A cement head sealing system

Abstract

This utility model relates to a cement head sealing system, including a sealing door, a door hinge assembly, a spherical pressure-bearing part, and a shear pin assembly. The sealing door is rotatably mounted on the door hinge assembly, which is rotatably mounted on the cement head housing. The spherical pressure-bearing part is located on the inner side of the sealing door. The sealing door can rotate to close a cavity in the cement head housing, with the spherical surface of the pressure-bearing part located at the opening of the cavity. The shear pin assembly can detachably connect the sealing door and the cement head housing when the sealing door is closed, thereby locking the sealing door. Its advantages are that, through optimized force transmission of the spherical pressure-bearing part, flexible rotation of the hinge assembly, efficient locking and pressure relief function of the shear pin assembly, and structural integration of the sealing door, a synergistic improvement in high-pressure adaptability, operational efficiency, and safety performance is achieved, making it suitable for various complex cementing conditions.

Description

Technical Field

[0001] This utility model relates to the field of oil and gas field cementing technology, and in particular to a cementing head sealing system. Background Technology

[0002] In oil and gas cementing operations, the double-plug cement head is a key device for achieving two-stage cementing isolation. The ease of operation, pressure-bearing reliability, and safety protection of its sealing system directly determine the operational efficiency and construction safety.

[0003] Currently, existing cement head sealing systems have several limitations. For example, a cement head for oil extraction disclosed in publication number CN118309389A has a cumbersome sealing and cement plug installation process. It requires manual intervention: first, the top sealing cap must be opened, the trapezoidal thread loosened, then the lower retaining pin manually rotated into place, the lower rubber plug inserted, and then the upper retaining pin manually rotated again before inserting the upper rubber plug. Finally, the sealing cap is screwed on tightly. During this process, because the sealing cap uses a screw-tightening method, relative friction between the O-ring and the sealing surface is unavoidable, easily leading to seal wear. To ensure sealing reliability, two O-rings are usually required for redundant protection, which not only increases component costs but also increases maintenance workload due to frequent seal replacements.

[0004] With the increasing demands for operational efficiency and safety in cementing processes, traditional sealing structures can no longer meet the requirements of double-plug cementing operations that require frequent opening and closing. There is an urgent need for a cement head sealing system that combines efficient opening and closing with reliable sealing. Utility Model Content

[0005] (a) Technical problems to be solved

[0006] In view of the above-mentioned shortcomings and deficiencies of the prior art, this utility model provides a cement head sealing system for cementing, which solves the technical problem that the sealing effect of the prior art is difficult to meet the cementing requirements and affects the efficiency of cementing operations.

[0007] (II) Technical Solution

[0008] To achieve the above objectives, the main technical solutions adopted by this utility model include:

[0009] This utility model provides a cement head sealing system, including a sealing door, a door hinge assembly, a spherical pressure-bearing part, and a shear pin assembly. The sealing door is rotatably mounted on the door hinge assembly, which is rotatably mounted on the cement head housing. The spherical pressure-bearing part is disposed on the inner side of the sealing door. The sealing door can rotate to close the cavity in the cement head housing. The spherical surface of the spherical pressure-bearing part is located at the opening of the cavity. The shear pin assembly can detachably connect the sealing door and the cement head housing when the sealing door is closed, so as to lock the sealing door.

[0010] Optionally, the door hinge assembly includes a hinge base and a connecting leaf; one end of the hinge base is hinged to the cement head housing, the other end of the hinge base is hinged to one end of the connecting leaf, and the other end of the connecting leaf is hinged to the sealing door.

[0011] Optionally, the shear pin assembly includes a first shear pin and a second shear pin; the sealing door has a first pin hole and a second pin hole. When the sealing door is closed, the first pin hole is connected to the first insertion hole on the cement head housing, and the second pin hole is connected to the second insertion hole on the cement head housing. The first shear pin can pass through the first pin hole and the first insertion hole, and the second shear pin can pass through the second pin hole and the second insertion hole.

[0012] Optionally, the first and second pin holes of the sealing door are perpendicular to each other.

[0013] Optionally, there are two first pin holes and two second pin holes; the two first pin holes are arranged vertically and the two second pin holes are arranged horizontally, forming a rectangle; there are two first shear pins and two second shear pins.

[0014] Optionally, a guide seat is provided on the outside of the sealing door; the guide seat is slidably connected to a guide pin extending axially on the cement head housing.

[0015] Optionally, a flange is provided in the middle of the sealing door; the translation drive assembly of the cement head can be connected to the flange, and the drive shaft of the translation drive assembly can be inserted into the cavity of the cement head housing through the through hole on the flange.

[0016] Optionally, a handle is provided on the outside of the sealed door.

[0017] Optionally, a sealing ring is also provided on the sealing door to improve the sealing performance between the sealing door and the cement head housing.

[0018] (III) Beneficial Effects

[0019] The beneficial effects of this utility model are:

[0020] This utility model provides a cement head sealing system with a door hinge assembly that supports dual rotation of the sealing door (rotation of the sealing door relative to the hinge, and rotation of the hinge relative to the housing), significantly expanding the opening and closing angle and trajectory range. It is suitable for confined spaces such as offshore platforms and cluster well groups. Combined with the lightweight sealing door, manual opening and closing is less strenuous, especially reducing operational difficulty and safety risks during high-altitude operations. The spherical pressure-bearing part on the inner side of the sealing door enhances its pressure-bearing capacity. The mechanical properties of its spherical structure evenly distribute the impact force of high-pressure mud throughout the contact area, avoiding deformation of the sealing surface caused by localized stress concentration. Simultaneously, while ensuring the sealing door's own rigidity (resistance to deformation), the spherical pressure-bearing part reduces redundant materials through structural optimization, lightening the sealing door's weight and achieving a balance between lightweight and high pressure resistance, making it suitable for harsh working conditions such as deep wells and high-pressure wells. Furthermore, the spherical pressure-bearing part, serving as the contact surface between the sealing door and the cement head cavity opening, acts as a natural guide during the closing process. Its spherical curvature automatically corrects minor deviations, ensuring precise alignment of the sealing door. This allows the sealing door to close and lock quickly and accurately even under complex conditions, improving operational efficiency. The shear pin assembly achieves rapid locking when the sealing door closes. During operation, simply releasing the shear pin assembly allows for quick opening and closing of the sealing door, significantly shortening the time for installing and removing the filler core assembly and replacing the cement plug, further improving operational efficiency. Moreover, the spherical pressure-bearing part optimizes the force transmission path, ensuring a more uniform distribution of shear force on the shear pin assembly when mud pressure abnormally increases. Compared to existing technologies, this technology achieves a synergistic improvement in high-pressure adaptability, operational efficiency, and safety performance through optimized force transmission of the spherical pressure-bearing part, flexible rotation of the hinge assembly, efficient locking and pressure relief functions of the shear pin assembly, and the structural integration of the sealing door, making it suitable for various complex cementing conditions. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the cement head sealing system installed at the cement head in Embodiment 1 of this utility model;

[0022] Figure 2 for Figure 1 Enlarged view of point A in the middle;

[0023] Figure 3 This is a front view schematic diagram of the cement head sealing system in Embodiment 1 of this utility model;

[0024] Figure 4 This is a side view schematic diagram of the cement head sealing system in Embodiment 1 of this utility model;

[0025] Figure 5 This is a cross-sectional schematic diagram of the sealed door in Embodiment 1 of this utility model when it is opened;

[0026] Figure 6This is a cross-sectional schematic diagram of the sealing door in Embodiment 1 of this utility model when it is closed.

[0027] [Explanation of Labels in the Attached Image]

[0028] 1: Sealing door; 11: First pin hole; 12: Second pin hole; 13: Guide seat; 14: Flange; 15: Sealing plug; 2: Spherical pressure bearing part; 3: Hinge seat; 4: Connecting leaf; 5: First shear pin; 6: Second shear pin; 7: Handle; 8: Sealing ring. Detailed Implementation

[0029] To better understand the above technical solutions, exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present invention are shown in the drawings, it should be understood that the present invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that the present invention can be understood more clearly and thoroughly, and that the scope of the present invention can be fully conveyed to those skilled in the art.

[0030] Example 1:

[0031] like Figure 1 and Figure 2 As shown, this embodiment provides a cement head sealing system, including a sealing door 1, a door hinge assembly, a spherical pressure-bearing part 2, and a shear pin assembly. The sealing door 1 is rotatably mounted on the door hinge assembly, which is rotatably mounted on the cement head housing. The spherical pressure-bearing part 2 is disposed on the inner side of the sealing door 1. The sealing door 1 can rotate to close the cavity in the cement head housing. The spherical surface of the spherical pressure-bearing part 2 is located at the opening of the cavity. The shear pin assembly can detachably connect the sealing door 1 and the cement head housing when the sealing door 1 is closed, so as to lock the sealing door 1.

[0032] Specifically, the door hinge assembly supports dual rotation of the sealed door 1 (rotation of the sealed door 1 relative to the hinge, and rotation of the hinge relative to the housing), significantly expanding the opening and closing angle and trajectory range. It is suitable for confined spaces such as offshore platforms and well clusters, and, combined with the lightweight sealed door 1, makes manual opening and closing easier, especially reducing operational difficulty and safety risks during high-altitude operations. The spherical pressure-bearing part 2 on the inner side of the sealed door 1 enhances its pressure-bearing capacity. Its spherical structure's mechanical properties evenly distribute the impact force of high-pressure mud throughout the contact area, preventing deformation of the sealing surface caused by localized stress concentration. Simultaneously, while ensuring the rigidity (resistance to deformation) of the sealed door 1, the spherical pressure-bearing part 2 reduces redundant materials through structural optimization, lightening the door 1's weight and achieving a balance between lightweight and high pressure resistance, making it suitable for harsh working conditions such as deep wells and high-pressure wells. Furthermore, the spherical pressure-bearing part 2, serving as the contact surface between the sealing door 1 and the cement head cavity opening, acts as a natural guide during the closing process. Its spherical curvature automatically corrects minor deviations, ensuring precise alignment of the sealing door 1. This allows the sealing door 1 to close and lock quickly and accurately even under complex working conditions, improving operational efficiency. The shear pin assembly achieves rapid locking when the sealing door 1 closes. During operation, simply releasing the shear pin assembly allows for quick opening and closing of the sealing door 1, significantly shortening the time for loading and unloading the filler assembly and replacing the cement plug, thus improving operational efficiency. Moreover, the spherical pressure-bearing part 2 optimizes the force transmission path, ensuring a more uniform distribution of shear force on the shear pin assembly when mud pressure abnormally increases. Compared to existing technologies, this technology achieves a synergistic improvement in high-pressure adaptability, operational efficiency, and safety performance through optimized force transmission of the spherical pressure-bearing part 2, flexible rotation of the hinge assembly, efficient locking and pressure relief functions of the shear pin assembly, and the structural integration of the sealing door 1, making it suitable for various complex cementing conditions.

[0033] Furthermore, such as Figures 1-3 As shown, the door hinge assembly includes a hinge base 3 and a connecting leaf 4. One end of the hinge base 3 is hinged to the cement head housing, and the other end of the hinge base 3 is hinged to one end of the connecting leaf 4. The other end of the connecting leaf 4 is hinged to the sealing door 1. The multi-joint design of the hinge base 3 and the connecting leaf 4 makes the opening and closing trajectory of the sealing door 1 more flexible, allowing for a larger angle of rotation. This avoids interference between the sealing door 1 and the cement head housing or other equipment components during opening and closing, making it particularly suitable for the operational needs of space-constrained scenarios such as offshore platforms. The multi-joint hinge ensures that the spherical pressure-bearing part 2 can be precisely aligned with the opening of the cement head cavity, avoiding misalignment of the sealing surface caused by excessive hinge rigidity, and indirectly enhancing sealing reliability. The joint force is distributed and transmitted through multiple hinge points of the hinge base 3 and the connecting leaf 4, reducing the force concentration on a single hinge axis, reducing wear caused by long-term rotation, and extending the service life of the hinge assembly.

[0034] Furthermore, such as Figures 2-4As shown, the shear pin assembly includes a first shear pin 5 and a second shear pin 6. The sealing door 1 has a first pin hole 11 and a second pin hole 12. When the sealing door 1 is closed, the first pin hole 11 communicates with the first insertion hole on the cement head housing, and the second pin hole 12 communicates with the second insertion hole on the cement head housing. The first shear pin 5 can pass through the first pin hole 11 and the first insertion hole, and the second shear pin 6 can pass through the second pin hole 12 and the second insertion hole. The first shear pin 5 and the second shear pin 6 lock the sealing door 1 from two points, preventing premature failure of a single shear pin due to vibration and wear, ensuring uniform contact pressure between the sealing door 1 and the installation cavity opening, and further improving sealing reliability under high pressure. The two sets of shear pins share the impact force of the mud on the sealing door 1, avoiding local deformation caused by concentrated force on a single pin, and extending the service life of the shear pin assembly. Simultaneously, the dual-point positioning ensures the sealing door 1 is in a correct posture when closed, preventing leakage from the sealing surface gap due to skewness. Furthermore, when the pressure inside the installation cavity exceeds the design threshold (such as an abnormal increase in mud pressure), the first shear pin 5 and the second shear pin 6 will be sheared by the shearing force of the sealing door 1. The sealing door 1 will automatically open to release pressure, preventing damage to the inner tank body or cement head shell due to overpressure. This provides passive safety protection for the equipment and operators, and solves the problem of traditional end door locking being too tight, which can easily lead to structural overload. In this embodiment, the first pin hole 11 and the second pin hole 12 of the sealing door 1 are perpendicular to each other. The vertically arranged first pin hole 11 and second pin hole 12 enable the first shear pin 5 and the second shear pin 6 to bear forces in different directions. When the mud impact causes the sealing door 1 to be subjected to complex loads (such as torsion and lateral force), the first shear pin 5 and the second shear pin 6 can bear the load specifically, ensuring that the shearing action is triggered according to the design threshold, and avoiding shearing failure caused by a single force direction. Specifically, there are two first pin holes 11 and two second pin holes 12. The two first pin holes 11 extend vertically, and the two second pin holes 12 extend horizontally, forming a rectangle. Similarly, there are two first shear pins 5 and two second shear pins 6. The two first shear pins 5 and two second shear pins 6 are evenly distributed on the sealing door 1. When the sealing door 1 is subjected to high-pressure mud impact, the rectangular layout can distribute the impact force to the four shear pins, avoiding premature breakage or local deformation of the sealing door 1 caused by concentrated force on a single pin, significantly improving the load-bearing capacity of the locking structure and adapting to high-pressure cementing conditions. During cementing operations, the mud flow field may generate lateral impact force or torsional moment on the sealing door 1. The two first shear pins 5 and two second shear pins 6 with rectangular layout form a rigid frame effect through dual constraints in the horizontal and vertical directions (such as the two first shear pins 5 resisting torsion in the vertical direction and the two second shear pins 6 resisting lateral force in the horizontal direction), which effectively offsets non-axial loads and prevents the sealing door 1 from loosening slightly due to torque in the locked state, thus maintaining long-term sealing performance.In practical use, after the sealing door 1 is in place, first insert the second shear pin 6 horizontally, and then insert the first shear pin 5 vertically.

[0035] Furthermore, such as Figure 2 and Figure 4 As shown, a guide seat 13 is provided on the outer side of the sealing door 1; the guide seat 13 is slidably connected to a guide pin extending axially on the cement head housing. When the guide seat 13 slides along the guide pin, it provides auxiliary guidance for the sliding of the sealing door 1, ensuring that the sealing door 1 moves along a preset path during closing, avoiding deflection caused by gravity or external forces, and reducing the workload of manual calibration. The sliding fit reduces the shaking of the sealing door 1 when it rotates, reduces the force fluctuation of the hinge assembly, and at the same time, the contact between the guide pin and the guide seat 13 can share part of the radial load, extending the service life of the hinge.

[0036] Furthermore, such as Figures 3-6 As shown, a flange 14 is provided in the middle of the sealing door 1; the translation drive assembly of the cement head can be connected to the flange 14, and the drive shaft of the translation drive assembly can pass through the through hole on the flange 14 into the cavity of the cement head shell. The flange 14 realizes the integrated connection between the translation drive assembly and the sealing door 1. The drive shaft can enter the cavity without additional holes in the cement head shell, avoiding weak points in the seal caused by additional holes, and ensuring that the slurry does not leak under high pressure. The driving force is directly transmitted through the flange 14, reducing transmission loss and making the sliding control of the core assembly more precise; at the same time, it simplifies the equipment layout, avoids spatial interference between the drive system and the sealing system, and improves the overall structural compactness. Specifically, the cement head cavity is usually provided with two openings, both of which are sealed by the sealing door 1. The translation drive assembly can be connected to the sealing door 1 at one end of the cement head shell. For the sealing door 1 at the other end of the cement head shell, the through hole on the flange 14 of the sealing door 1 is also equipped with a sealing plug 15. The through hole is closed by the sealing plug 15 to form a complete seal. The sealing plug 15 and the through hole adopt an interference fit or threaded sealing structure, which can effectively prevent mud leakage from the through hole and ensure the sealing consistency at both ends of the cavity. At the same time, the sealing plug 15 is detachable, and the translation drive assembly can be selectively connected to either sealing door 1. Through the flexible configuration of installing the drive at one end and sealing at the other end, the simplicity of the drive system layout and the upgradeability of the equipment are taken into account while ensuring the integrity of the seal, further optimizing the overall structural rationality and ease of use of the cement head.

[0037] Furthermore, such as Figure 4As shown, a sealing ring 8 is also provided on the sealing door 1. The sealing ring 8 is used to improve the sealing performance between the sealing door 1 and the cement head shell. The sealing ring 8 can close the tiny gap between the sealing door 1 and the cement head shell, improving the sealing reliability. When the sealing door 1 slides along the guide pin, the sealing door 1 closes according to a preset trajectory, so that the relative friction of the sealing ring 8 when it contacts the sealing surface of the shell is controlled at an extremely low level, avoiding tearing or curling caused by lateral sliding. This trajectory control, in conjunction with the guiding characteristics of the spherical pressure bearing part 2, significantly extends the service life of the sealing ring after a single installation. The single sealing ring is made of highly elastic rubber material. When the mud pressure fluctuation causes the sealing door 1 to produce a slight axial displacement, the sealing ring 8 adaptively expands and contracts with the displacement, avoiding permanent deformation due to excessive compression. This elastic compensation mechanism, in conjunction with the rigid locking of the rectangular layout four shear pins, enables the sealing system to maintain a stable seal within the common pressure fluctuation range.

[0038] Furthermore, such as Figure 4 As shown, a handle 7 is provided on the outside of the sealed door 1, providing a clear point of force for manual opening and closing of the sealed door 1. Especially when the sealing door 1 is contaminated with mud or subjected to high pressure, resulting in greater opening resistance, tools (such as wrenches) can be used to assist in the operation, reducing the intensity of manual labor and shortening the opening and closing time.

[0039] The cement head sealing system provided in this embodiment is used as follows: Before operation, the integrity of the spherical pressure-bearing part 2 and the sealing ring 8 on the inner side of the sealing door 1 is checked according to the opening size of the cement head cavity to ensure that there is no damage or aging. When closing the sealing door 1, the sealing door 1 is rotated by the outer handle 7, so that the guide seat 13 slides along the guide pin of the cement head shell, and the sealing door 1 is accurately closed by means of the guiding action. After the spherical pressure-bearing part 2 enters the cavity opening, two second shear pins 6 (pin holes in the horizontal direction) are first inserted horizontally, and then two first shear pins 5 (pin holes in the vertical direction) are inserted vertically. The four shear pins form a rectangular locking layout to complete the fixing of the sealing door 1. At this time, the sealing ring 8 naturally fits the sealing surface under the pressure of the sealing door 1, forming a double sealing protection. The drive shaft of the translation drive assembly is passed through the flange 14 through hole of one end of the sealing door 1 and fixedly connected by the flange 14. The flange 14 through hole of the other end of the sealing door 1 is sealed with a sealing plug 15 to ensure that both ends are sealed. During operation, high-pressure mud is injected into the cement head cavity. The spherical pressure-bearing part 2 tightly fits the opening under pressure. The sealing ring 8 adapts to the slight axial displacement that may occur in the sealing door 1, compressing or rebounding, and always maintaining a sealed state.

[0040] Example 2:

[0041] This embodiment provides a cementing head, including a shell, an inner liner, a core-filling assembly, a translation drive assembly, and the sealing system described in Embodiment 1. The inner liner is disposed inside the shell and has a laterally extending mounting cavity. The core-filling assembly is laterally slidably disposed in the inner liner. The mounting cavity has openings at both ends, and a sealing system is provided at each opening. A sealing door 1 is rotatably mounted on the shell via a door hinge, and the sealing door 1 can rotate to seal the opening of the corresponding mounting cavity.

[0042] In the description of this utility model, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0043] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in this utility model can be understood according to the specific circumstances.

[0044] In this utility model, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "beneath" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0045] In the description of this specification, the terms "one embodiment," "some embodiments," "embodiment," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0046] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make modifications, alterations, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A cement head sealing system for well cementing, characterized in that, It includes a sealed door (1), a door hinge assembly, a spherical pressure-bearing part (2), and a shear pin assembly; The sealed door (1) is rotatably mounted on the door hinge assembly, which is rotatably mounted on the cement head housing, and the spherical pressure bearing part (2) is provided on the inner side of the sealed door (1). The sealing door (1) can rotate to close the cavity in the cement head housing. The spherical pressure bearing part (2) is located at the opening of the cavity. The shear pin assembly can detachably connect the sealing door (1) and the cement head housing when the sealing door (1) is closed, so as to lock the sealing door (1).

2. The cement head sealing system as described in claim 1, characterized in that, The door hinge assembly includes a hinge base (3) and a connecting page (4); One end of the hinge seat (3) can be hinged to the cement head shell, and the other end of the hinge seat (3) is hinged to one end of the connecting page (4), and the other end of the connecting page (4) is hinged to the sealing door (1).

3. The cement head sealing system as described in claim 1, characterized in that, The shear pin assembly includes a first shear pin (5) and a second shear pin (6); The sealing door (1) has a first pin hole (11) and a second pin hole (12). When the sealing door (1) is closed, the first pin hole (11) is connected to the first insertion hole on the cement head shell, and the second pin hole (12) is connected to the second insertion hole on the cement head shell. The first shear pin (5) can pass through the first pin hole (11) and the first insertion hole, and the second shear pin (6) can pass through the second pin hole (12) and the second insertion hole.

4. The cement head sealing system as described in claim 3, characterized in that, The first pin hole (11) and the second pin hole (12) of the sealing door (1) are perpendicular to each other.

5. The cement head sealing system as described in claim 4, characterized in that, The number of first pin holes (11) and second pin holes (12) are both two; Two first pin holes (11) are arranged vertically, and two second pin holes (12) are arranged horizontally. The two first pin holes (11) and the two second pin holes (12) together form a rectangle. There are two of each of the first shear pin (5) and the second shear pin (6).

6. The cement head sealing system as described in claim 1, characterized in that, A guide seat (13) is provided on the outside of the sealed door (1); The guide seat (13) is slidably connected to the guide pin extending axially on the cement head housing.

7. The cement head sealing system as described in claim 1, characterized in that, A flange (14) is provided in the middle of the sealed door (1); The translation drive assembly of the cement head can be connected to the flange (14), and the drive shaft of the translation drive assembly can be inserted into the cavity of the cement head housing through the through hole on the flange (14).

8. The cement head sealing system as described in claim 1, characterized in that, A handle (7) is provided on the outside of the sealed door (1).

9. The cement head sealing system as described in claim 1, characterized in that, A sealing ring (8) is also provided on the sealing door (1), which is used to improve the sealing between the sealing door (1) and the cement head shell.

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