A cable through-hull sealing device based on temperature-induced volume setting and water pressure self-tightening

Abstract

The application discloses a kind of cable wear sheathing outer sealing device based on temperature-induced constant volume and water pressure self-tightening, it is related to the technical field of ship sealing, the device includes cup-shaped pipe section fixed to ship body plate and cable passing through it. From outside to inside, the outer end is successively equipped with outer pressure nut, outer first compression gasket, temperature-induced constant volume sealing assembly and outer second compression gasket. Temperature-induced constant volume sealing assembly is composed of carbon fiber packing and positive and negative thermal expansion composite material, used to resist extreme cold shrinkage and provide rigid support for the upper; water pressure self-tightening sealing layer adopts elastomer material with dynamic crosslinking network, radial expansion when high-pressure water flow shear force is encountered. The application effectively solves the sealing failure problem caused by cold shrinkage and high pressure in polar deep sea environment through the mechanical cooperation of hard skeleton resisting temperature change and soft gel blocking micro-cracks with water pressure, significantly improves the sealing reliability under extreme conditions.

Description

Technical Field

[0001] This invention relates to the technical field of ship sealing, and more specifically, to an external cable sealing device based on temperature-induced constant volume and water pressure self-tightening. Background Technology

[0002] In ship and marine engineering structures, cables need to extend from inside the hull to the outside (for powering equipment such as underwater lights, sonar, and propulsion systems). This typically requires openings in the hull plating and the installation of through-holes. The sealing performance of this area directly affects the ship's navigational safety and watertight integrity. Currently, traditional methods for sealing cables extending beyond the hull primarily employ stuffing box structures, filled with conventional organic sealants (such as epoxy resin and polyurethane) or modular rubber sealing blocks.

[0003] However, as marine engineering extends into polar and deep-sea areas, the cable penetration points of equipment such as deep-sea submersibles and polar icebreakers face extremely harsh multi-physics environments, including extremely low temperatures (e.g., -25°C), ultra-high alternating water pressure, and continuous high-frequency vibrations. Under these extreme conditions, existing conventional sealing technologies reveal fatal flaws:

[0004] Traditional rubber or resin materials undergo significant volume shrinkage and become brittle at extremely low temperatures, resulting in micron-sized "thermosensitive gaps" between the seal and the cable sheath or metal pipe wall. In shallow water, these tiny gaps may not immediately cause large-scale leakage; however, in the ultra-high water pressure environment of the deep sea, high-pressure seawater can instantly cut into these tiny gaps, tearing the entire sealing layer and causing complete seal failure.

[0005] Existing solutions either rely solely on increasing preload to resist high water pressure or simply on replacing materials with cold-resistant ones to resist low temperatures. However, under the combined effects of cold contraction, high pressure, and vibration, purely cold-resistant materials are too rigid to absorb the microcracks at the interface caused by vibration; while purely pressure-resistant soft rubber shrinks in volume at low temperatures, losing its pressure-resistant foundation. Current technology lacks a solution that can deeply couple temperature compensation with adaptive water pressure fastening to the mechanical structure. Summary of the Invention

[0006] The purpose of this invention is to provide a cable-through-the-hull sealing device based on temperature-induced constant volume and water pressure self-tightening, so as to solve the technical problem that the traditional single sealing structure is prone to micro gaps and high-pressure leakage due to the simultaneous occurrence of extreme cold contraction, high-frequency vibration and ultra-high water pressure in extreme environments such as polar deep sea.

[0007] The technical solution of this invention is: to provide a cable insertion sealing device based on temperature-induced constant volume and water pressure self-tightening, the device comprising:

[0008] Cup-shaped pipe sections fixed at the openings in the hull plates, and cables axially passing through the cup-shaped pipe sections;

[0009] Divided by the hull plating, the cup-shaped tube section is divided into an inner end and an outer end;

[0010] The outer end of the cabin is equipped with an outer clamping nut, an outer first clamping washer, a temperature-induced constant volume sealing assembly, and an outer second clamping washer, which are coaxially assembled from the outside to the inside.

[0011] Apply a self-tightening water pressure sealing layer between the external clamping nut and the cable.

[0012] The temperature-dependent constant volume sealing assembly consists of a carbon fiber packing skeleton and positive and negative thermal expansion composite materials cured in situ within the skeleton gaps. The positive and negative thermal expansion composite materials are composed of a positive thermal expansion elastic substrate and a negative thermal expansion filler, which are used to maintain a constant volume under alternating temperature conditions and provide axial rigid support for the upper end water pressure self-tightening sealing layer.

[0013] A bottom water pressure self-tightening sealing layer is applied between the cable and the cup-shaped pipe section located at the hull plate location;

[0014] Both the end and bottom water pressure self-tightening sealing layers use water pressure self-tightening sealant, which is an elastomer material with a dynamic cross-linked network. When subjected to the fluid shear force generated by the intrusion of external high-pressure seawater, its dynamic cross-linked network reorganizes and generates volume expansion perpendicular to the shear force direction to tighten the cable.

[0015] In any of the above technical solutions, a 0.5 to 2 mm thick interface water pressure self-tightening coating is further applied between the temperature-induced constant volume sealing component and the outer wall of the cable, and between the temperature-induced constant volume sealing component and the inner wall of the cup-shaped pipe section; the material of the interface water pressure self-tightening coating is the same as that of the end water pressure self-tightening sealing layer.

[0016] In any of the above technical solutions, further, from the side near the hull plate towards the inside of the compartment, a first compression washer, a first sealing ring, a second compression washer, a second sealing ring, and a third compression washer are sequentially arranged coaxially; a compression nut is screwed into the opening of the cup-shaped pipe section at the inside of the compartment, and the compression nut is used to press against the third compression washer to force the two sealing rings to expand radially.

[0017] A positive and negative thermal expansion composite material adapted to the cable through-board sealing device based on temperature-induced constant volume and water pressure self-tightening in any of the above technical solutions is also provided. The composite material includes: a positive thermal expansion elastic substrate, a negative thermal expansion filler and a coupling agent.

[0018] The volume ratio of the positive thermal expansion elastic substrate to the negative thermal expansion filler is 65-75:25-35; the mass of the coupling agent is 1% to 3%.

[0019] The coupling agent is a titanate coupling agent.

[0020] In any of the above technical solutions, the positive thermal expansion elastic substrate is further defined as a polyurethane elastomer;

[0021] The coefficient of thermal expansion of polyurethane elastomer is 120 ppm / ℃.

[0022] In any of the above technical solutions, the negative thermal expansion filler is further defined as zirconium tungstate micro powder;

[0023] The particle size of zirconium tungstate powder is 1 to 10 micrometers, and the coefficient of thermal expansion is -9 ppm / ℃.

[0024] The beneficial effects of this invention are:

[0025] This invention incorporates a temperature-dependent volumetric sealing assembly in the core area at the outer end of the cabin, constructed from carbon fiber packing and a composite material of positive and negative thermal expansion (polyurethane and zirconium tungstate). This assembly maintains an absolutely constant volume over a wide temperature range of -25°C to 65°C. Given its underwater application, this material effectively eliminates the gaps caused by material contraction in extremely cold environments. Furthermore, the hardened columnar structure formed after curing provides axial rigidity support for the self-tightening water pressure sealing layer at the upper end, ensuring that external seawater pressure is converted into radial sealing force.

[0026] To address the potential for debonding cracks caused by high-frequency vibrations in ships between rigid, ductile components and cables, this invention incorporates a water-pressure self-tightening sealant at the ends, bottom, and interface. When high-pressure seawater attempts to penetrate along the microcracks, the sealant undergoes volume expansion perpendicular to the shear direction under the triggering of fluid shear force. The higher the water pressure, the stronger the expansion and clamping force, achieving dynamic self-healing sealing of the microcracks. Attached Figure Description

[0027] The advantages of the above and additional aspects of the present invention will become apparent and readily understood in the description of the embodiments in conjunction with the following drawings, wherein:

[0028] Figure 1 This is a schematic flowchart of a cable-through-the-ship sealing device based on temperature-induced constant volume and water pressure self-tightening according to an embodiment of the present invention.

[0029] Among them, 1-cable, 2-cup-shaped pipe section, 3-hull plate, 4-external clamping nut, 5-end water pressure self-tightening sealing layer, 6-external first clamping washer, 7-temperature-induced constant-volume sealing assembly, 8-external second clamping washer, 9-bottom water pressure self-tightening sealing layer, 10-internal first clamping washer, 11-internal first sealing ring, 12-internal second clamping washer, 13-internal second sealing ring, 14-internal third clamping washer, 15-internal clamping nut, 16-interface water pressure self-tightening coating. Detailed Implementation

[0030] To better understand the above-mentioned objectives, features, and advantages of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments of the present invention and the features thereof can be combined with each other.

[0031] In the following description, many specific details are set forth in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and therefore the scope of protection of the invention is not limited to the specific embodiments disclosed below.

[0032] like Figure 1 As shown, this embodiment provides a cable penetration sealing device based on temperature-induced constant volume and water pressure self-tightening. The device is constructed entirely from a cup-shaped tube section 2 fixed at an opening in the hull plate 3. The cup-shaped tube section 2 is a hollow, stepped metal rotating body, watertightly fixed to the hull plate 3 by rigid connections such as welding. The cable 1 passes through the internal through-channel of the cup-shaped tube section 2 axially. Taking the plane where the hull plate 3 is located as the boundary, the cup-shaped tube section 2 is spatially divided into an external end exposed to the external seawater environment and an internal end located inside the hull. The core of this invention lies in the multi-stage series composite sealing architecture constructed at the external end and the axial force transmission basic sealing architecture set at the internal end.

[0033] First, the complex mechanical seal structure at the outer end of the compartment is described in detail. At the outer end of the cup-shaped tube section 2, the inner wall is machined with a receiving cavity and internal threads for assembly. From the outermost side (outer end) to the inner side (near the hull plate 3), the following components are coaxially assembled in sequence: outer end clamping nut 4, end water pressure self-tightening sealing layer 5, outer first clamping washer 6, temperature-induced constant volume sealing assembly 7, outer second clamping washer 8, and bottom water pressure self-tightening sealing layer 9.

[0034] Specifically, the external clamping nut 4 is a stepped flange with a central through hole, and its outer circumferential surface is provided with external threads. It is fixed to the outermost opening of the outer end of the cup-shaped pipe section 2 by threaded connection. A first annular pressure cavity is formed by the lower end face of the external clamping nut 4, the inner wall of the cup-shaped pipe section 2, the outer sheath surface of the cable 1, and the upper end face of the first external clamping washer 6 below. The first annular pressure cavity is densely filled with an end water pressure self-tightening sealing layer 5. Right below the end water pressure self-tightening sealing layer 5, a metal annular first external clamping washer 6 is coaxially sleeved. The inner diameter of the washer is slightly larger than the outer diameter of the cable 1, and the outer diameter is clearance-fitted with the inner diameter of the cup-shaped pipe section 2, which serves to isolate and uniformly transmit axial force.

[0035] A temperature-dependent volumetric sealing assembly 7 is installed between the lower end face of the first external compression washer 6 and the upper end face of the second external compression washer 8 below it. Structurally, the temperature-dependent volumetric sealing assembly 7 uses carbon fiber packing as a three-dimensional pressure-resistant skeleton, with the carbon fiber packing being densely wound in multiple layers along the circumference of the cable 1. At the same time, positive and negative thermal expansion composite materials are in-situ injection molded and cured to fill the micro-grid gaps formed by the interwoven carbon fiber packing, thereby forming a composite columnar body that combines macroscopic rigid support with microscopic volumetric constant properties.

[0036] The core function of the positive and negative thermal expansion composite material filling the internal cavity of the temperature-dependent constant-volume sealing component 7 is to counteract thermal expansion and contraction in a wide temperature range from -25°C to 65°C, thereby achieving absolute constant volume of the columnar body. This composite material is composed of a positive thermal expansion elastic substrate and a negative thermal expansion filler.

[0037] The effective thermal expansion coefficient of the composite material satisfies the following relationship:

[0038] ;

[0039] In the formula, The effective thermal expansion coefficient of the composite material; , These are the coefficients of thermal expansion of the substrate and the filler, respectively. , These are the volume fractions of the substrate and the filler, respectively. , These are the elastic moduli of the substrate and the filler, respectively.

[0040] To achieve the technical objective, it is necessary to optimize the formulation so that the total thermal expansion coefficient of the composite material approaches zero. Considering the necessity of using this material in conjunction with a water-pressure self-tightening sealant, the following multiple examples and comparative examples were prepared and subjected to uniform simulated environmental testing.

[0041] Example 1:

[0042] In this embodiment, a certain brand of polyurethane elastomer (thermal expansion coefficient 120ppm / ℃, elastic modulus 50MPa) and zirconium tungstate micropowder (thermal expansion coefficient -9ppm / ℃, elastic modulus 68GPa) were selected. Based on the effective thermal expansion coefficient formula provided by this invention, to make the total thermal expansion coefficient of the composite material approach zero, the formula was calculated and rounded to determine: 70% polyurethane elastomer by volume and 30% zirconium tungstate micropowder by volume.

[0043] Preparation process: Zirconium tungstate micro powder is dried at 120℃, and 2% titanate coupling agent is added to modify the surface. Then it is mixed with polyurethane prepolymer under vacuum to remove bubbles, injected into the pre-wound carbon fiber packing skeleton, and allowed to stand and cure in situ to form a temperature-induced constant volume sealing component.

[0044] Example 2:

[0045] Bisphenol A type epoxy resin (coefficient of thermal expansion 60 ppm / ℃, elastic modulus 3 GPa) was selected as the positive thermal expansion elastic matrix. Due to the high elastic modulus of epoxy resin, the proportion of negative thermal expansion filler must be increased to achieve zero expansion. Based on calculations, the formulation was adjusted compared to Example 1 as follows: epoxy resin volume fraction 55%, zirconium tungstate micropowder volume fraction 45%, and 2% titanate coupling agent added, with all other conditions remaining the same as in Example 1.

[0046] Example 3:

[0047] Silicone rubber (coefficient of thermal expansion 150 ppm / ℃, elastic modulus 5 MPa) was selected as the positive thermal expansion elastic substrate. Due to the high coefficient of thermal expansion and low modulus of silicone rubber, the formulation was adjusted compared to Example 1 based on the formula calculation as follows: silicone rubber volume fraction 75%, zirconium tungstate micro powder volume fraction 25%, 2% titanate coupling agent added, and the remaining conditions were kept the same as in Example 1.

[0048] Example 4:

[0049] Fluororubber (coefficient of thermal expansion 100ppm / ℃, elastic modulus 10MPa) was selected as the positive thermal expansion elastic substrate. Based on the formula calculation, the formulation was adjusted compared to Example 1 as follows: 68% fluororubber by volume, 32% zirconium tungstate micropowder by volume, and 2% titanate coupling agent added, with the remaining conditions consistent with Example 1.

[0050] The sealing components prepared in Examples 1 to 4 were assembled into laboratory high-pressure simulated sealing test benches (with a solid simulated cable running through the center). The test benches were placed in a high-low temperature alternating chamber and subjected to temperature cycling from -20°C to 50°C; simultaneously, a hydrostatic pressure of 5.0 MPa was applied in the high-pressure water chamber, and continuous lateral vibration at 50 Hz and an amplitude of 2 mm was applied on an electromagnetic vibration table. The time to significant leakage in the normal pressure observation chamber for each group of samples was recorded over three weeks (500 hours), and their volume change rate was measured.

[0051] In terms of test results, all four examples performed well in terms of volume change rate, which were 0.12%, 0.08%, 0.15%, and 0.14% respectively, consistent with the theory. However, in the leakage test, only Example 1 did not show significant leakage after 500 hours, while Examples 2, 3, and 4 showed significant leakage at the 187th, 354th, and 271st hours of the test, respectively.

[0052] Observations of the tested materials revealed that: Example 2 exhibited cleavage cracks, presumably due to the excessively high elastic modulus of its synthetic material, which made the material more brittle overall. Under long-term high-frequency vibration, it could not effectively absorb vibration stress, eventually resulting in microcracks and leakage; Example 3 showed local fatigue deformation; while Example 4 showed obvious fatigue debonding at the interface.

[0053] Ultimately, the material selection adopted the scheme of Example 1. The positive thermal expansion elastic substrate was selected as a polyurethane elastomer with a volume fraction of 65% to 75% and a coefficient of thermal expansion of approximately 120 ppm / ℃; the negative thermal expansion filler was selected as zirconium tungstate micropowder with a volume fraction of 25% to 35% and a coefficient of thermal expansion of approximately -9 ppm / ℃, with a particle size controlled between 1 and 10 micrometers; 1% to 3% of titanate coupling agent by weight of the filler was added to improve the interfacial bonding between the inorganic filler and the organic substrate. In terms of the preparation process, the zirconium tungstate micropowder was first dried at 100 to 120℃ for 2 hours and then mixed and modified with the coupling agent in a high-speed mixer. Subsequently, the modified powder was mixed and degassed with polyurethane prepolymer under vacuum conditions, and finally injected into the carbon fiber packing skeleton for in-situ curing to form a complete temperature-induced volumetric sealing component 7.

[0054] Below the temperature-induced constant-volume sealing assembly 7, a second external compression washer 8 is coaxially fitted, serving as the bottom rigid support surface of the assembly. A second annular pressure-bearing cavity is formed between the lower end face of the second external compression washer 8 and the reduced-diameter step (base) inside the outer end of the cup-shaped tube section 2, and this cavity is filled with a bottom water pressure self-tightening sealing layer 9. Furthermore, to compensate for microscopic fit defects between the rigid frame and the flexible cable, an interface water pressure self-tightening coating 16 with a thickness of 0.5 to 2 mm is uniformly applied to the minute assembly gaps between the inner wall of the temperature-induced constant-volume sealing assembly 7 and the outer sheath of the cable 1, and between its outer cylindrical surface and the inner wall of the cup-shaped tube section 2.

[0055] The aforementioned end water pressure self-tightening sealing layer 5, bottom water pressure self-tightening sealing layer 9, and interface water pressure self-tightening coating 16 all employ water pressure self-tightening sealant. Water pressure self-tightening sealant is an elastomer material with a dynamic cross-linked network. When subjected to the fluid shear force generated by the intrusion of external high-pressure seawater, its internal network reorganizes and generates volume expansion perpendicular to the shear force direction to tighten the cable. In this embodiment, the adhesive material is copolymerized from 60 to 80 parts by weight of thiourea acrylate monomer, 10 to 20 parts by weight of mercapto crosslinking agent, and 1 to 3 parts by weight of initiator. Its mechanical properties are as follows: under static, pressureless conditions, it is a plastic gel; when subjected to the fluid shear force generated by the intrusion of external high-pressure seawater, its internal polar hydrophobic hydrogen bond network undergoes reversible reorganization, and the molecular chains change from coiled to extended, thereby generating macroscopic volume expansion perpendicular to the shear force direction.

[0056] Next, the sealing structure at the inner end of the compartment will be described in detail. At the inner end of the cup-shaped tube section 2, a receiving cavity is also machined into its inner bore. Starting from the inner stepped surface near the hull plate 3, a first inner-compression washer 10, a first inner-compression sealing ring 11, a second inner-compression washer 12, a second inner-compression sealing ring 13, and a third inner-compression washer 14 are sequentially and coaxially fitted inwards towards the compartment. Finally, an inner-compression nut 15 is screwed into the internal thread of the inner end of the cup-shaped tube section 2 via its external thread for overall axial compression. The inclusion of the third inner-compression washer 14 effectively prevents the inner-compression nut 15 from generating destructive rotational shear force on the second inner-compression sealing ring 13 below during the rotational tightening process. When the internal clamping nut 15 is tightened, the resulting axial preload is transmitted downward through the three metal clamping washers in sequence, forcing the two sealing rings sandwiched in the middle to undergo axial compression and radial expansion, so that their outer circumferential surfaces tightly fit the inner wall of the cup-shaped pipe section 2, and their inner circumferential surfaces tightly grip the outer wall of the cable 1, thereby forming a double-base physical seal on the inner side of the compartment.

[0057] In this invention, the temperature-induced constant-volume sealing component 7 and the water pressure self-tightening sealant form a tight synergistic defense line in terms of physical structure and mechanical transmission. The synergistic principle is as follows:

[0058] In the extreme environment of the deep sea, the equipment simultaneously faces severe temperature changes, high-frequency vibrations, and ultra-high water pressure. The temperature-dependent constant-volume sealing component 7 solves the macroscopic problem of cold shrinkage, ensuring that the main structure inside the sealed cavity does not collapse or shrink in volume at temperatures ranging from -25°C to 65°C. However, because the material of this constant-volume component is relatively hard after curing in order to maintain a constant volume, micron-level transient gaps can easily form at the interface between it and the cable 1 during severe vibrations of the ship. At this time, the water pressure self-tightening sealant plays a crucial microscopic compensating role. When high-pressure seawater attempts to penetrate through the gap of the external clamping nut 4, it first squeezes the end water pressure self-tightening sealing layer 5; because the hard and volume-constant temperature-dependent constant-volume sealing component 7 acts as a rigid anvil, the end water pressure self-tightening sealing layer 5 has nowhere to retreat after being compressed, and can only convert the axial pressure of the seawater into a strong radial expansion force, tightly gripping the cable 1. If even a trace amount of water seeps into the gap between the temperature-controlled volumetric sealing component 7 and the cable 1, accompanied by vibration, the interface water pressure self-tightening coating 16 applied at this location will instantly undergo microscopic volume expansion upon contact with the water flow shear force, automatically sealing the micro-cracks caused by vibration. Even if seawater penetrates the entire volumetric component to the bottom, the bottom water pressure self-tightening sealing layer 9 will expand and lock again under the constraint of the closed base. The combination of these two elements achieves a mechanical synergy of a rigid frame resisting temperature changes and maintaining volume, while the soft colloid uses water pressure to seal micro-cracks, completely solving the engineering problem that a single material cannot simultaneously address both resistance to cold contraction and resistance to vibration-induced micro-leakage.

[0059] To ensure the reliability of the aforementioned multi-stage tandem composite sealing architecture, the assembly and construction of the device in this embodiment must strictly follow the following steps:

[0060] First, a through hole is made at a predetermined position on the hull plate 3. The cup-shaped pipe section 2 is passed through the through hole and rigidly and watertightly fixed to the hull plate 3 using a full penetration welding process. Then, the cable 1 is passed axially from inside the cabin to outside the cabin (or in the opposite direction) through the internal through channel of the cup-shaped pipe section 2 and adjusted to the predetermined position.

[0061] At the inner end of the cup-shaped pipe section 2, the first inner clamping washer 10, the first inner sealing ring 11, the second inner clamping washer 12, the second inner sealing ring 13, and the third inner clamping washer 14 are sequentially pushed into the inner hole along the outer wall of the cable 1. Finally, the inner clamping nut 15 is screwed into the internal thread of the cup-shaped pipe section 2 and the specified preload torque is applied, causing the two sealing rings to expand under pressure, thus completing the initial axial positioning and physical sealing of the inner end of the chamber.

[0062] At the inner base annular gap of the outer end of the cup-shaped pipe section 2, a metered amount of self-tightening water-pressure sealant is injected to form a bottom self-tightening water-pressure sealing layer 9. Simultaneously, a uniform layer of the same sealant with a thickness of 0.5 to 2 mm is applied to the corresponding sections of the outer sheath of cable 1 and the inner wall of cup-shaped pipe section 2 to form an interface self-tightening water-pressure coating 16. The second outer clamping washer 8 is then pushed in. Subsequently, carbon fiber packing is densely wound around the circumference of cable 1 in the annular space above washer 8. A mixture of degassed positive and negative thermal expansion composite material (polyurethane and zirconium tungstate) is injected into the mesh gaps of the carbon fiber packing and allowed to cure in situ, forming a temperature-dependent constant-volume sealing assembly 7. The first outer clamping washer 6 is pushed in above the cured assembly 7. In the remaining cavity above washer 6, self-tightening water-pressure sealant is injected again to form an end self-tightening water-pressure sealing layer 5. Finally, the outer clamping nut 4 is screwed in to provide appropriate external preload, completing the overall assembly.

[0063] In summary, this invention proposes a cable penetration sealing device based on temperature-induced constant volume and water pressure self-tightening, comprising:

[0064] The cup-shaped pipe section 2 is fixed at the opening of the hull plate 3, and the cable 1 passes through the cup-shaped pipe section 2 axially.

[0065] With hull plate 3 as the boundary, cup-shaped tube section 2 is divided into an inner end and an outer end.

[0066] The outer end of the cabin is equipped with an outer clamping nut 4, an outer first clamping washer 6, a temperature-induced constant volume sealing assembly 7, and an outer second clamping washer 8, which are coaxially assembled from the outside to the inside.

[0067] Apply a water pressure self-tightening sealing layer 5 between the external clamping nut 4 and the cable 1.

[0068] The temperature-dependent constant volume sealing assembly 7 is composed of a carbon fiber packing skeleton and positive and negative thermal expansion composite materials cured in situ in the gaps between the skeletons. The positive and negative thermal expansion composite materials are composed of positive thermal expansion polyurethane elastic substrate and negative thermal expansion zirconium tungstate filler. They are used to maintain constant volume under temperature alternation environment and provide axial rigid support for the upper end water pressure self-tightening sealing layer 5.

[0069] The bottom water pressure self-tightening sealing layer 9 is applied between the cable 1 and the cup-shaped pipe section 2 located at the position of the hull plate 3.

[0070] Both the end water pressure self-tightening sealing layer 5 and the bottom water pressure self-tightening sealing layer 9 use water pressure self-tightening sealant. The water pressure self-tightening sealant is copolymerized from acrylate monomers containing thiourea structure and mercapto crosslinking agents. It is used to generate volume expansion perpendicular to the shear force direction to tighten the cable 1 when subjected to the fluid shear force generated by the intrusion of external high-pressure seawater.

[0071] The steps in this invention can be adjusted, combined, or deleted according to actual needs.

[0072] The units in the device of the present invention can be merged, divided, or reduced according to actual needs.

[0073] In this invention, the terms "installation," "connection," "linking," and "fixing" should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; "linking" can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of these terms in this invention according to the specific circumstances.

[0074] The shapes of the components in the accompanying drawings are schematic and may differ from their actual shapes. The drawings are only used to illustrate the principles of the present invention and are not intended to limit the present invention.

[0075] Although the invention has been disclosed in detail with reference to the accompanying drawings, it should be understood that these descriptions are merely exemplary and not intended to limit the application of the invention. The scope of protection of the invention is defined by the appended claims and may include various modifications, alterations, and equivalents made to the invention without departing from the scope and spirit of the invention.

Claims

1. A cable insertion sealing device based on temperature-induced constant volume and water pressure self-tightening, characterized in that, The device includes: Cup-shaped pipe section (2) fixed at the opening of the hull plate (3), and cable (1) passing through the cup-shaped pipe section (2) axially; With the hull plate (3) as the boundary, the cup-shaped tube section (2) is divided into the inner end and the outer end; The outer end of the cabin is provided with an outer clamping nut (4), an outer first clamping washer (6), a temperature-induced constant volume sealing assembly (7), and an outer second clamping washer (8) that are coaxially assembled from the outside to the inside. Apply a water pressure self-tightening sealing layer (5) between the external clamping nut (4) and the cable (1); The temperature-dependent constant volume sealing assembly (7) is composed of a carbon fiber packing skeleton and positive and negative thermal expansion composite materials that are in situ cured in the gap of the skeleton. The positive and negative thermal expansion composite materials are composed of positive thermal expansion elastic substrate and negative thermal expansion filler, which are used to maintain constant volume under temperature alternation environment and provide axial rigid support for the end water pressure self-tightening sealing layer (5) above. The bottom water pressure self-tightening sealing layer (9) is applied between the cable (1) and the cup-shaped pipe section (2) located at the position of the hull plate (3); Both the end water pressure self-tightening sealing layer (5) and the bottom water pressure self-tightening sealing layer (9) are made of water pressure self-tightening sealant. The water pressure self-tightening sealant is an elastomer material with a dynamic cross-linking network. When subjected to the fluid shear force generated by the intrusion of external high-pressure seawater, its dynamic cross-linking network is reorganized and generates volume expansion perpendicular to the shear force direction to tighten the cable (1).

2. The cable insertion sealing device based on temperature-induced constant volume and water pressure self-tightening as described in claim 1, characterized in that, Between the temperature-induced constant volume sealing assembly (7) and the outer wall of the cable (1), and between the temperature-induced constant volume sealing assembly (7) and the inner wall of the cup-shaped pipe section (2), an interface water pressure self-tightening coating (16) with a thickness of 0.5 to 2 mm is also coated; the material of the interface water pressure self-tightening coating (16) is the same as that of the end water pressure self-tightening sealing layer (5).

3. The cable insertion sealing device based on temperature-induced constant volume and water pressure self-tightening as described in claim 1, characterized in that, The first compression washer (10), the first sealing ring (11), the second compression washer (12), the second sealing ring (13), and the third compression washer (14) are coaxially mounted on the inner end of the compartment from the side near the hull plate (3) toward the inner end; the inner end opening of the cup-shaped pipe section (2) is screwed with an inner compression nut (15), which is used to press against the third compression washer (14) to force the two sealing rings to expand radially.

4. A positive and negative thermal expansion composite material adapted to the cable penetration sealing device based on temperature-induced volume stability and water pressure self-tightening as described in claim 1, the composite material comprising: Positive thermal expansion elastic substrate, negative thermal expansion filler and coupling agent; The volume ratio of the positive thermal expansion elastic substrate to the negative thermal expansion filler is 65-75:25-35; the mass of the coupling agent is 1% to 3%. The coupling agent is a titanate coupling agent.

5. The composite material according to claim 4, characterized in that, The positive thermal expansion elastic substrate is a polyurethane elastomer; The coefficient of thermal expansion of polyurethane elastomer is 120 ppm / ℃.

6. The composite material according to claim 4, characterized in that, The negative thermal expansion filler is zirconium tungstate micro powder; The particle size of zirconium tungstate powder is 1 to 10 micrometers, and the coefficient of thermal expansion is -9 ppm / ℃.

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