Multifunctional tubing head

Abstract

The invention discloses a multifunctional tubing head, and belongs to the technical field of oil production engineering. A first flange and a second flange are arranged on the wall surface of the traditional tubing head; a first open hole and a second open hole are oppositely formed in the traditional tubing head and used for passing of a tubing cable; the first opening and the second opening are connected with a matched connector in a matched mode in the working process. The multifunctional tubing head selects the matched connector according to the use condition, the requirement that a plurality of underground tubing cables penetrate through a wellhead at the same time under various production working conditions is met, the construction difficulty when the underground tubing cables penetrate through the wellhead is reduced, operation is easier, more convenient and faster, and the operation risk is further reduced. Meanwhile, high-level pressure testing can be carried out (the pressure testing requirement for the pressure level of 70 MPa or above is met), the well mouth sealing capacity is greatly improved, and the production safety is greatly improved for an oil and gas well mouth where underground pipe cables penetrate through.

Description

Technical Field

[0001] The invention belongs to the technical field of oil production engineering and relates to a multifunctional oil tubing head. Background Art

[0002] During the development of oil and gas fields, there are various working conditions that require downhole pipes and cables to be lowered into the well from the casing annulus, such as the following situations: ① If electric pumps are used for production, cables need to be lowered to power the downhole motor; ② If the production string is equipped with a downhole safety valve, a control pipeline needs to be lowered to enable the ground system to control the downhole safety valve; ③ If the oil well has problems such as wax deposition and scaling, a dosing pipeline needs to be lowered to achieve the downhole dosing function; ④ If the oil and gas well uses fiber optic monitoring technology, the optical fiber needs to be lowered into the well along with the production string. The above four working conditions all face the problem of downhole pipes and cables crossing the wellhead, and for a specific single well, there may be a need for multiple pipes and cables to cross the wellhead at the same time. After investigation, there are currently three ways for downhole pipes and cables to cross the wellhead. The specific crossing methods and existing problems are as follows:

[0003] The first is to use a traditional tubing head, such as Figure 1 As shown, there are two methods for passing downhole cables through the wellhead: 1. Conventional cable crossing, where the cable first passes through the tubing hanger and then exits through the upper cover flange of the tubing head. This method requires three seals: two seals between the cable and the tubing hanger, above and below, and one seal between the cable and the upper flange of the cover flange. In actual field operations, this method presents challenges such as multiple steps, long wellhead installation time, high labor intensity, low pressure test level (10 MPa), and susceptibility to cable breakdown. 2. Casing gate crossing, where the cable exits directly through the casing gate. This method requires wire hooking from the casing gate during field operations, making it difficult to construct and presenting safety risks. It also compromises the integrity of the wellhead assembly, preventing pressure testing. Once the cable is exited, the casing gate becomes unusable, and there is a risk of the cable being sheared due to accidental closure of the gate. When a downhole pipeline passes through the wellhead, it typically exits through the downhole safety valve through-hole on the side of the tubing head flange. This is difficult to operate for rigid pipelines, and pressure testing is impossible after the passage. Furthermore, this tubing head cannot meet the requirements for simultaneous passage of downhole pipes and cables under multiple operating conditions.

[0004] The second type is to use traditional tubing head + side opening heightened short section, such as Figure 2As shown, see "high pressure sealing joint design and application" (maintenance and improvement journal, 2009, the 6th issue of the 36th volume, page 76-77). The device is designed with a short section under the lower part of the conventional tubing head, when the downhole cable passes through the wellhead, the downhole cable directly from the side opening of the short section of the height, the operation is simple and retains the integrity of the wellhead device. However, the device is only suitable for electric pump well, not meet the needs of other working conditions pipeline crossing, and increase the height of the wellhead device and increase the difficulty of the construction of the wellhead, but also exist the problem of unable to test pressure.

[0005] The third is to adopt lateral horizontal opening type tubing head, such as Figure 3 As shown, see "new electric pump well tubing head and sealing device" (patent number ZL201220541941.2). The device is improved on the basis of the conventional tubing head, that is, a hole is made in the middle of the conventional tubing head, and the cable directly passes out of the hole when the downhole cable passes through the wellhead. The device is only suitable for electric pump well, and cannot meet the needs of other working conditions of downhole pipeline crossing. Moreover, the cable needs to be bent 90° when crossing, which has the problem of difficult operation. At the same time, the device directly acts on the cable when testing pressure, which can easily damage the outer rubber of the cable and cannot meet the demand of high sealing pressure. SUMMARY

[0006] The purpose of the present application is to solve the technical problems of the prior art that the downhole cable passes through the tubing head into the downhole, which has the problems of difficult operation, multiple processes and unable to test pressure, and provides a multifunctional tubing head.

[0007] In order to achieve the above purpose, the technical scheme is adopted as follows:

[0008] In the first aspect, the present application provides a multifunctional tubing head, which comprises a conventional tubing head provided with a first flange and a second flange on the wall surface; the conventional tubing head is provided with a first opening and a second opening opposite to each other, for the cable to pass through.

[0009] The further improvement of the present application is:

[0010] The connecting line of the relative cross sections of the first opening and the second opening is perpendicular to the connecting line of the first flange and the second flange.

[0011] The opening direction of the first opening and the second opening forms an angle with the wall surface of the conventional tubing head, so that the bending angle of the cable passing through the first opening or the second opening is obtuse.

[0012] The first opening and the second opening are connected with a matching connector when working; the end surface of the first opening and the second opening is provided with a plurality of threaded holes, which are used for connecting the connecting piece to be fixedly connected with the matching connector.

[0013] The end faces of the first opening and the second opening are provided with end face sealing grooves, and the end face sealing grooves are provided with sealing devices.

[0014] The sealing device is a sealing steel ring.

[0015] The connection part of the matched connector and the conventional tubing head is provided with a sealing ring; the matched connector comprises a cable special flange connector, a pipeline special flange connector and a blind plug flange connector.

[0016] The wall surface between the end face of the cable special flange connector, the pipeline special flange connector and the blind plug flange connector and the sealing ring is provided with a pressure test hole.

[0017] The outer wall surface of the cable special flange connector, the pipeline special flange connector and the blind plug flange connector is provided with a dismounting and carrying handle hole.

[0018] The pipeline special flange connector is provided with a plurality of pipeline penetrating holes, and the two ends of the pipeline penetrating holes are NPT sealed.

[0019] Compared with the prior art, the present application has the following beneficial effects:

[0020] The present application discloses a multifunctional tubing head, which directly sets a first opening and a second opening on a conventional tubing head, is simple to operate, does not damage the wellhead integrity, meets the demand of multiple downhole pipes and cables passing through the wellhead at the same time, reduces the construction difficulty when the downhole pipes and cables pass through the wellhead, is simple and convenient to operate, and reduces the operation risk.

[0021] Further, the first opening and the second opening opened on the conventional tubing head have an included angle with the wall surface of the conventional tubing head, so that the bending angle of the pipes and cables passing through the first opening or the second opening is obtuse, the operation is simple during construction, and the risk of damage of the pipes and cables due to the excessively large bending angle is reduced.

[0022] Further, the multifunctional tubing head selects a matched connector according to the use condition, the matched connector comprises a cable special flange connector, a pipeline special flange connector and a blind plug flange connector, meets the demand of multiple downhole pipes and cables passing through the wellhead at the same time under various production conditions, reduces the construction difficulty when the downhole pipes and cables pass through the wellhead, is more simple and convenient to operate, and further reduces the operation risk.

[0023] Further, the end face of the matched connector is provided with a steel ring sealing, the connection part of the wall surface of the matched connector and the conventional tubing head is provided with a sealing ring, the wall surface between the end face of the matched connector and the sealing ring is provided with a pressure test hole, high-level pressure test (satisfying the pressure test demand of 70 MPa and above) can be performed, the sealing capacity of the wellhead is greatly improved, and the production safety of the wellhead of the oil and gas well with the downhole pipe and cable passing through is greatly improved. BRIEF DESCRIPTION OF DRAWINGS

[0024] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments. It should be understood that the following drawings only show some of the embodiments of the present application, and therefore should not be considered as a limitation to the scope. For those skilled in the art, other related drawings can also be obtained without creative labor.

[0025] Figure 1 is a structural schematic diagram of a traditional tubing head;

[0026] Figure 2 is a structural schematic diagram of a traditional tubing head + lateral opening type heightening nipple;

[0027] Figure 3 is a structural schematic diagram of a lateral horizontal opening type tubing head;

[0028] Figure 4 is a structural schematic diagram of a multifunctional tubing head and blind plug flange joint in the present application;

[0029] Figure 5 is a structural schematic diagram of a multifunctional tubing head and pipe / cable special flange joint in the present application;

[0030] Figure 6 is a connection schematic diagram of a multifunctional tubing head and wellhead flange in the present application.

[0031] Among them: 1 - traditional tubing head; 2 - first flange; 3 - second flange; 201 - coupling ground terminal box; 202 - high pressure sealing joint; 203 - clamp; 204 - joint; 205 - coupling downhole power cable; 206 - heightening nipple; 4 - multifunctional tubing head; 5 - threaded hole; 6 - steel ring groove; 7 - pressure test hole; 8 - pressure test gap; 9 - dismounting and carrying handle hole; 10 - cable special flange joint; 11 - pipeline special flange joint; 12 - pipeline crossing hole; 13 - NPT sealing structure; 14 - blind plug flange joint; 15 - sealing groove; 16 - tubing hanger. DETAILED DESCRIPTION

[0032] In order to make the purpose, technical solutions and advantages of the embodiments of the present application more clear, the following will combine the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are some of the embodiments of the present application, not all of the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0033] Therefore, the following detailed description of the embodiments of the application provided in the accompanying drawings is not intended to limit the scope of the application claimed, but merely represents selected embodiments of the application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the application, without making creative efforts, fall within the scope of the application.

[0034] It should be noted that similar reference numbers and letters represent similar items in the following drawings, and therefore, once an item is defined in one drawing, it need not be further defined and explained in subsequent drawings.

[0035] In the description of the embodiments of the application, it should be noted that if the terms "upper", "lower", "horizontal", "inner", and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the application is usually placed, and are merely for the convenience of describing the application and simplifying the description, and therefore, cannot be understood as indicating or implying that the device or element must have a particular orientation, be constructed and operated in a particular orientation, and therefore, cannot be understood as limiting the application. In addition, the terms "first", "second", and the like are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0036] In addition, if the term "horizontal" appears, it does not mean that the component must be absolutely horizontal, but can be slightly inclined. For example, "horizontal" only means that its direction is relatively more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly inclined.

[0037] In the description of the embodiments of the application, it should also be noted that unless otherwise explicitly specified and limited, if the terms "arrangement", "installation", "connection", "connection" appear, they should be understood in a broad sense, for example, they can be fixedly connected, or detachably connected, or integrally connected; can be mechanically connected, or electrically connected; can be directly connected, or indirectly connected through an intermediate medium, or the communication between two elements inside. For those of ordinary skill in the art, the specific meaning of the above terms in the application can be understood according to the specific circumstances.

[0038] The application will be described in further detail below with reference to the accompanying drawings:

[0039] Reference is made to Figure 4 and Figure 5The embodiment of the present application discloses a multifunctional tubing head, comprising a conventional tubing head 1 provided with a first flange 2 and a second flange 3 on a wall surface; the conventional tubing head 1 is oppositely provided with a first opening and a second opening, thereby becoming a multifunctional tubing head 4 for cable passing; the first opening and the second opening are connected with a matched connector in cooperation in working. The opening direction of the first opening and the second opening and the wall surface of the conventional tubing head 1 all have an included angle, so that the bending angle of the cable passing through the first opening or the second opening is an obtuse angle. The end surface of the first opening and the second opening is provided with a plurality of threaded holes 5, which are used for connecting the connecting member to be fixedly connected with the matched connector, thereby realizing the connection of the multifunctional tubing head 4 with a cable special flange connector 10, a pipeline special flange connector 11 or a blind plug flange connector 14. The end surface of the first opening and the second opening is provided with an end surface sealing groove, which is a steel ring groove, and a sealing steel ring is arranged in the end surface sealing groove, thereby realizing the steel ring sealing of the multifunctional tubing head 4 with the cable special flange connector 10, the pipeline special flange connector 11 or the blind plug flange connector 14.

[0040] The matched connector is provided with a rubber sealing ring at the connection position of the matched connector and the conventional tubing head 1; the matched connector comprises the cable special flange connector 10, the pipeline special flange connector 11 and the blind plug flange connector 14. The wall surface of the cable special flange connector 10, the pipeline special flange connector 11 and the blind plug flange connector 14 between the end surface and the sealing ring is provided with a pressure test hole 7, so that the annular gap 8 of the sealing steel ring and the rubber sealing ring can be pressure tested, thereby ensuring that the multifunctional tubing head 4 and each flange connector are effectively sealed, and the pressure test pressure level is greatly improved (more than 70 MPa). The outer wall surface of the cable special flange connector 10, the pipeline special flange connector 11 and the blind plug flange connector 14 is provided with a dismounting and carrying handle hole 9, thereby facilitating carrying and installation. The pipeline special flange connector 11 is provided with one, two or three pipeline through holes 12, and the two ends of the pipeline through hole 12 are NPT sealing.

[0041] The multifunctional tubing head 4 selects the cable special flange connector 10, the pipeline special flange connector 11 or the blind plug flange connector 14 according to different working conditions, so that the downhole cable wellhead passing requirement under multiple working conditions can be met, and the construction difficulty and labor intensity of the downhole cable passing wellhead can be reduced. The new multifunctional tubing head is used in cooperation with the blind plug flange connector 14, so that the integrity and safety of the wellhead when the downhole cable does not pass through the wellhead can be ensured.

[0042] Referring to Figure 6 The connecting line of the relative cross sections of the first opening and the second opening is perpendicular to the connecting line of the first flange 2 and the second flange 3.

[0043] Referring to Figure 5, the cable special flange joint 10 can be connected and sealed with the multifunctional tubing head 4. The internal cable of the cable special flange joint 10 can be directly connected with the downhole cable and the surface cable. After the cable special flange joint 10 is connected with the multifunctional tubing head 4, two seals are formed (the metal ring seal between the flange end face and the opening end face of the multifunctional tubing head, and the rubber seal between the two O-rings in the front section of the flange joint and the opening inside the multifunctional tubing head). A pressure test hole 7 is designed on the side end face of the cable special flange joint 10. After the cable special flange joint 10 is connected with the multifunctional tubing head 4, the pressure test hole 7 can test the pressure test gap 8 between the two seals to ensure that the multifunctional tubing head 4 and the cable special flange joint 10 are effectively sealed and the pressure test level is greatly improved (above 70 MPa). At the same time, a dismounting and carrying handle hole 9 is designed on the side end face of the cable special flange joint 10 to facilitate the carrying and installation of the cable special flange joint 10.

[0044] The pipeline special flange joint 11 can be connected and sealed with the multifunctional tubing head 4. Specifically, pipeline through holes 12 are designed on the flange face of the pipeline special flange joint 11, and the number of pipeline through holes is 1, 2 or 3. After the downhole pipeline passes through the flange joint, the two ends are sealed by NPT sealing structure 13. The sealing and pressure test between the multifunctional tubing head 4 and the pipeline special flange joint 11 are the same as those of the cable special flange joint 10, which can ensure that the multifunctional tubing head 4 and the pipeline special flange joint 11 are effectively sealed and the pressure test level is greatly improved (above 70 MPa). Different numbers of through hole flange joints can meet the needs of single pipeline or multiple pipeline passing through, such as downhole dosing pipeline, safety valve pipeline and optical fiber test pipeline, and realize the simultaneous passing through of multiple downhole pipelines under various complex working conditions.

[0045] Referring to Figure 4 The flange face of the blind plug flange joint 14 has no opening, and the sealing and pressure test between the multifunctional tubing head 4 and the blind plug flange joint 14 are the same as those of the cable special flange joint 10, which can ensure that the multifunctional tubing head 4 and the blind plug flange joint 14 are effectively sealed and the pressure test level is greatly improved (up to 70 MPa). When there is no cable or pipeline passing through, the installation of the blind plug flange joint 14 ensures the safety of the tubing head.

[0046] The multifunctional tubing head selects a matching joint according to the use condition to meet the demand of simultaneous passing through of multiple downhole pipelines at the wellhead under various production conditions, reduces the construction difficulty of downhole pipeline passing through the wellhead, and is more convenient and fast to operate, further reducing the operation risk. The end face of the matching joint is provided with a ring seal, the wall surface is provided with a sealing ring at the connection with the traditional tubing head, and the wall surface between the end face of the matching joint and the sealing ring is provided with a pressure test hole for high-level pressure test (satisfying the pressure test requirement of 70 MPa and above), greatly improving the sealing capacity of the wellhead. For the wellhead of an oil and gas well with downhole pipeline passing through, the production safety is greatly improved.

[0047] The above merely provides the preferred embodiments of the present application, and is not intended to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall fall within the scope of protection of the present application.

Claims

1. A multi-functional tubing head, characterized by, The utility model provides a traditional tubing head (1) which comprises a first flange (2) and a second flange (3) arranged on the wall surface; a first opening and a second opening are oppositely arranged on the traditional tubing head (1) for the passage of a pipe cable.

2. The multi-functional tubing head of claim 1, wherein, The connecting line of the opposite cross sections of the first opening and the second opening is perpendicular to the connecting line of the first flange (2) and the second flange (3).

3. The multi-functional tubing head of claim 1, wherein, The first opening and the second opening are both arranged at an angle with the wall surface of the traditional tubing head (1), so that the bending angle of the pipe cable passing through the first opening or the second opening is obtuse.

4. The multi-functional tubing head of claim 1, wherein, The first opening and the second opening are connected with a matching connector during operation; a plurality of threaded holes (5) are arranged on the end surface of the first opening and the second opening for the connection of a connecting member with the matching connector.

5. The multi-functional tubing head of claim 1, wherein, An end surface sealing groove is arranged on the end surface of the first opening and the second opening, and a sealing device is arranged in the end surface sealing groove.

6. The multi-functional tubing head of claim 5, wherein, The sealing device is a sealing steel ring.

7. The multi-functional tubing head of claim 5, wherein, A sealing ring is arranged at the connection between the matching connector and the traditional tubing head (1); the matching connector comprises a cable special flange connector (10), a pipeline special flange connector (11) and a blind plug flange connector (14).

8. The multi-functional tubing head of claim 7, wherein, A pressure test hole (7) is arranged on the wall surface between the end surface of the cable special flange connector (10), the pipeline special flange connector (11) and the blind plug flange connector (14) and the sealing ring.

9. The multi-functional tubing head of claim 7, wherein, A dismounting and carrying handle hole (9) is arranged on the outer wall surface of the cable special flange connector (10), the pipeline special flange connector (11) and the blind plug flange connector (14).

10. The multi-functional tubing head of claim 7, wherein, A plurality of pipeline through holes (12) are arranged on the pipeline special flange connector (11), and the two ends of the pipeline through holes (12) are both NPT sealed.

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