model are shown in the accompanying drawings.

[0023] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in this application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0024] like Figure 1-2 As shown, the utility model provides a cementing head, a cementing head comprising a body 10 and a rotary valve assembly 11;

[0025] A channel 14 is defined in the center of the body 10 along the axial direction. A side channel 17 is defined on one side of the body 10. The rotary valve assembly 11 is coaxially mounted within the body 10. A bypass 15 is defined within the rotary valve assembly 11. The bypass 15 communicates with the side channel 17. The side channel 17 selectively communicates with the channel 14 via the bypass 15.

[0026] A storage space capable of accommodating the plug 20 is formed in the body 10 , and the storage space is sealed by the rotary valve assembly 11 . The plug 20 is arranged on a side close to the rotary valve assembly 11 , and the rotary valve assembly 11 is provided with a platform on a side in contact with the plug 20 .

[0027] During specific implementation, the main body 10 adopts an integral structural design, is processed as a whole, has no welding points, and has high strength. The main body 10 is a tubular structure, and a channel 14 running through the upper and lower parts is opened in the center. A plug 20 is arranged inside the channel 14, and the channel 14 is divided by a rotary valve assembly 11 to form a storage space for the plug 20. A side channel 17 is also opened along the axial direction on the side, and a bypass 15 is opened in the rotary valve assembly 11. The bypass 15 can control the on and off of the side channel 17. The rotary valve assembly 11 is provided with a platform on the side that is in contact with the plug 20, so that the plug will not be skewed in the channel due to vibration, and the cementing plug 20 is released within a specified time range according to the cementing process.

[0028] In some embodiments, the rotary valve assembly 11 includes at least a first rotary valve 111 and a second rotary valve 112. The first rotary valve 111 and the second rotary valve 112 are spaced apart from each other. A first bypass 151 is provided inside the first rotary valve 111, and a second bypass 152 is provided inside the second rotary valve 112. Both the first bypass 151 and the second bypass 152 are connected to the side channel 17.

[0029] In a specific implementation, the first rotary valve 111 is a lower rotary valve, and the second rotary valve 112 is an upper rotary valve. Correspondingly, the first bypass 151 is located at the lower position of the side channel 17, and the second bypass 152 is located above the first bypass 151 with a gap therebetween.

[0030] The rubber plug 20 at least includes a first rubber plug 201 and a second rubber plug 202 . The first rubber plug 201 is disposed on a side close to the first rotary valve 111 , and the second rubber plug 202 is disposed on a side close to the second rotary valve 112 .

[0031] During specific implementation, the rotary valve assembly 11 is provided with a platform on the side in contact with the plug 20, which can make the plug 20 be placed more stably and prevent it from being vibrated and causing the plug to become skewed in the channel. The cementing plug 20 is released within a specified time range according to the cementing process. The first plug 201 is located in the lower storage space, and the second plug 202 is located in the upper storage space.

[0032] In some embodiments, the first rotary valve 111 is provided with a first through hole 181 through which the first rubber plug 201 and the second rubber plug 202 pass. The second rotary valve 112 is provided with a second through hole 182 through which the second rubber plug 202 passes.

[0033] In a specific implementation, the rotary valve assembly 11 is designed with a through hole 18 , which can rotate 90° and allow the rubber plug 20 to fall from the through hole 18 . The through hole 18 includes a first through hole 181 and a second through hole 182 .

[0034] In some embodiments, a cementing valve group is also included, which includes at least a first cementing valve group 301, a second cementing valve group 302 and a third cementing valve group 303. The first cementing valve group 301 and the second cementing valve group 302 are respectively connected to the side channels 17 on both sides of the second rotary valve 112, and the third cementing valve group 303 is connected to the channel 14.

[0035] During specific implementation, at least one pipe with a valve in the cementing valve group is connected to the channel 14, and the other two pipes with valves are connected to the side channel 17. The cementing valve group can be opened and circulate different fluid media according to the cementing process. The cementing valve group adopts a pressure-balanced structure, which can ensure that only one of the channels is opened for circulation in the same construction procedure, and cementing and displacement do not interfere with each other; the cement head can be connected to the casing through a quick-release thread.

[0036] In some embodiments, an indicator 12 and a controller 16 are also included. The indicator 12 and the controller 16 are arranged on both sides of the rotary valve assembly 11. The controller 16 can receive instructions from the remote control end and control the rotation of the rotary valve assembly 11 according to the cementing process. The indicator 12 can display the rotation angle of the rotary valve assembly 11 and transmit the indication result to the remote control end in real time.

[0037] During specific implementation, the controller 16 and the indicator 12 are set corresponding to the rotary valve assembly 11. The controller 16 can receive instructions from the remote control end to control the rotation of the rotary valve assembly 11 according to the cementing process. The indicator 12 can display the rotation angle of the rotary valve assembly 11 and transmit the indication result to the remote control end in real time.

[0038] During specific implementation, after the cement head is connected to the casing through the quick-release thread, the first cementing valve group 301 channel is opened, and the drilling fluid pre-fluid passes through the side channel 17 and the first bypass 151 of the first rotary valve 111 and enters the channel 14. At this time, the space between the first rotary valve 111 and the second rotary valve 112 of the cement head and between the second rotary valve 112 and the top cover 13 are all sealed storage spaces, and no fluid enters them. According to the next cementing process, the first rotary valve 111 rotates 90°, and the rotary valve indicator 12 transmits the open position signal to the remote control end, and the first rubber plug 201 falls through the first through hole 181. At this time, the second rotary valve 111 and the second rotary valve 112 are sealed storage spaces. The first bypass 151 is blocked, and the second cementing valve group 302 channel is opened. The cementing cement slurry is connected to the channel 14 through the side channel 17, the second bypass 152, and the first through hole 181, and the first plug 201 is pressed into the well. Continuing the next cementing process, the second rotary valve 112 is rotated 90 degrees, and the rotary valve indicator 12 transmits the open position signal to the remote control end. The second plug 202 falls through the second through hole 182 and the first through hole 181, and the second bypass 152 is blocked. The third cementing valve group 303 channel is opened, and the plugging fluid passes through the channel 14 and enters the well along with the second plug 202, completing the cementing operation.

[0039] In some embodiments, a metal seal 21 is further included, and the metal seal 21 is disposed between the rotary valve assembly 11 and the body 10 .

[0040] In specific implementation, a special-shaped metal seal 21 is used between the rotary valve assembly 11 and the body 10 to achieve sealing, thereby improving the pressure-bearing strength and having a higher pressure-bearing capacity.

[0041] In some embodiments, a top cover 13 is further included, and the top cover 13 is detachably sealed to the body 10 .

[0042] In a specific implementation, when the top cover 13 is opened, the rubber plug can be removed through the upper top cover 13 and then installed. When the top cover 13 is closed, the top of the channel 14 can be sealed from the outside.

[0043] In the description of this utility model, terms such as "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer" indicating directions or positional relationships are based on the directions or positional relationships shown in the accompanying drawings. These are merely for ease of description and are not intended to indicate or imply that the device or component described must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0044] Furthermore, it should be noted that, in the description of this utility model, unless otherwise expressly specified or limited, the terms "installed," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections, electrical connections; direct connections, indirect connections through an intermediate medium, and internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this utility model based on specific circumstances.

[0045] The term "comprise" or any other similar term is intended to cover non-exclusive inclusion such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed or inherent to such process, method, article, or apparatus.

[0046] Thus far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to these specific embodiments. Without departing from the principles of the present invention, those skilled in the art may make equivalent changes or substitutions to the relevant technical features, and the technical solutions after such changes or substitutions will fall within the scope of protection of the present invention.

Claims

1. A cementing head, characterized in that: include: The main body (10) has a channel (14) opened in the center along the axial direction, and a side channel (17) opened on one side of the interior of the main body (10); A rotary valve assembly (11) is coaxially mounted in the body (10), wherein a bypass (15) is provided in the rotary valve assembly (11), and the bypass (15) is communicated with the side channel (17); A storage space capable of accommodating a rubber plug (20) is formed in the body (10), and the storage space is sealed by a rotary valve assembly (11). The rubber plug (20) is arranged on a side close to the rotary valve assembly (11), and the rotary valve assembly (11) is provided with a platform on a side in contact with the rubber plug (20).

2. A cementing head according to claim 1, characterized in that: The rotary valve assembly (11) comprises at least a first rotary valve (111) and a second rotary valve (112). The first rotary valve (111) and the second rotary valve (112) are spaced apart from each other. A first bypass (151) is provided inside the first rotary valve (111), and a second bypass (152) is provided inside the second rotary valve (112). Both the first bypass (151) and the second bypass (152) are connected to the side channel (17). The side channel (17) is selectively connected to the channel (14) through the bypass (15).

3. A cementing head according to claim 2, characterized in that: The rubber plug (20) comprises at least a first rubber plug (201) and a second rubber plug (202), wherein the first rubber plug (201) is arranged on a side close to the first rotary valve (111), and the second rubber plug (202) is arranged on a side close to the second rotary valve (112).

4. A cementing head according to claim 3, characterized in that: The first rotary valve (111) is provided with a first through hole (181) capable of allowing the first rubber plug (201) to pass through, and the second rotary valve (112) is provided with a second through hole (182) capable of allowing the second rubber plug (202) to pass through.

5. The cementing head according to claim 3, characterized in that: The invention also includes a cementing valve group, which includes at least a first cementing valve group (301), a second cementing valve group (302) and a third cementing valve group (303). The first cementing valve group (301) and the second cementing valve group (302) are respectively connected to the side channels (17) on both sides of the second rotary valve (112), and the third cementing valve group (303) is connected to the channel (14).

6. The cementing head according to claim 1, characterized in that: The invention also includes an indicator (12) and a controller (16), wherein the indicator (12) and the controller (16) are arranged on both sides of the rotary valve assembly (11); the controller (16) can receive instructions from a remote control end according to a cementing process and control the rotation of the rotary valve assembly (11); the indicator (12) can display the rotation angle of the rotary valve assembly (11) and transmit the indication result to the remote control end in real time.

7. The cementing head according to claim 1, characterized in that: It also includes a metal seal (21), which is arranged between the rotary valve assembly (11) and the body (10).

8. The cementing head according to claim 1, characterized in that: It also includes a top cover (13), which is detachably sealed to the body (10).

Images