Temperature sensing cable fireproof blanket based on polyimide material

Abstract

The invention relates to a temperature sensing cable fireproof blanket based on a polyimide material. Comprising a blanket body composed of outer protection layers and an inner protection layer clamped between the outer protection layers. Wherein the outer protective layer is a protective layer made of silicone rubber fireproof cloth; the inner protective layer is a protective layer made of polyimide woven cloth, ceramic fiber cloth and Kevlar cloth; and the temperature sensing device is arranged in the inner protective layer. According to the invention, the polyimide material is adopted as the middle protection layer, so that the complementation of various performance indexes is realized, and the fireproof blanket shows more excellent protection performance in high-temperature, flame and severe environments. Compared with a metal anti-explosion layer, the anti-explosion performance of the fireproof blanket is overcome, the weight distribution of the fireproof blanket is further optimized, and better guarantee is provided for multi-scene application. And the surface temperature of the cable is detected through the temperature sensing device, and early warning is carried out at an abnormal operation temperature.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of fire prevention, and particularly to a temperature-sensing cable fireproof blanket based on polyimide material. Background Art

[0002] With the multi-dimensional extension of the cable laying environment from underground channels, vertical shafts to complex joint positions, differentiated and precise requirements are put forward for the performance of fireproof blankets. Traditional fireproof materials are limited by rigid structures and fixed specifications, and it is difficult to adapt to the spatial heterogeneity and dynamic risk characteristics of the cable network. The breakthrough application of polyimide materials in the field of electric power fire prevention stems from the deep coupling of their unique molecular structure and performance advantages. The alternating arrangement of rigid aromatic rings and flexible imide groups in the main chain of this material forms a highly stable conjugated system, endowing it with excellent thermal stability and chemical inertness. In a high-temperature environment, this molecular structure can form a dense carbonized protective layer through molecular chain reconstruction, effectively blocking heat transfer and suppressing flame spread; more importantly, polyimide materials can still maintain flexibility and mechanical strength under extreme thermal shock, and this thermodynamic characteristic highly matches the characteristics of drastic temperature fluctuations in the cable fire scenario, providing a material basis for constructing a dynamic fireproof barrier.

[0003] In the prior art, cable fireproof blankets generally have problems such as large weight and difficult installation, which not only increase the use cost but also reduce the operation convenience in practical applications. In a typical 10kV cable operating environment, existing fireproof blankets generally lack key arc resistance and explosion-proof performance and cannot effectively cope with extreme situations that may occur in the high-voltage electrical environment of cables. In addition, cable temperature detection devices usually use active temperature sensors that require battery power supply. This method not only increases the energy consumption of the equipment but also reduces the overall robustness of the fireproof blanket and its maintainability during long-term use, increases the workload of regular battery replacement and maintenance, and further reduces the reliability and service life of the system. Therefore, there is an urgent need to develop a cable fireproof blanket with excellent electrical performance, light weight, easy installation, and no need for battery power supply to improve its applicability and reliability in complex environments.

[0004] Therefore, it is necessary to improve one or more problems existing in the above-related technical solutions.

[0005] It should be noted that this part aims to provide background or context for the technical solutions of the present invention stated in the claims. The description here is not admitted to be prior art just because it is included in this part. Summary of the Invention

[0006] The purpose of the present invention is to provide a temperature-sensing cable fireproof blanket based on polyimide material, thereby at least to some extent solving one or more problems caused by the limitations and defects of the related technologies.

[0007] The present invention provides a temperature-sensing cable fireproof blanket based on polyimide material, comprising:

[0008] A blanket body composed of an outer protective layer and an inner protective layer sandwiched between the outer protective layers;

[0009] Wherein, the outer protective layer is a protective layer composed of silicone rubber fireproof cloth;

[0010] The inner protective layers are respectively protective layers composed of polyimide woven fabric, ceramic fiber cloth and Kevlar cloth;

[0011] A temperature sensing device, which is arranged in the inner protective layer.

[0012] Optionally, the blanket body is provided with 5 protective layers from bottom to top; wherein, the material of the first protective layer is silicone rubber fireproof cloth; the material of the second protective layer is polyimide woven fabric; the material of the third protective layer is ceramic fiber cloth; the material of the fourth protective layer is Kevlar cloth and the material of the fifth protective layer is silicone rubber fireproof cloth; and the first protective layer and the fifth protective layer form the outer protective layer, and the second protective layer to the fourth protective layer form the inner protective layer.

[0013] Optionally, the silicone rubber fireproof cloth is 0.35mm silicone rubber fireproof cloth.

[0014] Optionally, the four sides of the silicone rubber fireproof cloth are hemmed so that the four sides of all the inner protective layers are wrapped by the outer protective layer.

[0015] Optionally, the outer protective layer and the inner protective layer are fixed to each other by a cross-shaped sewing process.

[0016] Optionally, a plurality of strap fixing buckles are further arranged on the upper surface of the fifth protective layer, and the strap fixing buckles are used to fix the straps on the blanket body.

[0017] Optionally, the plurality of strap fixing buckles are divided into multiple groups, the groups are distributed at intervals, each group is provided with at least 3 strap fixing buckles, and the strap fixing buckles in each group are distributed in a straight line.

[0018] Optionally, the outer protective layer, the inner protective layer and the strap fixing buckles are sewn with polyimide sewing threads.

[0019] Optionally, the temperature sensing device adopts a polyimide passive RFID patch temperature sensing device.

[0020] The technical solution provided by the present invention may include the following beneficial effects:

[0021] In the present invention, by using polyimide woven fabric, ceramic fiber fabric and Kevlar fabric as the intermediate protective layer, the complementary of various performance indicators is achieved, which can greatly improve the overall protection effect. The fireproof blanket shows more excellent protection performance in the face of high temperature, flame and harsh environment. Compared with the metal explosion-proof layer, it not only makes up for the deficiency in explosion-proof performance, but also further optimizes the weight distribution of the fireproof blanket, providing better guarantee for multi-scene applications. And the surface temperature of the cable is detected by the temperature sensing device, and early warning is carried out when the temperature is abnormal during operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The accompanying drawings incorporated herein and constituting a part of this specification, illustrate embodiments consistent with the present invention and, together with the description, serve to explain the principles of the present invention. It is obvious that the drawings in the following description are only some embodiments of the present invention, and those of ordinary skill in the art can obtain other drawings according to these drawings without creative efforts.

[0023] Figure 1 Schematic diagram showing the structure of a temperature-sensing cable fireproof blanket based on polyimide material in an exemplary embodiment of the present invention;

[0024] Figure 2 Schematic diagram showing the structure of a polyimide passive RFID patch temperature sensing device in an exemplary embodiment of the present invention;

[0025] Figure 3 Schematic diagram showing the structure of a fireproof blanket using a cross-shaped sewing process in an exemplary embodiment of the present invention;

[0026] Figure 4 Schematic diagram showing the structure of a fireproof blanket using a strap fixing buckle in an exemplary embodiment of the present invention;

[0027] Figure 5 Schematic diagram showing the structure of a UHF RFID passive temperature sensing system in an exemplary embodiment of the present invention;

[0028] Figure 6 Schematic diagram showing the high temperature rise experiment chart of a fireproof blanket sample in an exemplary embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0029] Example embodiments will now be described more fully with reference to the accompanying drawings. However, the example embodiments can be implemented in various forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided so that this invention will be more complete and comprehensive, and will fully convey the concept of the example embodiments to those skilled in the art. The features, structures, or characteristics described may be combined in any suitable manner in one or more embodiments.

[0030] In addition, the accompanying drawings are only schematic illustrations of the embodiments of the present invention and are not necessarily drawn to scale. The same reference numerals in the drawings denote the same or similar parts, and thus the repeated description thereof will be omitted. Some of the block diagrams shown in the drawings are functional entities and do not necessarily correspond to physically or logically independent entities.

[0031] The present invention provides a temperature-sensing cable fireproof blanket based on polyimide material. As shown in Figure 1 it includes: a blanket body composed of an outer protective layer and an inner protective layer sandwiched between the outer protective layers, and a temperature-sensing device.

[0032] Among them, the outer protective layer is a protective layer made of silicone rubber fireproof cloth. The inner protective layers are respectively protective layers made of polyimide woven fabric, ceramic fiber cloth, and Kevlar cloth. The temperature-sensing device is arranged inside the inner protective layer.

[0033] It should be understood that although the multi-layer structure can significantly improve the protection performance, in actual applications, too many layers will inevitably lead to an increase in the overall weight, affecting portability and installation efficiency. Therefore, in the design process, it is necessary to strictly control the number of layers on the premise of realizing multiple protection functions to ensure that the lightweight requirement is met. Through precise material selection and thickness control, while ensuring the basic protection function, the unit area weight can be effectively reduced to achieve the lightweight design of the entire fireproof blanket.

[0034] It should also be understood that the size of the blanket body is 60 cm × 60 cm. With relatively standardized dimensions, it can widely adapt to different types of cable trenches and shaft environments. Whether in a narrow cable trench or in a shaft with limited space, the modified fireproof blanket can provide efficient protection, and due to its lightweight design, the installation process becomes more simple and fast.

[0035] It should also be understood that the lightweight RFID temperature-sensing cable fireproof blanket based on polyimide material includes a lightweight polyimide fireproof blanket body and a ultra-high frequency RFID passive temperature sensing system. The lightweight polyimide fireproof blanket body includes a moisture-proof and heat-insulating outer layer, an arc-resistant layer, a fireproof and heat-insulating layer, and an explosion-proof layer arranged in sequence. The material of the moisture-proof and heat-insulating outer layer is 0.35 mm thick silicone rubber composite woven moisture-proof and heat-insulating material. The material of the arc-resistant layer is polyimide woven material. The material of the fireproof and heat-insulating layer is aluminum silicate ceramic fiber cloth. The material of the explosion-proof layer is Kevlar aramid woven cloth.

[0036] It should also be understood that although lightweight design is an important goal of this transformation, this project has always adhered to not changing the core functions of the cable fireproof blanket, namely ensuring its excellent insulation and fireproof performance. The selection of materials for each layer and the structural design must meet the lightweight requirements while not weakening the performance of the fireproof blanket in key aspects such as fire prevention, insulation, and explosion protection. Therefore, while optimizing the number of layers, adjusting the material thickness, and replacing high-weight materials, this project always takes ensuring the protection performance as the premise and strives to achieve the best balance between lightweight and high-efficiency protection. The ultimate goal is to construct a multi-layer polyimide fireproof blanket that is both easy to carry and can provide reliable protection under extreme conditions.

[0037] It should also be understood that the inner layer material is the core of the fireproof blanket transformation and is mainly divided into three parts: the fireproof layer, the insulation layer, and the explosion-proof layer. Although each layer undertakes specific functions respectively, after the cable catches fire, in addition to the outer silicone rubber and the core fireproof layer providing heat insulation and fire prevention effects, the other two layers (the insulation layer and the explosion-proof layer) must also have fire resistance. Otherwise, the high-temperature conduction will cause their temperatures to rise rapidly, thereby affecting the overall safety performance. Therefore, the scientific selection and optimized design of the inner layer material are crucial for ensuring the comprehensive protection ability of the fireproof blanket under extreme conditions. Among the inner layer materials, the key to preventing insulation breakdown after the cable catches fire lies in the fire resistance of the insulation layer. For this reason, this project has selected polyimide textiles as the core insulation material. Polyimide materials not only have excellent electrical insulation but also possess excellent high-temperature resistance and chemical stability, and can maintain stable structures and properties even in high-temperature environments. This material can effectively block the conduction of high temperature, ensure the insulation effect of the key layers inside the fireproof blanket, and thus prevent electrical breakdown after the cable arcs, providing a solid foundation for overall protection.

[0038] It should also be understood that removing the explosion-proof stainless steel plate is a key step. The cable fireproof blanket does not have overly high requirements for explosion-proof performance in actual applications, so there is no longer a need to retain the explosion-proof steel plate; in actual multi-scenario cable fire prevention scenarios, the presence of the explosion-proof steel plate will cause installation difficulties and the folding of the explosion-proof steel plate will scratch the fabric material of the fireproof blanket. After removing the stainless steel plate, the explosion-proof performance has decreased, but by selecting other explosion-proof materials for replacement, the safety of the fireproof blanket in different working environments is ensured. In addition, considering the lightweight requirements, in the six-layer structure of the original fireproof blanket, two layers play a key role in fire prevention and heat insulation, namely polytetrafluoroethylene fireproof cloth and ceramic fiber cloth. To further reduce the weight, this project plans to achieve the lightweight goal by removing one of them. However, to ensure the overall fireproof performance of the fireproof blanket, whether one layer can be removed still needs to be verified through a high-temperature tolerance experiment.

[0039] It should also be understood that through repeated tests and verifications, this structural combination not only demonstrates stable thermal protection capabilities in high-temperature tolerance tests, but also meets the expected indicators in terms of electrical insulation and fireproof isolation, providing solid technical support for multi-scenario applications.

[0040] By using the above temperature-sensing cable fireproof blanket based on polyimide materials, and adopting polyimide woven fabric, ceramic fiber fabric, and Kevlar fabric as the intermediate protective layers, the complementary of various performance indicators is realized, which can greatly improve the overall protection effect. The fireproof blanket shows more excellent protection performance when facing high temperature, flames, and harsh environments. Compared with the metal explosion-proof layer, it not only makes up for the deficiency in explosion-proof performance, but also further optimizes the weight distribution of the fireproof blanket, providing better guarantee for multi-scenario applications. And the surface temperature of the cable is detected through the temperature-sensing device, and early warning is given when the temperature is abnormal during operation.

[0041] Next, with reference to Figures 1 to 5 shown below, the above temperature-sensing cable fireproof blanket based on polyimide materials in this exemplary embodiment will be described in more detail.

[0042] In some embodiments, with reference to Figure 1 shown below, the blanket body is provided with a total of 5 protective layers from bottom to top; among them, the material of the first protective layer is silicone rubber fireproof cloth; the material of the second protective layer is polyimide woven fabric; the material of the third protective layer is ceramic fiber fabric; the material of the fourth protective layer is Kevlar fabric and the material of the fifth protective layer is silicone rubber fireproof cloth; and the first protective layer and the fifth protective layer form the outer protective layer, and the second protective layer to the fourth protective layer form the inner protective layer. It should be understood that from bottom to top means that when the fireproof blanket covers the cable, the side close to the cable is downward and the side far from the cable is upward. That is, the protective layer closest to the cable is the first protective layer. The inner layer materials are sequentially Kevlar woven fabric, ceramic fiber fabric, and polyimide woven fabric. The selection of each material is based on its excellent high-temperature resistance, heat insulation, and fire resistance to ensure that the fireproof blanket can exert its maximum efficiency in different application environments. This design scheme not only takes into account the requirement of light weight, but also fully meets the needs of high-temperature protection and fireproof heat insulation. The material of the arc-resistant layer is polyimide woven material, which can generate protection instantly when the cable arc occurs, preventing the arc from spreading and igniting the surrounding materials. The material of the arc-resistant layer is polyimide woven material, which can generate protection instantly when the cable arc occurs, preventing the arc from spreading and igniting the surrounding materials. The material of the explosion-proof layer is Kevlar aramid woven fabric, which has good mechanical tensor during arc explosion.

[0043] In some embodiments, with reference to Figure 1As shown, the silicone rubber fireproof cloth is 0.35mm silicone rubber fireproof cloth. It should be understood that in addition to the 0.35mm specification, there is also 1mm silicone rubber fireproof cloth for the silicone rubber fireproof cloth. Among them, the weight of each 10 square centimeter sample of 0.35mm silicone rubber fireproof cloth is 5.859g. The weight of each 10 square centimeter sample of 1mm silicone rubber fireproof cloth is 13.728g. As the first protective barrier of the overall structure, the selection of the outer layer material of the fireproof blanket is very strict. It is necessary to provide effective blockage instantly when an electric arc catches fire to prevent the flame from quickly penetrating the outer layer and burning, and it must also have excellent waterproof performance to prevent rainwater or moisture from penetrating and affecting the internal materials. At the same time, the outer layer material also needs to have good insulation performance to reduce the risk caused by electrical failures, and have sufficient wear resistance to adapt to the mechanical friction and impact suffered by the fireproof blanket during frequent handling, folding and installation. Based on the above comprehensive requirements, the silicone rubber fireproof cloth is considered an ideal choice, which shows excellent performance in aspects such as electric arc ignition, water resistance, insulation and wear resistance. Since the outer layer material does not bear the main insulation and fireproof functions, its core role is mainly to protect the internal multi-layer structure from external damage. Therefore, in the process of lightweight transformation, the selection of the outer layer material is particularly crucial. On the premise of similar fireproof performance, this project should give priority to selecting a more lightweight, thinner and more flexible silicone rubber fireproof cloth, which can not only effectively reduce the overall weight, but also improve the portability and installation flexibility of the fireproof blanket, and further optimize the performance and practicality of the entire product.

[0044] In some embodiments, referring to Figure 2 As shown, the four sides of the silicone rubber fireproof cloth are hemmed so that the four sides of all the inner protective layers are wrapped by the outer protective layer. It should be understood that in order to ensure the overall stability and high-efficiency protection performance of the fireproof blanket, polyimide sewing threads are used for firm fixation around the perimeter. The fireproof blanket straps are fixed to the lightweight fireproof blanket body using Velcro, and the Velcro design improves the ease of installation of the fireproof blanket and can adapt to the installation of the fireproof blanket under multi-scenario conditions.

[0045] In some embodiments, referring to Figure 3As shown, the outer protective layer and the inner protective layer are fixed to each other by means of a cross-shaped sewing process. It should be understood that to ensure the overall stability and high-efficiency protection performance of the fire blanket, not only polyimide sewing threads are used for firm fixation around the perimeter, but also a cross-shaped sewing technique is adopted on the surface of the fire blanket to reinforce the inner and outer materials. This stitching method enables the outer silicone rubber fireproof cloth and the inner material to be well fixed at multiple intersection points, further enhancing the structural strength and durability of the fire blanket. The cross-shaped sewing not only provides a uniform pressure distribution, avoiding material shedding or deformation caused by excessive local pressure, but also ensures that the layers of materials remain tightly bonded in a high-temperature environment. The silicone rubber fireproof cloth as the outer material has excellent high-temperature resistance and flame retardant properties, and the inner material has both electrical insulation and fireproof properties. Through the fine cross-shaped sewing technique, the combination between these two layers of materials is more firm, and the protection effect of the fire blanket can be improved.

[0046] In some embodiments, referring to Figure 4 As shown, a plurality of strap fixing buckles are further provided on the upper surface of the fifth protective layer, and the strap fixing buckles are used to fix the straps to the blanket body. It should be understood that the excellent properties of silicone rubber enable it to maintain sufficient toughness in extreme environments, ensuring that the fixing buckles will not fail due to aging or physical damage under long-term high-temperature action. In terms of the fixing design, the straps are wound around the cable through these fixing buckles. The material selection of the straps also takes into account the requirements of high-temperature resistance and flexibility, ensuring that the fire blanket closely adheres to the surface of the cable during winding, while effectively fixing the position of the fire blanket to prevent the fire blanket from shifting or falling off due to external force or environmental changes. This design not only improves the adaptability of the fire blanket, ensuring that it can meet the needs of different cable shapes, but also provides great convenience during use. Users can flexibly adjust the coverage area and fixing effect of the fire blanket by adjusting the length and position of the straps. The straps are also made of high-temperature-resistant silicone rubber material to ensure sufficient mechanical strength and stability in a high-temperature environment. To further enhance the mechanical strength and durability of the straps, a double-layer silicone rubber material is adopted in this design. This double-layer design effectively enhances the tensile resistance and abrasion resistance of the straps during long-term use, while also improving the firmness of the straps when fixing the fire blanket, ensuring that they are not easily damaged or fail under harsh working conditions. The edges of the straps are also treated with polyimide sewing threads for hemming. The high strength and high-temperature stability of this sewing thread ensure the structural integrity of the straps during use and prevent cracking or loosening due to frequent use or high-temperature environment. To further improve the convenience of use, the silicone rubber outer layer of the strap is equipped with a Velcro design. The application of Velcro enables the strap to be quickly and easily fixed to the cable. Users can adjust the tightness and position of the strap according to needs, ensuring that the fire blanket firmly covers the surface of the cable and provides efficient fire protection.

[0047] In some embodiments, referring to Figure 4 as shown, the multiple strap fixing buckles are divided into multiple groups, and the groups are distributed at intervals. Each group is provided with at least 3 strap fixing buckles, and the strap fixing buckles in each group are distributed in a straight line. It should be understood that in order to ensure the stability and convenience of the fireproof blanket in actual application, 6 strap fixing buckles are arranged on the inner side of the fireproof blanket. Each fixing buckle is made of high-temperature resistant silicone rubber material, with excellent high-temperature resistance, corrosion resistance and good mechanical strength.

[0048] In some embodiments, referring to Figure 3 as shown, the outer protective layer, the inner protective layer and the strap fixing buckles are sewn with polyimide sewing thread. It should be understood that in order to ensure that the materials of each layer of the fireproof blanket can be firmly fixed together during actual use, polyimide sewing thread is used as the key material for connection and fixation. The polyimide sewing thread has extremely high breaking strength (reaching 4556.52 N) and relatively high decomposition temperature (567 °C), which enables it to maintain excellent mechanical properties and structural stability in high-temperature environments. The high-strength sewing thread not only ensures that the layers of the fireproof blanket will not separate or fall off when subjected to high-temperature impact, but also provides reliable fixing support for the product during long-term actual use. The main body of the fireproof blanket is connected to the cable fixing strap. The material of the fireproof blanket strap is 0.35 mm thick silicone rubber composite woven moisture-proof and heat-insulating material. The strap and the outer layer of the lightweight fireproof blanket are made of 0.35 mm thick silicone rubber composite woven moisture-proof and heat-insulating material, which can provide moisture-proof, fire-resistant and partial insulation performance in multi-scene cable environments.

[0049] In some embodiments, referring to Figure 2 as shown, the temperature sensing device adopts a polyimide passive RFID patch temperature sensing device. It should be understood that by using the polyimide passive RFID patch temperature sensing device, it is not necessary to use battery power supply and it can detect the surface temperature of the cable and give an alarm when the temperature is abnormal. Referring to Figure 5 as shown, the ultra-high frequency RFID passive temperature sensing system includes a passive temperature sensor tag, an antenna, and an RFID temperature information reader / writer. The outer layer material of the passive temperature sensor tag is 0.05 mm thick polyimide film. The passive temperature sensor tag is fixed on the contact surface between the fireproof blanket and the cable surface using polyimide sewing thread. The RFID antenna is connected to the RFID reader / writer through a radio frequency cable, and the RFID reader / writer is not fixed to the fireproof blanket. The RFID reader / writer is connected to the power supply. The RFID reader / writer is connected to the computer.

[0050] By optimizing the hierarchical structure design of traditional cable fire blankets, the overall weight of the fire blankets can be reduced, the arc-resistant explosion-proof performance of the fire blankets can be improved, and they have the characteristics of being lightweight and easy to install. When the operating temperature of the cable rises and is at an abnormal operating temperature, the RFID passive temperature sensor tags transmit the surface temperature of the cable through the antenna and the reader, enabling preventive work before cable failures. When the cable is ignited by an arc, the lightweight fire blanket can prevent the fire from spreading and ensure the safety of the surrounding cable and optical fiber transmission lines. In addition, the RFID ultra-high frequency temperature sensing system does not require battery power supply, improving the overall robustness of the fire blanket and its maintainability during long-term use. The antenna of the passive temperature sensing system uses a 9dBi gain antenna to improve the stability of temperature information transmission. The passive temperature sensor tags are fixed on the contact surface between the fire blanket and the cable surface using polyimide sewing threads, and the polyimide sewing threads can work at 350°C to ensure good fixation of the temperature sensing tags to the main body of the fire blanket. The outer layer material is a 0.05mm polyimide film, which can ensure that the temperature sensing tags do not fall off during the operation of the cable at a relatively high temperature.

[0051] The following experiments were conducted on the temperature-sensing cable fire blanket based on polyimide materials of the present invention.

[0052] High-temperature experiment on the fire blanket sample in a typical 10kV application scenario

[0053] For the selected multi-layer material combination samples, high-temperature tolerance experiments were conducted on the inner layer materials and the complete fire blanket samples respectively to verify the performance of each layer of materials in an actual high-temperature environment. The total duration of the entire experiment was 30 minutes, and through intermittent measurements and data recording, its stability and thermal reaction under high-temperature exposure were comprehensively evaluated. During the experiment, first, the temperature of the front spray gun was set to 800°C, and this temperature was calibrated through a ceramic fiber cloth. The temperature on the back of the sample was measured in real-time every 5 minutes using an industrial-grade infrared thermometer. The infrared thermometer can accurately capture the temperature change on the back of the material and help monitor the temperature fluctuations at each test point in real-time.

[0054] Through the image analysis of the inner layer sample of the fire blanket after 30 minutes of high-temperature exposure at 800°C, it was found that the temperature on the back of the inner layer sample stabilized at around 173°C after the entire experiment, which was lower than the temperature on the back of the single ceramic fiber cloth. In terms of the external material, after 30 minutes of high-temperature exposure, the Kevlar material only showed carbonization at the highest point in the center position, and there was also slight carbonization on the surface layer of the surrounding area, but there was no overall damage or pyrolysis.

[0055] In actual cable fire protection applications, polytetrafluoroethylene and polyimide materials are placed on the inner layer of the ceramic fiber cloth to prevent the breakdown of the materials caused by the high voltage generated instantaneously by the cable arc. In fact, the situation where the cable catches fire for a long time at a high temperature of 800 °C is relatively rare. Therefore, in the design of the fire protection blanket, the combination of polytetrafluoroethylene and polyimide focuses more on preventing the occurrence of fires and blocking the spread of flames to the surrounding cables without faults, thereby minimizing the risk of fire to the greatest extent. Considering the electrical performance requirements of the fire protection blanket and the ablation images of the inner layer samples in the high-temperature tolerance experiment, it is considered that the selected inner layer material structure combination is reasonable. Through a reasonable combination of materials, while ensuring the fire protection performance, the weight can be effectively reduced to meet the requirements of lightweight design.

[0056] By analyzing the overall ablation process images of the lightweight fire protection blanket samples after high-temperature ablation of each layer, under the high-temperature exposure of 800 °C for 30 minutes, the temperature on the back of the fire protection blanket stabilizes at 117 °C, which is significantly lower than the temperatures during the ablation process of each single-layer material and the inner layer of the fire protection blanket. This result indicates that the two added outer layers of silicone rubber improve the heat insulation performance of the overall fire protection blanket. After 30 minutes of high-temperature exposure, the silicone rubber fireproof cloth shows obvious carbonization and hardening. Although there is no damage to each layer of material before decomposition, the hardening of the silicone rubber causes damage to the polyimide material and the innermost layer of silicone rubber during disassembly. Long-term high-temperature exposure leads to the hardening of the materials, which in turn affects their structural integrity. The polytetrafluoroethylene fireproof cloth shows deformation and shrinkage under 30 minutes of high-temperature exposure, but there is no damage. This result indicates that the polytetrafluoroethylene material has a certain thermal stability and shape retention ability, and can effectively resist the direct erosion of flames in a high-temperature environment, but its long-term high-temperature performance still needs to be considered in actual applications. Only carbonization appears on the surface layer of the ceramic fiber cloth after high-temperature exposure, but the overall flexibility remains. This shows that the ceramic fiber cloth has excellent performance in heat insulation and fire protection, can effectively isolate the heat source in a high-temperature environment, and its structure remains stable and is not easily damaged by high temperatures. For the explosion-proof material Kevlar, carbonization appears on the front surface layer, but there is no obvious deformation, indicating that it shows good high-temperature resistance and fire resistance in a high-temperature environment. There are no obvious traces on the back of the outermost layer of silicone rubber fireproof cloth after ablation, and there is no obvious deformation.

[0057] Reference Figure 6As shown, the overall performance of the fireproof blanket after lightweight transformation is excellent, and it can effectively meet the fireproof requirements of cables in multiple scenarios. Each layer of material exhibits good thermal stability and thermal decomposition resistance under high-temperature exposure. At the same time, the lightweight design of the fireproof blanket ensures the portability of the material. It can be seen from the temperature rise images of the fireproof blanket sample after lightweight transformation and the inner layer material that the changing trends of their temperature rise rates are very similar, and the overall temperature rises smoothly within 30 minutes. This indicates that the fireproof blanket can effectively control the heat conduction under high-temperature exposure, prevent excessive heat accumulation, and damage the inner layer material. After adding the outer layer of silicone rubber fireproof cloth, the overall temperature is significantly lower than that of the sample with only the inner layer material and finally stabilizes at about 117°C, which shows that the outer layer of silicone rubber fireproof cloth plays an important role in heat insulation and effectively improves the overall heat insulation performance of the fireproof blanket.

[0058] Through the analysis of the temperature rise images and the overall experimental process images, it can be clearly seen that the fireproof blanket after lightweight transformation demonstrates excellent fireproof and heat insulation performance under high-temperature conditions. The addition of the outer layer of silicone rubber not only effectively reduces the overall temperature but also enhances the high-temperature resistance of the material, enabling the fireproof blanket to maintain stability for a long time under high-temperature exposure and preventing premature failure of the internal material.

[0059] However, although the fireproof blanket after lightweight transformation performs well in high-temperature environments, the next key test will be to verify its electrical properties. The electrical property test will focus on the insulation performance of the fireproof blanket to ensure that the fireproof blanket can effectively prevent breakdown and arc short-circuit caused by electrical faults in cable fireproof applications, further ensuring its safety and applicability in multiple scenarios.

[0060] Partial discharge test of the fireproof blanket

[0061] The partial discharge test process starts with the preparation and debugging of the equipment. Before the test, first ensure that all core components on the experimental platform, such as the AC power supply, voltage regulator, transformer, oscilloscope, etc., are in normal working conditions. The voltage regulator and transformer adjust the voltage according to the experimental requirements to simulate different voltage conditions. At the same time, the temperature control system also needs to be set within a predetermined range to ensure a stable experimental environment. Various sensors (such as HFCT high-frequency current sensors and ultrasonic sensors) also need to be debugged to ensure that they can monitor the partial discharge signals in the cable in real time.

[0062] At the start of the test, the fireproof blanket sample was pressurized using a method of gradually increasing the voltage. The voltage was increased by 1 kV each time, and each voltage stage was maintained for 2 minutes to observe whether partial discharge signals would be generated. During the voltage increase process, if partial discharge occurred in the cable, high-frequency current pulse signals, optical signals, sound signals, etc. generated by the partial discharge would be captured by the sensors in real time. The high-frequency current sensor (HFCT) would monitor the high-frequency current changes in the sample and display them in real time through an oscilloscope. The oscilloscope has a sampling rate of up to 5 GS / s and a bandwidth of 1 GHz, capable of accurately recording the waveforms of partial discharges and providing data support for subsequent analysis.

[0063] Meanwhile, the experimental platform used the LabVIEW system for data acquisition and processing. Through the virtual instrument driver, the oscilloscope and the LabVIEW system achieved communication and transmitted signal data in real time. During the experiment, by analyzing the waveforms of partial discharge signals, it was possible to determine whether there was a partial discharge phenomenon in the sample and conduct qualitative and quantitative analysis of the discharge characteristics. After the test process ended, if partial discharge signals were found at a certain voltage stage, the experiment would record the relevant data and conduct in-depth analysis. These data would be used to judge the insulation status of the sample and the operating safety of electrical equipment.

[0064] Under voltage conditions of 5 kV and below, no partial discharge phenomenon occurred in the fireproof blanket sample. This indicates that the fireproof blanket material has good insulation performance, proving that the insulation effect of the fireproof blanket meets high safety standards and is suitable for application scenarios with high requirements for insulation performance. When the voltage was continuously increased to 7.62 kV, obvious partial discharge occurred in the fireproof blanket sample. Under the voltage condition of 7.62 kV, the partial discharge image of the fireproof blanket sample showed obvious partial discharge. Although no partial discharge occurred at a lower voltage (such as 5 kV), indicating that its insulation performance was good within this range, as the voltage increased to 7.62 kV, the discharge phenomenon increased significantly, reflecting that the insulation performance of the fireproof blanket sample was gradually approaching its critical point. This phenomenon provides strong data support for early fault detection and also provides a basis for the safety during equipment operation, indicating that in practical applications, especially for the fireproof requirements of power cables, it can provide good insulation protection.

[0065] Fireproof Blanket Breakdown Experiment for 10 kV Application Scenario

[0066] In this experiment, a fireproof blanket breakdown test platform based on a partial discharge test platform was used to evaluate the insulation performance of the fireproof blanket in a high-voltage environment. The experimental platform was constructed using the method of gradually increasing the voltage to ensure high-precision breakdown performance testing of the fireproof blanket sample at multiple voltage stages. The main components of the platform include key devices such as a power supply, a voltage regulator, a transformer, a protective resistor, a voltage monitoring device, and a grounding wire HFCT (high-frequency current transformer).

[0067] In this experiment, the voltage of the fireproof blanket sample was gradually increased, and its electrical performance was observed. When the voltage was gradually increased to 7.98 kV, an obvious breakdown phenomenon occurred in the fireproof blanket sample. Before breakdown, a relatively large current sound could be perceived audibly during the experiment, indicating that the current increased rapidly inside the sample, leading to abnormal current flow and the concentration of electrical stress. When the voltage was further increased to the breakdown voltage, the signal detected by the high-frequency current transformer (HFCT) on the grounding wire increased sharply, and the signal displayed on the oscilloscope also showed obvious fluctuations, confirming that the partial discharge gradually developed into electrical breakdown. Although the fireproof blanket sample broke down at 7.98 kV, this phenomenon actually provided important information about its electrical performance. First of all, the breakdown occurred at a relatively high voltage value, which means that the sample can maintain stable insulation performance within a lower operating voltage range (i.e., before 7.98 kV), ensuring that accidental breakdown or electrical faults will not occur in actual applications. Therefore, the sample can provide effective electrical isolation and insulation protection at lower voltages, ensuring the safety of the equipment.

[0068] The following results were determined through the above experiments.

[0069] By setting up a high-temperature spray gun, an infrared thermometer, and a thermal imaging platform, the high-temperature tolerance of each layer of the fireproof blanket material was tested. The results showed that:

[0070] 1. Among the polyimide materials, the woven fabric showed the best performance. It had the smallest carbonization area at 500 °C (only slightly carbonized in the central area), the back surface temperature was stable at 345 °C, and there was no deformation or burn-through, significantly better than the non-woven fabric (obvious carbonization, 352 °C) and the blended fabric (central crack, 350 °C).

[0071] 2. Among the explosion-proof materials, Kevlar had a stable temperature rise at 500 °C (ultimately 368 °C), a relatively small carbonization area, and a stable structure, better than aramid (high temperature rise rate, 350 °C) and ultra-high molecular weight polyethylene (burned through at 155 °C). Finally, Kevlar was selected as the core material for the explosion-proof layer.

[0072] 3. Among the fireproof and heat-insulating materials, the ceramic fiber cloth had outstanding heat-insulating performance at 800 °C, with the back surface temperature only 175 °C and good flexibility maintained; the polytetrafluoroethylene cloth had a uniform temperature (252 °C) at 500 °C, slight carbonization, and a significant flame-retardant effect; the 0.35 mm silicone rubber cloth (back surface 220 °C) and the 1 mm silicone rubber cloth (back surface 203 °C) had similar performance, and the former was selected due to its lightweight advantage.

[0073] The fireproof blanket sample showed no partial discharge phenomenon under a voltage of 5 kV, and the waveform was stable, indicating that it has excellent insulation performance within the conventional voltage range. When the voltage was increased to 7.62 kV, the partial discharge signal increased significantly, but no breakdown occurred, proving that it can still provide stage protection in high-voltage scenarios. Through the step-by-step voltage increase method test, the fireproof blanket sample broke down at 7.98 kV, and the breakdown trace penetrated all material layers (carbonization, cracks, and melting). Although the breakdown voltage is relatively high, the experiment shows that the fireproof blanket can effectively isolate the electric field below 7.98 kV, meeting the insulation requirements of medium- and low-voltage cables (such as 10 kV). The odor and microscopic damage of the material after breakdown suggest that the corona resistance performance of the material needs to be further optimized, but the existing design already meets the basic protection requirements for multiple scenarios.

[0074] Through experimental optimization, while maintaining the core performance, the final structure of the lightweight fireproof blanket for the 10 kV cable scenario was determined to be: 0.35 mm silicone rubber cloth (outer layer) + polyimide woven fabric + ceramic fiber cloth + Kevlar (inner layer).

[0075] Through high-temperature, partial discharge, and breakdown experiments, the protection performance and feasibility of the lightweight fireproof blanket were comprehensively verified. Material optimization and structural innovation provide an efficient solution for cable fire protection in multiple scenarios.

[0076] In the description of this specification, the description referring to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine the different embodiments or examples described in this specification.

[0077] Those skilled in the art will readily conceive of other embodiments of the present invention after considering the specification and practicing the invention disclosed herein. The present invention is intended to cover any variations, uses, or adaptations of the present invention, which follow the general principles of the present invention and include the common general knowledge or conventional technical means in the technical field not disclosed in the present invention. The specification and examples are only regarded as exemplary, and the true scope and spirit of the present invention are pointed out by the appended claims.

Claims

1. A temperature-sensing cable fireproof blanket based on polyimide material, characterized in that, Including: A blanket body composed of an outer protective layer and an inner protective layer sandwiched between the outer protective layers; Wherein, the outer protective layer is a protective layer composed of silicone rubber fireproof cloth; The inner protective layers are respectively protective layers composed of polyimide woven fabric, ceramic fiber cloth and Kevlar cloth; A temperature sensing device, which is arranged in the inner protective layer.

2. The temperature sensing cable fire blanket according to claim 1, characterized in that, The blanket body is provided with 5 protective layers from bottom to top; wherein, the material of the first protective layer is silicone rubber fireproof cloth; the material of the second protective layer is polyimide woven fabric; the material of the third protective layer is ceramic fiber cloth; the material of the fourth protective layer is Kevlar cloth and the material of the fifth protective layer is silicone rubber fireproof cloth; and the first protective layer and the fifth protective layer form the outer protective layer, and the second protective layer to the fourth protective layer form the inner protective layer.

3. The temperature sensing cable fire blanket according to claim 2, characterized in that, The silicone rubber fireproof cloth is 0.35mm silicone rubber fireproof cloth.

4. The temperature sensing cable fireproof blanket according to claim 3, characterized in that, The edges of the silicone rubber fireproof cloth are hemmed to wrap all the edges of the inner protective layers with the outer protective layer.

5. The temperature-sensing cable fireproof blanket according to claim 4, characterized in that, The outer protective layer and the inner protective layer are fixed to each other by a cross-shaped sewing process.

6. The temperature-sensing cable fireproof blanket according to claim 5, wherein On the upper surface of the fifth protective layer, a plurality of strap fixing buckles are further arranged, and the strap fixing buckles are used to fix the straps on the blanket body.

7. The temperature-sensing cable fireproof blanket according to claim 6, characterized in that, The plurality of strap fixing buckles are divided into multiple groups, and the groups are spaced apart. Each group is provided with at least 3 strap fixing buckles, and the strap fixing buckles in each group are distributed in a straight line.

8. The temperature-sensing cable fireproof blanket according to claim 7, characterized in that, The outer protective layer, the inner protective layer and the strap fixing buckles are sewn with polyimide sewing threads.

9. The temperature sensing cable fireproof blanket according to any one of claims 1-8, characterized in that, The temperature sensing device adopts a polyimide passive RFID patch temperature sensing device.

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