Dual-function high-pressure casing sealing device for casing head and tubing head and high-pressure sealing casing

Abstract

The invention discloses a dual-function high-pressure casing sealing device for a casing head and a tubing head and a high-pressure sealing casing, and relates to the technical field of sealing devices, comprising a sealing unit, wherein the sealing unit comprises a gasket and a sealing ring arranged on the high-pressure casing unit, and a sealing member arranged between the gasket and the sealing ring. The dual-function high-pressure casing sealing device for a casing head and a tubing head and the high-pressure sealing casing are provided between pipelines that need to be sealed, so that a self-seal is formed between the sealing ring itself and the casing, and the sealing grease is combined with the grease injection unit so that the sealing grease pushes the interference fit convex block of the sealing ring to squeeze the casing, so that an external excitation seal is formed between the sealing device and the installed pipeline, so that the sealing performance of the high-pressure casing installed with the sealing device meets the requirements of high-pressure or ultra-high-pressure fluid passing, and solves the technical problem that the existing sealing device cannot be used in a casing head or a tubing head with a high-pressure sealing requirement.

Description

Technical Field

[0001] The invention relates to the technical field of sealing devices, in particular to a dual-function high-pressure casing sealing device for a casing head and an oil pipe head and a high-pressure sealing casing. Background Art

[0002] At present, the most widely known casing sealing devices for casing heads and tubing heads are mainly divided into two types: self-sealing and externally excited.

[0003] The self-sealing casing sealing device utilizes the interference fit between the sealing device and the casing to achieve sealing. The disadvantage of this sealing device is that the sealing size of the sealing device is fixed. When it is necessary to cooperate with a large-sized casing, due to the large tolerance of the casing outer diameter size, the casing may be difficult to install into the casing head or tubing head due to the large interference size between the sealing device and the casing. It is also possible that the interference size between the sealing device and the casing is relatively small, resulting in failure to seal high pressure; the interference between the externally excited casing sealing device itself and the casing is very small, and the sealing grease injected from the outside is required to squeeze the sealing device and form a certain reserve pressure, thereby forming a seal with the casing. The disadvantage of this sealing device is that it cannot be used in a casing head or tubing head with high-pressure sealing requirements, otherwise the excessive external pressure will cause the sealing ring to be squeezed into the gap between the casing and the casing head or tubing head body and be damaged. Summary of the invention

[0004] In view of the problems existing in the above-mentioned existing dual-function high-pressure casing sealing device for casing head and tubing head, a first embodiment of the present invention is proposed.

[0005] Therefore, the present invention provides a dual-function high-pressure casing sealing device for a casing head or a tubing head, the purpose of which is to solve the technical problem that the existing sealing device cannot be used in a casing head or a tubing head with high-pressure sealing requirements, and excessive external pressure will cause the sealing ring to be squeezed into the gap between the casing and the casing head or the tubing head body and be damaged.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions: a dual-function high-pressure casing sealing device for a casing head and an oil pipe head, comprising a sealing unit, including a gasket arranged on the high-pressure casing unit, a sealing ring sleeved on the periphery of the gasket and interference-fitted with the gasket, and a sealing member arranged between the gasket and the sealing ring.

[0007] As a preferred solution of the dual-function high-pressure casing sealing device for casing head and tubing head of the present invention, the sealing member comprises an upper sealing member arranged on the upper surface of the gasket and a lower sealing member arranged on the lower surface of the gasket.

[0008] As a preferred solution of the dual-function high-pressure casing sealing device for a casing head and an oil tubing head of the present invention, the upper sealing member and the lower sealing member have the same structure.

[0009] As a preferred solution of the dual-function high-pressure casing sealing device for casing head and tubing head of the present invention, the upper sealing member includes an upper spring retaining ring arranged on the upper surface of the gasket and an upper "L"-shaped gasket arranged between the upper spring retaining ring and the sealing ring.

[0010] As a preferred solution of the dual-function high-pressure casing sealing device for a casing head and tubing head of the present invention, the lower sealing member includes a lower spring retaining ring arranged on the lower surface of the gasket and a lower "L"-shaped gasket arranged between the lower spring retaining ring and the sealing ring.

[0011] As a preferred solution of the dual-function high-pressure casing sealing device for the casing head and the oil pipe head of the present invention, wherein: the sealing ring is provided with a grease filling groove corresponding to the grease injection channel.

[0012] As a preferred solution of the dual-function high-pressure casing sealing device for the casing head and the oil pipe head of the present invention, wherein: the sealing ring is provided with an interference fit protrusion corresponding to the high-pressure casing unit.

[0013] The beneficial effects of the first embodiment of the present invention are as follows: a dual-function high-pressure casing sealing device for a casing head and a tubing head is provided between pipelines that need to be sealed, and the cooperation between the "L"-shaped gasket and the spring retaining ring provided on the sealing ring is utilized, and in combination with a grease injection unit, the sealing grease pushes the interference fit protrusion of the sealing ring to squeeze the casing, so that the sealing performance formed between the sealing device and the installed pipeline meets the requirements of high-pressure or ultra-high-pressure fluid passing, thereby solving the technical problem that the existing sealing device cannot be used in a casing head or a tubing head with high-pressure sealing requirements, and excessive external pressure will cause the sealing ring to be squeezed into the gap between the casing and the casing head or the tubing head body and be damaged.

[0014] In view of the above problems existing in the existing high-voltage sealing sleeve, a second embodiment of the present invention is proposed.

[0015] Therefore, the present invention provides a sealing sleeve with a dual-function high-pressure sleeve sealing device for a sleeve head and a tubing head, the purpose of which is to solve the technical problem that when the sealing device of the existing high-pressure sleeve is subjected to excessive external pressure, the sealing ring will be squeezed into the gap between the sleeve and the sleeve head or the tubing head body and damaged.

[0016] To solve the above technical problems, the present invention provides the following technical solutions: a high-pressure sealing casing equipped with the above-mentioned dual-function high-pressure casing sealing device for casing head and oil pipe head, comprising a high-pressure casing unit, a casing provided with the sealing unit, and a pipe head provided on the casing.

[0017] As a preferred solution of the dual-function high-pressure sealing sleeve of the present invention, a connecting bolt is provided between the sleeve and the pipe head.

[0018] As a preferred solution of the dual-function high-pressure sealing sleeve of the present invention, it also includes a grease injection unit, which includes an injection nozzle corresponding to the injection hole on the pipe head and a grease injection channel arranged on the injection nozzle.

[0019] The beneficial effect of the second embodiment of the present invention is as follows: a dual-function high-pressure casing sealing device for a casing head and a tubing head is provided between the casing and the tube head, and the cooperation between the "L"-shaped gasket and the spring retaining ring provided on the sealing ring is utilized, and a grease injection unit is combined to make the sealing grease push the interference fit protrusion of the sealing ring to squeeze the casing, so that the sealing performance formed between the sealing device, the casing and the tube head can meet the requirements of the passage of high-pressure or ultra-high-pressure fluid, thereby solving the technical problem that when the sealing device matching the existing high-pressure casing is subjected to excessive external pressure, the sealing ring will be squeezed into the gap between the casing and the casing head or the tubing head body and damaged. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0021] Figure 1 It is a schematic diagram of the overall structure of the dual-function high-pressure casing sealing device for the casing head and tubing head of the present invention.

[0022] Figure 2 for Figure 1 Enlarged schematic diagram at point A in the middle.

[0023] Figure 3 It is a structural schematic diagram of a dual-function high-pressure casing sealing device for a casing head and an oil tubing head of the present invention.

[0024] Figure 4 for Figure 3 Enlarged schematic diagram of point B in the middle.

[0025] Figure 5 It is a front view of the high-pressure sealing sleeve of the present invention.

[0026] Figure 6 It is a cross-sectional view of the high-pressure sealing sleeve of the present invention.

[0027] Figure 7 for Figure 6 A partial enlarged view of the maximum interference fit achieved at point C in the middle.

[0028] Figure 8 for Figure 6 A partial enlarged view of the initial interference fit at point C in the middle.

[0029] Fig. 9 for Figure 6 A partial enlarged view of the interference fit after external excitation at point C in the middle.

[0030] Description of the drawings: 100, sealing unit; 101, gasket; 102, sealing ring; 102a, grease filling groove; 102b, interference fit protrusion; 103, sealing member; 103a, upper sealing member; 103a-1, upper "L"-shaped gasket; 103a-2, upper spring retaining ring; 103b, lower sealing member; 103b-1, lower "L"-shaped gasket; 103b-2, lower spring retaining ring; 200, high-voltage bushing unit; 201, bushing; 202, pipe head; 300, grease injection unit; 301, injection nozzle; 302, grease injection channel. DETAILED DESCRIPTION

[0031] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings.

[0032] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0033] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor is it an embodiment that is mutually exclusive with other embodiments, either individually or selectively.

[0034] Secondly, the present invention is described in detail with reference to the schematic diagram. When describing the embodiments of the present invention in detail, for the sake of convenience, the cross-sectional diagrams showing the device structure will not be partially enlarged according to the general scale, and the schematic diagrams are only examples, which should not limit the scope of protection of the present invention. In addition, in actual production, the three-dimensional dimensions of length, width and depth should be included.

[0035] Example 1, reference Figure 1-Figure 4 and Figure 7-Figure 9 , which is the first embodiment of the present invention, provides a dual-function high-pressure casing sealing device for a casing head and an oil tubing head, including a sealing unit 100.

[0036] The sealing unit 100 includes a gasket 101 disposed on the high-voltage bushing unit 200, a sealing ring 102 sleeved on the outer periphery of the gasket 101 and having an interference fit with the gasket 101, and a sealing member 103 disposed between the gasket 101 and the sealing ring 102. The gasket 101 is sleeved on the bushing 201, and multiple groups of gaskets 101 may be provided according to the sealing requirements of the bushing 201, thereby strengthening the sealing connection between the bushing 201 and the pipe head 202. The sealing ring 102 is located between the casing 201 in the high-pressure casing unit 200 and the pipe head 202 in the high-pressure casing unit 200. The pipe head 202 can be a casing head or an oil pipe head. A self-sealing structure is formed between the sealing ring 102 and the high-pressure casing unit 200, that is, an initial interference fit is formed between the sealing ring 102 and the casing 201. It is possible that in the initial state, the interference fit size between the sealing unit 100 and the casing 201 is relatively small, resulting in failure to achieve a sealed high pressure between the casing 201 and the pipe head 202. If the self-sealing structure of the sealing ring 102 is relied on alone, a maximum interference fit will be formed between the sealing ring 102 and the casing 201. This kind of fit size is large, making it difficult for the casing 201 to be installed inside the pipe head 202. The sealing ring 102 provided in this embodiment forms an externally excited sealing structure of the oil with the cooperation of the grease injection unit 300, that is, an externally excited interference fit is formed between the sealing ring 102 and the casing 201, and the size of this externally excited interference fit is between the initial interference fit size and the maximum interference fit size. While satisfying the convenience of installation between the casing 201 and the pipe head 202, it ensures the high-pressure sealing structure between the pipe head 202 and the casing 201, and meets the high-pressure sealing requirements of the secondary sealing part at the bottom of the casing head or the oil tubing head and the casing fitting.

[0037] Preferably, the sealing ring 102 is configured as a "DS" type sealing ring, which is provided with a grease filling groove 102a corresponding to the grease injection channel 302; the grease filling groove 102a is configured as a semicircular groove on the cross section of the sealing ring 102, and the sealing grease can be filled in the grease filling groove 102a, so that an externally stimulated interference fit is formed between the sealing ring 102 and the sleeve 201.

[0038] Furthermore, the sealing ring 102 is provided with an interference fit protrusion 102b corresponding to the high voltage bushing unit 200, and the interference fit protrusion 102b is in close contact with the bushing 201 to form a self-sealing connection structure.

[0039] During use, the sealing unit 100 is composed of a "DS" type sealing ring 102, a sealing member 103 and a gasket 101. The sealing member 103 includes two "L" type metal gaskets vulcanized and arranged at the upper and lower symmetrical positions of the interference fit protrusion 102b inside the "DS" type sealing ring 102, namely, an upper "L" type gasket 103a-1 and a lower "L" type gasket 103b-1; the vulcanized "DS" type sealing ring 102 is installed in the sealing ring groove on the sleeve 201; a sealing member 103 is installed between the upper part of the interference fit protrusion 102b raised on the inner ring of the "DS" type sealing ring 102 and the sealing ring groove. Install the spring retaining ring 103a-2 so that the cut position of the upper spring retaining ring 103a-2 is consistent with the position of the upper "L"-shaped gasket 103a-1 in the "DS" type sealing ring 102; similarly, install a lower spring retaining ring 103b-2 between the lower part of the interference fit protrusion 102b of the inner ring of the sealing ring 102 and the sealing ring groove so that the cut position of the lower spring retaining ring 103b-2 is consistent with the position of the lower "L"-shaped gasket 103b-1 in the "DS" type sealing ring 102. After the initial installation is completed, the outer dovetail of the "DS" type sealing ring 102 fits with the upper and lower surfaces and the bottom surface of the sealing ring groove of the sleeve 201, so that the "DS" type sealing ring 102 and the sealing ring groove form an initial seal. After the sleeve 201 is installed, if it is necessary to improve the sealing performance of the sealing unit 100 by grease injection, inject sealing grease at the injection nozzle 301 and pressurize it to a certain pressure. At this time, the sealing grease pushes the interference fit protrusion 102b of the "DS" type sealing ring 102 to squeeze the sleeve through the grease injection channel 302. At this time, the sealing performance formed by the sleeve sealing unit 100, the sleeve 201 and the pipe head 202 is sufficient to seal high-pressure or ultra-high-pressure fluids.

[0040] Preferably, when the size of the on-site casing 201 is too large, the interference fit of the "DS" type sealing ring 102 in the sealing unit 100 allows the casing 201 to be smoothly inserted into the bottom boring hole of the pipe head 202, and the interference volume of the sealing ring 102 can effectively fill the sealing ring groove to ensure effective sealing performance against high pressure.

[0041] Furthermore, when the casing size on site is relatively small, the sealing device can first use the interference of the "DS" type sealing ring 102 itself and the dovetail structure at the tail to establish an initial seal with the sealing ring groove, and then stimulate it through external grease injection to ensure the high-pressure sealing performance of the casing sealing unit 100.

[0042] Furthermore, if the sealing ring 102 is slightly scratched by the casing 201 during installation, the "DS" type sealing ring 102 can be squeezed by external grease injection to make up for the gap in the sealing ring 102 caused by the damage, thereby increasing the effectiveness of the installation of the sealing device and saving the installation time of the on-site casing 201, that is, the casing head or the tubing head.

[0043] The dual-function casing sealing unit 100 has a maximum theoretical design pressure resistance value of 138 MPa (20,000 psi) according to the size of the casing 201 .

[0044] The high-voltage bushing sealing unit 100 with dual functions of self-sealing and external excitation provided in this embodiment is simple to install and easy to replace, and can ensure that the bushing can be sealed under high pressure.

[0045] Example 2, reference Figure 1-Figure 9 , which is the second embodiment of the present invention. This embodiment is different from the first embodiment in that the upper sealing member 103a and the lower sealing member 103b have the same structure.

[0046] Compared with Example 1, the upper sealing member 103a further comprises an upper spring retainer 103a-2 disposed on the upper surface of the gasket 101, and an upper "L"-shaped gasket 103a-1 disposed between the upper spring retainer 103a-2 and the sealing ring 102. The upper "L"-shaped gasket 103a-1 is vulcanized and disposed inside the sealing ring 102.

[0047] Further, the lower sealing member 103b includes a lower spring retainer 103b-2 disposed on the lower surface of the gasket 101 and a lower "L"-shaped gasket 103b-1 disposed between the lower spring retainer 103b-2 and the sealing ring 102. The lower "L"-shaped gasket 103b-1 is vulcanized and disposed inside the sealing ring 102.

[0048] Among them, the upper spring retaining ring 103a-2 and the lower spring retaining ring 103b-2 on the sleeve sealing unit 100 are open retaining rings. In order to prevent the sealing ring 102 from being damaged under high pressure, an "L"-shaped gasket is vulcanized at the position corresponding to the opening of the upper spring retaining ring 103a-2 and the lower spring retaining ring 103b-2 inside the "DS" type sealing ring 102, which can effectively protect the "DS" type sealing ring 102 from being damaged under high pressure.

[0049] The remaining structures are the same as those of Example 1.

[0050] Example 3, reference Figure 1-Figure 9 , which is the third embodiment of the present invention, provides a sealing sleeve with a dual-function high-pressure sleeve sealing device for a sleeve head and an oil pipe head, including a high-pressure sleeve unit 200, including a sleeve 201 provided with a sealing unit 100, and a pipe head 202 provided on the sleeve 201.

[0051] Furthermore, a connecting bolt 203 is provided between the sleeve 201 and the pipe head 202. Through the setting of the connecting bolt 203, an external excitation fixed installation connection between the sleeve 201 and the pipe head 202 is realized, which further strengthens the external excitation sealing effect between the sleeve 201 and the pipe head 202 and meets the sealing requirements of the high-pressure high-pressure unit under a high-pressure environment.

[0052] Furthermore, it also includes a grease injection unit 300 , which includes an injection nozzle 301 corresponding to the injection hole on the tube head 202 , and a grease injection channel 302 arranged on the injection nozzle 301 .

[0053] During use, a dual-function high-pressure casing sealing device for a casing head and a tubing head is provided between the casing and the pipe head, a sealing unit 100 is provided, a sealing member 103 provided on a sealing ring 102 is utilized, and on the upper surface of the sealing ring 102, an upper "L"-shaped gasket 103a-1 and an upper spring retaining ring 103a-2 are used for cooperation, and on the lower surface of the sealing ring 102, a lower "L"-shaped gasket 103b-1 and a lower spring retaining ring 103b-2 are used for cooperation, and in combination with a grease injection unit 300, the sealing grease pushes the interference fit protrusion of the sealing ring 102 to squeeze the casing, so that the sealing performance formed between the sealing unit 100 and the casing 201 and the pipe head 202 meets the requirements of the passage of high-pressure or ultra-high-pressure fluids, thereby solving the technical problem that when the sealing device matching the existing high-pressure casing is subjected to excessive external pressure, the sealing ring will be squeezed into the gap between the casing and the casing head or the tubing head body and damaged.

[0054] The remaining structure is the same as that of Example 2.

[0055] It is important to note that the construction and arrangement of the present application shown in a number of different exemplary embodiments are only exemplary. Although only a few embodiments are described in detail in this disclosure, it should be readily understood by those who refer to this disclosure that many modifications are possible (e.g., the size, scale, structure, shape and proportion of various elements, as well as parameter values ​​(e.g., temperature, pressure, etc.), mounting arrangements, use of materials, color, changes in orientation, etc.) without substantially departing from the novel teachings and advantages of the subject matter described in this application. For example, an element shown as integrally formed may be composed of multiple parts or elements, the position of the element may be inverted or otherwise changed, and the nature or number or position of the discrete element may be changed or changed. Therefore, all such modifications are intended to be included within the scope of the present invention. The order or sequence of any process or method steps may be changed or reordered according to an alternative embodiment. In the claims, any "device plus function" clause is intended to cover the structure described herein that performs the function, and is not only structurally equivalent but also equivalent structure. Other substitutions, modifications, changes and omissions may be made in the design, operating conditions and arrangement of the exemplary embodiments without departing from the scope of the present invention. Therefore, the invention is not limited to a specific embodiment, but extends to numerous modifications still falling within the scope of the appended claims.

[0056] Additionally, in order to provide a concise description of exemplary embodiments, all features of an actual embodiment may not be described (ie, those features that are not relevant to the best mode presently contemplated for carrying out the invention or those features that are not relevant to implementing the invention).

[0057] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A dual-function high-pressure casing sealing device for casing head and tubing head, characterized in that: include, A sealing unit (100) comprising: A gasket (101) provided on the high voltage bushing unit (200), It is sleeved on the periphery of the gasket (101), and is interference-fitted with the gasket (101) to form a self-sealing structure, and can cooperate with the grease injection unit (300) to form a sealing ring (102) of an external excitation structure. and a sealing member (103) disposed between the gasket (101) and the sealing ring (102); The sealing member (103) comprises an upper sealing member (103a) arranged on the upper surface of the gasket (101), and a lower sealing member (103b) arranged on the lower surface of the gasket (101); The upper sealing member (103a) and the lower sealing member (103b) have the same structure; The upper sealing member (103a) comprises an upper spring retaining ring (103a-2) arranged on the upper surface of the gasket (101), and an upper "L"-shaped gasket (103a-1) arranged between the upper spring retaining ring (103a-2) and the sealing ring (102); The lower sealing member (103b) comprises a lower spring retaining ring (103b-2) arranged on the lower surface of the gasket (101), and a lower "L"-shaped gasket (103b-1) arranged between the lower spring retaining ring (103b-2) and the sealing ring (102); The sealing ring (102) is provided with a grease filling groove (102a) corresponding to the grease injection channel (302); The sealing ring (102) is provided with an interference fit protrusion (102b) corresponding to the high-voltage bushing unit (200).

2. A high-pressure sealing sleeve based on the dual-function high-pressure sleeve sealing device for a casing head and a tubing head according to claim 1, characterized in that: include, A high-voltage bushing unit (200) comprises a bushing (201) provided with the sealing unit (100), and a pipe head (202) provided on the bushing (201).

3. The high-voltage sealing sleeve according to claim 2, characterized in that: A connecting bolt (203) is provided between the sleeve (201) and the pipe head (202).

4. The high-voltage sealing sleeve according to claim 2 or 3, characterized in that: It also includes a grease injection unit (300), which includes an injection nozzle (301) corresponding to the injection hole on the tube head (202), and a grease injection channel (302) arranged on the injection nozzle (301).

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