High temperature resistant electrically traversing downhole connector

Abstract

The application relates to a high-temperature-resistant electric crossing downhole connector, which comprises an outer shell, an electric contact, a movable ejector rod, an outer balance capsule and an inner balance capsule, the movable ejector rod is arranged in the electric contact and can axially move, an insulating front cover and a tail insulator are arranged at the front and rear ends of the outer shell respectively, the outer balance capsule and the inner balance capsule are arranged between the insulating front cover and the tail insulator and surround the electric contact, a ring-shaped front end pressing plate is arranged in the outer balance capsule, the front end pressing plate is axially supported on the inner wall of the front end of the outer balance capsule, a plurality of support rods are arranged between the outer balance capsule and the inner balance capsule and are spaced in the circumferential direction, and the two ends of the support rods are connected with the front end pressing plate and the tail insulator respectively; assembly gaps are left between the outer diameter surfaces of the front and rear ends of the outer balance capsule and the inner diameter surfaces of the outer shell. The application can improve the long-term working reliability and service life of the connector under non-ideal underwater plug-in and plug-out operations.

Description

Technical Field

[0001] This invention belongs to the field of electrical connector technology, specifically relating to an electrical cross-through connector for underwater environments, and more particularly to a high-temperature resistant electrical cross-through downhole connector suitable for offshore oil and gas wellhead equipment. Background Technology

[0002] In underwater engineering fields such as offshore oil and gas extraction and deep-sea exploration, high-temperature resistant electrical through-hole connectors are key components for power and signal transmission between underwater devices. They are typically installed in critical locations such as tubing hangers at the wellhead and must operate under harsh sea conditions of high temperature and pressure for extended periods. To ensure repeated wet-prone insertion and removal operations in deep-sea environments, a typical type of connector—the pressure-balanced wet-prone connector—is widely used. This type of connector generally employs a multi-stage sealing and pressure-balanced structural design to achieve its core functions.

[0003] A typical pressure-balanced wet-plug connector mainly comprises a housing, an outer balance bladder, an inner balance bladder, a movable push rod, and contacts. Its sealing mechanism is achieved primarily through the following: one end of the outer balance bladder is mounted in a groove in the tail insulator via a protruding structure, while the other end rests against the insulating end cap for positioning. A contact in the middle provides axial positioning to prevent large-scale axial movement. Simultaneously, the outer balance bladder and the movable push rod form the first layer of seal, the main seal. The front end of the inner balance bladder is embedded in a small hole in the insulating end cap to prevent axial and radial displacement, and forms a second layer of seal with the movable push rod. The axial distance between the inner balance bladder and the movable push rod is relatively short. The housing has two O-ring grooves, forming a non-metallic seal with the user's mounting panel.

[0004] However, in actual underwater insertion and removal operations, this structure still has significant reliability risks. When the connector is in an oblique insertion position, or due to deviations in processing and assembly, or under non-ideal conditions such as severe fluctuations in seawater pressure, the outer balancing bladder, which acts as the main seal, is prone to significant axial or radial displacement from its mating surface. This displacement directly leads to the failure of the first layer of seal. Once the main seal fails, high-pressure seawater will quickly intrude and fill the outer balancing bladder cavity. More critically, due to the short axial distance between the inner balancing bladder and the movable push rod, the second layer of seal will quickly lose its sealing ability under conditions of seawater intrusion, oblique insertion, or foreign objects. This will directly cause a sharp decline in insulation performance, ultimately leading to the failure of the entire connector's electrical function, severely shortening its working life and reliability in the subsea environment. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a high-temperature resistant electrical penetration downhole connector. While maintaining its adaptability to high-temperature operating conditions, the sealing structure of the connector is optimized to solve problems such as reduced insulation performance and decreased reliability caused by oblique insertion, foreign objects, or assembly deviations in existing technologies. This improves the long-term reliability and service life of the connector under non-ideal underwater insertion and removal operations.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A high-temperature resistant electrical penetration downhole connector includes a housing and an electrical contact, a movable push rod, an outer balance bladder, and an inner balance bladder disposed within the housing. The movable push rod is axially movable within the electrical contact. Insulating end caps and tail insulators are respectively disposed at the front and rear ends of the housing. The outer and inner balance bladders surround the electrical contact and are disposed between the insulating end caps and tail insulators. An annular front pressure plate is disposed inside the outer balance bladder, and the front pressure plate is axially supported on the inner wall of the front end of the outer balance bladder. Multiple support rods are circumferentially spaced between the outer and inner balance bladders, and the two ends of the support rods are respectively connected to the front pressure plate and the tail insulator. Assembly gaps are left between the outer diameter surfaces of the front and rear ends of the outer balance bladder and the inner diameter surfaces of the housing.

[0007] Its beneficial effects are: by setting the support rod and forming a small gap fit between the front and rear ends of the outer balance bag and the outer shell through the assembly gap, the present invention can prevent the outer balance bag from axially and radially deflecting in a large range when the connector is inserted at a large angle, thereby avoiding the problem of failure of the first seal composed of the outer balance bag and the movable top rod due to excessive deformation of the outer balance bag; in addition, the small gap fit formed by the assembly gap can also facilitate the assembly of the outer balance bag.

[0008] Furthermore, the front end pressure plate is provided with a front positioning hole, the tail end insulator is provided with a rear positioning hole, and the two ends of the support rod are respectively inserted into the front positioning hole and the rear positioning hole.

[0009] Its beneficial effects are: without adding new parts, by modifying the structure of existing parts and adding corresponding positioning holes, the front and rear ends of the support rod can be reliably fixed, thereby ensuring that the support rod can provide reliable support for the external balance bag when the connector is inserted at an angle.

[0010] Furthermore, the end face of the front end of the inner balance bladder contacts the insulating end cap, and the inner diameter surface of the front end of the inner balance bladder is dynamically sealed to the outer circumferential surface of the movable push rod. A non-metallic ring is fitted onto the outer diameter surface of the front end of the inner balance bladder, and the outer diameter surface of the non-metallic ring contacts the inner diameter surface of the front pressure plate.

[0011] Its beneficial effects are: the end face of the inner balance bladder contacts the insulating end cap, which can greatly increase the sealing length between the inner balance bladder and the movable push rod, effectively preventing sealing failure caused by oblique insertion or foreign objects. At the same time, the non-metallic ring at the front end of the inner balance bladder can prevent radial displacement of the inner balance during insertion and removal, ensuring that the movable push rod can rebound smoothly.

[0012] Furthermore, the inner diameter surface of the front end pressure plate is provided with an annular groove to accommodate the non-metallic ring.

[0013] Its beneficial effect is that the ring groove can be radially positioned for non-metallic rings.

[0014] Furthermore, the front end face of the external balancing bladder is provided with multiple protrusions, which are in close contact with the insulating end cap.

[0015] Its beneficial effects are: the raised design can absorb the tolerances generated during product assembly, and it also has the function of buffering and preventing the axial movement of the outer balance bag.

[0016] Furthermore, a protrusion is provided on the outer diameter surface of the front end of the outer balance bladder, and an assembly gap is left between the protrusion and the inner diameter surface of the outer shell.

[0017] Its beneficial effects are: by setting protrusions, a small-area gap fit is achieved between the front end of the outer balance bladder and the outer shell, which can provide space for deformation of the outer balance bladder while radially constraining the front end of the outer balance bladder.

[0018] Furthermore, the rear end of the outer casing is provided with an annular conical surface, and the middle part of the outer casing is provided with a clamping nut.

[0019] Its beneficial effect is that when the connector is connected to the matching mounting housing, during the process of tightening the nut to lock the connector, the conical surface and the mounting housing undergo plastic deformation to form a metal seal.

[0020] Furthermore, the rear end of the outer casing is also fitted with several O-rings, and the O-rings are located in front of the conical surface.

[0021] Its beneficial effects are: when the connector is connected to the matching mounting housing, the O-ring seal forms a non-metallic seal with the mounting housing, which together with the metal seal formed by the conical surface constitutes a double sealing structure, effectively improving the sealing performance and reliability of the product.

[0022] The beneficial effects of this invention are: by making a series of improvements to the fixing structure and sealing design of the connector's inner balance bladder, this invention can avoid the problem of sealing structure failure caused by the axial and radial deviation of the outer or inner balance bladder when the connector is inserted at a large angle, thereby greatly improving the reliability of the connector. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the high-temperature resistant electrical penetration downhole connector described in this invention; Figure 2 This is a schematic diagram of the front end of the sealing structure in the high-temperature resistant electrical penetration downhole connector of the present invention; Figure 3 This is a schematic diagram of the tail end of the high-temperature resistant electrical penetration downhole connector described in this invention; The markings in the diagram are: 1. Insulating end cap, 2. Non-metallic ring, 3. Front pressure plate, 4. Outer balance bladder, 5. Support rod, 6. Inner balance bladder, 7. Tail insulator, 8. Outer shell, 9. Movable top rod, 10. Drain hole, 11. Compression nut, 12. Electrical contact, 13. Ring groove, 14. Front positioning hole, 15. Protrusion, 16. Bump, 17. Conical surface, 18. O-ring seal. Detailed Implementation

[0024] The present invention will be further described in detail below with reference to the embodiments, but this should not be construed as limiting the invention in any way.

[0025] like Figure 1 As shown, the high-temperature resistant electrical penetration downhole connector of the present invention includes a housing 8, an insulating end cap 1 disposed within the housing 8, a front pressure plate 3, an outer balance bladder 4, an inner balance bladder 6, a tail insulator 7, a movable push rod 9, and an electrical contact 12, as well as a clamping nut 11 disposed outside the housing 8. The insulating end cap 1 is annular and located at the connector insertion interface position at the front end of the housing 8. The tail insulator 7 is located at the rear end of the housing 8, and the installation method of the insulating end cap 1 and the tail insulator 7 within the housing 8 is the same as that of the insulating end cap 1 and the tail insulator 7 in existing pressure-balanced wet-plug electrical connectors. The movable push rod 9 is installed in the insertion hole of the electrical contact 12, with the front end of the movable push rod 9 extending out of the insertion hole of the electrical contact 12, and the rear end of the electrical contact 12 installed within the tail insulator 7. The installation method of the movable push rod 9 and the electrical contact 12 is the same as that in existing pressure-balanced wet-plug electrical connectors.

[0026] An inner balancing bladder 6 and an outer balancing bladder 4 are provided between the insulating end cap 1 and the tail insulator 7, surrounding the electrical contact.

[0027] The external medium of the outer balance bladder 4 is seawater. Seawater enters the interior of the housing through the drain hole 10 of the outer housing 8. The outer balance bladder 4 is filled with silicone oil. Without considering the compressibility of the silicone oil, the pressure of the internal silicone oil will be balanced with the external water pressure. By utilizing the expansion and contraction characteristics of the outer balance bladder 4, the volume change during the mating process is adjusted, thereby achieving the balance of the internal and external pressure of the connector.

[0028] The medium that the inner balance bladder 6 contacts externally is the silicone oil in the outer balance bladder 4, and the interior is also filled with silicone oil. By utilizing the expansion and contraction characteristics of the inner balance bladder 6, the volume change during the mating process is adjusted, thereby achieving internal pressure balance and maintaining reliable electrical insulation of the connector during underwater mating and unmating.

[0029] The inner and outer balance bladders are key components of the electrical ride-through connector. Due to the high ambient temperature of the electrical ride-through connector, the material requirements are very high. The materials of the inner and outer balance bladders must be resistant to high temperature environments, have good compatibility with seawater and silicone oil, and have excellent aging resistance. At the same time, they must also have certain tensile and tear resistance properties to allow the balance bladder to contract and expand.

[0030] The outer balance bladder 4 is the primary seal, and the inner balance bladder 6 is the secondary seal, isolating external seawater so that the electrical contact 12 is always in an insulating environment. Therefore, the fixing structure and sealing design of the balance bladder are very critical and directly affect the performance and service life of the product.

[0031] like Figure 1 , 2 As shown, in this invention, an annular front end pressure plate 3 is provided inside the outer balance bladder 4, and is axially supported on the inner wall of the front end of the outer balance bladder 4 to maintain the structural strength of the front end of the outer balance bladder 4. Multiple support rods 5 are arranged circumferentially in the cavity between the outer balance bladder 4 and the inner balance bladder 6. The front end of the support rod 5 is inserted into the front positioning hole 14 of the front end pressure plate 3, and the rear end of the support rod 5 is inserted into the rear positioning hole of the tail insulator 7. In this embodiment, three support rods 5 are provided; in other embodiments, two or more than three support rods 5 may be provided. The support rods 5 provide axial positioning of the outer balance bladder 4, preventing large axial movement of the outer balance bladder 4. An assembly gap is left between the outer diameter surfaces of the front and rear ends of the outer balance bladder 4 and the inner diameter surfaces of the outer shell 8. This facilitates the assembly of the outer balance bladder and provides a small clearance fit, offering a certain radial constraint to the outer balance bladder 4 and preventing large-scale radial deviation when the connector is inserted at a large angle. Furthermore, when the connector is inserted at a large angle, it can avoid large displacement and deflection of the outer balance bladder 4 in the axial and radial directions, ensuring the reliability of the first seal formed by the outer balance bladder 4.

[0032] Furthermore, the front end face of the outer balancing bladder 4 is provided with multiple protrusions 15, which are in close contact with the insulating end cap 1. By providing the protrusions 15, tolerances generated during product assembly can be absorbed, and the protrusions also serve to buffer and prevent axial movement of the outer balancing bladder 4.

[0033] Furthermore, the outer balancing bladder 4 needs to balance the internal and external pressure difference during connector operation, thus requiring it to undergo contraction and expansion deformation. To facilitate this deformation, a protrusion 16 is provided on the outer diameter surface of the front end of the outer balancing bladder 4. This protrusion 16 allows for a small-range fit between the front end of the outer balancing bladder 4 and the outer shell 8, providing radial constraint while maintaining a certain gap between the front end of the outer balancing bladder 4 and the inner diameter surface of the outer shell 8 outside the protrusion 16, thereby providing deformation space for the outer balancing bladder 4. The protrusion 16 is annular.

[0034] In the prior art, the inner balance bladder 6 and the movable push rod 9 are fitted with a rib. In this invention, the front end of the movable push rod 9 passes through the opening of the inner balance bladder 6, and a dynamic seal is formed between the inner wall of the opening and the outer circumferential surface of the movable push rod 9. The movable push rod 9 can slide axially back and forth within the opening. Furthermore, the length of the front end of the inner balance bladder 6 is further increased, allowing the front end face of the inner balance bladder 6 to contact the front insulating end cap 1. This improves the axial positioning effect of the inner balance bladder 6 and prevents large-amplitude axial displacement of the inner balance bladder 6. Furthermore, a non-metallic ring 2 is fitted onto the outer diameter surface of the front end of the inner balance bladder 6. The non-metallic ring 2 is located in the annular groove 13 formed between the front pressure plate 3 and the inner balance bladder 6. The outer diameter surface of the non-metallic ring 2 contacts the inner diameter surface of the front pressure plate 3, and the front pressure plate 3 provides radial support for the non-metallic ring 2, thereby improving the radial support of the inner balance bladder 6. By improving the mounting structure of the inner balance bladder 6, large-scale axial and radial displacement of the inner balance bladder 6 is prevented during the oblique insertion of the connector, thus avoiding the formation of leakage channels.

[0035] The present invention also improves the structure of the outer shell 8, such as... Figure 3 As shown, a conical surface 17 is provided on the outer diameter surface of the rear end of the outer shell 8, which is located in front of the two O-rings 18 on the surface of the outer shell 8. When the connector of the present invention is installed in a suitable mounting housing, it is fixed to the mounting housing by a threaded connection of a clamping nut 11 on the outer shell 8, and a suitable tightening torque is further applied, so that the conical surface 17 acts on the inclined surface inside the mounting housing, thereby causing the conical surface 17 and the inclined surface of the mounting housing to undergo metal plastic deformation, achieving a metal seal. The metal seal serves as the first seal between the connector and the mounting housing, and the non-metallic seal formed between the O-rings 18 on the outer shell 8 and the mounting housing serves as the second seal between the connector and the mounting housing. Through the first and second seals, the reliability of the connector is greatly improved.

[0036] The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Those skilled in the art should understand that modifications or equivalent substitutions can be made to the specific implementation of the present invention with reference to the above embodiments. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention are within the protection scope of the pending claims.

Claims

1. A high-temperature resistant electrical penetration downhole connector, comprising a housing (8) and an electrical contact (12), a movable push rod (9), an outer balance bladder (4), and an inner balance bladder (6) disposed within the housing (8), wherein the movable push rod (9) is axially movable within the electrical contact (12), and an insulating end cap (1) and a tail insulator (7) are respectively disposed at the front and rear ends of the housing (8), the outer balance bladder (4) and the inner balance bladder (6) are disposed around the electrical contact (12) between the insulating end cap (1) and the tail insulator (7), and an annular front end pressure plate (3) is disposed inside the outer balance bladder (4), the front end pressure plate (3) being axially supported on the inner wall of the front end of the outer balance bladder (4), characterized in that, Multiple support rods (5) are arranged circumferentially between the outer balance bag (4) and the inner balance bag (6). The two ends of the support rods (5) are respectively connected to the front end pressure plate (3) and the tail end insulator (7). There is an assembly gap between the outer diameter surface of the front and rear ends of the outer balance bag (4) and the inner diameter surface of the outer shell (8).

2. The high-temperature resistant electrical penetration downhole connector according to claim 1, characterized in that, The front end pressure plate (3) is provided with a front positioning hole (14), the tail end insulator (7) is provided with a rear positioning hole, and the two ends of the support rod (5) are respectively inserted into the front positioning hole (14) and the rear positioning hole.

3. The high-temperature resistant electrical penetration downhole connector according to claim 1, characterized in that, The end face of the front end of the inner balance bladder (6) is in contact with the insulating end cap (1), and the inner diameter surface of the front end of the inner balance bladder (6) is dynamically sealed to the outer circumferential surface of the movable top rod (9). The outer diameter surface of the front end of the inner balance bladder (6) is fitted with a non-metallic ring (2), and the outer diameter surface of the non-metallic ring (2) is in contact with the inner diameter surface of the front end pressure plate (3).

4. The high-temperature resistant electrical penetration downhole connector according to claim 3, characterized in that, The inner diameter surface of the front end pressure plate (3) is provided with an annular groove (13) to accommodate the non-metallic ring (2).

5. The high-temperature resistant electrical penetration downhole connector according to claim 1, characterized in that, The front end face of the external balance bag (4) is provided with a plurality of protrusions (15), and the protrusions (15) are in close contact with the insulating end cap (1).

6. The high-temperature resistant electrical penetration downhole connector according to claim 1, characterized in that, A protrusion (16) is provided on the outer diameter surface of the front end of the outer balance bag (4), and an assembly gap is left between the protrusion (16) and the inner diameter surface of the outer shell (8).

7. The high-temperature resistant electrical penetration downhole connector according to claim 1, characterized in that, The rear end of the outer shell (8) is provided with an annular conical surface (17), and the middle part of the outer shell (8) is provided with a clamping nut (11).

8. The high-temperature resistant electrical penetration downhole connector according to claim 7, characterized in that, The rear end of the outer shell (8) is also provided with a plurality of O-rings (18), and the O-rings (18) are located in front of the conical surface (17).

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