B1-level metal sheath inorganic mineral insulation fireproof cable

Abstract

The utility model discloses a B1-level metal sheath inorganic mineral insulation fireproof cable, which belongs to the technical field of fireproof cables, and comprises conductors, a buffer layer, a filling layer and a sheath layer, the buffer layer is arranged outside the plurality of conductors, the plurality of conductors are mutually twisted, the filling layer is arranged outside the buffer layer, the sheath layer is arranged outside the filling layer, the buffer layer is arranged from inside to outside, and the sheath layer is arranged outside the sheath layer. Comprising a polyester tape, a double-sided synthetic mica tape and a ceramic silicone rubber tape, a filling layer comprises a glass fiber rope from inside to outside, and a sheath layer comprises a wrapping layer and a sheath. According to the utility model, the three layers of double-sided synthetic mica tapes are arranged in the buffer layer arranged at the outer side of the conductor, so that the waterproof capability and the anti-impact capability of the whole cable can be improved, and water vapor is prevented from entering the conductor to influence the cable. The ceramic silicone rubber tape can insulate heat, resist flame and resist fire, so that the double-sided synthetic mica tape is prevented from being scratched in the cabling process.

Description

Technical Field

[0001] The utility model relates to a class B1 metal-sheathed inorganic mineral insulated fire-resistant cable, belonging to the technical field of fire-resistant cables. Background Art

[0002] Mineral insulated cables are abbreviated as MI cables. When used as wiring, they are customarily called mineral cables or mineral fire-resistant cables in China. Currently, mineral insulated cables are divided into rigid and flexible fire-resistant cables. Among them, the rigid mineral insulated cable has a high structural hardness and is difficult to install, while the flexible fire-resistant cable is similar to ordinary cables and is easier to install.

[0003] Currently, most insulating materials use a single mica tape, and the overall waterproof and impact resistance capabilities are relatively poor. Especially when cabling, the mica tape is easily scratched. When cabling, a flame-retardant filling rope is used, and the wrapping material uses a high flame-retardant tape. Due to the addition of halogen-based flame retardants, smoke and toxic gases are generated during combustion, causing environmental pollution and endangering human health. When the cable is burning, the flame-retardant filling rope and the high resistance tape are all carbonized and fall off at high temperatures, greatly increasing the probability of cable breakdown and unable to meet the requirement that the fire-resistant cable still has the ability to conduct electricity under combustion conditions, which is not conducive to the operation of the power system. Content of the Utility Model

[0004] The technical problem to be solved by the utility model is: to provide a class B1 metal-sheathed inorganic mineral insulated fire-resistant cable, which solves the problems.

[0005] The technical problem to be solved by the utility model is achieved by the following technical solutions: a class B1 metal-sheathed inorganic mineral insulated fire-resistant cable, comprising

[0006] a conductor, a buffer layer, a filling layer, and a sheath layer,

[0007] The buffer layer is arranged outside multiple said conductors. The multiple conductors are twisted together. The filling layer is arranged outside the buffer layer, and the sheath layer is arranged outside the filling layer.

[0008] From the inside to the outside, the buffer layer includes a polyester tape, a double-sided synthetic mica tape, and a ceramized silicone rubber tape. The filling layer includes a fiberglass rope from the inside to the outside. The sheath layer includes a wrapping layer and a sheath.

[0009] Preferably, the conductors are made by twisting.

[0010] Preferably, there are three layers of the double-sided synthetic mica tape. The ceramized silicone rubber tape arranged on the outer layer of the double-sided synthetic mica tape can reduce the scratching of the double-sided synthetic mica tape during the cabling process.

[0011] Preferably, the wrapping layer includes, from the inside to the outside, a fiberglass tape and a ceramizable silicone rubber tape.

[0012] Preferably, there are two layers of fiberglass tapes, and a ceramizable silicone rubber tape is arranged outside the fiberglass tapes.

[0013] Preferably, the sheath includes a copper sheath.

[0014] The beneficial effects of the present utility model are as follows:

[0015] (1) Through the present utility model, three layers of double-sided synthetic mica tapes are arranged in the buffer layer disposed outside the conductor, which can improve the overall waterproof ability and impact resistance of the cable, and prevent water vapor from entering the conductor and affecting the cable. A ceramizable silicone rubber tape is arranged outside the double-sided synthetic mica tape. The ceramizable silicone rubber tape can insulate heat, resist combustion and fire, and is relatively convenient in laying, installation and use, etc.; at the same time, it avoids scratching of the double-sided synthetic mica tape during the cable stranding process, ensuring that the double-sided synthetic mica tape can be evenly attached to the buffer layer.

[0016] (2) Through the present utility model, two layers of fiberglass tapes are adopted in the wrapping layer, and a ceramizable silicone rubber tape is arranged outside the outer layer of the fiberglass tape. The fiberglass tape is an inorganic mineral insulation material with the characteristics of high temperature resistance and non-combustion. The cable can still maintain its electrical performance and structural integrity under fire conditions; the fiberglass tape can make the wrapping layer more dense, effectively preventing the insulation layer from getting damp; the fiberglass tape can increase the mechanical strength of the wrapping layer, making the cable more stable and durable under physical damage and mechanical stress. Compared with the high flame-retardant tape of traditional cables, it reduces the generation of smoke and toxic gases during combustion.

[0017] (3) Through the present utility model, a copper sheath is adopted on the outermost layer of the cable sheath layer. The copper sheath provides physical protection to prevent the cable from being mechanically damaged during use; it can effectively shield electromagnetic interference and radio frequency interference, ensuring the stable transmission of signals inside the cable; it has good high temperature resistance and can withstand relatively high temperatures without deformation or damage. When traditional cables are in a burning environment, the flame-retardant filling cords and high resistance tapes are all carbonized and fall off at high temperatures, greatly increasing the probability of cable breakdown and unable to meet the requirement that the fire-resistant cable still has the ability of circuit conduction under burning conditions, which is not conducive to the operation of the power system. Using a copper sheath on the outer layer of the cable sheath layer can ensure that when the cable is in a burning environment, the cable will not become loose or fall off due to combustion, preventing the cable from being broken down by the internal current. Description of the Drawings

[0018] Figure 1 It is a structural schematic diagram of the present utility model.

[0019] In the figure: 1 - Conductor, 2 - Polyester tape, 3 - Double-sided synthetic mica tape, 4 - Ceramicized silicone rubber tape, 5 - Glass fiber rope, 6 - Glass fiber tape, 7 - Ceramicized silicone rubber tape, 8 - Copper sheath. Specific embodiments

[0020] In order to easily understand the technical means, creative features, achieved purposes and effects of the present utility model, the present utility model will be further described below in conjunction with specific embodiments.

[0021] Embodiment 1

[0022] As Figure 1 shown, a Class B1 metal-sheathed inorganic mineral insulated fire-resistant cable includes a conductor 1, a buffer layer, a filling layer, and a sheath layer. A buffer layer is provided on the outer side of the conductor 1. Multiple conductors 1 are twisted together, and a sheath layer is provided on the outer side of the twisted conductor. A filling layer is filled in the gap between the multiple conductors 1 and the sheath.

[0023] In this embodiment, 5 conductors 1 are connected to each other in a twisted manner. A buffer layer is provided on the outer side of each conductor 1. The sheath layer is in contact with the outer side of the buffer layer of each conductor 1. A filling layer is filled in the gap between the buffer layer and the sheath layer.

[0024] Among them, the buffer layer provided on the outer side of the conductor 1 includes a polyester tape 2, a double-sided synthetic mica tape 3, and a ceramicized silicone rubber tape 4 from the inner layer to the outer layer. The polyester tape 2 is provided on the outer side of the conductor 1 and is attached to the conductor 1. The polyester tape 2 has high mechanical strength to ensure that the cable is protected from physical damage during use; the polyester tape 2 has good insulation ability to prevent current leakage. When electricity flows through the conductor 1, the polyester tape 2 is provided on the outer side of the conductor 1, and current cannot flow out of the polyester tape 2, preventing current leakage; the polyester tape 2 also has good waterproof ability to prevent water vapor from invading and ensure the normal operation of the cable in a humid environment.

[0025] The double-sided synthetic mica tape 3 has three layers and is provided on the outer layer of the polyester tape 2. The synthetic mica tape 3 is a refractory insulating material with a melting point of 1375 °C and does not produce harmful smoke when burned by an open flame. Therefore, the cable can still operate normally in a fire environment; the synthetic mica tape 3 has good softness under normal conditions and has good thermal elasticity after heat treatment and forming, and can adhere to the outer side of the polyester tape 2; the synthetic mica tape 3 does not contain crystal water, and the synthetic mica tape will decompose at high temperature, and the decomposition products do not contain crystal water. Therefore, there will be no problem of the cable's high-temperature resistance performance decreasing due to the condensation water decomposed at high temperature in a high-temperature environment.

[0026] A layer of ceramifiable silicone rubber tape 4 is wound around the outside of the double-sided synthetic mica tape 3. The ceramifiable silicone rubber tape 4 can be ceramified at high temperatures to form a hard protective shell, which can insulate heat, retard fire and resist fire; the ceramifiable silicone rubber tape 4 can be used for a long time in the temperature range of -60°C to 200°C, and the ceramifiable silicone rubber tape 4 is the same as an ordinary cable in the aspects of laying, installation and use, reducing the difficulty and complexity of use.

[0027] By winding a layer of ceramifiable silicone rubber tape 4 around the outside of the double-sided synthetic mica tape 3, it is possible to avoid the scratching of the double-sided synthetic mica tape 3 during the cabling process, which affects the use effect of the double-sided synthetic mica tape 3.

[0028] In this embodiment, the filling layer uses fiberglass rope 5 as the filling material. The fiberglass rope 5 arranged in the gap between the conductor 1 and the sheath layer is an inorganic material. The fiberglass rope 5 will not assist combustion or burn at high temperatures, and has a relatively high melting point, which can ensure that the cable will not catch fire and cause accidents such as cable breakage at high temperatures. The fiberglass rope 6 is arranged between the buffer layers and between the sheath layers, which can reduce the gap inside the cable and avoid wear and damage to the cable when the cable is squeezed.

[0029] The sheath layer is arranged outside the conductor, and the sheath layer includes a wrapping layer and a sheath. In this embodiment, the wrapping layer includes fiberglass tape 6 and ceramifiable silicone rubber tape 7 from the inner layer to the outer layer. Among them, there are two layers of fiberglass tape 6 and one layer of ceramifiable silicone rubber tape 7 in the wrapping layer. The fiberglass tape 6 is an inorganic mineral insulation material with the characteristics of high temperature resistance and non-combustion. This enables the cable to maintain its electrical performance and structural integrity in the event of a fire, and can make the wrapping layer denser, avoiding moisture ingress inside the cable, thereby improving the reliability and safety of the cable. At the same time, it enhances the mechanical strength of the insulating layer, making the cable more stable and durable under physical damage and mechanical stress.

[0030] The ceramifiable silicone rubber tape 7 arranged outside the fiberglass tape 6 can effectively separate the cable core and the copper sheath after crusting at high temperatures, reducing the probability of breakdown to the ground and playing a protective role.

[0031] In this embodiment, the sheath uses a copper sheath 8. The copper sheath 8 can provide physical protection for the cable to prevent mechanical damage to the cable during use; provide electrical shielding: the copper sheath 8 can effectively shield electromagnetic interference and radio frequency interference to ensure the stable transmission of signals inside the cable; at the same time, the copper sheath 8 has good high-temperature resistance and can withstand high temperatures without deformation or damage.

[0032] The use environment of the cable is relatively harsh, and the copper sheath 8 can ensure that the cable can still operate normally in a high-temperature environment or an environment with large electromagnetic interference and radio frequency interference.

[0033] This embodiment meets the following requirements:

[0034] 1. It meets the requirements of Class B1 for combustion performance specified in GB 31247-2014 and also meets the additional information requirements.

[0035] Combustion droppings / particles rating: d0. Requirement: No combustion droppings / particles within 1200 s.

[0036] Toxicity of smoke rating: t0. Requirement: Reach Class ZA2.

[0037] Corrosion rating: a1. Requirement: Conductivity ≤ 2.5 us / mm and pH ≥ 4.3.

[0038] 2. Fire resistance test: For the fire resistance test, it is necessary to conduct the test according to the specified values in the following table based on the measured outer diameter of the product. When conducting the test, the flame temperature is selected to be 950 °C to 1000 °C, and the combustion time is 180 min.

[0039]

[0040] The above has shown and described the basic principles, main features, and advantages of the present utility model. Those skilled in the art should understand that the present utility model is not limited by the above embodiments. Without departing from the spirit and scope of the present utility model, the present utility model will have various changes and improvements, and these changes and improvements all fall within the scope of protection required by the present utility model. The scope of protection required by the present utility model is defined by the appended claims and their equivalents.

Claims

1. A Class B1 metal-sheathed inorganic mineral insulated fire-resistant cable, comprising a conductor, a buffer layer, a filling layer, and a sheath layer. The buffer layer is disposed outside multiple said conductors, the multiple said conductors are stranded with each other, the filling layer is disposed outside the buffer layer, and the sheath layer is disposed outside the filling layer. It is characterized in that: From the inside to the outside, the buffer layer includes a polyester tape, a double-sided synthetic mica tape, and a ceramized silicone rubber tape; the filling layer includes a glass fiber rope from the inside to the outside; and the sheath layer includes a wrapping layer and a sheath.

2. The B1-level metal-sheathed inorganic mineral insulated fire-resistant cable according to claim 1, wherein: The conductors are made by stranding.

3. The B1 - class metal - sheathed inorganic mineral - insulated fire - resistant cable according to claim 1, wherein: There are three layers of the double-sided synthetic mica tape, and the ceramized silicone rubber tape disposed on the outer layer of the double-sided synthetic mica tape can reduce the abrasion suffered by the double-sided synthetic mica tape during the cabling process.

4. The B1-level metal-sheathed inorganic mineral-insulated fire-resistant cable according to claim 1, characterized in that: From the inside to the outside, the wrapping layer includes a glass fiber tape and a ceramized silicone rubber tape.

5. The B1 - class metal - sheathed inorganic mineral - insulated fire - resistant cable according to claim 4, wherein: There are two layers of the glass fiber tape, and a ceramized silicone rubber tape is disposed outside the glass fiber tape.

6. The B1 - class metal - sheathed inorganic mineral - insulated fire - resistant cable according to claim 1, wherein: The sheath includes a copper sheath.

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