High-temperature insulating layer structure of alloy induction cable

Abstract

The utility model belongs to the technical field of insulation, and discloses a high-temperature insulating layer structure of an alloy induction cable, which comprises a plurality of glass fiber insulating layers wound on the periphery of the alloy induction cable. The glass fiber braid layer is used as the insulating layer of the cable, so that the effects of safety, high insulating strength, wear resistance, tensile resistance, drag resistance, repeated maintenance and long-term resistance to 500 DEG C can be realized.

Description

Technical Field

[0001] The utility model relates to the technical field of insulation, in particular to a high-temperature insulation layer structure of an alloy induction cable. Background Art

[0002] At present, the insulation layer structure used by alloy induction cables is to install a sleeve made of braided stainless steel wire on the outer shell of the alloy induction cable to enhance the tensile and drag resistance of the cable. The stainless steel wire braided sleeve is in direct metal contact with the alloy induction cable. The defects brought by the stainless steel wire braided sleeve are:

[0003] 1. Stainless steel wires may occasionally break or break after wear. The broken stainless steel wires may pierce the outer fiberglass insulation casing, causing leakage and electric shock accidents to operators. If the broken stainless steel wires come into contact with adjacent cables or workpieces, they may also cause short circuits. During the induction heating process, operators are often required to manually adjust the cable position. In actual use, there have been many accidents of electric shock caused by contact between broken stainless steel wires and human hands. There have also been cases where broken stainless steel wires short-circuited with adjacent cables, causing arc discharges and cable failures. There have also been cases where broken stainless steel wires came into contact with workpieces, causing discharges and workpiece failures. Therefore, this structure presents serious safety hazards.

[0004] 2. Put another layer of thick fiberglass casing or two layers of thin fiberglass casing outside the stainless steel braided casing. Because these casings are prefabricated, they are manually inserted into the cable of the stainless steel wire braided casing. Since the inner diameter of the fiberglass insulation casing does not match the outer diameter of the stainless steel wire braided layer, there is a gap between the two. During the cable winding, storage, and dragging process, the fiberglass casing will constantly rub against the stainless steel wire braided layer, causing wear.

[0005] 3. The stainless steel braided outer layer will cause the diameter and weight of the induction cable to increase. Since the induction cable often needs to be manually wound around the workpiece repeatedly, and the length of a single induction cable generally needs to be 15-100m, it is not convenient to construct a heavy induction cable. After being wound, the heavy induction cable is prone to droop, causing the temperature under the workpiece to be low, resulting in uneven temperature. The cable diameter increases but the effective overcurrent cross-sectional area does not increase, so for the same width of the workpiece, the number of turns that can be wound will decrease, which reduces the power output capacity of the power supply.

[0006] 4. Since the stainless steel wire braid and glass fiber insulation sleeve are prefabricated and inserted into the alloy induction cable manually, it is difficult to produce cables longer than 20m. However, engineering applications often require a single induction cable longer than 50m for high-power power supply and induction heating of large workpieces, making it difficult to produce long cables.

[0007] 5. The insulation layer of the stainless steel wire braided casing is worn from the inside to the outside. Therefore, once it is damaged, it is impossible to use insulation remedial measures such as external wrapping. If the stainless steel braided casing is broken, it is impossible to repair it and the cable can only be scrapped. It is difficult to repair and the cost of use is high. Utility Model Content

[0008] In order to solve the above technical problems, a high-temperature insulation layer structure of an alloy induction cable is provided, which adopts a glass fiber braided layer as the insulation layer of the cable, which can achieve the effects of safety, high insulation strength, wear resistance, tensile and drag resistance, repeatable repairability, and long-term tolerance of 500°C.

[0009] In order to achieve the above purpose, the technical solution adopted by the utility model is: a high-temperature insulation layer structure of an alloy induction cable, including multiple layers of glass fiber insulation layers wound around the outer circumference of the alloy induction cable.

[0010] According to the utility model, further, the glass fiber insulation layer is woven from glass fibers, and the weaving directions of two adjacent layers are opposite.

[0011] According to the utility model, further, the glass fiber has 8 to 16 layers.

[0012] According to the utility model, further, a glass fiber sleeve is sleeved on the outer periphery of the glass fiber insulation layer.

[0013] Compared with the prior art, the beneficial effects of the utility model are: 1. The glass fiber braided layer as the insulating layer of the cable is safe, has high insulation strength, is wear-resistant, resists tensile and dragging, is repeatable and repairable, and can withstand 500°C for a long time.

[0014] 2. The utility model is mainly used as an induction coil of medium frequency induction heating equipment, which is usually wound around the metal workpiece to be heated manually or mechanically, and the workpiece is heated by electromagnetic induction. It can also be used for medium frequency and high current connection in high temperature occasions.

[0015] 3. The glass fiber braided layer will not be affected by the medium frequency current to generate eddy current, which improves the system efficiency, reduces the cable temperature, and improves the output power capacity of the induction cable. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 The utility model is a schematic structural diagram of a high-temperature insulation layer structure of an alloy induction cable.

[0017] The numbers in the figure are: 1-alloy induction cable, 2-glass fiber insulation layer, 3-heat-resistant and wear-resistant outer casing. DETAILED DESCRIPTION

[0018] The following description is used to disclose the present invention so that those skilled in the art can implement the present invention. The preferred embodiments described below are only examples, and those skilled in the art may think of other obvious variations.

[0019] like Figure 1 As shown, a high-temperature insulation layer structure of an alloy induction cable is used in the field of cable insulation, including an alloy induction cable 1, each cable is woven by hundreds of thin wires according to certain rules, and each thin wire is insulated from each other; in order to insulate the alloy induction cable, a glass fiber insulation layer 2 is arranged on the periphery of the alloy induction cable 1; preferably, the glass fiber insulation layer 2 uses 8-16 layers of glass fiber weaving as the insulation layer, and the process is forward and reverse cross weaving. Therefore, the insulation strength is high, and the tensile and drag strength are also high. The glass fiber insulation layer 2 is woven by multiple layers of glass fiber. If the surface insulation is damaged, it can be wrapped and repaired without affecting the insulation effect of the inner layer; and the weaving of the above-mentioned glass fiber insulation layer 2 is completed on the cable production line, without the need to manually use the sleeve insertion method, so the glass fiber insulation layer 2 is tightly fitted to the cable, and there is no relative movement between the contact surfaces of the two, and there is no internal wear problem; and long cables can be produced, and there is no length limit in theory.

[0020] In order to further improve the insulation level of the cable, a glass fiber sleeve 3 is sleeved on the outer periphery of the glass fiber insulation layer 2, and the glass fiber sleeve 3 is a commercially available product. The glass fiber sleeve 3 has the characteristics of heat resistance and wear resistance, which can not only improve the insulation level of the cable, but also protect the glass fiber insulation layer and reduce the wear of the glass fiber insulation layer. If a small area of ​​wear occurs on the outer sleeve, it can be repaired by wrapping it with a high-temperature adhesive tape; even if the inner glass fiber braided layer 2 is damaged, it will not be damaged in a large area because of the large number of layers, thick thickness, and forward and reverse cross-braiding structure. The inner layer can also be repaired by wrapping it with a high-temperature alkali-free glass fiber tape.

[0021] Compared with stainless steel wire, glass fiber is lighter and thinner. For the alloy induction cable with a cross-sectional area of ​​130mm2, the outer diameter of the cable wound with stainless steel wire is 30mm, while the outer diameter of the cable wound with glass fiber insulation layer 2 is 25mm. The weight of the cable with glass fiber insulation layer 2 is reduced by 20%, so it is easier to operate on site, more turns can be wound, and the output power can be increased. For example: because the diameter of the cable with the same cross-sectional area is reduced from 30mm to 25mm, due to the reduction in diameter, 30 / 25=1.2 times more cables can be wound under the same workpiece width, so the induced current obtained by the cable is also 1.2 times. According to Joule's heat law, power is the square relationship of current, that is: Therefore, under the same medium frequency current, the power of winding the glass fiber insulation layer 2 is 1.44 times that of winding the stainless steel wire.

[0022] Example

[0023] The test conditions of the alloy induction cable of the utility model are as follows: it is wound around a steel drum with a diameter of 400 mm and a length of 300 mm, and wound 12 times. A 40 mm thick insulation blanket is wrapped between the steel drum and the cable. A 10 kHz intermediate frequency current is passed through the induction cable to heat the steel drum to 800°C for two hours. The temperature of the induction cable itself is 350°C, and the operation is stable and normal.

[0024] Results: 1. Under the same medium frequency current, the alloy induction cable of the utility model can be wound 12 times, and the output power can be 50kW; the traditional cable can be wound 10 times, and the output power can be 35kW;

[0025] 2. The diameter of the alloy induction cable of the utility model with a cross-sectional area of ​​130 square meters is 25 mm (including the glass fiber sleeve 3), while the diameter of the traditional alloy induction cable is 30 mm.

[0026] 3. The induction cable is 20% lighter and has a minimum bending diameter of 75mm.

[0027] 4. No obvious wear was observed after repeated winding for more than 100 times.

[0028] 5. The length of the test cable is 80m, and the test insulation level and resistivity level are normal.

[0029] The above shows and describes the basic principle, main features and advantages of the utility model. Those skilled in the art should understand that the utility model is not limited by the above embodiments. The above embodiments and the specification only describe the principles of the utility model. The utility model may be subject to various changes and improvements without departing from the spirit and scope of the utility model. These changes and improvements fall within the scope of the utility model to be protected. The scope of protection claimed by the utility model is defined by the attached claims and their equivalents.

Claims

1. A high temperature insulation layer structure of an alloy induction cable, characterized in that: It comprises multiple glass fiber insulation layers, which are wound around the outer periphery of the alloy induction cable; the glass fiber insulation layers are woven from glass fibers, and the weaving directions of two adjacent layers are opposite; and the outer periphery of the glass fiber insulation layers is sheathed with a glass fiber sleeve.

2. The high temperature insulation layer structure of an alloy induction cable according to claim 1, characterized in that: The glass fibers have 8 to 16 layers.

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