An ultra-high temperature self-limiting heat tracing band

Abstract

The utility model discloses an ultrahigh temperature type self temperature limiting heat tracing band, including two conducting wires of parallelly arranged, the PTC core band of wrapping with two conducting wires outside, the circumferential side of PTC core band is provided with insulating layer, shielding layer and protective outer layer from inside to outside in proper order, PTC core band adopts high temperature resistance polymer matrix and electrically conductive filler and is formed, is used for long -term maintenance 180 DEG C high temperature, shielding layer is woven into shape, and shielding layer is embedded and is set in protective outer layer. The utility model discloses through high temperature resistance PTC core band and multilayer insulation shielding structure, realizes the stable heat tracing under 180 DEG C high temperature environment, and the temperature resistance grade of traditional heat tracing band is significantly promoted, and the temperature resistance upper limit of traditional heat tracing band is generally around 60 DEG C-130 DEG C, and the heat tracing band of the utility model can be stably operated above 180 DEG C, and the application range is greatly expanded, and the demand of more high temperature process can be satisfied.

Description

Technical Field

[0001] This utility model relates to the field of heat tracing technology, specifically to an ultra-high temperature self-regulating heat tracing cable. Background Technology

[0002] Self-regulating electric heating cables can automatically limit the heating temperature and automatically adjust the output power according to the temperature of the heated object without any additional equipment. They can be cut to any length or extended within a certain range, and can be overlapped multiple times without the risk of overheating or burning.

[0003] Currently, the maximum temperature maintained by traditional self-regulating heating cables is usually below 130℃, which cannot meet the requirements of high-temperature environments above 180℃. At such temperatures, the polymer materials inside traditional heating cables will gradually soften and deform, and the insulation performance of the insulation layer will also decrease significantly, which can easily lead to safety accidents such as short circuits. Although the constant power heating cables and MI armored cables in the existing technology can be used in high-temperature applications, they have problems such as complex temperature control, inconvenient installation, high energy consumption, and overheating risk. There is an urgent need to design an ultra-high temperature self-regulating heating cable to solve the above problems. Utility Model Content

[0004] The purpose of this invention is to provide an ultra-high temperature self-regulating heat tracing cable to address the aforementioned shortcomings in the prior art.

[0005] To achieve the above objectives, this utility model provides the following technical solution: An ultra-high temperature self-regulating heat tracing cable includes two parallel conductors and a PTC core strip wrapped around the two conductors. The periphery of the PTC core strip is provided with an insulation layer, a shielding layer and a protective outer layer from the inside to the outside. The PTC core strip is made of a high-temperature resistant polymer matrix and conductive filler, and is used to maintain a high temperature of 180°C for a long time. The shielding layer is woven and is embedded in the outer protective layer.

[0006] Furthermore, the shielding layer includes multiple tin-plated copper wires, which are woven into a tin-plated copper wire mesh, and the weaving density of the shielding layer is greater than 85%.

[0007] Furthermore, the shielding layer is integrated with the protective outer layer through an embedded encapsulation molding process.

[0008] Furthermore, the thickness of the PTC core strip is 1-1.5 mm, the thickness of the insulation layer is 0.5-1 mm, and the thickness of the protective outer layer is 0.8-1.2 mm.

[0009] Furthermore, the two conductors are made of multiple silver-plated copper wires twisted together, and a high-temperature resistant adhesive layer is provided between the conductors and the PTC core strip.

[0010] Furthermore, the insulating layer and the protective outer layer are made of fluoroplastics, the surface of the protective outer layer is provided with anti-slip texture, and the minimum bending radius of the heating tape is 12.5mm.

[0011] Furthermore, the rated voltage of the heat tracing cable is 110V-220V, the rated power is 100-300W / ㎡, and the insulation resistance is greater than 500MΩ / m.

[0012] Furthermore, the maximum sustained temperature of the heat tracing cable is 180°C, the maximum withstand temperature is 210°C, and the minimum installation temperature is -60°C.

[0013] In the above technical solution, the ultra-high temperature self-regulating heat tracing cable provided by this utility model has the following beneficial effects: By employing a high-temperature resistant PTC core strip and a multi-layered insulating shielding structure, stable heat tracing is achieved in high-temperature environments up to 180℃. The temperature resistance is significantly improved compared to traditional heat tracing cables, whose upper temperature resistance is generally around 60℃-130℃. This new type of heat tracing cable can operate stably above 180℃, greatly expanding its application range and meeting the needs of more high-temperature processes. Its flexible structure adapts to the installation of irregularly shaped equipment. The overall structure of this heat tracing cable has a certain degree of flexibility, allowing it to closely fit various shapes of pipes, tanks, and other equipment, facilitating installation. The protective outer layer effectively protects the internal structure, thereby extending the service life of the heat tracing cable and reducing maintenance costs. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this utility model. For those skilled in the art, other drawings can be obtained based on these drawings.

[0015] Figure 1 This is a schematic diagram of the overall structure of a self-regulating high-temperature tracing heat ...

[0016] Figure 2 This is a schematic diagram of the cross-sectional structure of a self-regulating high-temperature tracing heat ...

[0017] Figure 3 This is a schematic diagram of the cross-sectional structure of a self-regulating high-temperature tracing heat ...

[0018] 1. Conductor; 2. PTC core tape; 3. Insulation layer; 4. Shielding layer; 5. Protective outer layer; 6. Tinned copper wire; 7. Silver-plated copper wire. Detailed Implementation

[0019] To enable those skilled in the art to better understand the technical solution of this utility model, the present utility model will be further described in detail below with reference to the accompanying drawings.

[0020] like Figure 1-3 As shown in the figure, this utility model provides an ultra-high temperature self-regulating heat tracing cable.

[0021] It includes two parallel conductors 1, and a PTC core strip 2 wrapped around the two conductors 1. The periphery of the PTC core strip 2 is provided with an insulation layer 3, a shielding layer 4 and a protective outer layer 5 from the inside to the outside. The PTC core strip 2 is made of a high-temperature resistant polymer matrix and conductive filler, and is used to maintain a high temperature of 180°C for a long time. The shielding layer 4 is woven and is embedded in the outer protective layer 5.

[0022] Reference Figure 1 In this embodiment, the shielding layer 4 includes multiple tin-plated copper wires 6, which are woven into a tin-plated copper wire mesh. The weaving density of the shielding layer 4 is greater than 85%. The tin-plated copper wire mesh can effectively isolate the electric and electromagnetic fields generated by the internal current of the heat tracing cable from radiating outward, and at the same time prevent external electromagnetic interference from affecting the normal operation of the heat tracing cable.

[0023] Reference Figure 2 In this embodiment, the shielding layer 4 is integrated with the protective outer layer 5 through embedded encapsulation molding. The protective outer layer 5 forms a comprehensive protective enclosure for the brittle shielding layer 4, making it less susceptible to scratches, wear, or corrosion. This avoids the risk of the shielding layer 4 sliding or separating, making the structure of the heating cable more stable when bending or twisting. Without increasing the outer diameter of the product or significantly changing its flexibility, it simultaneously ensures the shielding effectiveness of the shielding layer 4 and the external physical protection of the protective outer layer 5.

[0024] Reference Figure 2 , Figure 3 In this embodiment, the thickness of the PTC core strip 2 is 1-1.5 mm, the thickness of the insulation layer 3 is 0.5-1 mm, and the thickness of the protective outer layer 5 is 0.8-1.2 mm. Thickness is one of the key factors determining resistance and power. Within this thickness range, the PTC material has sufficient volume to generate the rated power required by the design. Too thin a layer will result in excessive resistance and insufficient power, while too thick a layer will result in excessive resistance, excessive starting current, and uneven heating.

[0025] Reference Figure 2 , Figure 3In this embodiment, the two conductors 1 are formed by stranding multiple silver-plated copper wires 7 together. A high-temperature resistant adhesive layer is provided between the conductors 1 and the PTC core strip 2. Copper is an excellent conductor second only to silver. By using multiple strands of fine copper wires, the total surface area is much larger than that of a single copper wire of the same cross-sectional area, effectively reducing AC resistance and ensuring efficiency and safety when high current is passed. The silver plating layer plays a crucial protective role. Silver is chemically very stable and does not easily oxidize at high temperatures. Even if there is slight oxidation on the surface, the silver oxide still has good conductivity. The high-temperature resistant adhesive layer, through its strong adhesive force, firmly chemically bonds or mechanically anchors the conductors and the PTC core strip together, forming a complete thermodynamic whole.

[0026] In this embodiment, the insulating layer 3 and the protective outer layer 5 are made of fluoroplastics. The surface of the protective outer layer 5 is provided with anti-slip textures, and the minimum bending radius of the heating cable is 12.5 mm. Fluoroplastics are among the plastics with the highest known temperature resistance, and their long-term continuous operating temperature range can reach -200℃ to +260℃, which is far higher than the 180℃ operating temperature requirement of this utility model. At a high temperature of 180℃, the molecular structure of fluoroplastics remains extremely stable, ensuring the long-term effectiveness of insulation and protection performance.

[0027] The rated voltage of the heating cable in this embodiment is 110V-220V, the rated power is 100-300W / ㎡, and the insulation resistance is greater than 500MΩ / m. The 110V-220V rated voltage is the most common industrial and civil power standard, eliminating the need for specific voltage versions for different markets, simplifying inventory and selection processes. The 100-300W / ㎡ power range clearly informs designers and users. This product is suitable for various scenarios from moderate heat compensation to high-intensity heat maintenance. Engineers can calculate the system's heat loss based on parameters such as pipe size, medium temperature, ambient temperature, and insulation layer thickness, and then select a suitable model from the product's power range to ensure that the heat supply is greater than or equal to the heat loss, achieving effective heat tracing. The insulation resistance is greater than 500MΩ / m; this extremely high insulation resistance means that the current is strictly limited within the conductor, resulting in minimal leakage current. This parameter directly reflects the quality and integrity of the fluoroplastic insulation layer.

[0028] The maximum sustaining temperature of the heat tracing cable in this embodiment is 180°C, the maximum withstand temperature is 210°C, and the minimum installation temperature is -60°C. The maximum sustaining temperature parameter directly establishes the ultra-high temperature market positioning of this product, distinguishing it from conventional medium and low temperature heat tracing cables. The maximum withstand temperature parameter indicates that the heat tracing cable can be exposed to 210°C for a short period of time in an uncontrolled situation without immediate damage or combustion. The minimum installation temperature parameter proves that the fluoroplastic outer sheath and PTC core material can remain flexible and will not become brittle or crack at ultra-low temperatures.

[0029] Working Principle: During use, when the heating cable is connected to the rated power supply, current flows from one parallel conductor 1, laterally through the semiconductor-grade PTC core strip 2, and to another parallel conductor 1, thus forming a complete parallel circuit network. As the current flows through the PTC core strip 2, Joule heating is generated due to the resistance effect, causing the heating cable to initially heat up. At low ambient temperatures, the polymer matrix within the PTC core strip 2 is in a crystalline or compressed state, and the internal conductive particles contact each other, forming a dense network of conductive pathways. The overall resistance of the PTC core strip 2 is low, allowing for a larger current flow. Therefore, the output power is high, and the heat tracing cable heats up rapidly. As the heat tracing cable heats up or the ambient temperature rises, the polymer matrix begins to expand, which pulls apart the originally closely contacting conductive particles and sharply reduces the number of conductive paths. This causes the overall resistance of the PTC core 2 to jump exponentially. When the temperature rises to a certain value, the resistance becomes extremely high, so that the current passing through is limited to a very small level, and the heat generation also drops sharply. The heating power of the heat tracing cable and the heat lost to the outside reach a dynamic balance, and its temperature will automatically stabilize near this balance point and will not continue to rise.

[0030] The foregoing description only illustrates certain exemplary embodiments of the present invention. Undoubtedly, those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A high-temperature self-regulating heating tape, comprising two parallel conductors (1) and a PTC core strip (2) wrapped around the two conductors (1), characterized in that, The PTC core strip (2) is provided with an insulating layer (3), a shielding layer (4) and a protective outer layer (5) from the inside to the outside. The PTC core strip (2) is made of a high-temperature resistant polymer matrix and conductive filler, and is used to maintain a high temperature of 180°C for a long time. The shielding layer (4) is woven and is embedded in the protective outer layer (5).

2. The ultra-high temperature self-regulating heat tracing cable according to claim 1, characterized in that, The shielding layer (4) includes a plurality of tin-plated copper wires (6), which are woven into a tin-plated copper wire mesh, and the weaving density of the shielding layer (4) is greater than 85%.

3. The ultra-high temperature self-regulating heat tracing cable according to claim 2, characterized in that, The shielding layer (4) is integrated with the protective outer layer (5) by embedding and covering.

4. The ultra-high temperature self-regulating heat tracing cable according to claim 1, characterized in that, The thickness of the PTC core strip (2) is 1-1.5 mm, the thickness of the insulation layer (3) is 0.5-1 mm, and the thickness of the protective outer layer (5) is 0.8-1.2 mm.

5. The ultra-high temperature self-regulating heat tracing cable according to claim 1, characterized in that, The two conductors (1) are made of multiple silver-plated copper wires (7) twisted together, and a high-temperature resistant adhesive layer is provided between the conductors (1) and the PTC core strip (2).

6. The ultra-high temperature self-regulating heat tracing cable according to claim 1, characterized in that, The insulating layer (3) and the protective outer layer (5) are made of fluoroplastics. The surface of the protective outer layer (5) is provided with anti-slip texture. The minimum bending radius of the heat tracing cable is 12.5 mm.

7. The ultra-high temperature self-regulating heat tracing cable according to claim 1, characterized in that, The rated voltage of the heat tracing cable is 110V-220V, the rated power is 100-300W / ㎡, and the insulation resistance is greater than 500MΩ / m.

8. The ultra-high temperature self-regulating heat tracing cable according to claim 1, characterized in that, The maximum temperature maintained by the heat tracing cable is 180℃, the maximum temperature it can withstand is 210℃, and the minimum installation temperature is -60℃.

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