What is the difference between copper conductor and copper alloy cable?

Copper bar is the main raw material of AAC Cable industry. There are two main production methods: continuous casting, continuous rolling and continuous casting. Due to different processes, the oxygen content and appearance of copper rods are also different. When the oxygen content is lower than 10ppm, it is called oxygen free copper rod; When the oxygen content is less than 10ppm, it is called oxygen free copper rod.


Low oxygen copper rod
Disadvantages of process D:
The electrolytic copper melts when it is added. There is no complete reduction condition for copper water. The whole smelting process and copper water process are inseparable from oxygen, so the oxygen content is very high. The fuel for molten copper is usually gas. In the process of gas combustion, it will directly affect the chemical composition of liquid copper. Sulfur and hydrogen are the most important factors.
Process advantages:
(1) High yield. Generally, the output of small units can reach 10-14 tons per hour.
(2) The layout of copper bar adopts plum blossom type, which is convenient for wire drawing machine.
(3) Bearing capacity, generally not more than 4 tons per plate.
Grade and characteristics of low oxygen copper rod: low oxygen copper rod
It is divided into three levels: T1, T2 and T3. The low oxygen copper bar is hot rolled, so it is a soft bar, code R.
(1) T1: production of low oxygen copper rod with high purity electrolytic copper as raw material (copper content greater than 99.9975%).
(2)T2:1 × The low oxygen copper rod (copper content above 99.95%) is made of electrolytic copper.
(3)T3:2 × The low oxygen copper rod (copper content above 99.90%) is made of electrolytic copper. Due to high purity electrolytic copper and 2 × Electrolytic copper is very few, generally 1 × Electrolytic copper is used as raw material, so the grade of low oxygen copper rod is T2R.


Oxygen free copper rod
Oxygen free copper rod is pure copper without oxygen or any deoxidizer residue. But in fact, it still contains a very small amount of oxygen and some impurities. According to the standard, the oxygen content is not more than 0.02%, the total impurity content is not more than 0.05%, and the copper purity is more than 99.95%.
It is generally produced by electrolytic copper, and its resistivity is lower than that of low oxygen copper rod. Therefore, oxygen free copper rod is more economical in the production of products with strict resistance requirements; High quality raw materials are needed to make oxygen free copper rods;
According to the oxygen content and impurity content, the oxygen free copper rod can be divided into TU1 and TU2 copper rods. The purity of TU1 oxygen free copper rod is 99.99%, and the oxygen content is not more than 0.001%; The purity of TU2 oxygen free copper is 99.95%, and the oxygen content is not more than 0.002%.


The difference between the two
Due to different manufacturing methods, low oxygen copper rod and oxygen free copper rod have their own characteristics.
1、 On the removal of oxygen and its existing state
Oxygen content of low oxygen copper rod is generally 200 (175) – 400 (450) ppm, so oxygen is inhaled into liquid copper. On the contrary, the oxygen in the oxygen free copper rod is reduced and removed after a certain period of time. Generally, the oxygen content of bar is below 10-50ppm, and the lowest is 1-2ppm. Oxygen content in oxygen free copper is very low, so the structure of copper is uniform and single-phase, which is conducive to toughness.
2. Difference between impurity content and existing hot rolling defects
The tensile properties of oxygen free copper bar are better than that of oxygen free copper bar in all wire diameters. In addition to the above microstructure reasons, the oxygen content of oxygen free copper bar is less and stable, there is no possible defect in hot rolling, the oxygen monitoring is not strict, and the oxygen content is unstable, which will directly affect the performance of copper bar. If the oxide on the surface of the bar can be made up in the continuous cleaning of the subsequent process, the problem is that there are quite a lot of oxide under the skin, which has a more direct impact on the broken wire.
3. The toughness of low oxygen copper rod is different from that of oxygen free copper rod
Both can be pulled to 0.015 mm, but the distance between low temperature grade oxygen free copper wires is only 0.001 mm.
4. Low oxygen copper rod
The wire making process of copper rod is different from that of oxygen free copper rod. The wire making process of low oxygen copper bar should be the same as that of oxygen free copper bar, at least the annealing process of the two should be different. Because the softness of wire rod is greatly affected by material composition, bar manufacturing, wire manufacturing and annealing process, it can not be simply said that low oxygen copper or oxygen free copper is soft or hard.

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Difference between Fire-Resistant and Flame-Retardant Cables

1 The difference in principle
Fire-resistant cables have different principles from flame-retardant cables. The flame-retardant principle of halogen-containing cable is based on the flame-retardant effect of halogen, and the flame-retardant principle of halogen-free cable is to reduce the temperature of the water to extinguish the fire. Fire-resistant cables rely on the fire-resistant and heat-resistant characteristics of the mica material in the fire-resistant layer to ensure that the cable works normally even in a fire.

2 The difference between structure and material
The structure and materials of fire-resistant cables are different from those of flame-retardant cables.
The basic structure of flame retardant cable is:
(1) The insulating layer is made of flame-retardant materials
(2) Flame-retardant materials are used for the sheath and outer sheath;
(3) The wrapping tape and filling are made of flame retardant materials.

Fire-resistant cables usually add a fire-resistant layer between the conductor and the insulating layer, so theoretically, a fire-resistant layer can be added to the structure of the flame-retardant cable to form a flame-retardant and fire-resistant cable. This is not necessary.

Because of the fire-resistant layer of fire-resistant cables, multi-layer mica tapes are usually used to wrap the wires directly. It can withstand long-term combustion, even if the polymer at the place where the flame is applied is burned, it can ensure the normal operation of the line.

3. What is the difference in the structure of flame-retardant, fire-resistant, and flame-retardant fire-resistant cables?

The structure of flame-retardant cables is basically the same as that of ordinary cables. The difference lies in its insulating layer, sheath, outer sheath and auxiliary materials (wrap tape and Filling) all or part of the flame-retardant material is used, and the fire-resistant cable usually adds a fire-resistant layer between the bare conductor and the insulating layer. Therefore, theoretically, a fire-resistant layer can be added to the structure of the flame-retardant cable to form Both flame-retardant and fire-resistant cables, but this is not actually necessary. Because of the fire-resistant layer of fire-resistant cables, multi-layer mica tapes are usually directly wrapped on the wires. It can withstand long-term burning. Even if the high polymer at the place where the flame is applied is burned, the normal operation of the line can be guaranteed.

4. What is the difference between low-smoke and halogen-free cables, low-smoke and halogen-free fire-resistant cables and low-smoke and halogen-free flame-retardant and fire-resistant cables?

As the name suggests, it is the difference in sheath materials. Low-smoke and halogen-free is environmentally friendly, that is, it does not produce a large amount of toxic gas during combustion, which ensures the safety of relevant places. Fire resistance means being able to stay in the flame without melting. Ordinary is a general sheath material.

5. The classification principles of flame retardant a, b, and C levels and what is the difference in structure are divided according to standard regulations. They are used to evaluate the ability of vertically installed bundles of wires and cables or optical cables to inhibit the vertical spread of flame under specified conditions:
Flame retardant Class A refers to: the cable is installed on the test steel ladder so that the total volume of the non-metallic materials contained in the test is 40 minutes, and the cable is burned to dry the sample. The maximum carbon circumference of the test sample shall not be higher than the bottom resistance of the blowtorch.

The flame-retardant type B cable is installed on the test steel ladder so that the test material in the total volume is the burning and drying test sample, and the maximum carbon circumference of the test sample shall not be higher than the bottom of the blowtorch
The flame-retardant type C is installed on the test steel ladder so that the total volume of the non-metallic materials in the test is 5/m, and the fire time is 20 minutes. After the cable burning stops, dry the sample, and the maximum carbonization of the sample is measured. Not higher than the bottom of the blowtorch