Underwater junction box assembly

Abstract

An underwater junction box assembly is characterized in that slidable end cover assemblies are arranged at ports of two sides of an outer shell, the slidable end cover assemblies are matched with the outer shell to form a first sealing cavity in a surrounding manner, a second sealing cavity is formed in one end, in contact with a cabin penetrating part, of the interior of an external cable, and the two sealing cavities are filled with liquid insulating materials; according to the scheme, the principle of independent sealing is adopted, the first sealing cavity, the second sealing cavity and the external seawater environment are divided into three different areas, the first sealing cavity achieves volume change through a slidable end cover assembly, and the second sealing cavity achieves volume change through deformation of an oil-filled hose elastomer in an external cable. Therefore, the effect of compressing liquid to generate pressure is achieved; the pressure in the sealing cavity and the external seawater pressure are balanced, at the moment, stress analysis is carried out on parts of all parts of the junction box, the pressure difference is very small, the requirements for materials and strength of metal structural parts are greatly reduced, and the product reliability is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of underwater connectors, in particular to an underwater junction box component which can be applied to deep sea environments. Background Art

[0002] At present, underwater junction box components are widely used in the fields of submarine observation network, deep-sea oil and gas development, etc. The underwater junction box is part of the submarine power distribution system and can meet all the requirements of signal transmission and monitoring. The junction box can be flexibly modularized and can have different configurations. According to the system requirements, the submarine cables and hose harnesses can be fully connected on site or pre-terminated in the factory.

[0003] The underwater junction box assembly requires the ability to work for a long time in a deep-sea environment. As we all know, the deep sea is a high-pressure environment, with a pressure increase of about 1MPa for every 100 meters of sea depth, which also poses a huge challenge to the sealing of the junction box device. Therefore, it is necessary to provide a pressure balance structure to reduce the pressure difference between the inside and outside of the junction box assembly. The main principle of pressure balance technology is based on the compressible properties of liquids. By changing the volume of the sealed cavity, the internal liquid is compressed, thereby increasing the environmental pressure inside the sealed cavity. At present, the research on pressure-balanced plug-in connectors in China is still in its infancy. As a product used in conjunction with pressure-balanced wet-plug connectors, there are relatively few manufacturers that can develop and produce such underwater junction box assemblies.

[0004] Junction box assembly devices on the market generally adopt the form of dry cabins, which completely rely on the material strength of the metal structural parts to withstand the pressure of external seawater. On the one hand, the product wall thickness is relatively thick and the weight is heavy, which is not conducive to transportation and installation; on the other hand, due to the relatively large external environmental pressure, the material strength of the junction box, the sealing structure design and the processing accuracy are particularly high. In addition, the service life of the sealing rubber ring will be greatly reduced under the action of large pressure, and the seal is likely to fail, resulting in low product reliability. Utility Model Content

[0005] In order to solve the above technical problems, the utility model provides an underwater junction box assembly, which improves the reliability of product sealing and further increases the service life of the product.

[0006] The technical solution adopted by the utility model is:

[0007] An underwater junction box assembly comprises an outer shell having an inner cavity, and penetration components for achieving electrical connection with external cables are respectively provided at the two side ends of the outer shell, and slidable end cover components are also provided at the two side ports of the outer shell. The slidable end cover components are installed on support columns located in the inner cavity of the outer shell through connectors, and a first sealed cavity surrounded by the end cover assembly and the outer shell is filled with liquid insulating material. A second sealed cavity is provided at the end of the external cable in contact with the penetration component, and the second sealed cavity is filled with liquid insulating material.

[0008] As a preferred embodiment, the slidable end cover assembly includes an end cover installed at the port of the outer shell through a sealing unit and a cover plate fixedly connected to the outside of the end cover. One end of the connecting piece passes through a reserved hole on the end cover and is tightened on the support column. The end cover can have a certain sliding space along the direction defined by the connecting piece.

[0009] As a preferred solution, the end cover is installed on the support column by means of a fixing screw. One side of the end cover is provided with a mounting hole for accommodating the end of the support column, and the other side of the end cover is provided with a mounting hole for accommodating the end of the fixing screw. The limiting boss in the end cover can slide along the axis of the fixing screw, and its sliding distance is constrained within the range defined by the end of the support column and the end of the fixing screw.

[0010] As a preferred solution, a mounting groove for mounting a sealing ring is provided on the circumferential surface where the support column and the end cover cooperate.

[0011] As a preferred solution, a plurality of wire clamps are installed on the support column inside the outer shell.

[0012] As a preferred solution, the external cable includes a conductor unit and a hose electrically connected to the cabin penetration component, and the hollow inner cavity of the hose is the second sealed cavity for being filled with liquid insulating material.

[0013] As a preferred solution, a part of the cabin-penetrating component extending out of the outer shell is connected to a sealing sleeve, and the sealing sleeve is fixedly mounted on the cabin-penetrating component by a locking piece. The external cable is installed in the sealing sleeve, and the internal wire unit passes through the sealing sleeve and is welded to the cabin-penetrating component to achieve transmission of electrical signals and power.

[0014] As a preferred solution, the outer shell is provided with a plurality of oil filling holes, and oil filling screws are installed in the oil filling holes.

[0015] As a preferred solution, the liquid insulating material is insulating oil.

[0016] The beneficial effects of the utility model are:

[0017] This scheme optimizes the composition structure and shape of the underwater junction box assembly, specifically: a slidable end cover assembly is set at the two side ports of the outer shell, the slidable end cover assembly cooperates with the outer shell to form a first sealed cavity, and a second sealed cavity is provided at the end of the external cable that contacts the cabin penetration component, and both sealed cavities are filled with liquid insulating materials. This scheme adopts the principle of independent sealing, so that the first sealed cavity, the second sealed cavity and the external seawater environment are divided into three different areas, wherein the first sealed cavity realizes the volume change through the slidable end cover assembly, thereby compressing the liquid to provide pressure; the second sealed cavity realizes the volume change through the deformation of the elastic body of the oil-filled hose in the external cable, thereby achieving the effect of compressing the liquid to generate pressure; finally, the pressure in the first sealed cavity and the second sealed cavity reaches a balance with the external seawater pressure, at this time, the components of each part of the junction box are subjected to force analysis, the pressure difference is very small, and the material and strength requirements for metal structural parts are greatly reduced, which reduces the cost and improves the product reliability. On the other hand, for the sealing O-ring, the use pressure is reduced, thereby increasing the service life.

[0018] Furthermore, the structure of the slidable end cover assembly is optimized and designed, and the end cover is installed on the support column through a connecting piece. One side of the end cover is provided with a mounting hole for accommodating the end of the support column, and the other side of the end cover is provided with a mounting hole for accommodating the end of the fixing screw. The limiting boss in the end cover can slide along the axis of the connecting piece, and its sliding distance is constrained within the range defined by the end of the support column and the end of the fixing screw. This scheme can control the axial movable distance of the end cover by adjusting the matching clearance among the limiting boss, the support column and the connecting piece. When the external environmental pressure changes or the temperature changes, the end cover can slide outward or inward, thereby realizing a change in pressure. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 It is a structural schematic diagram of an underwater junction box assembly;

[0021] Figure 2 It is a schematic diagram of the structure of the connection between the sealing sleeve and the cabin penetration component;

[0022] Figure 3 It is a structural schematic diagram of the coordination between the end cover and the support column.

[0023] Markings in the figure: 1. cover plate, 2. end cover, 21. limiting boss, 3. support column, 4. wire clamp, 5. oil filling screw, 6. outer shell, 7. fixing screw, 8. cabin penetration component, 9. sealing sleeve, 91. tightening screw, 10. external cable, 11. first sealing chamber, 12. second sealing chamber. DETAILED DESCRIPTION

[0024] The present invention is described in detail below by way of exemplary embodiments. However, it should be understood that, without further description, elements, structures and features in one embodiment may also be beneficially combined in other embodiments.

[0025] It should be noted that: unless otherwise defined, the technical terms or scientific terms used in this article should be understood by people with ordinary skills in the technical field to which the utility model belongs. The words "one", "an" or "the" and the like used in the patent application specification and claims of this utility model do not express quantitative limitations, but indicate the existence of at least one. "Include" or "comprise" and the like indicate that the elements or objects appearing before "include" or "comprises" include the elements or objects listed after "include" or "comprises" and their equivalents, but do not exclude other elements or objects with the same function.

[0026] Embodiment 1,

[0027] The following is combined with Figure 1-3 The specific structure and working process of the underwater junction box assembly are described in detail:

[0028] like Figure 1As shown, an underwater junction box assembly can be installed on a panel by two U-bolts, and is mainly composed of a cover plate 1, an end cover 2, a support column 3, a wire clamp 4, an oil injection screw 5, an outer shell 6, a fixing screw 7, a cabin penetration component 8 and a sealing sleeve 9, wherein the outer shell 6 has a hollow inner cavity, the support column 3 is fixedly arranged in the inner cavity of the outer shell 6, a plurality of wire clamps 4 are installed on the support column 3, and the end cover 2 is installed at the ports on both sides of the outer shell 6 in cooperation with the sealing assembly so that the outer shell 6 is hollow. The inner cavity forms a first sealed cavity 11, and the first sealed cavity 11 is filled with liquid insulating material. The cover plate 1 is fixedly connected to the outer surface of the end cover 2 by screws. The end cover 2 is installed on the support column 3 located in the inner cavity of the outer shell 6 through a connecting piece, and the end cover 2 is allowed to have a certain sliding space along the direction defined by the connecting piece. The cover plate 1 and the end cover 2 constitute a slidable end cover assembly as a whole. One side of the cabin penetration component 8 passes through the reserved hole on the cover plate 1 and is fixedly installed in the installation hole of the end cover 2. The sealing sleeve 9 is fixedly installed. Installed on the end of the cabin penetration component 8 extending out of the cover plate 1, the conductive unit of the external cable 10 and the cabin penetration component 8 are welded to achieve the transmission of electrical signals and power. The end of the external cable 10 in contact with the cabin penetration component 8 has a second sealed cavity 12, wherein the second sealed cavity 12 is filled with liquid insulating material. This scheme adopts the principle of independent sealing, so that the first sealed cavity 11, the second sealed cavity 12 and the external seawater environment are divided into three different areas, wherein the first sealed cavity 11 realizes the change of volume through the slidable end cover assembly, thereby compressing the liquid to provide pressure; the second sealed cavity 12 realizes the change of volume through the deformation of the elastic body of the oil-filled hose in the external cable, thereby achieving the effect of compressing the liquid to generate pressure; finally, the pressure in the first sealed cavity and the second sealed cavity reaches a balance with the external seawater pressure, at this time, the components of each part of the junction box are subjected to force analysis, the pressure difference is very small, and the material and strength requirements for metal structural parts are greatly reduced, which reduces the cost and improves the product reliability. On the other hand, for the sealing O-ring, the use pressure is reduced, thereby increasing the service life.

[0029] It should be noted that: in this embodiment, Figure 1 As shown, three external cables 10 are connected to both sides of the underwater junction box assembly, and a second sealed cavity 12 is provided inside each external cable 10 .

[0030] In this embodiment, Figure 2 As shown, one side of the sealing sleeve 9 is fixedly mounted on the cabin penetration component 8 by a set screw 91, and a sealing unit is provided between the two. The end of the cabin penetration component 8 cooperates with the sealing sleeve 9, the sealing unit and the inner cavity of the oil-filled hose in the external cable to form a second sealing cavity 12. Therefore, when the junction box assembly enters the deep sea, as the external pressure increases, the pressure can be transmitted to the oil-filled hose, causing the volume of the second sealing cavity 12 to decrease.

[0031] In this embodiment, Figure 3 As shown, the end cover 2 is mounted on the support column 3 by means of a fixing screw 7. The circumferential surface of the support column 3 and the end cover 2 is provided with a mounting groove for mounting an O-ring, and the end cover is allowed to have a certain sliding space. The specific arrangement is as follows: one side of the end cover 2 is provided with a mounting hole for accommodating the end of the support column, and the other side of the end cover 2 is provided with a mounting hole for accommodating the end of the fixing screw. The limiting boss 21 in the end cover can slide along the axis of the fixing screw 7, and its sliding distance is constrained within the range defined by the end of the support column and the end of the fixing screw, as shown in FIG. Figure 3 As shown, the reserved axial length x is the sliding space allowed for the end cover 2.

[0032] In this embodiment, a plurality of mounting grooves are provided on the circumferential surface of the end cover 2 that cooperates with the inner wall of the outer shell 6, and an O-type sealing ring is matched in each mounting groove.

[0033] It should be noted that the external cable 10 is also called an oil-filled cable, which includes a rubber oil-filled hose and a wire unit, wherein the wire and the cabin penetration component 8 in the junction box are welded to achieve the transmission of electrical signals and power, and the rubber oil-filled hose is located between the sealing sleeve and the connecting sleeve, and the sealing is achieved by tightening and squeezing the threads, and the inner cavity of the rubber oil-filled hose is the second sealing cavity filled with liquid insulating material.

[0034] In this embodiment, the liquid insulating material is insulating oil, for example, silicone oil can be selected as the insulating medium to fill the two sealed cavities.

[0035] In this embodiment, the outer shell 6 is provided with a plurality of oil filling holes, and oil filling screws 5 are installed in the oil filling holes, and insulating oil can be filled into the outer shell 6 through the oil filling holes.

[0036] The structure defined in this solution protects the overall seal of the junction box and can be used in a high-pressure environment of 3000m underwater and an external pressure of nearly 30MPa. Assuming that the design principle of pressure balance is not adopted, all shell parts need to withstand a pressure of 30MPa, which will place particularly high requirements on shell material and strength design. In addition, the sealing of most areas of the junction box is almost achieved by O-rings. Under such high pressure, the O-rings are likely to be sheared and damaged, resulting in sealing failure.

[0037] The specific implementation process of the underwater junction box assembly is as follows:

[0038] Before the entire junction box assembly is placed in the deep sea for use, it needs to withstand a hydrostatic pressure of 30 MPa. The components are sealed by O-rings. In order to reduce the pressure difference, the first sealing cavity 11 and the second sealing cavity 12 are filled with insulating oil.

[0039] When the junction box is lowered, as the depth of the seawater increases, the external pressure becomes greater and greater, and the end cover of the junction box slides inward, causing the volume of the first sealed cavity 11 to decrease and the liquid pressure to increase;

[0040] As the depth of seawater increases, the external pressure increases, and the pressure is transmitted to the oil-filled hose, causing the volume of the second sealed chamber 12 to decrease, causing the internal liquid pressure to increase;

[0041] Finally, the pressure of the first sealed cavity 11 and the second sealed cavity 12 reaches a balance with the external seawater pressure. At this time, the stress analysis of the components of each part of the junction box is carried out. The pressure difference is very small, and the material and strength requirements of the metal structural parts are greatly reduced, which reduces the cost and improves the product reliability. On the other hand, for the sealing O-ring, the use pressure is reduced, thereby increasing the service life.

[0042] The parts not described in detail in this embodiment are prior art.

[0043] It should be noted that although the utility model is described through the above embodiments, the utility model can also have other multiple embodiments. Without departing from the spirit and scope of the utility model, it is obvious that those skilled in the art can make various corresponding changes and deformations to the utility model, but these changes and deformations should all fall within the scope of protection of the attached claims of the utility model and their equivalents.

Claims

1. An underwater junction box assembly, comprising an outer shell (6) having an inner cavity, and two side ends of the outer shell (6) are respectively provided with a penetration component (8) for achieving electrical connection with an external cable (10), characterized in that: The outer shell (6) is also provided with slidable end cover assemblies at both side ports. The slidable end cover assemblies are mounted on support columns (3) located in the inner cavity of the outer shell (6) via connectors. A first sealed cavity (11) surrounded by the end cover assemblies and the outer shell (6) is filled with liquid insulating material. A second sealed cavity (12) is provided at one end of the outer cable (10) in contact with the cabin penetration component (8). The second sealed cavity (12) is filled with liquid insulating material.

2. An underwater junction box assembly according to claim 1, characterized in that: The slidable end cover assembly comprises an end cover (2) mounted at the port of the outer shell through a sealing unit and a cover plate (1) fixedly connected to the outside of the end cover, one end of the connecting piece passes through a reserved hole on the end cover (2) and is screwed onto a support column (3), and the end cover (2) has a certain sliding space along the direction defined by the connecting piece.

3. An underwater junction box assembly according to claim 2, characterized in that: The end cover (2) is mounted on the support column (3) by means of a fixing screw (7); a mounting hole for accommodating the end of the support column is provided on one side of the end cover (2); a mounting hole for accommodating the end of the fixing screw is provided on the other side of the end cover (2); a limiting boss (21) in the end cover can slide along the axis of the fixing screw (7); and a sliding distance thereof is constrained within a range defined by the end of the support column and the end of the fixing screw.

4. An underwater junction box assembly according to claim 1 or 2, characterized in that: A mounting groove for mounting a sealing ring is provided on the circumferential surface where the support column (3) and the end cover (2) cooperate.

5. An underwater junction box assembly according to claim 1 or 2, characterized in that: A plurality of wire clamps (4) are installed on the support column (3) inside the outer shell.

6. An underwater junction box assembly according to claim 1, characterized in that: The external cable (10) comprises a conductor unit and a hose electrically connected to the cabin penetration component (8), and the hollow inner cavity of the hose is a second sealed cavity for being filled with liquid insulating material.

7. An underwater junction box assembly according to claim 1 or 6, characterized in that: A portion of the cabin-penetrating component (8) extending outside the outer shell (6) is connected to a sealing sleeve (9), and the sealing sleeve (9) is fixedly mounted on the cabin-penetrating component (8) via a locking member. An external cable is mounted in the sealing sleeve, and an internal wire unit passes through the sealing sleeve and is welded to the cabin-penetrating component to achieve transmission of electrical signals and power.

8. The underwater junction box assembly according to claim 1, characterized in that: The outer shell (6) is provided with a plurality of oil filling holes, and oil filling screws (5) are installed in the oil filling holes.

9. The underwater junction box assembly according to claim 1, characterized in that: The liquid insulating material is insulating oil.

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