An undersea cable splice closure and method of assembling and potting

Abstract

The present application relates to submarine communication equipment and submarine optical cable joint protection technical field, especially in kind submarine optical cable joint box and assembly glue injection method. Wherein the submarine optical cable joint box includes split type box body, armored force component and optical fiber storage component. Two half shells are buckled to form main containing cavity, end force fixing cavity and two potting anchoring cavities; the main containing cavity contains the optical fiber storage component, and the two potting anchoring cavities are respectively provided with end vacuum hole, middle glue injection hole and middle vacuum hole. The armored force component includes split type conical force seat, clamping piece and locking piece, the outer periphery of the force seat is provided with steel wire positioning groove, and the outer armored steel wire is dispersed and placed into and is pressed tightly by the clamping piece. When the two half shells are separated, the optical cable, the force component and the optical fiber storage component can be radially loaded. The present application has the advantages of convenient assembly, reliable sealing and optimized force path.

Description

Technical Field

[0001] This invention relates to the field of submarine communication equipment and submarine optical cable splice protection technology, and in particular to a submarine optical cable splice box and assembly and adhesive injection method that can perform radial assembly, armor bearing capacity, composite sealing and adhesive injection testing under the condition that the submarine optical cable has been laid or is inconvenient to axially insert. Background Technology

[0002] Submarine optical cables are key transmission carriers for transoceanic communication, marine observation, submarine equipment networking, and marine engineering systems. Submarine optical cable junction boxes are used for splicing, branching, emergency repair, or maintenance between optical cables. Their watertightness, tensile strength, and on-site assembly reliability directly affect the long-term stability of submarine communication links.

[0003] Existing submarine optical cable splice closures typically employ an integrated cylindrical structure or an axially fitted end cap structure. During assembly, the optical cable needs to be threaded through one end of the splice closure, followed by the sequential installation of the armor, seals, fiber optic cable tray, and electrical connectors. When components are missing, incorrectly installed, the armor is mispositioned, or the fiber optic cable is abnormally coiled during assembly, it is often necessary to remove the installed components. In severe cases, it may even be necessary to cut the optical cable and remake the splice, resulting in a "cable-cutting and rework" problem, significantly increasing offshore operation time, material waste, and construction risks.

[0004] Ordinary land-based or shallow-water optical cable junction boxes often feature top and bottom cover opening or Haver-type structures, which improve assembly convenience. However, these structures typically rely mainly on rubber rings, sealing strips, or radial clamping components for box sealing, lacking armor load-bearing paths, load-bearing and sealing decoupling structures, and sealant filling quality control structures specifically designed for long-term subsea service scenarios. In deep-sea environments, water pressure circulation, temperature circulation, ocean current disturbances, laying tension, and maintenance towing forces can all cause sealing interface peeling, joint surface cracking, or armor wire eccentric load failure.

[0005] Existing submarine junction boxes also employ wedge-shaped components, inner clamps, outer clamps, or end cap armor structures to clamp the armor wires of submarine optical cables. These solutions are typically suitable for axially sleeved structures, where the armor clamps, end caps, and seals are sequentially installed along the cable's axis. While this improves armor fixation, it is unsuitable for on-site repairs of already laid submarine optical cables or those inconvenient to cut and re-sleeve. Furthermore, it makes it difficult to radially insert, inspect, and correct components while the junction box is open.

[0006] Existing potting sealants typically fill the cable entry area or sealing gaps with potting compound, encapsulating the optical cable and bonding it to the inner wall of the enclosure. The sealing reliability of this method largely depends on the interfacial adhesion between the potting compound and the inner wall of the enclosure, as well as the experience of the installer. If air remains in the cavity during the potting process or if areas are not fully filled, hidden water seepage channels can easily form. Traditional methods of observing the compound through overflow holes are prone to causing overflow contamination and are not conducive to actively removing air bubbles from narrow joint surfaces or enclosed injection cavities.

[0007] Therefore, there is an urgent need for a type of openable submarine optical cable junction box that can be opened for assembly, inspection and correction on-site, just like a regular openable junction box, while also meeting the requirements for radial assembly, circumferential load bearing, separation of load-bearing path and sealing path, double-seal constraint injection and negative pressure assisted filling detection required for long-term service of submarine optical cables. Summary of the Invention

[0008] Therefore, the technical problem to be solved by the present invention is to overcome the problems in the prior art, thereby providing a submarine optical cable junction box and an assembly and gluing method.

[0009] Firstly, a submarine optical cable junction box is provided, comprising: The split-type housing includes a first half-shell and a second half-shell; the first half-shell and the second half-shell are fastened together to form a main receiving cavity, and an end load-bearing fixing cavity, an end potting and anchoring cavity, and an in-cell potting and anchoring cavity are respectively formed at both ends along the axial direction; the main receiving cavity is used to accommodate the optical fiber housing assembly; the end potting and anchoring cavity has an end vacuum hole; the in-cell potting and anchoring cavity has a central glue injection hole and a central vacuum hole; The armored load-bearing assembly includes a split conical load-bearing base, a split clamping component, and a locking component. The outer periphery of the split conical load-bearing base is provided with multiple wire positioning grooves. The outer armor wires of the submarine optical cable radiate circumferentially within the end load-bearing fixing cavity and are respectively inserted into the wire positioning grooves. The split clamping component is located on the outside of the outer armor wires, and the locking component causes the split clamping component to press the outer armor wires tightly against the split conical load-bearing base. The end-filled anchoring cavity is located on the side of the armored load-bearing component that is close to the external seawater, and is used to accommodate and cover the submarine optical cable before the outer armor steel wire is separated. The internal filling and anchoring cavity is located on the side of the armored load-bearing component near the main receiving cavity, and is used to accommodate and cover the submarine optical cable after the outer armor steel wires are separated. When the first half-shell is separated from the second half-shell, the submarine optical cable, the armored load-bearing assembly, and the optical fiber housing assembly can be installed radially.

[0010] In one embodiment of the present invention, a double-sealing adhesive strip structure is provided at the joint surface of the first half-shell and the second half-shell; the double-sealing adhesive strip structure includes an inner sealing strip and an outer sealing strip.

[0011] In one embodiment of the present invention, the split conical bearing seat includes at least two conical segments that can be radially engaged; the outer periphery of the conical segments is provided with a plurality of steel wire positioning grooves.

[0012] In one embodiment of the present invention, the split conical bearing seat is provided with a bearing shoulder.

[0013] In one embodiment of the present invention, the inner walls of the ends of the first half-shell and the second half-shell are respectively provided with semi-annular load-bearing steps, which are fastened together to form annular load-bearing steps; the load-bearing shoulder abuts against the annular load-bearing step along the axial direction, so that the axial tension of the submarine optical cable is transmitted to the split-type box body through the outer armor steel wire, the split conical load-bearing seat, the load-bearing shoulder and the annular load-bearing step.

[0014] In one embodiment of the present invention, the load-bearing shoulder and the annular load-bearing step are in surface contact, and the step width of the annular load-bearing step satisfies the following formula: ; in, The width of the ring-shaped load-bearing step. The load safety factor for the split-type box structure, The design axial tensile force for the split-type box body. The average radius of the semi-circular load-bearing step. This represents the allowable contact compressive stress of the split-type box material.

[0015] Secondly, an assembly and adhesive injection method is provided for assembling the aforementioned submarine optical cable junction box, comprising the following steps: Open the first half-shell and the second half-shell, and put the pre-treated submarine optical cable into the second half-shell; Install the split conical bearing seat, split clamping parts and locking parts radially so that the outer armor steel wires of the submarine optical cable radiate outward in the end bearing fixing cavity and are respectively placed into the steel wire positioning grooves of the split conical bearing seat, pressing the outer armor steel wires and making the bearing shoulder abut against the annular bearing step. Complete the connection of the optical unit and fiber optic housing assembly of the submarine optical cable; The first and second half-shells are fastened together, and the locking assembly is tightened to the set torque. Vacuum is drawn into the cavity and / or end cavity of the encapsulation anchoring chamber through the vacuum hole, and sealant is injected into the cavity and end cavity through the middle injection hole, so that the sealant fills the cavity and end cavity under the combined action of negative pressure traction and injection pressure.

[0016] In one embodiment of the present invention, when injecting sealant into the sealing anchor cavity inside the chamber or the end sealing anchor cavity, the amount of sealant injected is controlled by the following formula: ; in, This refers to the glue injection flow rate. This refers to the glue application time. The fill margin coefficient and Greater than 1, The effective volume of the cavity for filling and anchoring within the chamber or the cavity for filling and anchoring at the end.

[0017] In one embodiment of the present invention, the method further includes the step of: performing a pressure holding test through a vacuum hole before and / or after injecting the sealant; assuming the initial pressure during the holding time is... The termination pressure is When the following conditions are met: If the airtightness of the sealed anchoring cavity within the chamber and its inner and outer sealing boundaries or the end sealed anchoring cavity and its inner and outer sealing boundaries is determined to be good, then... and These represent the start and end times of the hold time, respectively. The allowable pressure recovery threshold for vacuum holding pressure testing is obtained through calibration.

[0018] Compared with the prior art, the above-described technical solution of the present invention has the following advantages: The submarine optical cable junction box of the present invention achieves radial insertion of components by adopting a split box design, and combines the axial tensile force transmission of the split armored load-bearing component with the optimization of the sealant filling path by the special potting cavity. It effectively solves the problems of difficult on-site assembly and error correction, easy peeling of the sealing interface and failure of load-bearing in deep sea. It has the advantages of convenient assembly, reliable sealing and optimized load-bearing path. Attached Figure Description

[0019] To make the content of this invention easier to understand, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0020] Figure 1 This is a schematic diagram of the submarine optical cable junction box in this invention; Figure 2 This is a side view of the submarine optical cable junction box in this invention; Figure 3 yes Figure 2 Sectional view at point AA; Figure 4 This is an exploded view of the submarine optical cable junction box in this invention; Figure 5 This is a first-view structural schematic diagram of the armored load-bearing component in this invention; Figure 6 This is a second-view structural schematic diagram of the armored load-bearing component in this invention; Figure 7 This is a front view of the armored load-bearing component in this invention; Figure 8 yes Figure 7 Sectional view at point BB; Figure 9 This is an exploded view of the armored load-bearing component in this invention; Figure 10 This is an exploded view of the split-type clamping component in this invention.

[0021] Explanation of reference numerals in the instruction manual: 100. Submarine optical cable junction box; 110. Split-type box body; 111. First half-shell; 112. Second half-shell; 113. Main receiving cavity; 114. Central vacuum hole; 115. Central glue injection hole; 116. Locking assembly; 117. Sealing plug; 118. Semi-annular load-bearing step; 119. End load-bearing fixing cavity; 120. End vacuum hole; 131. In-cell potting and anchoring cavity; 132. End potting and anchoring cavity; 140. Armored load-bearing assembly; 141. Split-type conical load-bearing seat; 142. Conical segment; 143. Steel wire positioning groove; 144. Split-type clamping component; 145. Locking component; 146. Load-bearing shoulder; 150. Double sealing strip structure for joint surface; 160. Optical fiber housing assembly; 200. Submarine optical cable; 201. Outer armor steel wire; 202. Optical unit. Detailed Implementation

[0022] This will allow for a better understanding and implementation of the present invention, but the examples given are not intended to limit the invention.

[0023] Existing submarine optical cable junction boxes, due to their integrated or axially fitted structures, often require "cable cutting and rework" when components are missing, misinstalled, or the fiber optic cable is abnormally coiled, significantly increasing operational risks. Ordinary open-type structures lack adequate armor load-bearing capacity, load-bearing and sealing decoupling, and sealant filling quality control for deep-sea environments. Axially fitted press-armored structures are unsuitable for on-site repairs and make radial component placement difficult. Existing potting seals rely on experience, are prone to air residue or incomplete filling, creating seepage channels, and traditional methods of observing excess sealant are ineffective for venting.

[0024] In this regard, combined with Figures 1 to 4 This embodiment proposes a submarine optical cable junction box 100, comprising: The split-type housing 110 includes a first half-shell 111 and a second half-shell 112; the first half-shell 111 and the second half-shell 112 are fastened together to form a main receiving cavity 113, and an end load-bearing fixing cavity 119, an end potting and anchoring cavity 132, and an in-cell potting and anchoring cavity 131 are respectively formed at both ends of the axial direction; the main receiving cavity 113 is used to accommodate the optical fiber housing assembly 160; the end potting and anchoring cavity 132 is provided with an end vacuum hole 120; the in-cell potting and anchoring cavity 131 is provided with a central glue injection hole 115 and a central vacuum hole 114; The armored load-bearing assembly 140 includes a split conical load-bearing base 141, a split clamping member 144, and a locking member 145. The outer periphery of the split conical load-bearing base 141 is provided with multiple steel wire positioning grooves 143. The outer armor steel wires 201 of the submarine optical cable 200 radiate outward in the end load-bearing fixing cavity 119 and are respectively placed into the steel wire positioning grooves 143. The split clamping member 144 is disposed on the outside of the outer armor steel wires 201, and the locking member 145 causes the split clamping member 144 to press the outer armor steel wires 201 tightly against the split conical load-bearing base 141. Among them, the end-filled anchoring cavity 132 is located on the side of the armored load-bearing component 140 near the external seawater, and is used to accommodate and cover the submarine optical cable 200 before the outer armor steel wire 201 is separated. The internal filling and anchoring cavity 131 is located on the side of the armored load-bearing component 140 near the main receiving cavity 113, and is used to receive and cover the submarine optical cable 200 after the outer armor steel wire 201 is separated. When the first half-shell 111 separates from the second half-shell 112, the submarine optical cable 200, the armored load-bearing assembly 140 and the optical fiber housing assembly 160 can be installed radially.

[0025] For ease of understanding, the following explains some key terms in this embodiment: The split-type housing 110 refers to a structure formed by at least two separable half-shells (e.g., a first half-shell 111 and a second half-shell 112) being joined together. This design is intended to facilitate the radial assembly, inspection, and maintenance of internal components.

[0026] The main housing 113 refers to the internal space formed after the split-type housing 110 is snapped together. Its main function is to provide a protective and housing environment for the optical fiber housing assembly 160 and ensure the safety of the optical fiber splice point.

[0027] The end bearing fixing cavity 119 refers to the cavity formed at both ends of the split box 110 along the axis. Its function is to accommodate and fix the outer armor steel wire 201 of the submarine optical cable 200, and to transfer the axial tension of the optical cable to the box structure through the armor bearing component 140.

[0028] The end-filled anchoring cavity 132 refers to the cavity located on the side of the armored load-bearing assembly 140 closest to the external seawater. Sealant is injected into the cavity to encapsulate and anchor the submarine optical cable 200, whose outer armor wires 201 have not been separated, providing watertightness and additional load-bearing protection. The cavity is equipped with an end-vacuum hole 120 for performing a vacuuming operation before filling, thereby improving the filling quality.

[0029] The internal sealing and anchoring cavity 131 refers to the cavity located on the side of the armored load-bearing component 140 near the main receiving cavity 113. Inside, sealant is injected to wrap and anchor the submarine optical cable 200, whose outer armor steel wires 201 have been separated, further enhancing its sealing and load-bearing performance. The cavity has a central sealant injection hole 115 and a central vacuum hole 114 for sealant injection and vacuuming operations.

[0030] The armored load-bearing assembly 140 refers to the structure used to secure the outer armor steel wire 201 of the submarine optical cable 200 and to transfer the axial tensile force of the optical cable to the split-type housing 110. Its design aims to ensure the long-term stability and tensile strength of the optical cable in the deep-sea environment.

[0031] The split-type conical load-bearing seat 141 is a core component of the armored load-bearing assembly 140, which is typically composed of multiple segments and can be installed radially. The outer periphery of the load-bearing seat is provided with a wire positioning groove 143 for precisely guiding and fixing the outer armor wire 201 of the submarine optical cable 200.

[0032] The steel wire positioning groove 143 refers to the groove set on the outer periphery of the split conical bearing seat 141. Its function is to make the outer armor steel wire 201 of the submarine optical cable 200 evenly dispersed in the circumferential direction and accurately placed in the end bearing fixing cavity 119, thereby realizing the circumferential load distribution of the outer armor steel wire 201.

[0033] The split clamping component 144 is a component located on the outside of the outer armor steel wire 201. It cooperates with the split conical bearing seat 141 and, through the action of the locking component 145, tightly presses the outer armor steel wire 201 into the steel wire positioning groove 143 to achieve reliable fixation.

[0034] Locking element 145 refers to a component, such as a bolt or clamp, used to apply a clamping force to the split clamping element 144 so that it securely fixes the outer armor wire 201 to the split conical bearing seat 141.

[0035] The fiber optic housing assembly 160 refers to a component used to orderly house, protect and manage the optical units 202 inside the submarine optical cable 200 and to provide space for fiber optic splicing, such as a fiber optic housing tray.

[0036] Submarine optical cable 200 refers to a special optical cable used for submarine communication or observation. It typically includes an internal optical unit 202 and an external protective layer, such as an outer armor steel wire 201.

[0037] The outer armor steel wire 201 refers to the outer reinforcing layer of the submarine optical cable 200, which is usually composed of high-strength steel wires and is used to provide tensile strength and mechanical protection for the optical cable.

[0038] This embodiment provides a submarine optical cable junction box 100. The split-type box body 110 is composed of a first half-shell 111 and a second half-shell 112, which are fastened together to form a complete box body. Alternatively, the first half-shell 111 and the second half-shell 112 can be simply connected by bolts to close the box body. After fastening, a main receiving cavity 113 is formed inside the box body to accommodate the optical fiber receiving assembly 160. Furthermore, at both axial ends of the box body, an end load-bearing fixing cavity 119, an end potting anchoring cavity 132, and an in-cavity potting anchoring cavity 131 are formed, respectively. This split-type structure allows internal components, such as the submarine optical cable 200, the armored load-bearing assembly 140, and the optical fiber receiving assembly 160, to be conveniently installed or removed radially when the first half-shell 111 and the second half-shell 112 are separated, thereby simplifying the on-site assembly and maintenance process.

[0039] The end-filled anchoring cavity 132 has an end vacuum hole 120, while the inner-filled anchoring cavity 131 has a central injection hole 115 and a central vacuum hole 114. These holes can be designed as simple circular openings for vacuuming and injecting sealant during the filling process. For example, before filling, the cavity can be evacuated through the end vacuum hole 120 and the central vacuum hole 114 to reduce residual air; subsequently, sealant is injected through the central injection hole 115. It should be noted that after the sealant is injected, the central injection hole 115 is fitted with a sealing plug 117.

[0040] The armored load-bearing assembly 140 includes a split conical load-bearing base 141, a split clamping member 144, and a locking member 145. The split conical load-bearing base 141 may be composed of two or more conical segments 142, which close radially during assembly. The outer periphery of the split conical load-bearing base 141 is provided with multiple wire positioning grooves 143, which may be designed as simple V-shaped grooves, for guiding the outer armor wires 201 of the submarine optical cable 200. The split clamping member 144 is located on the outside of the outer armor wires 201 and is pressed against them by the locking member 145 (e.g., a clamp), so that the outer armor wires 201 are fixed on the split conical load-bearing base 141.

[0041] An end-filled anchoring cavity 132 is located on the side of the armored load-bearing assembly 140 closest to the external seawater. The cavity is used to accommodate and enclose the submarine optical cable 200 before the outer armor wires 201 are separated. During the filling process, sealant is injected into the cavity, forming a seal and anchoring effect on the optical cable. The inner wall of the cavity can be designed as a smooth surface, and the sealant achieves sealing and anchoring primarily through adhesion between the sealant and the outer surface of the optical cable and the inner wall of the cavity.

[0042] The internal potting and anchoring cavity 131 is located on the side of the armored load-bearing assembly 140 near the main receiving cavity 113. The cavity is used to house and cover the submarine optical cable 200 after the outer armor steel wire 201 has been separated. Similar to the end potting and anchoring cavity 132, sealant is injected into the cavity to seal and anchor the optical cable. The inner wall of the cavity can also be designed as a smooth surface, relying on the adhesive properties of the sealant.

[0043] The submarine optical cable splice 100 of this embodiment effectively solves the problem of "cutting and redoing" caused by traditional integrated or axially assembled structures by adopting a split-type cassette 110 and a radial assembly method, significantly improving the convenience of on-site assembly, inspection, and error correction. Meanwhile, the combination of the armored load-bearing component 140 with the double-filled anchoring cavities, namely the in-cabin filler anchoring cavity 131 and the end filler anchoring cavity 132, as well as the placement of the central vacuum hole 114, the end vacuum hole 120, and the central glue injection hole 115, ensures the watertightness, tensile strength, and filling quality of the optical cable splice cassette in deep-sea environments, avoiding the risk of seal failure and water leakage caused by factors such as water pressure circulation and temperature circulation.

[0044] It should be noted that, in this embodiment, the axial direction refers to the extension direction of the submarine optical cable 200 or the length direction of the junction box; the radial direction refers to the direction perpendicular to the axial direction and toward or away from the center line of the submarine optical cable 200; the circumferential direction refers to the circumferential direction around the center line of the submarine optical cable 200; and the upper and lower parts refer to the relative positions of the junction box in the predetermined assembly and glue injection posture.

[0045] This embodiment further proposes a scheme in which the first half-shell 111 and the second half-shell 112 are fixedly connected by a locking assembly 116.

[0046] The locking assembly 116 is a mechanical device used to securely connect the first half-shell 111 and the second half-shell 112 together. Its function is to provide sufficient clamping force or connection strength to resist external loads and ensure that the first half-shell 111 and the second half-shell 112 do not move relative to each other or separate after being engaged. The locking assembly 116 can be implemented in various forms; for example, it can be a series of bolts and nuts evenly distributed circumferentially along the split housing 110, tightened by a preset torque to ensure a tight fit between the first half-shell 111 and the second half-shell 112. In some embodiments, the locking assembly 116 may also integrate an anti-loosening mechanism to cope with loosening that may be caused by long-term underwater vibration and temperature changes.

[0047] A fixed connection refers to a rigid or semi-rigid connection between the first half-shell 111 and the second half-shell 112, allowing them to work together as a whole after being engaged to resist external forces. This connection ensures the stability of the geometry and internal volume of the split-type housing 110, preventing internal structural damage or sealing failure due to relative displacement of the half-shells. The fixed connection relies on the effective function of the locking assembly 116, whose connection strength and stability are crucial for the long-term reliable operation of the submarine optical cable junction box 100.

[0048] This embodiment further proposes that a double sealing strip structure 150 is provided at the joint surface of the first half-shell 111 and the second half-shell 112, and the double sealing strip structure 150 includes an inner sealing strip and an outer sealing strip.

[0049] Specifically, the double-sealable strip structure 150 refers to a composite sealing assembly disposed on the mating surfaces of the first half-shell 111 and the second half-shell 112. Its main function is to fill the minute gaps between the mating surfaces through elastic deformation after the split-type housing 110 is closed, thus blocking the path for external seawater to enter the housing. The structure is typically made of materials with good seawater corrosion resistance, pressure resistance, and elasticity, such as nitrile rubber, fluororubber, or silicone rubber. Its design should ensure stable sealing performance even under long-term water pressure.

[0050] The inner sealing strip is a sealing element in the double-sealable strip structure 150 of the mating surface, located near the internal cavity of the split-type housing 110. As the first line of defense, it directly withstands external water pressure and prevents seawater from penetrating inwards. The inner sealing strip is typically designed as an O-ring, rectangular ring, or lip seal, and its cross-sectional shape and dimensions must precisely match the corresponding groove on the mating surface to generate sufficient pre-tightening force during engagement, forming an effective seal. The outer sealing strip is another sealing element in the double-sealable strip structure 150 located outside the inner sealing strip. As the second line of defense, its main function is to block small amounts of seawater that may penetrate the inner sealing strip and to provide additional protection for the inner sealing strip, preventing external impurities or mechanical damage from affecting its integrity. The material and form of the outer sealing strip can be the same as the inner sealing strip, or they can be optimized according to actual needs, such as using a wider cross-section or different materials to enhance its resistance to external environmental corrosion.

[0051] Combination Figures 5 to 10 In this embodiment, it is further proposed that the split conical bearing seat 141 is designed to consist of at least two conical segments 142, which can be engaged radially.

[0052] Specifically, these conical segments 142 can be two semi-circular segments or three or more fan-shaped segments. This design allows the split conical support 141 to be conveniently installed from the side (i.e., radially) onto the pre-treated and radiating outer armor wires 201, avoiding the cumbersome operation of axially passing the optical cable required by traditional integrated support assemblies. Furthermore, each conical segment 142 has multiple wire positioning grooves 143 on its outer periphery. The shape of these wire positioning grooves 143 can be designed according to the cross-sectional shape of the outer armor wires 201, such as V-shape, U-shape, or other geometries that can effectively accommodate and fix the wires. They are evenly distributed along the circumference of the conical segments 142 to ensure that each radiating outer armor wire 201 can be independently and precisely positioned. The depth and width of the grooves are optimized to closely match the diameter of the outer armor wires 201, thereby providing sufficient support and effectively limiting the axial and radial displacement of the wires under stress.

[0053] Through the above technical solution, the split conical load-bearing seat 141 is designed to consist of at least two radially interlocking conical segments 142, with wire positioning grooves 143 located on the outer periphery of these conical segments 142. This effectively solves the problem that in the split-type box 110, the integral load-bearing seat is difficult to radially assemble with the diverged outer armor wires 201. This segmented structure is highly compatible with the radial assembly characteristics of the split-type box 110, greatly simplifying the installation process of the armored load-bearing assembly 140. The operator can first circumferentially diverge the outer armor wires 201 within the end load-bearing fixing cavity 119 and place them into the wire positioning grooves 143, and then radially interlock the segmented split conical load-bearing seat 141, thereby quickly and accurately completing the installation of the load-bearing seat. This not only improves assembly efficiency and reduces operational difficulty, but also ensures the precise fixation and uniform force distribution of the outer armor steel wire 201 on the bearing seat, thereby guaranteeing the reliability and stability of the submarine optical cable junction box 100 when subjected to axial tensile force.

[0054] This embodiment further proposes that the split-type conical bearing seat 141 is provided with a bearing shoulder 146. The bearing shoulder 146 is a ring-shaped or partially ring-shaped protrusion on the split-type conical bearing seat 141, and its main function is to provide an additional, positive axial bearing surface. The bearing shoulder 146 can physically abut against the corresponding structure inside the connector box, thereby directly transferring the force from the split-type conical bearing seat 141 to the box structure under axial tensile force, rather than relying solely on the frictional force generated by clamping. The bearing shoulder 146 can be integrally formed with the split-type conical bearing seat 141, or it can be fixed to the split-type conical bearing seat 141 by welding, threaded connection, or other methods to ensure its structural integrity and stability when bearing axial loads.

[0055] By providing a load-bearing shoulder 146 on the split conical load-bearing base 141, the submarine optical cable splice 100 of this embodiment can significantly enhance its axial load-bearing capacity. When the submarine optical cable 200 is subjected to axial tension, the tension is transmitted to the split conical load-bearing base 141 through the outer armor steel wire 201, and then the load-bearing shoulder 146 directly abuts against the internal structure of the split box 110, forming a reliable axial limiting and load-bearing path. This design effectively avoids the slippage problem that may be caused by relying solely on friction to transmit axial loads, improving the load-bearing efficiency and reliability of the armored load-bearing assembly 140. At the same time, the direct contact between the load-bearing shoulder 146 and the box structure allows the axial load to be distributed more evenly and effectively on the split box 110, thereby improving the long-term stability and safety of the entire submarine optical cable splice 100 in complex marine environments and ensuring the reliability of the optical cable connection.

[0056] This embodiment further proposes that the inner walls of the ends of the first half-shell 111 and the second half-shell 112 are respectively provided with semi-annular load-bearing steps 118, which form annular load-bearing steps after being fastened together; the load-bearing shoulder 146 abuts against the annular load-bearing step along the axial direction, so that the axial tension of the submarine optical cable 200 is transmitted to the split box 110 through the outer armor steel wire 201, the split conical load-bearing seat 141, the load-bearing shoulder 146 and the annular load-bearing step.

[0057] Specifically, the semi-annular load-bearing step 118 refers to a semi-annular protrusion or groove structure respectively provided on the inner wall of the end of the first half-shell 111 and the second half-shell 112. When the first half-shell 111 and the second half-shell 112 are engaged, the two semi-annular load-bearing steps 118 are precisely aligned and combined to form a complete annular load-bearing step. As a key structure inside the split-shell 110, the annular load-bearing step mainly provides a continuous, uniform, and robust support surface for axial contact with the load-bearing shoulder 146 of the armored load-bearing assembly 140. This design ensures that the axial load is evenly distributed circumferentially in the split-shell 110, avoiding excessive local stress. The semi-annular load-bearing step 118 can be integrally formed with the half-shell or formed through subsequent machining. Its geometry, such as width, height, and corner radius, is optimized according to the expected axial tensile force and the mechanical properties of the shell material to maximize the contact area and minimize stress concentration.

[0058] The load-bearing shoulder 146 is a specially designed structure on the split conical load-bearing seat 141, whose surface directly contacts and supports the surface of the annular load-bearing step in the axial direction. This axial contact structure is the core mechanism for effectively transmitting axial tensile force. When the submarine optical cable 200 is subjected to axial tensile force, the force is first transmitted to the split conical load-bearing seat 141 through the outer armor steel wire 201, and then directly acts on the annular load-bearing step by the load-bearing shoulder 146. This direct axial contact ensures a clear and efficient load transmission path, avoiding the transmission of load through secondary force methods such as shearing or bending, thereby improving the stability and reliability of the structure. To ensure the contact effect, the contact surfaces of the load-bearing shoulder 146 and the annular load-bearing step are usually machined with high precision to ensure good fit and uniform contact pressure.

[0059] The above design clearly defines the complete transmission path of the axial tensile force borne by the submarine optical cable 200 within the junction box. Specifically, the axial tensile force of the submarine optical cable 200 is first borne by its external load-bearing components—the outer armor steel wires 201. These outer armor steel wires 201 are firmly anchored and clamped by the split-type conical load-bearing seats 141. Subsequently, the tension of the outer armor steel wires 201 is effectively gathered and transmitted through the structure of the split-type conical load-bearing seats 141, especially its load-bearing shoulders 146. Finally, the load-bearing shoulders 146 directly transmit this axial tensile force to the annular load-bearing steps inside the split-type box 110. Through this clear and continuous force transmission chain, it is ensured that the axial tensile force of the submarine optical cable 200 can be safely and reliably transmitted from the cable body to the main structure of the junction box, thereby protecting the optical fiber housing assembly 160 and optical fiber connections inside the junction box from the effects of axial stress.

[0060] Through the above technical solution, semi-annular load-bearing steps 118 are respectively provided on the inner walls of the ends of the first half-shell 111 and the second half-shell 112, forming annular load-bearing steps after fastening, and the load-bearing shoulder 146 abuts against the annular load-bearing step axially. This embodiment provides an efficient and reliable axial tensile force transmission mechanism. The mechanism ensures that the huge axial tensile force of the submarine optical cable 200 can be uniformly and stably transmitted to the main structure of the split-type box 110 through the outer armor steel wire 201, the split conical load-bearing seat 141, and the load-bearing shoulder 146. This effectively solves the technical problem of how to reliably transmit the axial tensile force borne by the load-bearing shoulder 146 to the box structure in the split-type box 110 structure, avoiding stress concentration and potential structural failure risks. This design significantly enhances the overall structural strength and tensile strength of the junction box, ensuring long-term stable operation of the submarine optical cable junction box 100 under harsh environments such as high pressure and high tension in the deep sea. It effectively protects the fragile internal optical fiber connections, thereby greatly improving the reliability and service life of the submarine optical cable system.

[0061] Furthermore, to facilitate the description of the circumferential arrangement of the outer armor steel wire 201 and the steel wire positioning groove 143, within the end face section perpendicular to the axis of the submarine optical cable 200, with the central axis of the submarine optical cable 200 as the center O, and the circumference of the center of the steel wire positioning groove 143 as the positioning circle, the radius of the positioning circle is... The direction of the intersection of the joint surfaces of the first half-shell 111 and the second half-shell 112 on one side of the end face section is taken as the zero-degree reference direction, and the counterclockwise direction is taken as the positive direction of the circumferential angle. The center point of the j-th wire positioning groove. The angle formed by the line connecting the center O to the zero-degree reference direction is defined as the circumferential angle. ,in ∈[0, 2π).

[0062] The end face coordinates of the center point of the j-th wire positioning groove can be expressed as:

[0063] in, Let be the lateral coordinate of the center of the j-th wire positioning groove. Let J be the vertical coordinate of the center of the j-th wire positioning groove. The radius of the circumference of the center of the wire positioning groove. Let be the circumferential angle of the j-th wire positioning groove.

[0064] Based on the segmented splicing surface of the split-type conical bearing seat, the positioning pins or positioning grooves, the anti-misalignment protrusions, the joints of the split-type clamping components, and the natural exit angle of the outer armor steel wire, the circumferential arrangement area of ​​the steel wire positioning groove is determined. Among these, the local angle regions corresponding to the segmented splicing surface, the positioning structure, and the joints of the clamping components are designated as prohibited groove-laying angle regions, and the steel wire positioning grooves are arranged outside these prohibited groove-laying angle regions. Prohibited groove-laying angle regions in the calculation of circumferential groove angles. Determined solely by the structure of the split-type conical load-bearing component, it preferably includes a corner avoidance area at the segmented splicing surface. Positioning structures such as positioning pins or positioning grooves avoid corner areas. Separate clamping components, joints, or clamping blind spots, avoiding corner areas. : .

[0065] If the number of wire positioning grooves is N, then the ideal circumferential spacing is Avoiding prohibited corner areas. Under these conditions, the spacing between adjacent circumferential directions can be made as close as possible. This reduces uneven stress on the outer armor steel wire 201. The minimum circumferential spacing can be estimated using the following formula:

[0066] in, The diameter of the outer armor steel wire, This is the minimum assembly gap between the steel wires.

[0067] The outer armor steel wire 201 has a divergence angle when it enters the steel wire positioning groove 143 from the stripping point. Let the radius of the inner cable core after stripping be... The radius of the center circle of the steel wire positioning groove is The axial transition length of the steel wire from the stripping start point to the inlet of the positioning groove is ,but:

[0068] To avoid sharp bends, localized yielding, or fatigue damage to the outer armor steel wire 201, it is preferable to use... The actual bending radius is not less than the preset minimum bending radius. The minimum allowable bending radius, allowable tensile stress, and assembly fatigue test are determined for the outer armor steel wire.

[0069] This embodiment further proposes that the load-bearing shoulder 146 and the annular load-bearing step are in surface contact, and the step width of the annular load-bearing step satisfies the formula: ; in, The width of the ring-shaped load-bearing step. For the load safety factor of the split box 110, The design axial tensile force for the split box 110, The average radius of the semi-circular load-bearing step 118 is given. The allowable contact compressive stress is given by material 110 for the split-type box body.

[0070] Specifically, the load-bearing shoulder 146 and the annular load-bearing step adopt a surface contact, meaning that the two components form a contact surface with a certain area in the contact area, rather than an idealized point contact or line contact. This contact method can effectively distribute the force over a larger area, thereby significantly reducing stress concentration per unit area. In the submarine optical cable junction box 100, the surface contact between the load-bearing shoulder 146 and the annular load-bearing step ensures that the axial tensile force transmitted by the submarine optical cable 200 can be evenly distributed on the annular load-bearing step, avoiding material plastic deformation or fatigue failure caused by local high stress, and improving the load-bearing capacity and service life of the structure.

[0071] At the same time, the step width of the annular load-bearing step satisfies the formula The formula guides the width design of annular load-bearing steps to ensure sufficient strength and safety when subjected to the expected axial tensile force. Among them, The radial dimension of the annular load-bearing step directly affects its load-bearing area. By accurately calculating and controlling the width, it can be ensured that the load-bearing step can effectively distribute and transmit axial loads. This is the load safety factor for the split-type box 110. It is a factor greater than 1 used to consider various uncertainties in the design, such as material property fluctuations, manufacturing tolerances, changes in environmental conditions, and load changes during long-term service. Introducing a safety factor can ensure that the structure remains safe and reliable even under the most unfavorable working conditions, avoiding unexpected failures. It is the maximum axial tensile force that the split-type box 110 may withstand during its service life. It is the basic load for design calculations, and its value is usually determined by a comprehensive evaluation based on factors such as the laying depth of the submarine optical cable, water flow impact, and seabed topography. It is the average radius of the semi-circular load-bearing step 118. This is the geometric parameter of the circular load-bearing step, used to calculate the load-bearing area. In a circular structure, the average radius is a key dimension for determining its perimeter and effective load-bearing area. The maximum allowable stress value of the material used in the split-type box 110 under contact compression is an important indicator of the material's mechanical properties. During design, it is essential to ensure that the actual contact stress does not exceed the allowable value to prevent yielding, fracture, or excessive deformation of the material. Using the formula, the minimum width of the annular load-bearing step can be scientifically determined based on the expected axial tensile force, material properties, and safety requirements, thereby ensuring its structural integrity under extreme loads.

[0072] Through the above technical solution, the load-bearing shoulder 146 and the annular load-bearing step adopt surface contact, effectively avoiding the local stress concentration problem that may be caused by point contact or line contact, so that the axial tensile force of the submarine optical cable 200 can be evenly distributed on the annular load-bearing step. Based on this, a formula for calculating the step width is introduced. And comprehensively considered the load safety factor Design axial tensile force The average radius of the semi-circular load-bearing step 118 and the allowable contact compressive stress of the material of the split box 110 This design ensures that the annular load-bearing steps have sufficient load-bearing capacity and safety margin. This not only effectively prevents material fatigue, plastic deformation, or structural failure caused by stress concentration under high pressure and strong tension in the deep sea, but also significantly improves the structural reliability and durability of the submarine optical cable junction box 100 during long-term service, thereby ensuring the stability and sealing of the optical cable connection and extending the service life of the junction box.

[0073] This embodiment further proposes that the inner wall of the filling and anchoring cavity 131 in the chamber is provided with a plurality of locking grooves arranged at intervals along the axial direction.

[0074] Specifically, the locking groove is a groove structure formed on the inner wall of the potting and anchoring cavity 131 within the chamber. Its main function is to increase the mechanical interlocking force between the sealant and the cavity, preventing the sealant from detaching or shifting due to stress, temperature changes, or other factors after curing or during long-term service. These locking grooves can be designed in various geometries to optimize their locking effect. For example, shapes with barbs or expansion cross-sections, such as dovetail grooves, T-grooves, or stepped grooves, can be used. These shapes allow the cured sealant to form a mechanical anchor within the groove, providing additional pull-out resistance even if the adhesion between the sealant and the cavity material decreases. The locking grooves are spaced apart axially, meaning they are arranged at certain intervals along the length of the cavity, forming a series of mechanical blocking points, thereby providing uniform and effective locking throughout the potting area. This spaced arrangement ensures the stability of the sealant throughout the anchoring cavity, avoiding failure caused by localized stress concentration.

[0075] By providing multiple axially spaced locking grooves on the inner wall of the injection-anchoring cavity 131 within the chamber, this embodiment effectively solves the problem of sealant potentially detaching from the inner wall of the cavity due to long-term stress or environmental changes. These locking grooves form a mechanical interlocking structure with the injected and cured sealant, significantly enhancing the sealant's anchoring ability and pull-out resistance. Even when the submarine optical cable 200 is subjected to significant axial tensile force or undergoes temperature cycling, the locking grooves provide additional mechanical support, ensuring the sealant is firmly fixed inside the cavity. This maintains the sealing integrity of the injection-anchoring cavity 131 within the chamber and the reliable anchoring of the submarine optical cable 200, greatly improving the long-term service reliability of the submarine optical cable splice box 100.

[0076] This embodiment further proposes that the locking groove on the inner wall of the above-mentioned cavity filling and anchoring cavity 131 is one or more of the following: dovetail groove, T-shaped groove and stepped groove.

[0077] Specifically, the dovetail groove has a trapezoidal cross-section, with its opening width smaller than its bottom width, forming a hook-like structure. After the sealant is injected and cured, it completely fills the internal space of the dovetail groove, with the wider bottom portion "locked" by the cavity wall, creating a strong mechanical interlocking effect. This structure effectively resists pull-out or detachment of the sealant under axial or radial forces, significantly enhancing the anchoring strength of the potting compound. The T-groove has a cross-section resembling the letter "T," characterized by wing-like structures extending outwards from both sides of the bottom. After the sealant cures, these wing-like structures are firmly restrained by the cavity wall, forming multi-directional mechanical anchoring. The T-groove not only provides excellent axial pull-out resistance but also resists radial shear forces to a certain extent, further improving the overall stability of the potting compound. The stepped groove's inner wall exhibits a stepped structure with progressively contracting or expanding surfaces. After the sealant is filled and cured, these steps form multiple physical barriers, preventing displacement of the sealant under stress. Stepped grooves effectively disperse stress and improve the creep resistance and long-term anchoring effect of the potting compound by increasing the contact area between the sealant and the cavity wall and forming multiple mechanical constraints. Furthermore, by combining one or more of dovetail grooves, T-grooves, and stepped grooves, the arrangement and combination of locking grooves can be flexibly designed according to specific engineering needs and stress analysis. For example, dovetail grooves can be used more extensively in areas bearing the main axial tensile force, while T-grooves can be introduced in areas where radial stability is also required. Through the synergistic effect of different shapes, more optimized and comprehensive potting and anchoring performance can be achieved.

[0078] This embodiment also proposes the following steps for the assembly and glue injection method: Open the first half-shell 111 and the second half-shell 112, and put the pre-treated submarine optical cable 200 into the second half-shell 112; A split conical bearing seat 141, a split clamping member 144, and a locking member 145 are installed radially so that the outer armor steel wires 201 of the submarine optical cable 200 radiate outward in the end bearing fixing cavity 119 and are respectively placed into the steel wire positioning grooves 143 of the split conical bearing seat 141, pressing the outer armor steel wires 201 and making the bearing shoulder 146 abut against the annular bearing step; Complete the connection between the optical unit 202 and the optical fiber housing assembly 160 of the submarine optical cable 200; The first half-shell 111 and the second half-shell 112 are fastened together, and the locking assembly 116 is locked with a set torque; Vacuum is drawn into the cavity 131 and / or the end cavity 132 through the vacuum hole, and sealant is injected into the cavity 131 and the end cavity 132 through the middle injection hole 115, so that the sealant fills the cavity 131 and the end cavity 132 under the combined action of negative pressure traction and injection pressure.

[0079] The core innovation of this embodiment lies in the active elimination of air bubbles by combining negative pressure vacuuming with injection pressure, and the realization of on-site error-correctable potting operation by combining radial assembly process. This solves the problem of air residue forming water seepage channels in traditional potting, and achieves a highly reliable sealing effect in narrow joint surfaces and closed cavities. Specifically, the method first utilizes the radial assembly characteristics of the split-type housing 110, allowing the submarine optical cable 200, armored load-bearing component 140, and optical fiber housing component 160 to be radially installed, inspected, and corrected while the housing is separated, avoiding the problem of "cutting and redoing" due to missing or incorrectly installed components; secondly, during the potting stage, vacuuming is performed on the potting and anchoring cavity 131 and the end potting and anchoring cavity 132 inside the chamber through the end vacuum hole 120 and the middle vacuum hole 114, forming a negative pressure environment to actively drive out the residual air in the cavity, while sealant is injected through the middle injection hole 115, so that the sealant is evenly filled along the cavity axis under the dual action of negative pressure traction and injection pressure, effectively eliminating hidden water seepage channels.

[0080] Furthermore, the method achieves circumferential load distribution of the outer armor steel wire 201 through the steel wire positioning groove 143 of the split conical bearing seat 141, ensuring that the surface contact between the bearing shoulder 146 and the annular bearing step transmits axial tensile force, thereby decoupling the armor bearing path from the sealing path. Based on this, the dual-cavity structure of the in-cell potting anchoring cavity 131 and the end potting anchoring cavity 132 respectively performs segmented anchoring of the submarine optical cable 200 before and after separation. Combined with the negative pressure assisted filling mechanism, this significantly improves the watertightness and tensile strength in deep-sea environments. Through the above technical solutions, not only is the problem of uneven colloid filling caused by traditional potting relying on manual experience overcome, but the goal of actively eliminating air bubbles in the narrow joint surface and closed injection cavity is also achieved. This provides technical assurance for the long-term service reliability of the submarine optical cable splice box 100 under complex conditions such as water pressure cycling, temperature cycling, and ocean current disturbance.

[0081] This embodiment further proposes that when injecting sealant into the sealing anchor cavity 131 inside the chamber or the end sealing anchor cavity 132, the amount of sealant injected should be controlled according to the following formula: .in, This refers to the glue injection flow rate. This refers to the glue application time. The fill margin coefficient and Greater than 1, The effective volume of the in-cell filling and anchoring cavity 131 or the end filling and anchoring cavity 132.

[0082] Specifically, the technical solution uses a mathematical formula to precisely guide the injection volume of sealant, ensuring that the potting cavity is fully and appropriately filled. This represents the total amount of sealant actually injected during the injection process; it is the injection flow rate. With glue injection time The product of the glue flow rate. This refers to the volume of sealant injected per unit time. In practice, it can be precisely controlled through the settings of the dispensing equipment, such as using a constant flow pump or a dispensing system with a flow sensor to monitor and adjust the flow rate in real time, ensuring that the sealant is injected stably at a preset speed. Dispensing time This refers to the time from the start to the end of sealant injection, a parameter related to the sealant flow rate. These factors collectively determine the total amount of adhesive injected, and the duration of the injection process can be precisely controlled using a timer or automated control system. Fill margin factor It is a coefficient greater than 1, and its function is to determine the effective volume of the potting cavity. Provide a certain amount of excess filling margin. Due to factors such as potential volume shrinkage of the sealant during curing or the presence of micro-air bubbles during filling, directly calculate based on the effective cavity volume. Injecting sealant may result in incomplete final filling. This can be addressed by introducing a sealant concentration greater than 1. This ensures that even with the aforementioned factors, the potting cavity can be completely filled, thus guaranteeing the reliability of the sealant and anchorage. The specific value of the coefficient can be calibrated and optimized based on the characteristics of the sealant, the cavity structure, and actual test results. Effective volume This refers to the actual volume of space available for sealant filling in the sealed anchoring cavity 131 or the end sealed anchoring cavity 132 when they are engaged. The volume can be precisely calculated using 3D modeling software or obtained through actual measurement, water volume method, etc. (Accurate acquisition) It is a prerequisite for controlling the amount of sealant injected, and it provides a benchmark for calculating the total amount of sealant required.

[0083] Through the above technical solution, precise quantitative control of the injection volume can be achieved when injecting sealant into the sealing anchor cavity 131 or the end sealing anchor cavity 132 within the chamber. This is based on a preset injection flow rate. and injection time Combined with the effective volume of the potting cavity and fill margin factor This process ensures that the amount of sealant injected is sufficient to fill the cavity while avoiding excessive overflow. This effectively solves the problems of insufficient filling or excessive overflow that may occur during traditional sealant injection, thus significantly improving the sealing integrity and anchoring reliability of the submarine optical cable splice cassette 100. Precise sealant filling guarantees a tight bond between the outer armor steel wire 201 and the split conical bearing seat 141, as well as between the submarine optical cable 200 and the cavity, enhancing the long-term stability and pull-out resistance of the splice cassette in complex marine environments. Simultaneously, it avoids sealant waste and potential contamination of the optical fiber housing assembly 160, simplifies subsequent cleaning work, and improves production efficiency and product quality.

[0084] In the above-described assembly and sealant injection method, the steps of vacuuming and injecting sealant aim to ensure that the inner potting anchor cavity 131 and the end potting anchor cavity 132 are fully filled with sealant and form a reliable seal. However, in actual operation, the sealant injection process alone cannot completely guarantee the integrity of the seal between the potting cavity and the external environment. For example, minor defects on the snap-fit ​​surface of the box, shrinkage after the sealant cures, or possible micro-air bubbles inside may all lead to incomplete sealing, thereby affecting the long-term reliability of the submarine optical cable splice box 100, and even causing seawater intrusion, threatening the normal operation of the optical cable.

[0085] Therefore, a reliable testing method is needed to verify the sealing performance of the potting area.

[0086] To address this, this embodiment further proposes a step of performing pressure holding tests through a vacuum hole before and / or after the injection of sealant. Specifically, the method sets the initial pressure during the holding time to be... The termination pressure is When satisfied If the sealing and anchoring cavity 131 inside the chamber and its inner and outer sealing boundaries or the sealing and anchoring cavity 132 at the end and its inner and outer sealing boundaries are determined to have good airtightness, then... and These represent the start and end times of the hold time, respectively. The allowable pressure recovery threshold for vacuum holding pressure testing is obtained through calibration.

[0087] The key feature of this technique—performing pressure holding tests via a vacuum port before and / or after sealant injection—lies in utilizing pressure changes to assess sealing performance. Pressure holding testing is a non-destructive method for airtightness testing, assessing the integrity of the seal by monitoring pressure changes within a confined space. Testing before sealant injection allows for the early detection of sealing defects in the potting cavity structure formed after the split-type housing 110 is assembled, such as improper installation of the double-sealant strip structure 150 at the joint surface or micro-cracks in the housing itself. This avoids ineffective sealant injection into defective cavities, saving materials and time. Testing after sealant injection verifies the final sealing effect after sealant curing, ensuring the adhesion and filling integrity between the sealant and components such as the inner wall of the cavity, the outer surface of the submarine optical cable 200, and the armored load-bearing assembly 140, thereby comprehensively evaluating the sealing performance of the entire potting system. During testing, the central vacuum hole 114 on the potting and anchoring cavity 131 and / or the end vacuum hole 120 on the end potting and anchoring cavity 132 can be used to connect the vacuum pump and a high-precision pressure sensor. First, the cavity is evacuated to a preset negative pressure value. Then, the vacuum pump is turned off, and the pressure change inside the cavity is monitored for a certain period of time.

[0088] Regarding the initial pressure during the holding time, let it be... The termination pressure is When the following conditions are met: The technical feature that determines the airtightness of the encapsulated anchoring cavity 131 and its inner and outer sealing boundaries, or the end encapsulated anchoring cavity 132 and its inner and outer sealing boundaries, provides a quantitative and objective judgment standard. During the pressure holding test, if there is a leak in the cavity, external air will enter through the leak point, causing the internal pressure of the cavity to gradually rise. This is achieved by accurately measuring the pressure at a specific holding time. Internal pressure change ( ), and compared it with the preset allowable pressure rebound threshold. By comparing the two, it can be determined whether the airtightness of the cavity meets the requirements. Among them, the inner and outer sealing boundaries refer to the interface between the potted cavity and the external seawater environment, as well as the interface between the potted cavity and internal components such as the submarine optical cable 200 and the optical fiber housing assembly 160, ensuring that there are no leaks at these key interfaces.

[0089] about The allowable pressure rebound threshold for vacuum pressure holding testing is obtained through calibration. This technical characteristic is important in ensuring the scientific validity and reliability of the testing standard. This is not an empirical value or an arbitrarily set value, but rather obtained through a rigorous calibration process. The calibration process typically involves vacuum pressure testing on multiple known qualified samples and multiple known leaking samples, collecting a large amount of pressure recovery data. Through statistical analysis of this data, a value capable of effectively distinguishing between qualified and unqualified products can be determined. Value. For example, the same vacuum pressure, holding time, and testing temperature conditions as the submarine optical cable junction box 100 can be used to test qualified samples and known leaking samples respectively. The mean and standard deviation of the pressure rise of qualified samples, as well as the mean and standard deviation of the pressure rise of leaking samples, can be calculated to determine a reasonable threshold that ensures both product quality and production efficiency. This calibration method based on actual data and statistical analysis enables... It possesses objectivity and repeatability, providing a solid basis for product quality control.

[0090] Through the above technical solution, this embodiment can effectively verify the airtightness of the in-cell encapsulation anchoring cavity 131 and / or the end encapsulation anchoring cavity 132 and their inner and outer sealing boundaries. Testing before sealant injection can promptly identify and correct sealing defects in the box structure itself, avoiding waste during subsequent sealant injection; testing after sealant injection allows for a comprehensive evaluation of the final sealing effect after sealant filling and curing, ensuring the integrity of the entire encapsulation system. This quantitative pressure holding test method avoids potential errors and omissions arising from visual inspection or experience-based judgment alone, significantly reducing the risk of seawater intrusion, thereby greatly improving the long-term reliability and service life of the submarine optical cable junction box 100. In particular, the permissible pressure rebound threshold obtained through calibration... This ensures that the test results are objective and repeatable, providing a reliable and efficient means for the quality control of submarine optical cable junction boxes 100.

[0091] This embodiment further proposes that, during calibration, the same vacuum pressure, pressure holding time, and detection temperature conditions as those for the submarine optical cable junction box 100 are used to perform vacuum pressure holding tests on multiple qualified samples and multiple known leaking samples, thereby obtaining the average pressure recovery amount of the qualified samples. and standard deviation and the average pressure rise of the leaked sample and standard deviation .

[0092] when At that time, the allowable pressure rise threshold The preferred value is one that falls between the two. ,in 1 is the confidence coefficient. Compared with observing the glue discharge through the overflow confirmation hole, this negative pressure assisted glue injection method can reduce glue overflow contamination and actively remove air from the glue injection chamber.

[0093] Specifically, in determining the allowable pressure rebound threshold When calibration is required, it is necessary to conduct a calibration experiment. To ensure the accuracy and representativeness of the calibration results, the calibration experiment should strictly simulate the environmental and operating conditions during actual testing. This means that during the calibration process, parameters such as the vacuum pressure, the duration of pressure holding, and the ambient temperature should be consistent with the conditions used in the actual airtightness test of the submarine optical cable junction box 100. For example, if the actual testing vacuum pressure is set to -0.08 MPa, the pressure holding time is 30 minutes, and the testing temperature is 25℃, then the calibration experiment should also be conducted under these identical conditions. This consistency ensures that the threshold obtained from the calibration can truly reflect the sealing performance of the junction box under actual operating conditions.

[0094] To comprehensively understand the characteristics of pressure recovery under different sealing conditions, the calibration process requires testing two types of samples with clearly defined sealing conditions: one type consists of qualified samples whose sealing performance has been rigorously verified, and the other type consists of known leak samples with clearly defined leak points, either artificially created or naturally formed. By performing vacuum pressure holding tests on a sufficient number of these two types of samples, a large amount of data on pressure recovery under normal sealing and leaking conditions can be collected. This data forms the basis for subsequent statistical analysis, used to distinguish between qualified and unqualified sealing conditions.

[0095] After performing a vacuum pressure test on qualified samples, a series of pressure recovery data will be obtained. By statistically analyzing this data, the average pressure recovery of qualified samples can be calculated. and standard deviation Mean This represents the typical level of pressure recovery for qualified samples under specific testing conditions, while the standard deviation... This reflects the fluctuation range or dispersion of the pressure recovery of qualified samples. These two statistics together depict the distribution characteristics of pressure recovery under normal sealing conditions, providing a quantitative basis for determining the qualified range.

[0096] Similarly, after performing a vacuum pressure test on a known leaking sample, a series of pressure recovery data will be obtained. By statistically analyzing these data, the average pressure recovery of the leaking sample can be calculated. and standard deviation Mean This represents the typical level of pressure recovery in a leaking sample under specific testing conditions, and is usually significantly higher than the mean of a qualified sample. Standard deviation This reflects the fluctuation range of the pressure recovery in the leaked sample. These statistics help to understand the characteristics of pressure recovery under leak conditions and provide data support for distinguishing between leaking and non-leaking conditions.

[0097] Using the above technical solution, the allowable pressure rebound threshold is determined during vacuum pressure holding testing. These values ​​are no longer empirical or arbitrarily set, but rather the result of scientific statistical analysis based on a large amount of actual test data. By conducting thorough tests on qualified and known leaking samples under the same conditions as actual tests and obtaining the mean and standard deviation of their pressure recovery, the distribution characteristics of pressure recovery under normal sealing and leaking conditions can be accurately depicted. Based on this, an optimal value can be determined according to statistical principles, such as by setting confidence intervals or using statistical hypothesis testing methods. This value minimizes the false positive rate. This significantly improves the accuracy and reliability of airtightness testing, effectively avoiding missed detections or false positives caused by improper threshold settings, thereby ensuring the sealing integrity and reliability of the submarine optical cable junction box 100 during long-term service and reducing the risk of failure caused by seal failure.

[0098] The following example will provide a more detailed explanation of the above technical solution: First, the operators open the first half-shell 111 and the second half-shell 112 of the submarine optical cable splice box 100. Due to its split-type box structure 110, the optical cable 200 does not need to be threaded through one end, but can be directly placed radially into the second half-shell 112. This significantly simplifies on-site operations, avoids the risk of "cutting the cable and redoing," and allows for visual inspection and correction of each component during assembly.

[0099] Next, the submarine optical cable 200 is pre-treated by separating its outer armor steel wires 201. Then, the armored load-bearing assembly 140 is installed radially. The assembly includes a split conical load-bearing seat 141, a split clamping member 144, and a locking member 145. The split conical load-bearing seat 141 is formed by at least two conical segments 142 radially interlocked, and its outer circumference is provided with multiple steel wire positioning grooves 143. The operator evenly distributes the outer armor steel wires 201 of the submarine optical cable 200 circumferentially within the end load-bearing fixing cavity 119 and places them into the steel wire positioning grooves 143 of the split conical load-bearing seat 141. Subsequently, the split clamping member 144 is positioned on the outside of the outer armor steel wires 201, and the locking member 145 presses the outer armor steel wires 201 tightly onto the split conical load-bearing seat 141. This radial installation method allows the armored load-bearing component 140 to be easily installed on the laid optical cable and ensures that the outer armor steel wire 201 is subjected to uniform force, avoiding the off-center load failure that may be caused by traditional wedges or inner clamps.

[0100] The split-type conical load-bearing seat 141 also has a load-bearing shoulder 146. When the first half-shell 111 and the second half-shell 112 are engaged, the annular load-bearing step (composed of a semi-annular load-bearing step 118) formed by the inner walls of their ends abuts against the load-bearing shoulder 146 axially. The axial tension of the submarine optical cable 200 is transmitted to the split-type box 110 through the outer armor steel wire 201, the split-type conical load-bearing seat 141, and the load-bearing shoulder 146. The load-bearing shoulder 146 and the annular load-bearing step are in surface contact, and the step width of the annular load-bearing step is precisely designed to meet the requirements of a specific formula, ensuring that the allowable contact compressive stress of the split-type box 110 material will not exceed the limit in the high-tensile environment of the deep sea, thereby ensuring the long-term axial load-bearing stability of the junction box. This design of decoupling the load-bearing path from the sealing path avoids the problem of mutual interference between load-bearing and sealing in traditional structures.

[0101] After the installation of the armored load-bearing component 140 is completed, the operators connect the optical unit 202 of the submarine optical cable 200 to the optical fiber housing component 160 and house the optical fiber housing component 160 in the main housing cavity 113.

[0102] Subsequently, the first half-shell 111 and the second half-shell 112 are fastened together and locked to a set torque by the locking assembly 116. At the mating surface of the first half-shell 111 and the second half-shell 112, a double-sealing strip structure 150 is provided, including an inner sealing strip and an outer sealing strip. This double-sealing design provides higher watertightness for the junction box, effectively resisting the peeling of the sealing interface or the opening of the mating surface caused by the high water pressure and temperature cycling in the deep sea.

[0103] Next is the potting and sealing process. The end potting and anchoring cavity 132 is located on the side of the armored load-bearing assembly 140 closest to the external seawater, used to accommodate and cover the submarine optical cable 200 before the outer armor steel wire 201 is separated. The inner potting and anchoring cavity 131 is located on the side of the armored load-bearing assembly 140 closest to the main receiving cavity 113, used to accommodate and cover the submarine optical cable 200 after the outer armor steel wire 201 is separated. The end potting and anchoring cavity 132 has an end vacuum hole 120, and the inner potting and anchoring cavity 131 has a central glue injection hole 115 and a central vacuum hole 114.

[0104] Before injecting the sealant, the potting anchor cavity 131 and / or the end potting anchor cavity 132 inside the chamber are evacuated through the vacuum port. After evacuation, a pressure holding test is performed. By monitoring whether the pressure rise during the holding time is less than the allowable pressure rise threshold, it is determined whether the cavity and its inner and outer sealing boundaries have good airtightness. This effectively avoids the problem of hidden water seepage channels formed due to residual air or partial incomplete filling in the cavity in traditional potting.

[0105] After confirming good airtightness, sealant is injected into the inner potting and anchoring cavity 131 and the end potting and anchoring cavity 132 through the central injection hole 115. Under the combined action of negative pressure traction and injection pressure, the sealant can fully fill the two cavities, ensuring no air bubbles or voids. The injection volume is strictly controlled according to the formula to ensure sufficient filling and avoid under-filling. The inner wall of the inner potting and anchoring cavity 131 is also provided with multiple locking grooves arranged axially at intervals, such as dovetail grooves, T-shaped grooves, or stepped grooves. These locking grooves enhance the mechanical anchoring effect between the sealant and the inner wall of the box, further improving the reliability of the potting seal and preventing the sealant from peeling off during long-term service.

[0106] Through the synergistic effect of the above series of technical features, the submarine optical cable junction box achieves the convenience of radial assembly, the load-bearing capacity of circumferential load distribution, the decoupling structure of load-bearing and sealing, the guarantee of double sealing, and the potting quality control of negative pressure assisted filling detection. This effectively solves the problems of assembly difficulties, load-bearing failure, and unreliable sealing faced by existing submarine optical cable junction boxes in long-term deep-sea service, and significantly improves the long-term stability of submarine communication links and the reliability of on-site assembly.

[0107] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A submarine optical cable junction box, characterized in that, include: The split-type housing (110) includes a first half-shell (111) and a second half-shell (112); the first half-shell (111) and the second half-shell (112) are fastened together to form a main receiving cavity (113), and an end bearing fixing cavity (119), an end potting anchoring cavity (132), and an in-cell potting anchoring cavity (131) are respectively formed at both ends of the axial direction; the main receiving cavity (113) is used to accommodate the optical fiber housing assembly (160); the end potting anchoring cavity (132) is provided with an end vacuum hole (120); the in-cell potting anchoring cavity (131) is provided with a central glue injection hole (115) and a central vacuum hole (114). The armored load-bearing assembly (140) includes a split conical load-bearing base (141), a split clamping member (144), and a locking member (145). The outer periphery of the split conical load-bearing base (141) is provided with multiple steel wire positioning grooves (143). The outer armor steel wires (201) of the submarine optical cable (200) radiate outward in the end load-bearing fixing cavity (119) and are respectively placed into the steel wire positioning grooves (143). The split clamping member (144) is located outside the outer armor steel wires (201), and the locking member (145) causes the split clamping member (144) to press the outer armor steel wires (201) tightly against the split conical load-bearing base (141). The end-filled anchoring cavity (132) is located on the side of the armored load-bearing component (140) near the external seawater, and is used to accommodate and cover the submarine optical cable (200) before the outer armor steel wire (201) is separated. The in-cell filling and anchoring cavity (131) is located on the side of the armored load-bearing assembly (140) near the main receiving cavity (113) and is used to receive and cover the submarine optical cable (200) after the outer armor steel wire (201) is separated. When the first half-shell (111) is separated from the second half-shell (112), the submarine optical cable (200), the armored load-bearing assembly (140) and the optical fiber housing assembly (160) can be installed radially.

2. The submarine optical cable junction box according to claim 1, characterized in that, The first half-shell (111) and the second half-shell (112) are provided with a double sealing strip structure (150); the double sealing strip structure (150) includes an inner sealing strip and an outer sealing strip.

3. The submarine optical cable junction box according to claim 1, characterized in that, The split conical bearing seat (141) includes at least two conical segments (142) that can be radially engaged; the outer periphery of the conical segments (142) is provided with a plurality of steel wire positioning grooves (143).

4. The submarine optical cable junction box according to claim 1, characterized in that, The split conical bearing seat (141) is provided with a bearing shoulder (146).

5. The submarine optical cable junction box according to claim 4, characterized in that, The inner walls of the ends of the first half-shell (111) and the second half-shell (112) are respectively provided with semi-annular load-bearing steps (118), which are fastened together to form annular load-bearing steps; the load-bearing shoulder (146) abuts against the annular load-bearing steps along the axial direction, so that the axial tension of the submarine optical cable (200) is transmitted to the split box (110) through the outer armor steel wire (201), the split conical load-bearing seat (141), the load-bearing shoulder (146) and the annular load-bearing steps.

6. The submarine optical cable junction box according to claim 5, characterized in that, The load-bearing shoulder (146) and the annular load-bearing step are in surface contact, and the step width of the annular load-bearing step satisfies the following formula: ； in, The width of the ring-shaped load-bearing step. For the load safety factor of the split box (110), For the design axial tensile force of the split box (110), The average radius of the semi-circular load-bearing step (118) is... The allowable contact compressive stress is given to the material of the split box (110).

7. The submarine optical cable junction box according to claim 1, characterized in that, The inner wall of the cavity for filling and anchoring (131) is provided with multiple locking grooves arranged at intervals along the axial direction.

8. An assembly glue injection method, characterized in that, Assembling the submarine optical cable junction box as described in any one of claims 1-7 includes the following steps: Open the first half-shell (111) and the second half-shell (112), and put the pre-treated submarine optical cable (200) into the second half-shell (112). Install the split conical bearing seat (141), split clamping member (144), and locking member (145) radially so that the outer armor steel wire (201) of the submarine optical cable (200) radiates outward in the end bearing fixing cavity (119) and is respectively placed into the steel wire positioning groove (143) of the split conical bearing seat (141), pressing the outer armor steel wire (201) and making the bearing shoulder abut against the annular bearing step; Complete the connection of the optical unit (202) and the optical fiber housing assembly (160) of the submarine optical cable (200); The first half-shell (111) and the second half-shell (112) are fastened together, and the locking assembly (116) is locked with a set torque. Vacuum is drawn into the cavity-filled anchoring cavity (131) and / or the end-filled anchoring cavity (132) through the vacuum hole, and sealant is injected into the cavity-filled anchoring cavity (131) and the end-filled anchoring cavity (132) through the middle injection hole (115), so that the sealant fills the cavity-filled anchoring cavity (131) and the end-filled anchoring cavity (132) under the combined action of negative pressure traction and injection pressure.

9. The assembly and dispensing method according to claim 8, characterized in that, When injecting sealant into the anchoring cavity (131) inside the chamber or the end anchoring cavity (132), the amount of sealant injected shall be controlled according to the following formula: ； in, This refers to the glue injection flow rate. This refers to the glue application time. The fill margin coefficient and Greater than 1, The effective volume of the in-cell filling and anchoring cavity (131) or the end filling and anchoring cavity (132).

10. The assembly and dispensing method according to claim 9, characterized in that, The process also includes the following steps: performing a pressure holding test through a vacuum hole before and / or after injecting the sealant; assuming the initial pressure during the holding time is... The termination pressure is When the following conditions are met: If the gas-filled anchoring cavity (131) and its inner and outer sealing boundaries or the end gas-filled anchoring cavity (132) and its inner and outer sealing boundaries are determined to have good airtightness, then the gas-filled anchoring cavity (131) and its inner and outer sealing boundaries are determined to have good airtightness. and These represent the start and end times of the hold time, respectively. The allowable pressure recovery threshold for vacuum holding pressure testing is obtained through calibration.

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