What are the advantages of aluminum alloy cable over ordinary cable?
1. Electrical conductivity: the conductivity of aluminum alloy is 61.5% of copper IACS, and the current carrying capacity is 79% of copper, which is better than pure aluminum standard.
2. Creep resistance: the alloy material and annealing process of aluminum alloy conductor reduce the "creep" tendency of conductor under heating and pressure. Compared with pure aluminum, the creep resistance can be increased by 300%, avoiding the relaxation problem caused by cold flow or creep.
3. Tensile strength and elongation: compared with pure aluminum conductor, aluminum alloy conductor greatly improves tensile strength and elongation to 30% due to the addition of special components and special processing technology, which is safer and more reliable.
4. Coefficient of thermal expansion: the coefficient of thermal expansion is used to calculate the size change of materials when the temperature changes. The thermal expansion coefficient of aluminum alloy is similar to that of copper. For many years aluminum connectors have been used reliably in copper and aluminum conductors. Most of the electrical connectors used today are made of aluminum, which is especially suitable for aluminum alloy. Therefore, the expansion and contraction of aluminum alloy conductor and connector are completely consistent.
5. Aluminum alloy cable can support 4000 meters of dead weight, while copper cable can only support 2750 meters. This advantage is particularly prominent in the wiring of large-span buildings (such as stadiums).
6. Corrosion resistance the inherent corrosion resistance of aluminum is due to the formation of a thin and strong oxide layer when the aluminum surface is in contact with air, which is particularly resistant to various forms of corrosion. The addition of rare earth elements in the alloy can further improve the corrosion resistance of aluminum alloy, especially the electrochemical corrosion. Aluminum is widely used as conductor of cable in tray, as well as many industrial components and containers because of its ability to withstand harsh environment. Corrosion is usually associated with the joining of different metals in a humid environment, and appropriate protective measures can be used to prevent corrosion, such as the use of lubricants, antioxidants and protective coatings. Alkaline soil and some types of acid soil environment have greater corrosivity to aluminum, so the directly buried aluminum conductor should use insulating layer or molded sheath to prevent corrosion. In sulfur-containing environment, such as railway tunnels and other similar places, the corrosion resistance of aluminum alloy is much better than that of copper.
7. Flexible aluminum alloy has good bending properties. Its unique alloy formula and processing technology greatly improve the flexibility. Aluminum alloy is 30% more flexible than copper and 40% lower than copper. Generally, the bending radius of copper cable is 10 ~ 20 times of outer diameter, while that of aluminum alloy cable is only 7 times of outer diameter.
8. Armor characteristics: most of the armored cables commonly used in China are steel belt armored, with low safety level. When subjected to external destructive force, it has poor resistance, easy to cause breakdown, heavy weight, high installation cost, poor corrosion resistance and short service life. The metal interlocking armored cable developed according to American standard adopts aluminum alloy belt interlocking armor. The interlocking structure between layers ensures that the cable can withstand strong external destructive force. Even when the cable is subjected to large pressure and impact force, the cable is not easy to be broken down, which improves the safety performance. At the same time, the armored structure makes the cable isolated from the outside. Even in case of fire, the armor layer improves the fire resistance level of the cable and reduces the fire risk factor. Compared with steel belt armored structure, aluminum alloy belt armored structure has the advantages of light weight, convenient laying, free of bridge installation, and can reduce installation cost by 20% ~ 40%. Different outer sheath layers can be selected according to different places of use to make the armored cable more widely used.
9. Considering the volume conductivity, aluminum alloy is not as good as copper. However, the conductor developed by us has not only made improvement in material properties, but also made great breakthrough in technology. We use unconventional compaction technology to make the compression coefficient reach 0.93, while that of profiled wire can reach 0.95, which is the first in China. Through the maximum limit of compression, the aluminum alloy cable can make up for the lack of volume conductivity, so that the stranded conductor core is like a solid conductor, which can significantly reduce the outer diameter of the core and improve the conductivity. Under the same current carrying capacity, the outer diameter of the conductor is only 10% larger than that of the copper cable.
1. Electrical conductivity: the conductivity of aluminum alloy is 61.5% of copper IACS, and the current carrying capacity is 79% of copper, which is better than pure aluminum standard.
2. Creep resistance: the alloy material and annealing process of aluminum alloy conductor reduce the "creep" tendency of conductor under heating and pressure. Compared with pure aluminum, the creep resistance can be increased by 300%, avoiding the relaxation problem caused by cold flow or creep.
3. Tensile strength and elongation: compared with pure aluminum conductor, aluminum alloy conductor greatly improves tensile strength and elongation to 30% due to the addition of special components and special processing technology, which is safer and more reliable.
4. Coefficient of thermal expansion: the coefficient of thermal expansion is used to calculate the size change of materials when the temperature changes. The thermal expansion coefficient of aluminum alloy is similar to that of copper. For many years aluminum connectors have been used reliably in copper and aluminum conductors. Most of the electrical connectors used today are made of aluminum, which is especially suitable for aluminum alloy. Therefore, the expansion and contraction of aluminum alloy conductor and connector are completely consistent.
5. Aluminum alloy cable can support 4000 meters of dead weight, while copper cable can only support 2750 meters. This advantage is particularly prominent in the wiring of large-span buildings (such as stadiums).
6. Corrosion resistance the inherent corrosion resistance of aluminum is due to the formation of a thin and strong oxide layer when the aluminum surface is in contact with air, which is particularly resistant to various forms of corrosion. The addition of rare earth elements in the alloy can further improve the corrosion resistance of aluminum alloy, especially the electrochemical corrosion. Aluminum is widely used as conductor of cable in tray, as well as many industrial components and containers because of its ability to withstand harsh environment. Corrosion is usually associated with the joining of different metals in a humid environment, and appropriate protective measures can be used to prevent corrosion, such as the use of lubricants, antioxidants and protective coatings. Alkaline soil and some types of acid soil environment have greater corrosivity to aluminum, so the directly buried aluminum conductor should use insulating layer or molded sheath to prevent corrosion. In sulfur-containing environment, such as railway tunnels and other similar places, the corrosion resistance of aluminum alloy is much better than that of copper.
7. Flexible aluminum alloy has good bending properties. Its unique alloy formula and processing technology greatly improve the flexibility. Aluminum alloy is 30% more flexible than copper and 40% lower than copper. Generally, the bending radius of copper cable is 10 ~ 20 times of outer diameter, while that of aluminum alloy cable is only 7 times of outer diameter.
8. Armor characteristics: most of the armored cables commonly used in China are steel belt armored, with low safety level. When subjected to external destructive force, it has poor resistance, easy to cause breakdown, heavy weight, high installation cost, poor corrosion resistance and short service life. The metal interlocking armored cable developed according to American standard adopts aluminum alloy belt interlocking armor. The interlocking structure between layers ensures that the cable can withstand strong external destructive force. Even when the cable is subjected to large pressure and impact force, the cable is not easy to be broken down, which improves the safety performance. At the same time, the armored structure makes the cable isolated from the outside. Even in case of fire, the armor layer improves the fire resistance level of the cable and reduces the fire risk factor. Compared with steel belt armored structure, aluminum alloy belt armored structure has the advantages of light weight, convenient laying, free of bridge installation, and can reduce installation cost by 20% ~ 40%. Different outer sheath layers can be selected according to different places of use to make the armored cable more widely used.
9. Considering the volume conductivity, aluminum alloy is not as good as copper. However, the conductor developed by us has not only made improvement in material properties, but also made great breakthrough in technology. We use unconventional compaction technology to make the compression coefficient reach 0.93, while that of profiled wire can reach 0.95, which is the first in China. Through the maximum limit of compression, the aluminum alloy cable can make up for the lack of volume conductivity, so that the stranded conductor core is like a solid conductor, which can significantly reduce the outer diameter of the core and improve the conductivity. Under the same current carrying capacity, the outer diameter of the conductor is only 10% larger than that of the copper cable.