Ship anti-reburning safe cabin opening system and method based on external continuous supply

Abstract

The invention provides a ship anti-reburning safe cabin opening system and method based on external continuous supply, and relates to the technical field of ship fire fighting and safety. The system comprises a cabin body interface which is pre-buried in the outer side wall of a ship cabin body and penetrates through the cabin wall, and the cabin body interface is provided with a detachable screw cover; the conveying pipeline is used for connecting the cabin body interface with an external fire extinguishing agent supply device; the external fire extinguishing agent supply device is integrated with a control system and is used for adjusting the conveying pressure and the flow speed of the fire extinguishing agent; the system is suitable for secondary and above fire extinguishing after first fire extinguishing, before cabin opening and after cabin opening of a ship, and a fire extinguishing agent is continuously conveyed into a cabin through a cabin body connector so as to completely eliminate smoldering and after-combustion hidden dangers. According to the system, secondary or more fire extinguishment can be carried out after a ship completes first fire extinguishment, before cabin opening operation and after cabin opening, accurate detection and continuous extinguishment of a smoldering point in a cabin are achieved, the possibility of after-combustion is completely eradicated, and the safety of goods and equipment in the cabin is protected to the maximum extent.

Description

Technical Field

[0001] This application relates to the field of ship fire protection and safety technology, and is particularly applicable to the safe opening of cabins on ships such as large passenger cabins, ro-ro passenger ships, and cargo ships after fire fighting. Specifically, it relates to a ship anti-reignition safe opening system and method based on continuous external supply. Background Technology

[0002] Ship fires pose a significant safety hazard in maritime transport, especially on large passenger ships, ro-ro passenger ships, and cargo ships. These vessels have complex cabin structures, carry a wide variety of cargo, and are densely populated with people; the consequences of a fire on such a ship would be unimaginable. Currently, these types of ships are generally equipped with fixed shipboard fire suppression systems, such as high-pressure carbon dioxide fire suppression systems and foam fire suppression systems.

[0003] Among related technologies, Chinese invention patent CN114010991A discloses a battery-powered fire extinguishing system and a ship. This system uses steel cylinders to store the extinguishing agent, with a storage capacity slightly higher than the amount needed for a single fire extinguishing. While it can achieve initial fire suppression, it cannot handle reignition or smoldering. Chinese invention patent CN113786570A discloses a semi-cooled, semi-pressurized carbon dioxide fire extinguishing system. Although it utilizes CO2 storage tanks on board for fire extinguishing, the system becomes completely ineffective if the tanks are damaged or leak. Utility model patent CN222445226U proposes multiple independent fire extinguishing devices to achieve multiple fire suppressions; however, this solution significantly increases the ship's load and maintenance costs, and the device layout is limited, making it difficult to cover the entire ship. Chinese invention patent CN111375160A discloses a foam-based ship fire extinguishing system; however, foam extinguishing agents are highly corrosive and can cause secondary damage to cargo and equipment inside the hold, and their diffusion and extinguishing efficiency in the ship's enclosed compartments are limited.

[0004] However, in actual firefighting operations on ships with large passenger cabins and ro-ro passenger ships, the existing technology has the following prominent shortcomings: 1) Incomplete fire extinguishing and risk of reignition: Shipboard fire suppression systems typically cease operation after extinguishing open flames, making it difficult to detect and extinguish hidden smoldering points. Once the hatches are opened, the influx of oxygen can easily trigger reignition or even deflagration, causing secondary disasters.

[0005] 2) Insufficient system dependence and reliability: Existing systems mostly rely on fixed storage tanks or cylinders on board. Since the number of fixed storage tanks or cylinders on board is limited, once the stock is insufficient or the equipment fails, the continuous firefighting capability is lost. Especially when the ship's sealed structure is damaged due to years of disrepair or fire, the firefighting space expands and the required fire extinguishing dosage increases dramatically, which the existing system cannot meet.

[0006] 3) Economic losses and environmental risks: Engine room fires may cause power system failure and huge economic losses; fuel tank fires are prone to explosions, leading to fuel leaks and serious pollution of the marine environment.

[0007] In summary, large passenger roll-on / roll-off ships and passenger cabin ships often have their hold densely packed with vehicles, container cargo, and various flammable materials. Once such a fire occurs, the fire can spread rapidly within the enclosed space, and the accumulation of heat and the increase in the concentration of flammable gases can induce deflagration or even explosion. Its destructive power far exceeds that of ordinary open flames, and it can cause severe damage to the hull structure, paralysis of the core control system, and catastrophic loss of the cargo in a very short time, resulting in a huge economic and safety disaster.

[0008] Existing shipboard fire suppression systems, whether high-pressure carbon dioxide or foam systems, have fundamental flaws in dealing with such complex fires. High-pressure carbon dioxide is limited by the availability of fixed storage tanks or cylinders on board, making it difficult to guarantee continuous and complete fire suppression. On the other hand, chemical extinguishing agents such as foam can cause widespread pollution and corrosion of cargo and equipment, resulting in secondary damage where the fire is extinguished but the cargo is destroyed, causing huge economic losses to cargo owners.

[0009] Despite the existence of various shipboard fire suppression system designs, recent rescue operations involving large passenger and cargo ships in the Bohai Bay and other areas have revealed a common predicament for existing technologies when facing complex cabin structures, the risk of smoldering and reignition in deep compartments, and the need to protect high-value cargo. Specifically, once the ship's onboard fire extinguishing agent is depleted, rescue efforts become reactive; and external rescue forces, lacking rapid, safe, and standardized means of connecting with the ship's fixed fire suppression systems, often struggle to intervene efficiently, leading to delays in fire suppression and even secondary disasters due to improper handling. Therefore, there is an urgent need in this field for a fire suppression system and method that can seamlessly connect the ship's fixed systems with land-based unlimited fire extinguishing agent supplies, possess continuous fire extinguishing agent supply capabilities, respond rapidly, and eliminate smoldering and reignition hazards in the cabins 100% before opening, in order to ensure the safety of ships, cargo, personnel, and the marine environment. Summary of the Invention

[0010] This application aims to overcome the shortcomings of the prior art and provide a ship-based safe hatch opening system and method for preventing reignition based on continuous external supply. This system and method can achieve multiple, continuous and precise extinguishing of smoldering points or reignition sources in the hatch at any time after the ship has completed the initial fire extinguishing, before hatch opening operations, and after the hatch is opened and signs of reignition are found, completely eliminating the possibility of reignition. By using clean fire extinguishing media with almost zero residue, such as low-pressure carbon dioxide, it can maximize the protection of the value of cargo and the integrity of equipment in the hatch while effectively extinguishing the fire.

[0011] The technical solution adopted in the embodiments of this application is as follows: In a first aspect, embodiments of this application provide a shipboard fire prevention and safe hatch opening system based on continuous external supply, comprising: The hull interface is embedded in the outer wall of the ship's hull and penetrates the hull wall. The hull interface is equipped with a detachable screw cap. A delivery pipeline is used to connect the cabin interface to an external fire extinguishing agent supply device; An external extinguishing agent supply device is integrated with a control system for regulating the delivery pressure and flow rate of the extinguishing agent. The system is suitable for continuously delivering extinguishing agent into the cabin through the cabin interface after the initial fire extinguishing, before the cabin is opened, and for secondary and subsequent fire extinguishing operations after the cabin is opened, so as to completely eliminate the risk of smoldering and reignition.

[0012] By adopting the above technical solution, this system creatively constructs a new fire-fighting support mode that combines shipborne fixed interfaces with land-based mobile supply. During the ship design and construction phase, through-type hull interfaces are pre-embedded at key locations on the external sidewalls of each compartment. These interfaces serve as standardized safety channels connecting the ship's enclosed internal space to an unlimited external source of extinguishing agents. When a fire occurs on the ship and initial fire suppression is completed by the self-contained system, the main hatch can be opened without risking the hazard of opening it; the system can then quickly connect to the delivery pipeline and a land-based tanker truck with continuous supply capabilities. The intelligent control system integrated into the tanker truck can precisely and dynamically regulate the delivery pressure and flow rate of the extinguishing agent, ensuring that the extinguishing agent is injected into the compartment in the optimal physical state and with the best coverage efficiency. This fundamentally overcomes the bottlenecks of traditional shipborne fire-fighting systems, which have limited storage capacity and cannot operate continuously. It enables long-term, uninterrupted suppression and extinguishing of all potential smoldering points within the compartment before opening, completely eliminating the fatal risk of reignition or even deflagration due to oxygen influx. This provides an absolutely reliable safety prerequisite for subsequent safe maintenance, cargo rescue, and personnel entry.

[0013] In one optional implementation, the conveying pipeline is a multi-layer composite flexible pipeline, which includes, from the inside out, a chemically inert inner lining layer, a mechanical strength support layer, a heat insulation layer, and a wear-resistant and flame-retardant outer coating layer.

[0014] By adopting the above technical solution, the delivery pipeline uses a specially designed multi-layered composite flexible structure. Each layer is designed for a specific project. The chemically inert inner lining layer ensures the long-term compatibility and purity of the pipeline with various extinguishing media; the high-strength support layer gives the pipeline excellent pressure resistance and deformation resistance, ensuring reliable delivery in complex terrain; the high-efficiency heat insulation layer effectively blocks the exchange of heat between the inside and outside, maintaining the optimal operating temperature range of the extinguishing agent and preventing premature vaporization or low-temperature embrittlement of the pipeline; the wear-resistant and flame-retardant outer cladding layer provides ultimate physical protection and fire safety in harsh deck environments. This composite design enables a single pipeline to simultaneously possess flexibility, strength, heat insulation, durability, and safety, becoming a reliable "lifeline" connecting ships and land-based supply sources.

[0015] In one alternative implementation, the conveying pipeline is provided with multiple sections, and the sections are quickly connected by threaded connections of male and female connectors.

[0016] By adopting the above technical solution, the delivery pipeline employs a multi-section modular design and achieves rapid sealing connections via male and female threaded connections. This design endows the system with extremely high on-site adaptability and deployment flexibility, allowing for free combination of the required pipeline lengths based on ship size, hold layout, and dock space conditions. This avoids problems such as dragging difficulties and easy kinking associated with using a single ultra-long pipeline. Standardized interfaces ensure the airtightness and robustness of the connections, minimizing leakage and loss of extinguishing agent during delivery.

[0017] In one alternative implementation, the screw cap is provided with a waterproof sealing ring and is movably connected to the cabin interface via a safety chain.

[0018] By adopting the above technical solution, a high-performance waterproof sealing ring is embedded in the cap. After the firefighting operation is completed and the cap is tightly closed, this sealing ring provides a long-term, reliable bulkhead-level sealing effect, effectively resisting seawater immersion, salt spray corrosion, and high humidity environments that may be encountered during navigation. It prevents external media from seeping into the compartment through the interface, ensuring the watertightness of the ship and the safety of cargo during subsequent voyages, and improving the overall reliability of the system. The cap is connected to the hull interface body via a movable safety chain. This design cleverly solves the problem of the cap being easily lost or accidentally detached in complex environments such as ship vibration and wind and rain. At the same time, the movable connection method ensures that the chain will not get tangled when tightening or loosening the cap, ensuring smooth and convenient operation and reflecting human-centered design details.

[0019] In one optional embodiment, the external extinguishing agent supply device is a land tanker truck, whose control system can intelligently adjust the extinguishing agent output parameters according to the conditions inside the cabin, with a pressure range of 0.1-0.2 MPa and a flow rate range of 1-2 m / s.

[0020] By adopting the above technical solution, the tanker truck's integrated intelligent control system performs precise closed-loop control of the extinguishing agent's delivery pressure and flow rate, maintaining the pressure within the optimized range of 0.1-0.2 MPa and the flow rate within the optimized range of 1-2 m / s. This ensures that the extinguishing agent enters the compartment in the optimal atomized or diffused state, achieving an effective extinguishing concentration. Furthermore, it avoids problems such as impact damage caused by excessive pressure or localized condensation, icing, or insufficient vaporization due to improper flow rate. Intelligent control achieves an optimal balance between extinguishing efficiency and safety.

[0021] Secondly, embodiments of this application provide a method for safe hatch opening to prevent reignition of fire on ships based on continuous external supply, employing the system described in any one of claims 1-5, and including the following steps: Step S1: After the ship completes the initial fire extinguishing, use detection equipment to detect smoldering points inside the cabin; Step S2: Based on the detection results, activate the pre-embedded hull interface at the location of the smoldering point on the bulkhead, or perform sparkless quick drilling and install a temporary interface. Step S3: Connect the cabin interface to the external fire extinguishing agent supply device through the delivery pipeline, and deliver the fire extinguishing agent to the cabin at designated points; Step S4: After the extinguishing agent is delivered, conduct another chamber scan to confirm there are no smoldering points before sealing the chamber interfaces.

[0022] By adopting the above technical solutions, this application constructs a scientific, rigorous, and verifiable closed-loop safety operation process for post-fire handling on ships. This method begins with a refined risk assessment and detection of the cabin's condition after initial fire extinguishing, using advanced detection equipment to locate smoldering hazards that are difficult to detect with the naked eye. Subsequently, based on the detection results, pre-installed interfaces are flexibly activated or emergency openings are made under absolutely safe conditions to establish extinguishing agent delivery channels. By connecting to an external supply system, precise, controlled, and targeted injection of extinguishing agents is implemented. Finally, the fire extinguishing effect is rigorously verified through retesting, forming a complete logical closed loop of detection, intervention, and verification.

[0023] This method completely transforms the previous experience-based, luck-based approach to opening hatches after fire suppression. It innovatively introduces a verifiable and repeatable fire suppression guarantee mechanism, turning hatch opening operations from a high-risk activity into a predictable, controllable, and guaranteed safe procedure. This method is not limited to a single operation but has the capability to conduct secondary, tertiary, and even multiple supplementary fire suppression operations based on detection results until all potential hazards are 100% eliminated. In particular, it prioritizes low-pressure carbon dioxide as the extinguishing agent, which absorbs a large amount of heat and displaces oxygen during sublimation, resulting in high fire suppression efficiency. Furthermore, it leaves no liquid or chemical residue after sublimation, achieving zero water stains and zero corrosion protection for the cargo inside the hold, perfectly resolving the conflict between fire suppression and cargo preservation. This not only greatly improves the safety of personnel but also maximizes the protection of high-value cargo and precision equipment inside the hold from secondary damage, providing the shipping industry with a completely new standard for post-fire safety handling.

[0024] In one optional embodiment, the detection device in step S1 includes at least one of an infrared thermal imager, a thermal sensor, or a gas composition detector.

[0025] By employing the aforementioned technical solution and advanced detection equipment such as infrared thermal imagers, this method achieves non-contact, panoramic, and visual scanning of thermally abnormal areas within the cabin. Infrared technology can penetrate smoke and identify hidden heat sources deep within the structure or cargo, transforming invisible smoldering risks into intuitive thermal imaging maps. This provides extremely high-resolution spatial coordinate guidance for subsequent precise firefighting, significantly improving the comprehensiveness and accuracy of detection while ensuring that operators stay away from potentially hazardous areas.

[0026] In one alternative implementation, the sparkless rapid drilling in step S2 is performed using a hydraulic hole opener or a water jet cutting device.

[0027] By adopting the above technical solution, this method specifies the use of a hydraulic hole opener to establish emergency access in extreme situations where there are no pre-set interfaces. This equipment uses hydraulic static drive for cutting, absolutely eliminating the generation of mechanical sparks and high-temperature heat sources throughout the process, fundamentally eliminating the most dangerous ignition source when performing demolition operations near flammable and explosive environments. Its powerful output torque also ensures the speed and efficiency of the hole opening operation, achieving a perfect balance between safety and timeliness in the critical firefighting and rescue situations where every second counts.

[0028] In one optional embodiment, the extinguishing agent used in step S3 is low-pressure carbon dioxide, heptafluoropropane, or other clean extinguishing media.

[0029] By adopting the above technical solutions, this method preferentially uses clean extinguishing agents such as low-pressure carbon dioxide and heptafluoropropane. These media extinguish fires primarily through the principles of asphyxiation and chemical inhibition, and can rapidly vaporize and diffuse at normal temperature and pressure, leaving no residue. Their non-corrosive, non-conductive, and residue-free characteristics ensure that while efficiently extinguishing fires, they also protect cargo loaded inside the cabin, including electronic products, precision instruments, and valuable materials, as well as the ship's structure itself, from zero or minimal damage, greatly reducing indirect economic losses caused by fires.

[0030] In particular, the use of low-pressure carbon dioxide, i.e., dry ice, utilizes its unique sublimation properties. Dry ice directly transforms from a solid to a gaseous state at room temperature and pressure. This process absorbs a large amount of latent heat, rapidly reducing the temperature of the fire. At the same time, the released carbon dioxide gas quickly dilutes the oxygen concentration, resulting in a dual effect that effectively suppresses combustion. More importantly, dry ice leaves no liquid or solid residue after sublimation, ensuring that it does not wet, pollute, or corrode cargo, perfectly preserving the original state and economic value of the goods. It is especially suitable for fire suppression in ship holds carrying electronic products, precision machinery, high-end goods, or paper cargo, making it an ideal choice that balances ultimate fire suppression performance with ultimate cargo protection.

[0031] In one optional implementation, in step S3, the delivery parameters of the extinguishing agent are dynamically adjusted according to the cabin volume, cargo layout, and type of extinguishing agent to achieve efficient coverage and avoid damage to the cargo.

[0032] In summary, this application includes at least one of the following beneficial technical effects: 1. Completely eliminate the risk of reignition. Given the dense and easily flammable nature of cargo in the holds of large passenger roll-on / roll-off ships and passenger cabins, continuous external supply and multiple fire suppression capabilities can completely eliminate all smoldering and flammable gas accumulation before the holds are opened, fundamentally preventing potentially devastating deflagration or explosions that could occur the moment the holds are opened.

[0033] 2. Achieve zero-damage fire extinguishing and asset preservation. Using clean extinguishing agents such as low-pressure carbon dioxide, there is no residue, no corrosion, and no pollution after extinguishing the fire. In numerous actual rescue operations, it has been proven that it causes almost zero damage to ship engine room equipment, vehicles in the vehicle compartment, electronic cargo, precision instruments, etc., greatly reducing the indirect economic losses caused by fire.

[0034] 3. It is highly adaptable and reliable. The system does not rely on the ship's original fire extinguishing agent reserves and can operate continuously through external supply. It can effectively deal with fires in large spaces where the seals have failed.

[0035] 4. Safe and efficient operation: Employing spark-free opening technology and long-range detection methods ensures the safety of operators. The system's core rapid interface technology and modular delivery pipeline, tested in numerous emergency rescue operations, enable rapid and safe docking of large land tankers with ship anchoring systems within tens of minutes, significantly shortening external support response time. Its intelligent control system ensures precise and controllable delivery of extinguishing agents, improving overall rescue efficiency and success rate.

[0036] 5. It has significant economic and social benefits, avoids secondary disasters and total loss of cargo caused by reignition, and reduces the risk of marine pollution accidents. It is especially suitable for high-value, high-risk vessels such as large passenger roll-on / roll-off ships and oil tankers.

[0037] 6. Provides verifiable ultimate safety. The system has the capability for multiple, repeatable fire suppression interventions. Combined with a closed-loop verification process, it provides a verifiable and guaranteed ultimate solution for safe opening of the cabin, changing the passive situation of traditional fire suppression where safety cannot be guaranteed. Attached Figure Description

[0038] Figure 1 This is a structural diagram of the cabin interface.

[0039] Figure 2 This is a schematic diagram of the conveying pipeline.

[0040] Figure 3 This is a schematic diagram of the four-layer structure of the pipeline.

[0041] Figure 4 This is a flowchart of a safe hatch opening method for preventing reignition of fire on ships based on continuous external supply.

[0042] Explanation of reference numerals in the attached drawings: 1. Cabin interface; 2. Fixing seat; 3. Safety chain; 4. Screw cap; 5. Male connector; 6. Female connector; 7. Inner liner; 8. Support layer; 9. Insulation layer; 10. Outer cladding; 11. Delivery pipe. Detailed Implementation

[0043] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0044] In the description of the embodiments of this application, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation" and "connection" should be interpreted broadly. For example, "connection" can be a detachable connection or a non-detachable connection; it can be a direct connection or an indirect connection through an intermediate medium. "Fixed connection" refers to a connection where the relative positional relationship remains unchanged after the connection. It should be understood that when component A is fixedly connected to component C via component B, changes in the relative positional relationship due to deformation of components A, B, and C are permissible. The integrated structure obtained by the two components through a one-piece molding process means that during the formation of one of the two components, that component is connected to the other component, without requiring further processing (such as bonding, welding, snap-fit ​​connections, or screw connections) to connect the two components.

[0045] The directional terms mentioned in the embodiments of this application, such as "upper", "lower", "side", etc., are only for reference to the direction of the accompanying drawings. Therefore, the directional terms used are for better and clearer explanation and understanding of the embodiments of this application, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0046] The term "multiple" refers to at least two. The term "more than" includes the stated number. The term "and / or" describes a relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, or B alone. The terms "first," "second," etc., are used for descriptive purposes only and should not be construed as implying or suggesting relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature specified as "first" or "second" may explicitly or implicitly include one or more of that feature.

[0047] This application discloses a ship fire prevention and safe hatch opening system and method based on continuous external supply, applicable to all types of ships, especially for large passenger roll-on / roll-off ships, container ships, oil tankers and other ship types with high fire risk and significant damage impact.

[0048] Reference Figure 1 A ship fire prevention and fire suppression safety hatch opening system based on continuous external supply. The core of the system includes a pre-embedded hull interface 1, a multi-layer composite flexible conveying pipeline 11, and an external fire extinguishing agent supply device with an integrated intelligent control system, such as a land tanker.

[0049] Based on the ship's structural design and fire risk assessment, the hull interface 1 is pre-positioned in an easily accessible location on the external sidewall of each compartment and penetrates the hull wall.

[0050] The outer side of the chamber interface 1 is equipped with a screw cap 4 with a fluororubber waterproof sealing ring. The screw cap 4 is movably connected to the body of the chamber interface 1 via a safety chain 3 to prevent loss and facilitate operation. The inner side of the chamber interface 1 can be directly connected to the internal space of the chamber to ensure unobstructed injection of extinguishing agent.

[0051] Reference Figure 2 , Figure 3 The conveying pipe 11 is a key connecting component of the system. The conveying pipe 11 adopts a modular design, and the sections are quickly and sealedly connected through the threaded interfaces of the male head 5 and the female head 6, which facilitates flexible assembly according to the site distance.

[0052] The conveying pipeline 11 is a multi-layered composite flexible structure, comprising, from the inside out: Inner lining layer 7: Made of polytetrafluoroethylene (PTFE), which has excellent chemical inertness and is resistant to corrosion from various fire extinguishing agents; Support layer 8: Woven from high-strength stainless steel wire, providing excellent compressive and tensile strength and maintaining the stability of the pipe shape; Insulation layer 9: Made of closed-cell foam plastic, it effectively blocks internal and external heat exchange and prevents the extinguishing agent from vaporizing prematurely or the outer wall of the pipeline from freezing during transportation. Outer cladding 10: Made of wear-resistant and flame-retardant polyurethane to ensure the durability and fire safety of the pipeline in complex deck environments.

[0053] Pressure, flow, and temperature sensors can be integrated into the conveying pipeline 11, and the data can be transmitted to the control system in real time.

[0054] The preferred external extinguishing agent supply device is a land-based tanker truck equipped with a large-capacity storage tank. Its integrated intelligent control system includes a central controller, a parameter sensor group, an electric regulating valve, and a human-machine interface. The system can dynamically adjust the output pressure (0.1-0.2MPa) and flow rate (1-2m / s) according to the internal volume of the compartment, cargo layout, smoldering point distribution, and the physical properties of the selected extinguishing agent, such as the low-temperature characteristics of carbon dioxide and the diffusion rate of heptafluoropropane. It can also realize multiple modes such as continuous delivery and intermittent spraying to optimize the fire extinguishing effect and protect the cargo.

[0055] Reference Figure 4 The following describes a method for safe opening of ship hatches based on continuous external supply to prevent reignition of fire, which is provided by an embodiment of this application. The method described below can be referred to in correspondence with the system described above for safe opening of ship hatches based on continuous external supply to prevent reignition of fire.

[0056] S1: Comprehensive Detection and Risk Assessment. Assume an electrical fire occurs in the engine room of a large passenger ro-ro ship. The ship's fixed high-pressure carbon dioxide fire suppression system automatically activates and extinguishes the open flame. Although the open flame is extinguished, the ship's extinguishing agent reserves are usually nearing depletion. The engine room has a complex structure and dense equipment; high-temperature pipelines, insulation materials, or areas with oil accumulation can easily harbor hidden smoldering points that are difficult to detect with the naked eye. At this time, with the hatches closed and the cabin in an oxygen-deficient state, smoldering is suppressed. If the main hatch is rashly opened for maintenance or damage assessment, a large influx of fresh air will rapidly provide oxygen to the smoldering points, potentially leading to a violent reignition or even a deflagration within a short period, causing a catastrophic secondary accident.

[0057] Therefore, after the ship's onboard fire suppression system has completed its initial fire suppression, it is strictly forbidden to open the cabins immediately. An infrared thermal imager should be used to scan the bulkheads over a large area. The infrared thermal imager can convert the invisible infrared radiation emitted from an object's surface into a visible image of thermal distribution. By analyzing the thermal image, areas with abnormally high temperatures on the inner surface of the bulkhead can be clearly identified. These areas correspond to potential smoldering points within the cabin, thus allowing for the preliminary location of abnormally high-temperature areas.

[0058] For areas where infrared sensors cannot penetrate or where there are blind spots, such as deep cargo layers or structural compartments, a high-temperature resistant infrared endoscope or flexible detection probe can be inserted into the cabin through the pre-embedded cabin interface 1 for more precise positioning and scanning. Throughout the process, the operator remains in a safe area outside the cabin, achieving "observation from behind a wall," ensuring extremely high safety and accuracy.

[0059] At the same time, the ship's loading list and compartment structure diagram can be combined to comprehensively assess the possible location of smoldering points and the risk level of reignition.

[0060] S2: Interface activation or emergency opening. For example, based on the fire detection results, a key suspected smoldering area is identified below the generator base. If the smoldering point is located near the pre-embedded compartment interface 1, directly remove the cap 4 and prepare to connect the delivery pipe 11.

[0061] If the smoldering point is far away or there is no corresponding pre-embedded compartment interface 1, a new safety entry point must be created in the corresponding compartment to ensure direct extinguishing agent injection at this point. Therefore, after risk assessment, an emergency non-sparking opening should be made on the outer surface of the corresponding compartment. A hydraulic hole cutter should be used preferentially for this purpose, as it completes the cutting under pure hydraulic drive, ensuring no sparks or high temperatures throughout the process and absolute explosion-proof protection.

[0062] Immediately after drilling, install the temporary cabin interface 1 and secure it with the fixing seat 2. The specifications of the temporary cabin interface 1 are consistent with those of the pre-embedded cabin interface 1 to ensure universality.

[0063] S3: Connecting the system and precision fire suppression. Connect one end of the assembled delivery pipe 11 to the pre-buried or temporary hull interface 1, and the other end to the in-place land tanker.

[0064] The conveying pipes 11 are connected quickly and in a sealed manner via precision threads of male connector 5 and female connector 6. The team can flexibly combine the required lengths according to the site distance. For example, in this embodiment, a 40m long conveying pipe 11 is used.

[0065] The intelligent control system is activated, and initial delivery parameters are set based on the detection results from step S1. Low-pressure carbon dioxide or heptafluoropropane is preferred as the extinguishing agent, as both are clean media that sublimate rapidly in the high-temperature environment inside the cabin without damaging the cargo.

[0066] After the initial 20-minute continuous delivery, infrared monitoring showed that most high-temperature areas had subsided, but the temperature drop at some deeper locations had not reached the safety threshold. The control system then initiated a second targeted supplementary delivery, adjusting the nozzle direction and flow rate to intensify treatment of stubborn locations. A retest after 10 minutes showed that all locations met the standards. This multi-stage fire suppression mode, combining initial coverage with precise replenishment, ensured 100% coverage without any omissions.

[0067] During the delivery of extinguishing agents, the control system adjusts the pressure and flow rate in real time based on feedback from pipeline sensors.

[0068] For large spaces or areas with dense cargo, the pressure can be appropriately increased to 0.18-0.2 MPa to enhance the penetration of the extinguishing agent; for areas with precision equipment, a low-pressure, slow-speed delivery mode should be adopted.

[0069] The entire delivery process can continue until the control system determines, based on data from preset concentration or temperature sensors inside the cabin, that the extinguishing agent has reached an effective coverage concentration and has been maintained for a sufficient time.

[0070] S4: Effectiveness Verification and Safety Sealing. After the extinguishing agent delivery is completed, keep the system intact and re-measure the interior of the chamber using an infrared thermal imager and gas detection equipment.

[0071] If necessary, a second, third, or subsequent supplementary delivery can be made until all monitoring indicators confirm that there is no smoldering and the concentration of combustible gas has dropped below the safe threshold.

[0072] For example, upon inspection, the cargo inside the hold was only covered with a thin layer of condensation, which quickly evaporated, leaving no extinguishing agent residue. The vehicle's paint, interior, electronic equipment, and passenger luggage were all intact. Dry ice extinguishing agents, in their effective and residue-free manner, extinguished potential explosions while preserving property worth tens of millions, fully demonstrating the core advantage of this method: thorough extinguishing while preserving the property's integrity.

[0073] After confirming safety, disassemble the delivery pipe 11, immediately seal the cabin interface 1 tightly with the cap 4 with a waterproof sealing ring, and secure it with the safety chain 3 to prevent it from loosening during navigation.

[0074] Temporary access points can remain installed and serve as permanent backup fire protection access points for the compartment.

[0075] This example illustrates a fire in the engine room of a large passenger ro-ro ship. Even after the open flames were extinguished by the ship's high-pressure carbon dioxide system, the interiors, tires, fuel lines of hundreds of cars inside the cabin, as well as batteries in passengers' luggage, may still contain numerous smoldering points and continue to release flammable gases. This confined space filled with high-temperature flammable gases is like a giant deflagration bomb; any hasty opening to introduce oxygen could trigger a catastrophic secondary explosion, powerful enough to tear apart the bulkhead and completely destroy the cabin section and all cargo.

[0076] After our team intervened, infrared scanning revealed a persistent localized high-temperature zone at the bottom of the engine. Since there was no pre-installed interface in this area, the team used a hydraulic hole opener to create a hole in the nearest bulkhead, installed a temporary interface, and connected a low-pressure carbon dioxide tanker. Carbon dioxide was continuously supplied to this area at a pressure of 0.15 MPa and a flow rate of 1.5 m / s for approximately 20 minutes. During this time, infrared monitoring showed that the high-temperature zone gradually subsided. After the supply was completed, a follow-up test showed no abnormalities, and the interface was sealed. Subsequently, the engine room was safely opened for inspection, and no reignition occurred; the precision instruments inside the engine room were also undamaged.

[0077] Overview of the application effect verification in this embodiment: The technical concepts and core components embodied in this application's system and method, such as pre-embedded / emergency interfaces, low-pressure carbon dioxide external delivery systems, and intelligent control delivery, have been comprehensively applied and verified in real emergency rescue operations for multiple large ship fires. In handling various complex fire situations involving engine rooms, vehicle compartments, and other areas, the system has successfully achieved the following: 1) Quickly establish a safe connection: In an emergency, quickly establish a reliable connection between the land-based large-capacity fire extinguishing agent supply unit and the ship's interior, thus ensuring the lifeline for continuous firefighting.

[0078] 2) Achieving continuous suppression and extinguishing: Through the continuous supply of external tank trucks, the bottleneck of limited onboard fire extinguishing agent was overcome, and the internal smoldering fire source was suppressed and injected for a long time in a repeatable manner, ensuring the thoroughness of fire extinguishing.

[0079] 3) Achieving the dual goals of efficiency and preservation: While effectively controlling the fire and preventing deflagration, the clean fire extinguishing technology used maximizes the protection of cargo and critical equipment inside the cabin, significantly reducing the overall loss of the accident.

[0080] These practical application results fully demonstrate the outstanding effectiveness, reliability, and practical value of this solution in solving the problems of safe opening of ship compartments after a fire, preventing reignition, and protecting assets.

[0081] This application embodiment completely solves the problem of reignition after a ship fire is opened by adopting an operation mode of continuous external supply, precise fixed-point delivery, and multiple effect verifications. It realizes closed-loop safety management of fire fighting operations and is especially suitable for large passenger roll-on / roll-off ships, oil tankers, chemical tankers and other ship types with extremely high safety requirements.

[0082] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of this application can be combined with each other, and any combination of features in different embodiments is also within the protection scope of this application. That is to say, the multiple embodiments described above can also be arbitrarily combined according to actual needs.

[0083] It should be noted that all the above-mentioned figures are exemplary illustrations of this application and do not represent the actual size of the product. Furthermore, the dimensional proportions between the components in the figures are not intended to limit the actual product of this application. The above are all preferred embodiments of this application and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A shipboard fire prevention and safe hatch opening system based on continuous external supply, characterized in that, include: The hull interface (1) is embedded in the outer wall of the ship's hull and penetrates the hull wall. The hull interface (1) is provided with a detachable cap (4). Delivery pipe (11) is used to connect the cabin interface (1) to the external fire extinguishing agent supply device; An external extinguishing agent supply device is integrated with a control system for regulating the delivery pressure and flow rate of the extinguishing agent. The system is suitable for fire extinguishing after the first fire extinguishing, before the hatch is opened, and for secondary and subsequent fire extinguishing after the hatch is opened. It continuously delivers extinguishing agent into the cabin through the cabin interface (1) to completely eliminate the risk of smoldering and reignition.

2. The system as described in claim 1, characterized in that: The conveying pipeline (11) is a multi-layer composite flexible pipeline, which includes, from the inside out, a chemically inert inner lining layer (7), a mechanical strength support layer (8), a heat insulation layer (9), and a wear-resistant and flame-retardant outer coating layer (10).

3. The system as described in claim 1 or 2, characterized in that: The conveying pipe (11) is provided with multiple sections, and each section is quickly connected by a threaded connection between a male head (5) and a female head (6).

4. The system as described in claim 1, characterized in that: The cap (4) is equipped with a waterproof sealing ring and is movably connected to the cabin interface (1) via a safety chain (3).

5. The system as described in claim 1, characterized in that: The external extinguishing agent supply device is a land tanker truck. Its control system can intelligently adjust the extinguishing agent output parameters according to the conditions inside the cabin. The pressure range is 0.1-0.2MPa, and the flow rate range is 1-2m / s.

6. A method for safe hatch opening to prevent reignition of fire on ships based on continuous external supply, employing the fire extinguishing system as described in any one of claims 1-5, characterized in that, Includes the following steps: Step S1: After the ship completes the initial fire extinguishing, use detection equipment to detect smoldering points inside the cabin; Step S2: Based on the detection results, activate the pre-embedded cabin interface (1) at the location of the smoldering point on the bulkhead, or perform sparkless quick drilling and install a temporary interface. Step S3: Connect the cabin interface (1) to the external fire extinguishing agent supply device through the delivery pipe (11) and deliver the fire extinguishing agent to the cabin at a fixed point; Step S4: After the extinguishing agent is delivered, conduct another chamber detection to confirm that there are no smoldering points before sealing the chamber interface (1).

7. The method as described in claim 6, characterized in that: The detection device in step S1 includes at least one of an infrared thermal imager, a thermal sensor, or a gas composition detector.

8. The method as described in claim 6, characterized in that: The sparkless rapid drilling in step S2 uses a hydraulic hole opener or a water jet cutting device.

9. The method as described in claim 6, characterized in that: The extinguishing agent used in step S3 is low-pressure carbon dioxide, heptafluoropropane, or other clean extinguishing media.

10. The method as described in claim 6, characterized in that: In step S3, the delivery parameters of the extinguishing agent are dynamically adjusted according to the cabin volume, cargo layout and extinguishing agent type to achieve efficient coverage and avoid cargo damage.

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