Ultrahigh-pressure metal sealing casing head with self-locking function

Abstract

The invention discloses an ultrahigh-pressure metal sealing casing head with a self-locking function in the technical field of casing heads. The ultrahigh-pressure metal sealing casing head comprises a casing body, and a mounting through opening is formed in the casing body; in the petroleum drilling process, an extrusion ring and a sliding groove are utilized, the upper end of the extrusion ring is extruded through the sliding groove when the pressure intensity in a mounting pipe is increased, the clamping force of the extrusion ring on the mounting pipe can be increased, and it is guaranteed that the mounting pipe can be stably clamped by the extrusion ring when the pressure intensity in the mounting pipe is high; the situation that in the long-time use process of the installation pipe, high-pressure liquid in the installation pipe and the installation through opening can cause the installation pipe to be loosened, and consequently the installation pipe and the sleeve body are damaged is avoided, and the fastening block is used for fastening the installation pipe in the conveying process after the internal pressure intensity of the installation pipe is increased. And the jacking rod can be pulled to one side under the action of the fastening block to keep stable, and the situation that in the conveying process of the mounting pipe, the mounting pipe shakes, and consequently the jacking rod is loosened is avoided.

Description

Technical Field

[0001] The invention relates to the technical field of casing heads, in particular to an ultra-high pressure metal sealing casing head with a self-locking function. Background Art

[0002] The casing head is used to fix the wellhead of the drilled well, connect the wellhead casing string, support the gravity of the technical casing and the oil layer casing, seal the annular space between the layers of pipes, provide a transition connection for the installation of blowout preventers, tubing heads, and Christmas trees, and through the two side ports on the casing head body, operations such as mud squeezing, monitoring, and filling of balancing fluid can be carried out; the casing string is an important component in natural gas exploration and development, and plays an important role in the construction of underground gas storage wells; the casing string is a high-pressure container that is thousands of meters long and connected by casing one by one, and the threaded connection between two adjacent casings is the casing joint.

[0003] In the existing oil drilling process, it is usually necessary to install the casing head on the wellhead, and then the delivery pipe needs to be connected to the casing head. The casing head will fix and seal the delivery pipe. However, during the drilling process, the pressure in the delivery pipe is relatively high, and during the delivery of the delivery pipe, vibration will be generated between the delivery pipe and the casing head due to the high pressure. During long-term work, a gap is easily generated between the delivery pipe and the casing head, which may cause damage to the casing head and the delivery pipe. Summary of the invention

[0004] The purpose of the present invention is to provide an ultra-high pressure metal sealing casing head with a self-locking function to solve the problems raised in the above background technology.

[0005] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: an ultra-high pressure metal sealing casing head with a self-locking function, comprising a casing body, the casing body is provided with an installation port, a flat valve, a pressure gauge, a sealing groove and a mounting pipe, a limiting mechanism is provided on the surface of the casing body, the limiting mechanism is used to limit the mounting pipe, a sealing mechanism is provided on the surface of the mounting pipe, the sealing mechanism is used to seal between the mounting pipe and the casing body, an automatic clamping mechanism is provided inside the casing body, the automatic clamping mechanism is used to automatically clamp the mounting pipe when the internal pressure of the casing body increases during transportation after the mounting pipe is installed, a positioning mechanism is provided on the surface of the automatic clamping mechanism, the positioning mechanism is used to limit the position of the automatic clamping mechanism and the mounting pipe, a fastening mechanism is provided between the automatic clamping mechanism and the limiting mechanism, and the fastening mechanism is used to fasten the limiting mechanism when the automatic clamping mechanism clamps the mounting pipe.

[0006] As a further solution of the present invention, the limiting mechanism includes an annular limiting groove, the limiting groove is opened on the surface of the mounting tube, a plurality of threaded holes are opened on the surface of the sleeve body, a plurality of threaded holes are threadedly connected with a push rod, and the end of the push rod is located in the limiting groove.

[0007] As a further solution of the present invention, the sealing mechanism comprises an annular fixing strip, which is fixedly connected to the surface of the mounting tube. Two annular grooves are formed on the surface of the fixing strip, and sealing rings are arranged in the annular grooves.

[0008] As a further solution of the present invention, the automatic clamping mechanism includes an annular sliding groove, the sliding groove is opened on the inner wall surface of the installation opening, the top of the sliding groove is an inclined surface, an extrusion ring is slidably connected in the sliding groove, the upper end of the extrusion ring is an inclined surface, and the sealing ring is in contact with the inner side of the extrusion ring.

[0009] As a further solution of the present invention, the positioning mechanism includes an annular positioning groove, the positioning groove is opened on the surface of the mounting tube, a positioning strip is fixedly connected to the inner surface of the extrusion ring, and the upper end of the positioning strip is an inclined surface.

[0010] As a further solution of the present invention, the fastening mechanism includes a plurality of expanded holes, which are respectively opened on the inner side of the threaded hole close to the mounting opening, a fastening block is elastically and slidably connected in the expanded hole, the fastening block is conical on the side away from the mounting opening, the push rod passes through the fastening block and is threadedly connected to the fastening block, an extension groove is opened at the bottom of the inner wall of the expanded hole, the extension groove extends downward and communicates with the sliding groove, a fastening plate is elastically and slidably connected in the extension groove, the upper end of the fastening plate is arc-shaped, the upper end of the fastening plate is fitted with the inclined surface of the end of the fastening block, a retractable pushing block is fixedly connected to the surface of the extrusion ring, and the pushing block is located below the fastening plate.

[0011] As a further solution of the present invention, a plurality of obliquely arranged communicating holes are provided at the bottom of the sliding groove, and the communicating holes are communicated with the installation opening.

[0012] As a further solution of the present invention, the inner wall surface of the installation opening is provided with a plurality of arc grooves arranged at equal angles, the inner wall of the arc groove is an inclined surface, a positioning block is slidably connected in the plurality of arc grooves, a through opening is provided on the surface of the positioning block, and the through opening is located below the position of the connecting hole.

[0013] As a further solution of the present invention, a plurality of extrusion notches arranged at equal angles are provided on the upper end surface of the extrusion ring, and the bottom of the mounting tube is an inclined surface.

[0014] As a further solution of the present invention, a clearance groove is provided on the inner wall of the sliding groove on a side away from the installation opening.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] 1. The present invention utilizes an extrusion ring and a sliding groove during oil drilling. When the pressure in the installation pipe increases, the sliding groove is used to extrude the upper end of the extrusion ring, so that the extrusion ring can increase the clamping force on the installation pipe, ensuring that the installation pipe can be stably clamped by the extrusion ring when the pressure in the installation pipe is high, thereby preventing the installation pipe from being loosened due to high-pressure liquid in the installation pipe and the installation port during long-term use of the installation pipe, thereby damaging the installation pipe and the casing body. In addition, the fastening block is used to enable the push rod to be pulled to one side and kept stable under the action of the fastening block during transportation after the internal pressure of the installation pipe increases, thereby preventing the installation pipe from shaking during transportation, thereby causing the push rod to loosen and affecting the limit of the push rod on the installation pipe.

[0017] 2. In the process of conveying the installation tube of the present invention, the pressure in the installation port and the installation tube will increase, the pressure in the installation port will act on the bottom of the extrusion ring through the connecting hole, and the extrusion ring will move upward under the action of the pressure inside the installation port. When the pressure in the installation port increases, the upward force of the extrusion ring can be increased to ensure that the extrusion ring can quickly clamp the installation tube after the pressure in the installation port increases.

[0018] 3. According to the present invention, when the mounting tube is moved into the mounting opening, the mounting tube will move between a plurality of positioning blocks, and the plurality of positioning blocks can make the mounting tube be in the middle position in the mounting opening, and the positioning blocks can keep the mounting tube stable. In the subsequent use of the mounting tube, when the pressure in the mounting opening increases, the liquid in the mounting tube will act on the positioning blocks to move upward in the arc groove. The upward movement of the positioning blocks will move toward one side of the mounting tube under the action of the arc groove, and the mounting tube can be squeezed and clamped, so that the mounting tube can remain stable during transportation, thereby reducing the vibration of the mounting tube during operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0020] Figure 2 It is a schematic diagram of the overall structure of the present invention after being cut apart;

[0021] Figure 3 for Figure 2 Schematic diagram of the structure at A in the middle;

[0022] Figure 4 for Figure 2 Schematic diagram of the structure at B in the middle;

[0023] Figure 5It is a schematic diagram of the structure of the sleeve body and the installation pipe after being cut apart in the present invention;

[0024] Figure 6 It is a schematic diagram of the structure of the interior of the sleeve body and the automatic clamping mechanism in the present invention;

[0025] Figure 7 for Figure 6 Schematic diagram of the structure at C in the middle;

[0026] Figure 8 for Figure 6 Schematic diagram of the structure at D in the middle;

[0027] Fig. 9 for Figure 6 Schematic diagram of the structure at E in the middle;

[0028] Fig.10 It is a schematic diagram of the structure of the sleeve body after being cut open in the present invention;

[0029] Fig.11 for Fig.10 Schematic diagram of the structure at F in the middle;

[0030] Fig.12 for Fig.10 Schematic diagram of the structure at G in the middle;

[0031] Fig.13 It is a schematic diagram of the structure of the installation pipe in the present invention.

[0032] In the accompanying drawings, the components represented by the reference numerals are listed as follows:

[0033] 1-sleeve body, 2-installation port, 3-flat valve, 4-pressure gauge, 5-sealing groove, 6-installation pipe, 7-limiting groove, 8-threaded hole, 9-top rod, 10-fixing strip, 11-annular groove, 12-sealing ring, 13-sliding groove, 14-extrusion ring, 15-positioning groove, 16-positioning strip, 17-expansion hole, 18-fastening block, 19-extension groove, 20-fastening plate, 21-pushing block, 22-connecting hole, 23-arc groove, 24-positioning block, 25-through-hole, 26-extrusion notch, 27-allowance groove. DETAILED DESCRIPTION

[0034] The following describes the embodiments of the present invention by specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict.

[0035] It should be noted that the illustrations provided in the following embodiments are only used to illustrate the basic concept of the present invention in a schematic manner, and thus the illustrations only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0036] See also Figure 1-Figure 13 The present invention provides a technical solution: an ultra-high pressure metal sealing casing head with a self-locking function, comprising a casing body 1, an installation port 2 is opened inside the casing body 1, flat valves 3 are connected to the left and right sides of the casing body 1 surface, and a pressure gauge 4 is connected to the surface of the rightmost flat valve 3, a plurality of sealing grooves 5 are arranged inside the casing body 1, a mounting pipe 6 is arranged inside the casing body 1, a limiting mechanism is arranged on the surface of the casing body 1, the limiting mechanism is used to limit the mounting pipe 6, a sealing mechanism is arranged on the surface of the mounting pipe 6, and the sealing mechanism is used to seal between the mounting pipe 6 and the casing body 1, an automatic clamping mechanism is arranged inside the casing body 1, the automatic clamping mechanism is used to automatically clamp the mounting pipe 6 when the pressure inside the casing body 1 increases when the mounting pipe 6 is transported after installation, a positioning mechanism is arranged on the surface of the automatic clamping mechanism, the positioning mechanism is used to limit the position of the automatic clamping mechanism and the mounting pipe 6, a fastening mechanism is arranged between the automatic clamping mechanism and the limiting mechanism, and the fastening mechanism is used to fasten the limiting mechanism when the automatic clamping mechanism clamps the mounting pipe 6;

[0037] The limiting mechanism includes an annular limiting groove 7, which is provided on the surface of the mounting tube 6. A plurality of threaded holes 8 are provided on the surface of the sleeve body 1. A push rod 9 is threadedly connected in each of the plurality of threaded holes 8. The end of the push rod 9 is located in the limiting groove 7.

[0038] The sealing mechanism includes an annular fixing strip 10, which is fixedly connected to the surface of the mounting tube 6. Two annular grooves 11 are formed on the surface of the fixing strip 10, and a sealing ring 12 is arranged in the annular groove 11.

[0039] The automatic clamping mechanism includes an annular sliding groove 13, which is provided on the inner wall surface of the installation opening 2, the top of the sliding groove 13 is an inclined surface, an extrusion ring 14 is slidably connected in the sliding groove 13, the upper end of the extrusion ring 14 is an inclined surface, and the sealing ring 12 is in contact with the inner side of the extrusion ring 14;

[0040] The positioning mechanism includes an annular positioning groove 15, which is opened on the surface of the mounting tube 6. A positioning strip 16 is fixedly connected to the inner surface of the extrusion ring 14, and the upper end of the positioning strip 16 is an inclined surface.

[0041] The fastening mechanism includes a plurality of reaming holes 17, which are respectively arranged on the inner side of the threaded hole 8 near the mounting opening 2, and a fastening block 18 is elastically slidably connected in the reaming hole 17, and the fastening block 18 is tapered on the side away from the mounting opening 2, and the push rod 9 passes through the fastening block 18 and is threadedly connected with the fastening block 18, and an extension groove 19 is arranged at the bottom of the inner wall of the reaming hole 17, and the extension groove 19 extends downward and communicates with the sliding groove 13, and a fastening plate 20 is elastically slidably connected in the extension groove 19, and the upper end of the fastening plate 20 is arc-shaped, and the upper end of the fastening plate 20 is fitted with the inclined surface of the end of the fastening block 18, and a retractable pushing block 21 is fixedly connected to the surface of the extrusion ring 14, and the pushing block 21 is located below the fastening plate 20;

[0042] During the oil drilling process, the casing body 1 needs to be installed on the surface of the well, and the drilling end is sealed through the sealing groove 5. Then, after the casing body 1 is installed, one end of the installation tube 6 needs to be moved into the installation port 2. The installation tube 6 will drive the fixing strip 10 and the sealing ring 12 to move into the installation port 2. The fixing strip 10 and the sealing ring 12 will first move to the position of the extrusion ring 14. The sealing ring 12 will fit the inner side of the extrusion ring 14 to seal the extrusion ring 14 and the installation tube 6. When the installation tube 6 moves into the installation port 2, the positioning strip 16 will move into the positioning groove 15, and then adjust the installation tube 6. The position of the mounting tube 6 is adjusted so that the limiting groove 7 is located at the position of the push rod 9, and then the push rods 9 are rotated one by one to move the end of the push rod 9 into the limiting groove 7. Multiple push rods 9 can limit the mounting tube 6 from multiple positions. Then, during the transportation of the mounting tube 6, when the pressure in the mounting port 2 and the mounting tube 6 gradually increases, the mounting tube 6 will move upward under the action of the pressure, and the mounting ring will drive the extrusion ring 14 to move upward together. During the upward movement of the extrusion ring 14, the upper end of the extrusion ring 14 will move to the top of the sliding groove 13, and the upper end inclined surface of the extrusion ring 14 will be moved closer to the mounting ring 6 under the action of the top inclined surface of the sliding groove 13. The squeezing ring 14 can squeeze the upper end of the squeezing ring 14 by using the sliding groove 13 when the pressure in the mounting tube 6 increases, so that the squeezing ring 14 can increase the clamping force on the mounting tube 6, ensuring that the mounting tube 6 can be stably clamped by the squeezing ring 14 when the pressure in the mounting tube 6 is high, and avoiding that the high-pressure liquid in the mounting tube 6 and the mounting port 2 will cause the mounting tube 6 to loosen during the long-term use of the mounting tube 6, thereby damaging the mounting tube 6 and the sleeve body 1. In the process of the squeezing ring 14 moving upward, the squeezing ring 14 will drive the push block 21 to move upward together, and the push block 21 will move first When the fastening plate 20 reaches the bottom position, the pushing block 21 then moves upward to push the fastening plate 20 upward. The fastening plate 20 moves upward under the action of the pushing block 21. The upper end of the fastening plate 20 acts on the fastening block 18 to squeeze it to one side. The fastening block 18 pulls the push rod 9 through the threaded connection with the push rod 9. This is beneficial in the process of transportation after the internal pressure of the mounting tube 6 increases, so that the push rod can be pulled to one side under the action of the fastening block 18 to remain stable, thereby avoiding the shaking of the mounting tube 6 during the transportation process, thereby causing the push rod 9 to loosen and affecting the limit of the mounting tube 6 by the push rod 9.

[0043] During the transportation of the installation tube 6, the extrusion ring 14 can only move under the driving action of the installation tube 6. As a further solution of the present invention, a plurality of obliquely arranged communication holes 22 are provided at the bottom of the sliding groove 13, and the communication holes 22 are connected to the installation port 2;

[0044] During the transportation of the installation tube 6, the pressure in the installation port 2 and the installation tube 6 will increase, and the pressure in the installation port 2 will act on the bottom of the extrusion ring 14 through the connecting hole 22. The extrusion ring 14 will move upward under the action of the pressure inside the installation port 2. When the pressure in the installation port 2 increases, the upward force of the extrusion ring 14 can be increased, thereby ensuring that the extrusion ring 14 can quickly clamp the installation tube 6 after the pressure in the installation port 2 increases.

[0045] When the installation tube 6 is moved to the inside of the installation opening 2, the installation tube 6 cannot be moved to the middle position of the installation opening 2. As a further solution of the present invention, a plurality of arc grooves 23 arranged at equal angles are provided on the inner wall surface of the installation opening 2. The inner wall of the arc groove 23 is an inclined surface. Positioning blocks 24 are slidably connected in the plurality of arc grooves 23. A through hole 25 is provided on the surface of the positioning block 24. The through hole 25 is located below the position of the connecting hole 22.

[0046] When the mounting tube 6 is moved into the mounting opening 2, the mounting tube 6 will move between a plurality of positioning blocks 24. The plurality of positioning blocks 24 can place the mounting tube 6 in the middle position in the mounting opening 2, and the positioning blocks 24 can keep the mounting tube 6 stable. In the subsequent use of the mounting tube 6, when the pressure in the mounting opening 2 increases, the liquid in the mounting tube 6 will act on the positioning blocks 24 to move upward in the arc groove 23. The upward movement of the positioning blocks 24 will move toward the side close to the mounting tube 6 under the action of the arc groove 23, and the mounting tube 6 can be squeezed and clamped, so that the mounting tube 6 can remain stable during transportation, thereby reducing the vibration of the mounting tube 6 during operation.

[0047] During the transportation of the installation tube 6, the extrusion ring 14 will move upward and clamp the installation tube 6 under the action of the sliding groove 13. The annular extrusion ring 14 moves slightly inward under the action of the sliding groove 13, and it is difficult to clamp the installation tube 6 well. As a further solution of the present invention, a plurality of extrusion notches 26 arranged at equal angles are provided on the upper end surface of the extrusion ring 14, and the bottom of the installation tube 6 is an inclined surface;

[0048] During the transportation of the installation tube 6, the extrusion ring 14 will move upward under the action of the pressure in the installation port 2, and the upper end of the extrusion ring 14 will clamp the installation tube 6 under the action of the sliding groove 13. The extrusion groove 26 can provide space for the upper end of the extrusion ring 14 to move inward for clamping, thereby enabling the upper end of the extrusion ring 14 to stably clamp the installation tube 6.

[0049] When the installation tube 6 is moved into the installation opening 2, the installation tube 6 will move the positioning strip 16, and the positioning strip 16 is difficult to move into the positioning groove 15. As a further solution of the present invention, a clearance groove 27 is provided on the inner wall of the sliding groove 13 away from the installation opening 2.

[0050] When the mounting tube 6 is moved to the inside of the mounting opening 2, the mounting tube 6 will squeeze the positioning strip 16, and the upper end of the extrusion ring 14 will move along with it. The upper end of the extrusion ring 14 will be squeezed to move into the yield groove 27, and then when the positioning strip 16 moves into the positioning groove 15, the extrusion ring 14 returns to its original position, which is conducive to the upper end of the extrusion ring 14 moving outward, facilitating the positioning strip 16 to move into the positioning groove 15, thereby ensuring the installation of the mounting tube 6.

[0051] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical ideas disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. An ultra-high pressure metal sealing casing head with a self-locking function, comprising a casing body (1), wherein the casing body (1) is provided with an installation port (2), a flat valve (3), a pressure gauge (4), a sealing groove (5) and a mounting pipe (6), characterized in that: A limiting mechanism is provided on the surface of the sleeve body (1), and the limiting mechanism is used to limit the position of the installation tube (6). A sealing mechanism is provided on the surface of the installation tube (6), and the sealing mechanism is used to seal between the installation tube (6) and the sleeve body (1). An automatic clamping mechanism is provided inside the sleeve body (1), and the automatic clamping mechanism is used to automatically clamp the installation tube (6) when the internal pressure of the sleeve body (1) increases during transportation after the installation of the installation tube (6). A positioning mechanism is provided on the surface of the automatic clamping mechanism, and the positioning mechanism is used to limit the position of the automatic clamping mechanism and the installation tube (6). A fastening mechanism is provided between the automatic clamping mechanism and the limiting mechanism, and the fastening mechanism is used to fasten the limiting mechanism when the automatic clamping mechanism clamps the installation tube (6).

2. The ultra-high pressure metal sealing casing head with self-locking function according to claim 1, characterized in that: The limiting mechanism comprises an annular limiting groove (7), the limiting groove (7) being provided on the surface of the mounting tube (6), a plurality of threaded holes (8) being provided on the surface of the sleeve body (1), a push rod (9) being threadedly connected in each of the plurality of threaded holes (8), and an end of the push rod (9) being located in the limiting groove (7).

3. The ultra-high pressure metal sealing casing head with self-locking function according to claim 2, characterized in that: The sealing mechanism comprises an annular fixing strip (10), wherein the fixing strip (10) is fixedly connected to the surface of the mounting tube (6); two annular grooves (11) are provided on the surface of the fixing strip (10), and a sealing ring (12) is provided in the annular groove (11).

4. The ultra-high pressure metal sealing casing head with self-locking function according to claim 3, characterized in that: The automatic clamping mechanism comprises an annular sliding groove (13), the sliding groove (13) is arranged on the inner wall surface of the installation opening (2), the top of the sliding groove (13) is an inclined surface, an extrusion ring (14) is slidably connected in the sliding groove (13), the upper end of the extrusion ring (14) is an inclined surface, and the sealing ring (12) is in contact with the inner side of the extrusion ring (14).

5. The ultra-high pressure metal sealing casing head with self-locking function according to claim 4, characterized in that: The positioning mechanism comprises an annular positioning groove (15), the positioning groove (15) is formed on the surface of the mounting tube (6), a positioning strip (16) is fixedly connected to the inner surface of the extrusion ring (14), and the upper end of the positioning strip (16) is an inclined surface.

6. The ultra-high pressure metal sealing casing head with self-locking function according to claim 4, characterized in that: The fastening mechanism comprises a plurality of expanded holes (17), wherein the plurality of expanded holes (17) are respectively arranged on the inner side of the threaded hole (8) close to the mounting opening (2), a fastening block (18) is elastically slidably connected in the expanded hole (17), and the fastening block (18) is tapered on the side away from the mounting opening (2), the push rod (9) passes through the fastening block (18) and is threadedly connected to the fastening block (18), an extension groove (19) is arranged at the bottom of the inner wall of the expanded hole (17), the extension groove (19) extends downwardly and communicates with the sliding groove (13), a fastening plate (20) is elastically slidably connected in the extension groove (19), the upper end of the fastening plate (20) is arc-shaped, and the upper end of the fastening plate (20) is in contact with the inclined surface of the end of the fastening block (18), and a retractable pushing block (21) is fixedly connected to the surface of the extrusion ring (14), and the pushing block (21) is located below the fastening plate (20).

7. The ultra-high pressure metal sealing casing head with self-locking function according to claim 4, characterized in that: A plurality of obliquely arranged communication holes (22) are provided at the bottom of the sliding groove (13), and the communication holes (22) are communicated with the installation opening (2).

8. The ultra-high pressure metal sealing casing head with self-locking function according to claim 7, characterized in that: The inner wall surface of the installation opening (2) is provided with a plurality of arc grooves (23) arranged at equal angles, the inner wall of the arc groove (23) is an inclined surface, a positioning block (24) is slidably connected in the plurality of arc grooves (23), a through opening (25) is provided on the surface of the positioning block (24), and the through opening (25) is located below the position of the connecting hole (22).

9. The ultra-high pressure metal sealing casing head with self-locking function according to claim 4, characterized in that: The upper end surface of the extrusion ring (14) is provided with a plurality of extrusion notches (26) arranged at equal angles, and the bottom of the mounting tube (6) is an inclined surface.

10. The ultra-high pressure metal sealing casing head with self-locking function according to claim 4, characterized in that: A clearance groove (27) is formed on the inner wall of the sliding groove (13) at a side away from the installation opening (2).

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