Flameless thermosensitive wire and preparation method therefor

Abstract

Provided in the present invention are a flameless thermosensitive wire and a preparation method therefor. A thermosensitive wire core comprises the following components in parts by mass: 70-85 parts of a temperature-sensing agent, 8-15 parts of an oxidizing agent, 1-5 parts of a catalyst, and 4-10 parts of a flame inhibitor, wherein the catalyst is cerium dioxide or manganese dioxide. The flame inhibitor can disperse heat generated by the combustion of the wire core; therefore, heat accumulation is avoided, and the combustion temperature is reduced. However, due to the addition of the flame inhibitor, the combustion speed of the thermosensitive wire is slow. In the present invention, by adding cerium dioxide or manganese dioxide as a catalyst, the combustion of the thermosensitive wire can be accelerated, the thermosensitive wiree can be ensured to meet the practical requirement for quick action of an automatic fire-extinguishing device, the complete combustion can be promoted, the generation of combustible gases such as CO can be reduced, and the flameless combustion effect of the thermosensitive wire can be ensured.

Description

Flameless thermal wire and preparation method thereof Technical Field

[0001] The invention belongs to the technical field of fire fighting and extinguishing, and particularly relates to a flameless thermal wire and a preparation method thereof. Background Art

[0002] With the widespread use of automatic fire extinguishing devices in recent years, the use of thermal wires as detection and activation components has also been widely researched. In special environments, such as those with explosive gases, the technical requirements for automatic fire extinguishing devices have been further increased. Because thermal wires themselves produce open flames and are located outside the device, directly exposed to the protected space, the development of flameless combustion technology for thermal wires is extremely important for the application of automatic fire extinguishing devices in these special environments.

[0003] Current thermal wire technologies all involve flame combustion. While some technologies employ sleeves to reduce flames, this still doesn't fundamentally address the issue of flames or sparks during thermal wire combustion. Therefore, developing safer thermal wire technology is crucial for the widespread use of automatic fire extinguishing devices.

[0004] CN113912465 discloses a moisture-proof and waterproof thermal wire, which has excellent moisture-proof performance and good flame transmission stability. However, during the combustion process, the outer skin temperature of the thermal wire is high and flames are generated, which is not conducive to the use of the thermal wire in flame-sensitive scenes.

[0005] Summary of the Invention

[0006] The present invention provides a flameless thermal wire and a preparation method thereof, which reduces the combustion temperature of the thermal wire core so that it can achieve a flameless combustion state, broadens the application range of the thermal wire, and improves the safety of automatic fire extinguishing devices with thermal wires when used in explosive environments.

[0007] The technical solution of the present invention is a flameless thermal wire, characterized in that the thermal wire core comprises the following components by mass: 70-85 parts of a temperature sensitizer, 8-15 parts of an oxidizer, 1-5 parts of a catalyst and 4-10 parts of a flame extinguisher; wherein the catalyst is cerium dioxide or manganese dioxide.

[0008] Furthermore, the temperature sensitive agent is nitrocellulose.

[0009] Furthermore, the oxidant is one or more of potassium chlorate, potassium perchlorate, and potassium nitrate.

[0010] Furthermore, the flame retardant is one or more of clay, bentonite or diatomaceous earth.

[0011] The present invention also relates to a method for preparing the flameless thermal wire, comprising the following steps:

[0012] S1, adding a temperature sensitive agent to a solvent for mixing and dispersing to obtain a dispersion;

[0013] S2. Sieve and mix the oxidant, catalyst and flame retardant to obtain a powder;

[0014] S3, adding the powder to the dispersion, and stirring to obtain a mixture;

[0015] S4, extruding the mixture into a strip lead, and drying to obtain a thermal sensitive wire core;

[0016] S5. Put a sleeve on the outside of the thermal wire core to obtain a flameless thermal wire.

[0017] Furthermore, the solvent of S1 is an ethanol solution, and the amount of the ethanol solution added is 40-60% of the total weight of the thermal wire core.

[0018] Furthermore, the mass concentration of the ethanol solution is 50-60%.

[0019] Furthermore, during the drying in S4, the temperature is 45 to 55° C., and the drying time is more than 8 hours.

[0020] Furthermore, the sleeve is a polyethylene sleeve.

[0021] The present invention has the following beneficial effects:

[0022] The flame extinguisher in the present invention plays a crucial role in ensuring the flameless performance of the thermal wire. The addition of a flame extinguisher disperses the heat generated by the combustion of the core, preventing heat accumulation and lowering the combustion temperature. However, the addition of a flame extinguisher can slow the combustion of the thermal wire. By adding cerium dioxide or manganese dioxide as a catalyst, the present invention not only accelerates the combustion of the thermal wire, ensuring that the thermal wire meets the practical requirements of rapid activation of the automatic fire extinguishing device, but also promotes more complete combustion, reduces the production of combustible gases such as CO, and ensures the flameless combustion of the thermal wire.

[0023] The cerium dioxide and manganese dioxide catalysts used in the present invention have strong oxygen storage and release capabilities, can promote redox cycles, accelerate the conversion reaction of CO, reduce the generation of combustible gases such as CO, and inhibit the formation of surface flames. DETAILED DESCRIPTION

[0024] The embodiments of the present invention will be described in detail below with reference to examples. However, those skilled in the art will understand that the following examples are only used to illustrate the present invention and should not be regarded as limiting the scope of the present invention.

[0025] Example 1

[0026] A flameless thermal wire is prepared by adding 75 parts by mass of nitrocellulose to 40 parts of an ethanol solution (the mass concentration of the ethanol solution is 50%) and stirring to obtain a dispersion. 10 parts of potassium chlorate, 5 parts of cerium dioxide, and 10 parts of clay are sieved and mixed to obtain a powder, which is then added to the dispersion and stirred to obtain a mixture. The mixture is extruded into a strip of lead wire and dried at 50°C to obtain a thermal wire core. A polyethylene plastic sleeve is placed over the thermal core to obtain the flameless thermal wire.

[0027] Example 2

[0028] A flameless thermal wire is prepared by adding 75 parts by mass of nitrocellulose to 50 parts of an ethanol solution (the mass concentration of the ethanol solution is 50%) and stirring to obtain a dispersion. 12 parts of potassium perchlorate, 5 parts of cerium dioxide, and 8 parts of bentonite are sieved and mixed to obtain a powder. The powder is then added to the dispersion and stirred to obtain a mixture. The mixture is extruded into a strip of lead wire and dried at 50°C to obtain a thermal wire core. A polyethylene plastic sleeve is placed over the thermal core to obtain the flameless thermal wire.

[0029] Example 3:

[0030] A flameless thermal wire is prepared by adding 75 parts by mass of nitrocellulose to 60 parts of an ethanol solution (the ethanol solution has a mass concentration of 60%) and stirring to obtain a dispersion. 15 parts of potassium nitrate, 5 parts of manganese dioxide, and 5 parts of diatomaceous earth are sieved and mixed to obtain a powder, which is then added to the dispersion and stirred to obtain a mixture. The mixture is extruded into a strip of lead wire and dried at 50°C to obtain a thermal wire core. A polyethylene plastic sleeve is placed over the thermal core to produce the flameless thermal wire.

[0031] Example 4:

[0032] A flameless thermal wire is prepared by adding 80 parts by mass of nitrocellulose to 40 parts of an ethanol solution (the ethanol solution has a mass concentration of 50%) and stirring to obtain a dispersion. 10 parts of potassium chlorate, 5 parts of manganese dioxide, and 5 parts of clay are sieved and mixed to obtain a powder, which is then added to the dispersion and stirred to obtain a mixture. The mixture is extruded into a strip of lead wire and dried at 50°C to obtain a thermal wire core. A polyethylene plastic sleeve is placed over the thermal core to produce the flameless thermal wire.

[0033] Example 5:

[0034] A flameless thermal line is prepared based on Example 4, with the following differences:

[0035] 5-1: Manganese dioxide is 1 part, clay is 9 parts, and the rest is the same as Example 4.

[0036] 5-2: Manganese dioxide is 3 parts, clay is 7 parts, and the rest is the same as Example 4.

[0037] 5-3: wherein the amount of nitrocellulose is 85 parts, the amount of potassium chlorate is 8 parts, the amount of manganese dioxide is 3 parts, and the amount of clay is 4 parts. The rest is the same as in Example 4.

[0038] Example 6:

[0039] A flameless thermal wire is prepared by adding 75 parts by mass of nitrocellulose to 40 parts of an ethanol solution (the mass concentration of the ethanol solution is 50%) and stirring to obtain a dispersion. Five parts of potassium chlorate, seven parts of potassium perchlorate, two parts of cerium dioxide, two parts of manganese dioxide, four parts of clay, and five parts of bentonite are sieved and mixed to obtain a powder. The powder is then added to the dispersion and stirred to obtain a mixture. The mixture is extruded into a strip of lead wire and dried at 50°C to obtain a thermal wire core. A polyethylene plastic sleeve is placed over the thermal core to obtain the flameless thermal wire.

[0040] Comparative Example 1:

[0041] A thermal line is based on Example 1, except that the amount of nitrocellulose is 78 parts, the amount of potassium chlorate is 12 parts, and the amount of clay is 10 parts.

[0042] Comparative Example 2:

[0043] A thermal line is based on Example 1, except that the amount of nitrocellulose is 85 parts, the amount of potassium chlorate is 10 parts, and the amount of cerium dioxide is 5 parts.

[0044] Comparative Example 3

[0045] A thermal wire is based on Example 1, except that an equal amount of clay is replaced by magnesium carbonate.

[0046] Comparative Example 4

[0047] A thermal line is based on Example 1, except that nitrocellulose is 77.5 parts, potassium chlorate is 12 parts, clay is 10 parts, and cerium dioxide is 0.5 parts.

[0048] Comparative Example 5

[0049] A thermal wire is based on Example 1, with the only difference being that an equal amount of cerium dioxide is replaced by ferric oxide.

[0050] Comparative Example 6

[0051] A thermal line is based on Example 1, except that an equal amount of cerium dioxide is replaced by ferrocene.

[0052] The thermosensitive wires prepared in the above examples and comparative examples were placed in an electric blast drying oven, and the ignition temperature of the thermosensitive wires was tested by slowly increasing the temperature. They were then installed as detection and starting components in an automatic fire extinguishing device for a start-up test. The test results are shown in Table 1 below.

[0053] Table 1

[0054] The samples provided by the present invention can all be ignited smoothly at 180-190°C and can successfully activate the automatic fire extinguishing device. Compared with the sample thermal wire without the addition of flame retardant, the thermal wire of the present invention does not produce visible combustion flames during combustion, and the casing remains intact after combustion without damage, etc., indicating that the thermal wire prepared by the present invention achieves the effect of flameless combustion and can meet the requirements of flameless activation of the automatic fire extinguishing device. In Comparative Examples 5 and 6, although the ignition temperature of the samples using ferric oxide or ferrocene as the catalyst is not significantly different from that of the samples of the present invention, the burning rate does not achieve the expected effect and is not suitable for practical application.

[0055] The above embodiments are merely illustrative of the technical concepts and features of the present invention. The contents described are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Within the technical scope disclosed by the present invention, equivalent changes or improvements based on the technical solutions and inventive concepts of the present invention are all encompassed within the scope of protection of the present invention.

Claims

1. A flameless thermal wire, characterized in that: The thermal sensitive wire core comprises the following components by mass: 70-85 parts of a temperature sensitizer, 8-15 parts of an oxidant, 1-5 parts of a catalyst and 4-10 parts of a flame extinguisher; wherein the catalyst is cerium dioxide or manganese dioxide.

2. The flameless thermal wire according to claim 1, characterized in that: The temperature sensitive agent is nitrocellulose.

3. The flameless thermal wire according to claim 1, characterized in that: The oxidant is one or more of potassium chlorate, potassium perchlorate and potassium nitrate.

4. The flameless thermal wire according to claim 1, characterized in that: The flame retardant is one or more of clay, bentonite or diatomaceous earth.

5. The method for preparing the flameless thermal wire according to any one of claims 1 to 4, characterized in that: The following steps are involved: S1, adding a temperature sensitive agent into a solvent for mixing and dispersing to obtain a dispersion; S2, sieving and mixing the oxidant, the catalyst and the flame retardant to obtain a powder; S3, adding the powder to the dispersion, and stirring to obtain a mixture; S4, extruding the mixture into a strip lead, and obtaining a thermal sensitive wire core after drying; S5. Sleeve the sleeve onto the outside of the thermal wire core to obtain the flameless thermal wire.

6. The preparation method according to claim 5, characterized in that: The solvent of S1 is ethanol solution, and the added amount thereof is 40-60% of the total weight of the thermal wire core.

7. The preparation method according to claim 6, characterized in that: The mass concentration of the ethanol solution is 50-60%.

8. The preparation method according to claim 5, characterized in that: During the drying in S4, the temperature is 45 to 55° C. and the drying time is more than 8 hours.

9. The preparation method according to claim 5, characterized in that: The sleeve is a polyethylene sleeve.

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