Dual annular channel cement head and method of installing a rubber plug

Abstract

The application discloses a double-ring channel cementing head and a rubber plug mounting method. The double-ring channel cementing head comprises a body, a rubber plug sleeve, a blocking pin device and a tongue plate. The rubber plug sleeve is arranged in the body and is used for arranging a rubber plug. A cavity is formed between the rubber plug sleeve and the body. An outer wall of the rubber plug sleeve is provided with a limiting ring. The blocking pin device can act on the limiting ring to limit the rubber plug sleeve. A lower end of the rubber plug sleeve is provided with a hinging mechanism. A middle part of the tongue plate is hinged to the lower end of the rubber plug sleeve through the hinging mechanism. An inner wall of the body is provided with an abutting part which can make a first end of the tongue plate abut. The double-ring channel cementing head and the rubber plug mounting method avoid the problem that the rubber plug sealing ring is damaged due to the contact between the blocking pin and the rubber plug sleeve display and the cementing rubber plug in the traditional cementing head.

Description

Technical Field

[0001] This invention relates to the field of downhole tools for cementing operations, and in particular to a method for installing a double-annular channel cement head and rubber plug. Background Technology

[0002] As drilling technology develops from shallow and medium-deep wells to deep and ultra-deep wells, the cementing operation environment becomes increasingly complex, the length of the cementing string becomes longer, the working pressure of the cement head gradually increases, the operation difficulty increases accordingly, and the danger to construction personnel during cementing operations also increases.

[0003] Currently, commonly used cement heads all employ a stop pin structure. When opening the stop pin during cementing operations, the following problems can easily occur: the stop pin may not open properly, preventing the rubber plug from descending normally; if the stop pin is not fully open, the rubber plug may descend simultaneously due to pressure differential, damaging the rubber plug's sealing ring; it may be impossible to determine whether the rubber plug has descended normally, or the descending indicator may fail due to the rubber plug opening, making it impossible to accurately judge the rubber plug's descent status; furthermore, traditional cement heads have a uniform inner diameter, making it difficult to install the rubber plug, and the vacuum suction during cementing can easily bend the stop pin or make it difficult to open. Often, due to the cement head structure or erroneous operations caused by the cumbersome traditional process, major cementing accidents can occur.

[0004] Therefore, it is necessary to utilize new cementing heads to fundamentally guarantee cementing quality, improve production efficiency, and ensure the safe operation and construction of wellhead cementing heads. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide a method for installing a double-ring channel cementing head and rubber plug, effectively solving the problems of difficulty in opening the retaining pin, easy damage to the rubber plug sealing ring, inability to correctly judge the downward movement of the rubber plug, and potential safety hazards in existing cementing heads.

[0006] To achieve the above objectives, the technical solution provided by this invention is as follows:

[0007] A double-ring channel cementing head includes a body, a rubber plug sleeve, a stop pin device, and a tongue plate.

[0008] The rubber stopper sleeve is located inside the body and is used to house the rubber stopper. A cavity is formed between the rubber stopper sleeve and the body, and a limit ring is provided on the outer wall of the rubber stopper sleeve.

[0009] The stop pin device can act on the limit ring to limit the rubber plug sleeve;

[0010] The lower end of the rubber stopper sleeve is provided with a hinge mechanism, and the middle part of the tongue plate is hinged to the lower end of the rubber stopper sleeve through the hinge mechanism. The inner wall of the body is provided with an abutment part that allows the first end of the tongue plate to abut.

[0011] Furthermore, it also includes a liquid inlet device, which is mounted on the main body and the outlet of the liquid inlet device is connected to the inside of the rubber stopper sleeve.

[0012] Furthermore, it also includes a rubber stopper sleeve limiting tube, the lower end of which has an inner diameter slightly larger than the outer diameter of the rubber stopper sleeve, so that the upper end of the rubber stopper sleeve can be confined within the rubber stopper sleeve limiting tube.

[0013] The rubber stopper sleeve limiting tube is provided with a first circulation hole, which is connected to the liquid outlet of the liquid inlet device.

[0014] The rubber stopper sleeve is provided with a second circulation hole, and the distance between the second circulation hole and the lower end of the rubber stopper sleeve is greater than the height of the rubber stopper.

[0015] Furthermore, it also includes a rubber stopper display, which is connected to the limiting ring and displays the travel distance of the limiting ring.

[0016] Furthermore, the rubber plug display includes a rubber plug display lever and a rubber plug display pointer. The rubber plug display lever extends into the body and is connected to a limiting ring. The rubber plug display pointer is connected to the rubber plug display lever and is configured to control the position of the rubber plug display pointer through the rubber plug display lever.

[0017] Furthermore, along the direction from the rubber stopper sleeve limiting tube to the rubber stopper sleeve, the outer surface of the limiting ring gradually slopes towards the center of the limiting ring to form a first inclined surface;

[0018] The stop pin device includes a limiting post, an outer stop pin, an inner stop pin, and a stop pin handwheel. The first end of the limiting post passes through the body cylinder wall and enters the body and abuts against the first inclined surface. The second end of the limiting post is connected to the outer stop pin. The outer stop pin is threaded to one end of the inner stop pin. The other end of the inner stop pin is connected to the stop pin handwheel. The limiting post moves closer to or away from the rubber stop sleeve by rotating the stop pin handwheel.

[0019] Furthermore, the liquid inlet device includes a liquid inlet seat and a liquid inlet cylinder. The liquid inlet seat is fixedly installed on the cylinder wall of the main body outside the main body. The liquid inlet cylinder is perpendicular to the cylinder wall of the main body and centrally located in the liquid inlet seat. The liquid inlet cylinder has a liquid outlet.

[0020] Furthermore, it also includes a top cover and a lower connector, the top cover being detachably and fixedly connected to the upper end of the body, and the upper end of the lower connector being fixedly connected to the lower end of the body.

[0021] A method for installing a plug in a double-annular channel cementing head is provided, which is achieved using the aforementioned double-annular channel cementing head.

[0022] Furthermore, the stop pin device limits the rubber plug sleeve to the first position, and the rubber plug is installed inside the rubber plug sleeve. Then, circulating drilling fluid is injected first.

[0023] Then, cement is injected. When the amount of cement injected meets the cementing requirements, the retaining pin device is removed from the rubber plug sleeve. The rubber plug sleeve moves down, pushes open the tongue plate, and the rubber plug is released.

[0024] The beneficial effects of this invention are as follows:

[0025] The present invention relates to a method for installing a dual-annular channel cementing head and rubber plug. This method utilizes the rubber plug sleeve indicator and limiting post to abut against the limiting ring of the rubber plug sleeve, avoiding the problem of damage to the rubber plug sealing ring caused by contact between the stop pin and the rubber plug sleeve indicator and the cementing rubber plug in traditional cementing heads. The dual-annular channel cementing head is achieved through the rubber plug sleeve and the main body. The rubber plug sleeve facilitates the installation and release of the rubber plug, as well as the opening and closing of the rubber plug sleeve indicator. Furthermore, the method allows for versatility with different sized casings by replacing the rubber plug sleeve and the lower connector.

[0026] The rubber plug sleeve indicator does not open through the cementing rubber plug, making the opening method more reliable. This avoids the inability to determine whether the rubber plug has fallen normally during construction, or the down-descent indicator device being prone to failure when opened through the rubber plug, making it impossible to accurately determine the rubber plug's falling status. Attached Figure Description

[0027] Figure 1 A schematic diagram of the double-annular channel cementing head of the present invention is shown;

[0028] Figure 2 A schematic diagram showing the double-annular channel cementing head of the present invention in the open state;

[0029] Figure 3 A perspective view showing an embodiment of the rubber plug sleeve for the double-annular channel cementing head of the present invention;

[0030] Figure 4 A schematic diagram showing the double-annular channel cementing head of the present invention with a rubber plug;

[0031] Figure 5 This diagram shows the downward flow of the double-annular channel cement head of the present invention with a rubber plug. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments and accompanying drawings. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0033] The accompanying drawings are not necessarily drawn to scale, and some parts may not be shown in the drawings.

[0034] This invention provides a double-annular channel cementing head, such as... Figures 1 to 4As shown, the device includes a body 3, a rubber stopper sleeve 7, a stopper pin device, and a tongue plate 14. The rubber stopper sleeve 7 is located inside the body 3 and is used to house the rubber stopper 19. A cavity is formed between the rubber stopper sleeve 7 and the body 3. A limiting ring 8 is provided on the outer wall of the rubber stopper sleeve 7. The stopper pin device can act on the limiting ring 8 to limit the rubber stopper sleeve 7. A hinge mechanism (not shown) is provided at the lower end of the rubber stopper sleeve 7. The middle part of the tongue plate 14 is hinged to the lower end of the rubber stopper sleeve 7 through the hinge mechanism. An abutment part (not shown) is provided on the inner wall of the body 3 so that the first end of the tongue plate 14 can abut against it.

[0035] The dual-annular channel cementing head of the present invention also includes a liquid inlet device 6, which is disposed on the body 3, and the liquid outlet 63 of the liquid inlet device 6 communicates with the interior of the rubber stopper sleeve 7. In one embodiment, the liquid inlet device 6 includes a liquid inlet seat 61 and a liquid inlet cylinder 62. The liquid inlet seat 61 is fixedly mounted on the cylinder wall of the body 3 outside the body 3, and the liquid inlet cylinder 62 is perpendicularly abutting against the cylinder wall of the body 3 and centrally disposed in the liquid inlet seat 61. The liquid inlet cylinder 62 has a liquid outlet 63. A liquid inlet through hole 31 is provided on the body 3 corresponding to the liquid inlet cylinder 62, and the liquid inlet cylinder 62 is sealed to the body 3. The liquid outlet 63 is aligned with the liquid inlet through hole 31 on the body 3.

[0036] The double-annular channel cementing head of the present invention also includes a rubber plug sleeve limiting tube 4. The lower inner diameter of the rubber plug sleeve limiting tube 4 is slightly larger than the outer diameter of the rubber plug sleeve 7, so that the upper end of the rubber plug sleeve 7 can be confined within the rubber plug sleeve limiting tube 4. A first circulation hole 5 is provided on the rubber plug sleeve limiting tube 4, and the first circulation hole 5 communicates with the outlet 63 of the liquid inlet device 6. The top end of the rubber plug sleeve 7 is located below the first circulation hole 5. In one embodiment, a pipe is provided between the liquid inlet through hole 31 of the body 3 and the first circulation hole 5 of the rubber plug sleeve limiting tube 4, communicating the outlet 63 of the liquid inlet device 6 with the first circulation hole 5. A second circulation hole 16 is provided on the rubber plug sleeve 7, and the distance of the second circulation hole 16 from the lower end of the rubber plug sleeve 7 is greater than the height of the rubber plug 19.

[0037] Along the direction from the rubber stopper sleeve limiting tube 4 to the rubber stopper sleeve 7, the outer surface of the limiting ring 8 gradually slopes towards the center of the limiting ring 8 to form a first inclined surface. The stop pin device includes a limiting post 9, an outer stop pin 10, an inner stop pin 11, and a stop pin handwheel 12. The first end of the limiting post 9 passes through the cylinder wall of the body 3 and enters the body 3, abutting against the first inclined surface of the limiting ring 8. The second end of the limiting post 9 is connected to the outer stop pin 10 and is supported by the outer stop pin 10, which can restrict the movement of the limiting post 9. The outer stop pin 10 is threaded to one end of the inner stop pin 11, and the other end of the inner stop pin 11 is connected to the stop pin handwheel 12. The rotation of the stop pin handwheel 12 can drive the inner stop pin 11 to move in a direction perpendicular to the cylinder wall of the body 3, so the inner stop pin 11 can move closer to or further away from the body 3. The movement of the inner stop pin 11 will drive the outer stop pin 10 to move in a direction perpendicular to the cylinder wall of the body 3. Rotation of the stop pin handwheel 12 causes the outer stop pin 10 to move closer to or further away from the rubber stopper sleeve 7, thereby causing the limiting post 9 to move closer to or further away from the rubber stopper sleeve 7. In other embodiments, the stop pin device may also employ other forms of stop pin structure including a retractable stop pin in a direction perpendicular to the cylinder wall of the body 3. The retractable stop pin can abut against and support the limiting ring 8, thereby maintaining the position of the limiting ring 8.

[0038] The rubber stopper sleeve 7 is cylindrical. A limiting ring 8 is disposed outside the rubber stopper sleeve 7 and surrounds the cylindrical wall of the rubber stopper sleeve 7, abutting against the inner wall of the body 3. A second circulation hole 16 is disposed on the cylindrical wall of the rubber stopper sleeve 7, located below the limiting ring 8. A straightening block 13 is disposed outside the rubber stopper sleeve 7, located below the second circulation hole 16, and is used to support and position the rubber stopper sleeve 7. The straightening block 13 and the second circulation hole 16 are respectively circumferentially equidistantly disposed on the rubber stopper sleeve 7. A hinge mechanism is disposed at the lower end of the rubber stopper sleeve 7, and the middle part of the tongue plate 14 is hinged to the lower end of the rubber stopper sleeve 7 through the hinge mechanism. The first end of the tongue plate 14 abuts against the abutment part disposed on the inner wall of the body 3, and the second end of the tongue plate 14 is located below the rubber stopper 19 inside the rubber stopper sleeve 7, such as... Figure 4 As shown. In one embodiment, as Figure 1 and Figure 2 As shown, the cross-section of the straightening block 13 is triangular, and one corner of the straightening block 13 abuts against the inner wall of the body 3. Preferably, there are four straightening blocks 13. In another embodiment, as shown... Figure 3 As shown, the cross-section of the straightening block 13 is approximately rectangular, and the long side of the straightening block 13 abuts against the inner wall of the body 3. There are four straightening blocks 13. In this embodiment, there are six second circulation holes 16. The lower end of the rubber stopper sleeve 7 protrudes outward to form a protrusion 72, and a limiting block 71 is provided in the protrusion 72. The hinge mechanism can be provided on the protrusion 72, on the limiting block 71, or on both the protrusion 72 and the limiting block 71. A notch is provided at the lower part of the protrusion 72 adjacent to the limiting block 71. The tongue plate 14 can enter the rubber stopper sleeve 7 through the notch.

[0039] The dual-annular channel cementing head of the present invention also includes a rubber plug sleeve indicator, which is connected to a limiting ring 8 and displays the travel distance of the limiting ring 8. In one embodiment, the rubber plug sleeve indicator includes a rubber plug sleeve indicator lever 17 and a rubber plug sleeve indicator pointer 18. The rubber plug sleeve indicator lever 17 extends into the body 3 and is connected to the limiting ring 8. The rubber plug sleeve indicator pointer 18 is connected to the rubber plug sleeve indicator lever 17 and is configured to control the position of the rubber plug sleeve indicator pointer 18 via the rubber plug sleeve indicator lever 17. The rubber plug sleeve indicator pointer 18 is located outside the cylinder wall of the body 3 and can be observed from outside the body 3. Under normal circumstances, the rubber plug sleeve indicator pointer 18 is in a horizontal state. When the limiting ring 8 moves downward, it pushes the rubber plug sleeve indicator lever 17 downward, thereby pushing the rubber plug sleeve indicator pointer 18 downward.

[0040] The double-annular channel cementing head of the present invention also includes a top cover 2 and a lower connector 15.

[0041] The top cover 2 is lid-shaped, and a cement head lifting hole 1 is provided on the top surface of the top cover 2. The top cover 2 is detachably fixed to the upper end of the body 3, and the top cover 2 is fixedly connected to the rubber stopper sleeve limiting tube 4, with the rubber stopper sleeve limiting tube 4 located inside the body 3. The rubber stopper sleeve limiting tube 4 and the top surface of the top cover 2 are an integral structure, and the rubber stopper sleeve limiting tube 4 is cylindrical, with its top end connected to the bottom surface of the top surface of the top cover 2. In another embodiment, the rubber stopper sleeve limiting tube 4 and the top surface of the top cover 2 are separate structures, with the rubber stopper sleeve limiting tube 4 fixed to the bottom surface of the top surface of the top cover 2 by fasteners.

[0042] The lower connector 15 is approximately cup-shaped. The upper inner wall of the lower connector 15 matches and is fixedly connected to the lower outer wall of the body 3. The internal space of the lower connector 15 is connected to the internal space of the body 3. When the rubber stopper 19 is placed in the rubber stopper sleeve 7, the rubber stopper 19 can fall into the internal space of the lower connector 15.

[0043] This invention provides a method for installing a rubber plug in a double-annular channel cementing head, achieved using the double-annular channel cementing head of this invention. A stop pin device limits the rubber plug sleeve 7 to a first position. When the rubber plug sleeve 7 is in the first position, the limiting pin 9 of the stop pin device abuts against the limiting ring 8, the rubber plug sleeve indicator 17 is connected to the limiting ring 8, and the rubber plug sleeve indicator pointer 18 is in a horizontal state. A rubber plug 19 is installed inside the rubber plug sleeve 7. First, circulating drilling fluid is injected; then cement is injected. When the cement injection volume meets the cementing requirements, the stop pin device is removed from limiting the rubber plug sleeve 7, the rubber plug sleeve 7 moves downward, pushes open the tongue plate 14, and the rubber plug 19 is released.

[0044] A preferred embodiment of the double-annular channel cementing head of the present invention, such as... Figure 4 and Figure 5As shown, the system includes a top cover 2, a main body 3, a rubber stopper sleeve limiting tube 4, two liquid inlet devices 6, a rubber stopper sleeve 7, a stopper pin device, a rubber stopper sleeve indicator, a tongue plate 14, a lower connector 15, and a rubber stopper 19. The top cover 2 is detachably fixedly connected to the upper end of the main body 3, and the top surface of the top cover 2 is fixedly connected to the rubber stopper sleeve limiting tube 4. The upper end of the rubber stopper sleeve 7 is movably placed inside the lower cylindrical wall of the rubber stopper sleeve limiting tube 4. The rubber stopper sleeve 7 and the rubber stopper sleeve limiting tube 4 are located inside the main body 3. The lower connector 15 is fixedly connected to the lower end of the main body 3. The rubber stopper 19 is inside the rubber stopper sleeve 7 and above the tongue plate 14. The liquid inlet devices 6, the stopper pin device, and the rubber stopper sleeve indicator are all fixedly connected to the main body 3 outside the main body 3 and spaced apart from each other around the main body 3. The liquid inlet devices 6 are located above the rubber stopper sleeve indicator and the stopper pin device, closer to the top cover 2. The rubber stopper sleeve indicator and the stopper pin device are located on both sides of the main body 3. The rubber stopper display lever 17 of the rubber stopper display is connected to the limiting ring 8 of the rubber stopper 7, and the first end of the limiting post 9 of the stopper device abuts against the lower part of the limiting ring 8. The middle part of the tongue plate 14 is hinged to the lower end of the rubber stopper 7 through a hinge mechanism provided at the lower end of the rubber stopper 7. The first end of the tongue plate 14 abuts against the abutting part provided on the inner wall of the body 3, and the second end of the tongue plate 14 is inside the rubber stopper 7. Two liquid inlet devices 6 are located on both sides of the body 3. The liquid inlet cylinder 62 of the liquid inlet device 6 is provided on the cylinder wall of the body 3 through the liquid inlet seat 61. The liquid outlet 63 of the liquid inlet cylinder 62 is connected to the inside of the rubber stopper 7 through the liquid inlet through hole 31 on the body 3, the pipe between the body 3 and the rubber stopper limiting tube 4, and the first circulation hole 5 on the rubber stopper limiting tube 4. The limiting ring 8 of the rubber stopper sleeve 7 abuts against the inner wall of the body 3. The six second circulation holes 16 on the rubber stopper sleeve 7 are located below the limiting ring 8 and are farther from the lower end of the rubber stopper sleeve 7 than the height of the rubber stopper 19. The second circulation holes 16 connect the internal space of the rubber stopper sleeve 7 with the cavity between the rubber stopper sleeve 7 and the body 3. The four straightening blocks 13 below the second circulation holes 16 support and position the rubber stopper sleeve 7. The stopper device also includes an outer stopper pin 10, an inner stopper pin 11, and a stopper handwheel 12. The second end of the limiting post 9 is connected to the outer stopper pin 10. The outer stopper pin 10 is threaded to one end of the inner stopper pin 11, and the other end of the inner stopper pin 11 is connected to the stopper handwheel 12. The rubber stopper display dial 17 of the rubber stopper display is connected to the rubber stopper display pointer 18 located outside the body 3.

[0045] When the rubber stopper 19 is in its initial position, an outer ring channel is formed through the liquid outlet 63, the first circulation hole 5, the rubber stopper sleeve limiting tube 4 and the internal space of the rubber stopper sleeve 7, the second circulation hole 16, the cavity between the rubber stopper sleeve 7 and the body 3, and the internal space of the lower connector 15. Figure 4 As shown by the first arrow and broken line 20 in the diagram. When the rubber stopper 19 is in the downward position, an inner ring channel is formed through the liquid outlet 63, the first circulation hole 5, the internal space of the rubber stopper sleeve limiting tube 4 and the rubber stopper sleeve 7, and the internal space of the lower connector 15, as shown in the diagram. Figure 5 The second arrowhead is shown as line 21.

[0046] The double-annular channel cementing head of this invention can be used during cementing operations in the drilling and completion process. Before using the double-annular channel cementing head, the rubber plug 19 needs to be pre-installed in the rubber plug sleeve 7, and the lower end of the lower connector 15 of the double-annular channel cementing head needs to be connected to the casing. The process of using the double-annular channel cementing head in cementing operations is as follows: Figure 4 and Figure 5 As shown, it includes the following steps:

[0047] Step 1: Circulate drilling fluid. The drilling fluid enters the rubber stopper 7 through the outlet 63 of the inlet device 6 and the first circulation hole 5 on the rubber stopper limiting tube 4, and then enters the cavity between the rubber stopper 7 and the body 3 through the second circulation hole 16 on the rubber stopper 7. Finally, the drilling fluid enters the casing through the lower connector 15. Figure 4 The first arrow and broken line 20 in the diagram indicate the direction of drilling fluid flow.

[0048] Step 2: Inject cement slurry. The cement slurry enters the rubber plug sleeve 7 through the outlet 63 and the first circulation hole 5. When the cement slurry injection volume meets the cementing requirements, the inner stop pin 11 moves away from the body 3 by rotating the stop pin handwheel 12 of the stop pin device, which in turn moves the outer stop pin 10 away from the body 3. The rubber plug sleeve 7 moves downward under its own weight and the push of the injected cement slurry. The limiting ring 8 of the rubber plug sleeve 7 pushes the limiting column 9 downward until the lower end of the limiting column 9 abuts against the outer stop pin 10. Under the downward pushing action of the rubber plug sleeve 7, the tongue plate 14 disengages and opens, and the rubber plug 19 moves downward inside the rubber plug sleeve 7. At the same time, the limiting ring 8 pushes the rubber plug sleeve indicator dial 17 of the rubber plug sleeve indicator downward and drives the rubber plug sleeve indicator pointer 18 downward. The downward movement of the rubber plug sleeve indicator pointer 18 is observed from the outside to confirm that the rubber plug 19 has passed.

[0049] The dual-annular channel cementing head and plug installation method of this invention avoids the problem of damage to the plug sealing ring caused by contact between the plug sleeve indicator 17 and the limiting post 9 and the limiting ring 8 of the plug sleeve, as in traditional cementing heads. The plug sleeve 7 and the main body 3 form the dual channels of the dual-annular channel cementing head. The plug sleeve 7 enables the installation and release of the plug 19, and also enables the opening and closing of the plug sleeve indicator. Furthermore, the method allows for versatility with different sized casings by replacing the plug sleeve 7 and the lower connector 15.

[0050] The above embodiments merely illustrate implementation methods of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention.

Claims

1. A double-ring channel cementing head, characterized in that, Includes the body, rubber stopper sleeve, retaining pin device, and tongue plate. The rubber stopper sleeve is located inside the body and is used to house the rubber stopper. A cavity is formed between the rubber stopper sleeve and the body. A limiting ring is provided on the outer wall of the rubber stopper sleeve, and the limiting ring abuts against the inner wall of the body. The stop pin device can act on the limiting ring to limit the rubber plug sleeve; The lower end of the rubber stopper sleeve is provided with a hinge mechanism, and the middle part of the tongue plate is hinged to the lower end of the rubber stopper sleeve through the hinge mechanism. The inner wall of the body is provided with an abutting part that allows the first end of the tongue plate to abut against the stopper. The second end of the tongue plate is located inside the rubber stopper sleeve below the rubber stopper. The double-ring channel cementing head also includes a rubber plug sleeve limiting tube, on which a first circulation hole is provided, and the top of the rubber plug sleeve is located below the first circulation hole. The rubber stopper sleeve is provided with a second circulation hole. The distance between the second circulation hole and the lower end of the rubber stopper sleeve is greater than the height of the rubber stopper. The second circulation hole is located below the limiting ring. Along the direction from the rubber stopper sleeve limiting tube to the rubber stopper sleeve, the outer surface of the limiting ring gradually slopes towards the center of the limiting ring to form a first inclined surface; The stop pin device includes a limiting post, an outer stop pin, an inner stop pin, and a stop pin handwheel. The first end of the limiting post passes through the body cylinder wall and enters the body, abutting against the first inclined surface. The second end of the limiting post is connected to the outer stop pin. The outer stop pin is threadedly connected to one end of the inner stop pin. The other end of the inner stop pin is connected to the stop pin handwheel. The rotation of the stop pin handwheel causes the limiting post to move closer to or further away from the rubber stopper sleeve.

2. The double-annular channel cement head according to claim 1, characterized in that, It also includes a liquid inlet device, which is disposed on the main body and the liquid outlet of the liquid inlet device is connected to the inside of the rubber stopper sleeve.

3. The double-annular channel cement head according to claim 2, characterized in that, The upper end of the rubber stopper sleeve can be confined within the rubber stopper sleeve limiting tube; The first circulation hole is connected to the liquid outlet of the liquid inlet device.

4. The double-annular channel cementing head according to claim 1, characterized in that, It also includes a rubber stopper display, which is connected to the limiting ring and displays the travel distance of the limiting ring.

5. The double-annular channel cement head according to claim 4, characterized in that, The rubber stopper display includes a rubber stopper display lever and a rubber stopper display pointer. The rubber stopper display lever extends into the body and is connected to the limiting ring. The rubber stopper display pointer is connected to the rubber stopper display lever and is configured to control the position of the rubber stopper display pointer through the rubber stopper display lever.

6. The double-annular channel cementing head according to claim 2, characterized in that, The liquid inlet device includes an inlet seat and an inlet cylinder. The inlet seat is fixedly installed on the cylinder wall of the main body outside the main body. The inlet cylinder is perpendicular to the cylinder wall of the main body and centrally located in the inlet seat. The inlet cylinder has the liquid outlet.

7. The double-annular channel cement head according to claim 1, characterized in that, It also includes a top cover and a bottom connector, the top cover being detachably fixed to the upper end of the body, and the upper end of the bottom connector being fixedly fixed to the lower end of the body.

8. A method for installing a rubber plug in a double-annular channel cementing head, characterized in that, This is achieved using a double-annular channel cement head as described in any one of claims 1-7.

9. The method according to claim 8, characterized in that, The stop pin device limits the rubber plug sleeve to the first position, and the rubber plug sleeve is installed inside the rubber plug sleeve. First, the circulating drilling fluid is injected. Then cement is injected. When the amount of cement injected meets the cementing requirements, the retaining pin device is removed from the rubber plug sleeve. The rubber plug sleeve moves down, pushes open the tongue plate, and the rubber plug is released.

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