CN115749665A - Hanger neck high-pressure metal seal combination in extreme environment - Google Patents
Hanger neck high-pressure metal seal combination in extreme environment Download PDFInfo
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- CN115749665A CN115749665A CN202211607451.2A CN202211607451A CN115749665A CN 115749665 A CN115749665 A CN 115749665A CN 202211607451 A CN202211607451 A CN 202211607451A CN 115749665 A CN115749665 A CN 115749665A
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Abstract
The invention discloses a high-pressure metal sealing combination for a hanger neck in an extreme environment, which comprises a hanger body, the hanger neck, a four-way connecting part, an upper pressing ring, a metal sealing ring, a lower pressing ring and a bolt, wherein the hanger body and the hanger neck are integrally formed, the sealing combination part is positioned at the position of the hanger neck on the hanger body in a sealing mode, and the upper pressing ring, the metal sealing ring and the lower pressing ring are sequentially arranged on the sealing combination part. According to the hanger neck high-pressure metal seal combination in the extreme environment, the reliability of sealing under the condition that the highest pressure is 20000PSI (namely 140 Mpa) can be met through the improved high-pressure metal seal design, the problem that excitation operation is needed after the neck seal is installed in the traditional sense is avoided, the field operation time is shortened, the efficiency is improved, the cost is reduced, and sealing can be realized by one-time entering.
Description
Technical Field
The invention relates to the field of oil exploitation equipment, in particular to a hanger neck high-pressure metal sealing combination in an extreme environment.
Background
The high-pressure metal seal combination of the hanger neck in the extreme environment is a supporting device for carrying out seal positioning on the hanger neck, in the technical field of API6A, the seal of various components plays a role in lifting the weight of wellhead equipment from beginning to end, the quality of the seal is directly related to the quality of the whole set of wellhead equipment, the hanger is used as an important part for well completion, the sealing performance of the hanger is particularly important, and along with the continuous development of science and technology, the manufacturing process requirements of people on the high-pressure metal seal combination of the hanger neck in the extreme environment are higher and higher.
The high-pressure metal sealing combination of the neck of the existing hanger in the extreme environment has certain disadvantages when in use, at present, because the fracturing operation is popularized in the international and domestic markets, and meanwhile, the pressure of the fracturing operation also tends to increase, the sealing (rubber sealing and metal sealing) of the existing hanger is difficult to meet the requirement of the fracturing operation with higher pressure (20000PSI, 145Mpa), and certain adverse effects are brought to the actual using process. Therefore, the mechanism of seal failure is analyzed by combining the past experience, and the seal structure of the hanger neck is redesigned, so that the seal structure can meet the requirement of the seal of the hanger neck with the highest pressure of 20000PSI (145 MPa), and therefore, a high-pressure metal seal combination for the hanger neck in an extreme environment is provided.
Disclosure of Invention
Technical problem to be solved
Aiming at the defects of the prior art, the invention provides a high-pressure metal seal combination for a neck of a hanger in an extreme environment, and through the improved high-pressure metal seal design, the reliability of sealing under the condition that the highest pressure is 20000PSI (pressure differential oscillator), namely 140Mpa, can be met, and meanwhile, the problem that in the traditional sense, excitation operation is needed after the neck seal is installed is avoided, the field operation time is shortened, the efficiency is improved, the cost is reduced, the sealing can be realized by one-time dropping, and the problems in the background art can be effectively solved.
(II) technical scheme
In order to achieve the purpose, the invention adopts the technical scheme that: the utility model provides a hanger neck high pressure metal seal combination in extreme environment, includes hanger body, hanger neck, cross connecting portion, seal assembly portion, upper portion clamp ring, metal seal ring, lower part clamp ring, hanger support and bolt, on the hanger body with the position integrated into one piece of hanger neck, the position of the hanger neck of seal assembly portion seal location on the hanger body, upper portion clamp ring, metal seal ring and lower part clamp ring set gradually in seal assembly portion, the upper portion clamp ring is located metal seal ring's top surface, the lower part clamp ring is located metal seal ring's bottom surface, cross connecting portion fixes a position at the top position of hanger body.
As a preferred technical scheme of this application, cross connecting portion is for going up flange production tree or upper portion connects one in the cross part, and the surface of cross connecting portion paints grease.
As an optimal technical scheme of this application, set up the backing ring groove on the cross connecting portion, and the inside location of backing ring groove places the sanitization's backing ring.
As an optimal technical scheme, test oil is filled in an annular space between the hanger body and the four-way connecting portion.
As this application a preferred technical scheme, fixing bolt's position on the cross-connection portion, and the bolt on the cross-connection portion is adjusted the screw hole downwards well and is fixed a position, the outer circumference position in cross-connection portion upper end sets up retention structure and fixes a position.
As a preferred technical scheme of this application, carry out sealed location combination between sealed composite portion and upper portion clamp ring, metal seal circle and the lower part clamp ring, and the location installation between sealed composite portion and the hanger body.
As a preferred technical scheme of the application, the method comprises the following installation method steps:
s1: after the hanger is hung in place, removing the BOP;
s2: smearing grease on the neck of the hanger, and installing a lower compression ring, a metal sealing ring and an upper compression ring;
s3: vertically hoisting the upper flange Christmas tree or the upper connecting four-way part by using a crane, respectively cleaning and checking the sealing surfaces, and coating grease on the surfaces on the premise of ensuring no damage, scratches or corrosion;
s4: respectively cleaning and checking an upper end backing ring groove and an upper flange of a four-way joint or under the premise that an upper part connecting the four-way joint lower end backing ring groove is not damaged by collision, scratches or corrosion, coating grease, and then placing the cleaned backing ring in the backing ring groove;
s5: filling test pressure oil in an annular space between the hanger and the four-way joint so as to be beneficial to the subsequent pressure test operation;
s6: aligning the upper flange or the upper connecting cross with a screw hole downwards according to a specified direction, ensuring that a bolt is vertically, horizontally and slowly placed downwards to penetrate through and a nut is screwed on, checking the gap of four sides of the lower end of the loosely hung upper flange, paying attention to the fact that the bolt is symmetrically tightened in place on the premise of ensuring that the gaps are equal, and preventing the metal seal from being damaged due to the fact that a single side is pressed;
s7: a pressing nut on the connecting bolt is tightened by knocking the cross opposite side of the wrench, so that the gaps of the four sides between the connecting surfaces are ensured to be equal;
s8: and respectively symmetrically tightening the retention devices on the outer circumferences of the upper ends of the four-way pipes, wherein the retention devices are required to be stressed uniformly, and the hanger and the neck metal sealing assembly are completely installed.
As a preferred technical scheme of the application, the method comprises the following steps: through the inspection of the sealing effect of the upper flange or the upper part connecting the upper part of the four-way joint on the hanger neck metal sealing assembly, the pressing pressure is 20000PSI (pressure differential) which is 140Mpa, the pressure maintaining time is 15min, and no obvious leakage or leakage less than 500PSI is qualified.
(III) advantageous effects
Compared with the prior art, the invention provides a high-pressure metal sealing combination for a neck of a hanger in an extreme environment, which has the following beneficial effects: according to the high-pressure metal seal combination for the neck of the hanger in the extreme environment, the reliability of sealing under the condition that the highest pressure is 20000PSI (pressure differential oscillator), namely 140Mpa, can be met through the improved high-pressure metal seal design, and meanwhile, the excitation operation is required after the neck seal is installed in the traditional sense, so that the field operation time is reduced, the efficiency is improved, the cost is reduced, and the sealing is really realized by one-time entering;
and because the structural design of sealed adoption longitudinal symmetry formula is aided with elastic material, can realize resilience to a certain extent after dismantling upper flange or upper portion connection cross, easily dismantle the change, hanger neck high pressure metal seal composite structure is simple among the whole extreme environment, convenient operation, and the effect of use is better for traditional mode.
Drawings
Fig. 1 is a schematic view of the overall structure of a high-pressure metal seal assembly for a neck of a hanger in an extreme environment.
Fig. 2 is a schematic structural view of a conventional neck metal seal assembly of a hanger.
In the figure: 1. a hanger body; 2. a hanger neck; 3. a four-way connection part; 4. a seal assembly portion; 5. an upper clamp ring; 6. a metal seal ring; 7. a lower clamp ring; 8. a hanger support; 9. and (4) bolts.
Detailed Description
The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings and the detailed description, but those skilled in the art will understand that the following described embodiments are some, not all, of the embodiments of the present invention, and are only used for illustrating the present invention, and should not be construed as limiting the scope of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention. The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available commercially.
In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.
As shown in fig. 1 and 2, a high-pressure metal seal assembly for a neck of a hanger in an extreme environment, including a hanger body 1, a neck 2 of the hanger, a four-way connection portion 3, a seal assembly portion 4, an upper clamp ring 5, a metal seal ring 6, a lower clamp ring 7, a hanger support 8 and a bolt 9, the hanger body 1 is integrally formed with the neck 2 of the hanger, the seal assembly portion 4 is positioned at the position of the neck 2 of the hanger on the hanger body 1 in a sealing manner, the upper clamp ring 5, the metal seal ring 6 and the lower clamp ring 7 are sequentially arranged on the seal assembly portion 4, the upper clamp ring 5 is positioned on the top surface of the metal seal ring 6, the lower clamp ring 7 is positioned on the bottom surface of the metal seal ring 6, and the four-way connection portion 3 is positioned at the top position of the hanger body 1.
Further, the four-way connecting part 3 is one of an upper flange Christmas tree or an upper connecting four-way part, and grease is smeared on the surface of the four-way connecting part 3.
Furthermore, a gasket ring groove is formed in the four-way connecting portion 3, and a cleaned gasket ring is positioned in the gasket ring groove.
Furthermore, test pressure oil is filled in an annular space between the hanger body 1 and the four-way connecting part 3.
Furthermore, the position of the bolt 9 is fixed on the four-way connecting portion 3, the bolt 9 on the four-way connecting portion 3 is downwards aligned with the screw hole and positioned, and the position of the outer circumference of the upper end of the four-way connecting portion 3 is provided with a fixing structure for positioning.
Furthermore, the sealing combination part 4 is combined with the upper pressing ring 5, the metal sealing ring 6 and the lower pressing ring 7 in a sealing and positioning mode, and the sealing combination part 4 is installed with the hanger body 1 in a positioning mode.
Further, the method comprises the following installation steps:
s1: after the hanger is hung in place, removing the BOP;
s2: smearing grease on the neck of the hanger, and installing a lower compression ring, a metal sealing ring and an upper compression ring;
s3: vertically hoisting the upper flange Christmas tree or the upper connecting four-way part by using a crane, respectively cleaning and checking the sealing surfaces, and coating grease on the surfaces on the premise of ensuring no damage, scratches or corrosion;
s4: respectively cleaning and checking an upper end backing ring groove and an upper flange of a four-way joint or a lower end backing ring groove connected with the upper part of the four-way joint without damage, scratch and corrosion, coating grease, and then placing the cleaned backing ring in the backing ring groove;
s5: filling test pressure oil in an annular space between the hanger and the four-way joint so as to be beneficial to the subsequent pressure test operation;
s6: aligning the upper flange or the upper connecting cross with a screw hole downwards according to a specified direction, ensuring that a bolt is vertically, horizontally and slowly placed downwards to penetrate through and a nut is screwed on, checking the gap of four sides of the lower end of the loosely hung upper flange, paying attention to the fact that the bolt is symmetrically tightened in place on the premise of ensuring that the gaps are equal, and preventing the metal seal from being damaged due to the fact that a single side is pressed;
s7: a pressing nut on the connecting bolt is tightened by knocking the cross opposite side of the wrench, so that the gaps of the four sides between the connecting surfaces are ensured to be equal;
s8: and respectively symmetrically tightening the retention devices on the outer circumferences of the upper ends of the four-way pipes, wherein the retention devices are required to be stressed uniformly, and the hanger and the neck metal sealing assembly are completely installed.
Further, method steps comprising the following tests: through the inspection of the sealing effect of the upper flange or the upper part connecting the upper part of the four-way joint on the hanger neck metal sealing assembly, the pressing pressure is 20000PSI (pressure differential) which is 140Mpa, the pressure maintaining time is 15min, and no obvious leakage or leakage less than 500PSI is qualified.
Comparative example:
fig. 2 is a conventional metal seal, and fig. 1 is a modified design structure of the present patent.
As shown in fig. 2, the metal seal of the neck of the conventional hanger is realized by installing an upper flange and then pressurizing the upper flange through a BOP (blow-off valve) to expand the upper flange from inside to outside, and the metal seal has the following disadvantages that 1. The excitation pressure is usually 200 PSI-500 PSI, the pressure equipment of the BOP on site cannot be accurately controlled, and the seal is easily pressurized to cause seal failure under certain extreme conditions; 2. the pressure testing can be carried out only when the upper flange or the upper connecting cross joint cannot be installed due to the fact that the pressure is required to be pressed through the BOP, and the operation time on the spot is wasted; 3. the field installation is dismantled the maintenance inconvenient, and after the single use, because the adhesion effect between the easy production metal of structural reason can't dismantle and change.
As shown in fig. 1, the present patent is directed to the above several cases, redesigned and optimized, and developed a high pressure metal seal assembly that can achieve sealing only by tightening the upper flange connection bolts.
The working principle is as follows: the invention comprises a hanger body 1, a hanger neck part 2, a four-way connecting part 3, a seal combination part 4, an upper pressing ring 5, a metal sealing ring 6, a lower pressing ring 7, a hanger support 8 and a bolt 9, through the improved high-pressure metal seal design, the reliability of sealing under the condition that the highest pressure is 20000PSI (pressure of 140 Mpa) can be met, meanwhile, the excitation operation is also needed after the neck seal is installed in the traditional sense, the field operation time is reduced, the efficiency is improved, the cost is reduced, the sealing is really realized by one-time dropping, after the hanger is hung in place, a BOP (blow-in preventer) is removed, grease is coated at the hanger neck part, the lower pressing ring, the metal sealing ring and the upper pressing ring are installed, an upper flange Christmas tree or the upper four-way connecting part is vertically hung by a crane, the sealing surfaces are respectively cleaned and checked, coating grease on the surface on the premise of ensuring no damage, scratch and corrosion, respectively cleaning and checking an upper end backing ring groove of a four-way joint, an upper flange or an upper part connecting the four-way joint and a lower end backing ring groove of the four-way joint without damage, scratch and corrosion, after the grease is coated, rightly placing a cleaned backing ring in the backing ring groove, filling test pressure oil in an annular space between a hanger and the four-way joint so as to be beneficial to the later pressure test work, aligning the upper flange or the upper part connecting the four-way joint to a screw hole in a specified direction, ensuring that a bolt is vertically, flatly, straightly and slowly put down and penetrated into the bolt and a nut is screwed up, checking the gaps of four sides of the lower end of the upper flange after being loosened, paying attention to symmetrically tightening the bolt in place on the premise of ensuring that the gaps are equal, preventing the metal seal from being pressed to be damaged, tightening a compression nut on the connecting bolt by knocking the opposite sides of a cross wrench, ensuring that the gaps of the four sides between connecting surfaces are equal, and respectively symmetrically tightening the retention devices on the outer circumferences of the upper ends of the four-way pipes, wherein the retention devices are required to be stressed uniformly, and the hanger and the neck metal sealing assembly are completely installed.
It is noted that, herein, relational terms such as first and second (a, b, etc.) and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising a … …" does not exclude the presence of another identical element in a process, method, article, or apparatus that comprises the element.
The foregoing shows and describes the general principles and broad features of the present invention and advantages thereof. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the invention as claimed.
Claims (8)
1. The utility model provides a hanger neck high pressure metal seal combination among extreme environment, includes hanger body (1), hanger neck (2), cross connecting portion (3), seal combination portion (4), upper portion clamp ring (5), metal seal circle (6), lower part clamp ring (7), hanger support (8) and bolt (9), its characterized in that: the hanger comprises a hanger body (1), and is characterized in that the hanger body is integrally formed with the position of a hanger neck part (2), a seal combination part (4) is used for sealing and positioning the position of the hanger neck part (2) on the hanger body (1), an upper pressing ring (5), a metal sealing ring (6) and a lower pressing ring (7) are sequentially arranged on the seal combination part (4), the upper pressing ring (5) is located on the top surface of the metal sealing ring (6), the lower pressing ring (7) is located on the bottom surface of the metal sealing ring (6), and a four-way connecting part (3) is positioned at the top position of the hanger body (1).
2. The extreme environment hanger neck high pressure metal seal combination of claim 1 wherein: the four-way connecting part (3) is one of an upper flange Christmas tree or an upper connecting four-way part, and grease is smeared on the surface of the four-way connecting part (3).
3. The extreme environment hanger neck high pressure metal seal combination of claim 1 wherein: the four-way connecting part (3) is provided with a backing ring groove, and a cleaned backing ring is positioned in the backing ring groove.
4. The extreme environment hanger neck high pressure metal seal combination of claim 1 wherein: and test pressure oil is filled in an annular space between the hanger body (1) and the four-way connecting part (3).
5. The extreme environment hanger neck high pressure metal seal combination of claim 1 wherein: the position of a bolt (9) is fixed on the four-way connecting portion (3), the bolt (9) on the four-way connecting portion (3) is aligned with the screw hole downwards and is positioned, and a positioning structure is arranged at the outer circumference of the upper end of the four-way connecting portion (3) to position.
6. The extreme environment hanger neck high pressure metal seal combination of claim 1 wherein: and the sealing combination part (4) is in sealing and positioning combination with the upper pressing ring (5), the metal sealing ring (6) and the lower pressing ring (7), and the sealing combination part (4) is positioned and installed with the hanger body (1).
7. The high pressure metal seal assembly for a hanger neck in an extreme environment of claim 1, wherein: the method comprises the following steps of:
s1: after the hanger is hung in place, removing the BOP;
s2: smearing grease on the neck of the hanger, and installing a lower compression ring, a metal sealing ring and an upper compression ring;
s3: vertically hoisting the upper flange Christmas tree or the upper connecting four-way part by using a crane, respectively cleaning and checking the sealing surfaces, and coating grease on the surfaces on the premise of ensuring no damage, scratches or corrosion;
s4: respectively cleaning and checking an upper end backing ring groove and an upper flange of a four-way joint or under the premise that an upper part connecting the four-way joint lower end backing ring groove is not damaged by collision, scratches or corrosion, coating grease, and then placing the cleaned backing ring in the backing ring groove;
s5: filling test pressure oil in an annular space between the hanger and the four-way joint so as to be beneficial to the subsequent pressure test operation;
s6: aligning the upper flange or the upper connecting cross with a screw hole downwards according to a specified direction, ensuring that a bolt is vertically, horizontally and slowly placed downwards to penetrate through and a nut is screwed on, checking the gap of four sides of the lower end of the loosely hung upper flange, paying attention to the fact that the bolt is symmetrically tightened in place on the premise of ensuring that the gaps are equal, and preventing the metal seal from being damaged due to the fact that a single side is pressed;
s7: a pressing nut on the connecting bolt is tightened by knocking the cross opposite side of the wrench, so that the gaps of the four sides between the connecting surfaces are ensured to be equal;
s8: and respectively symmetrically tightening the retention devices on the outer circumferences of the upper ends of the four-way pipes, wherein the retention devices are required to be stressed uniformly, and the hanger and the neck metal sealing assembly are completely installed.
8. The extreme environment hanger neck high pressure metal seal combination of claim 1 wherein: method steps comprising the following tests: through the inspection of the sealing effect of the upper flange or the upper part connecting the upper part of the four-way joint on the hanger neck metal sealing assembly, the pressing pressure is 20000PSI (pressure differential) which is 140Mpa, the pressure maintaining time is 15min, and no obvious leakage or leakage less than 500PSI is qualified.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211607451.2A CN115749665A (en) | 2022-12-14 | 2022-12-14 | Hanger neck high-pressure metal seal combination in extreme environment |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211607451.2A CN115749665A (en) | 2022-12-14 | 2022-12-14 | Hanger neck high-pressure metal seal combination in extreme environment |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN115749665A true CN115749665A (en) | 2023-03-07 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202211607451.2A Pending CN115749665A (en) | 2022-12-14 | 2022-12-14 | Hanger neck high-pressure metal seal combination in extreme environment |
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| Country | Link |
|---|---|
| CN (1) | CN115749665A (en) |
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- 2022-12-14 CN CN202211607451.2A patent/CN115749665A/en active Pending
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