Advantage analysis of aluminum alloy cable compared with ordinary cable
What are the advantages of aluminum alloy cables over ordinary cables?
1. Conductive properties: The electrical conductivity of aluminum alloy is 61.5% of the most commonly used reference material copper IACS, and the current carrying capacity is 79% of copper, which is superior to the pure aluminum standard.
2. Creep resistance: The alloy material and annealing treatment of aluminum alloy conductors reduce the "creep" tendency of the conductor under heat and pressure. Compared with pure aluminum, the creep resistance is improved by 300%, avoiding cold flow. Or the problem of relaxation caused by creep.
3. Tensile strength and elongation: aluminum alloy conductor compared to pure aluminum conductor, due to the addition of special components and the use of special processing technology, greatly improved the tensile strength, and the elongation increased to 30%, It is safer and more reliable to use.
4. Thermal expansion coefficient: The thermal expansion coefficient is used to calculate the dimensional change of the material when the temperature changes. Aluminum alloys have a thermal expansion coefficient comparable to that of copper. Aluminum connectors have been used reliably for copper and aluminum conductors for many years, and most of the electrical connectors used today are made of aluminum, which is especially suitable for aluminum alloys. Therefore, the aluminum alloy conductor is completely identical to the expansion and contraction of the connector.
5. Strong self-weight bearing capacity The aluminum alloy improves the tensile strength of pure aluminum. The aluminum alloy cable can support the self-weight of 4000 meters in length, and the copper cable can only support 2750 meters. This advantage is particularly evident when wiring large-span buildings such as stadiums.
6. Anti-corrosion properties The inherent corrosion resistance of aluminum comes from the formation of a thin and strong oxide layer when the aluminum surface is in contact with air. This oxide layer is particularly resistant to various forms of corrosion. The rare earth element added in the alloy can further improve the corrosion resistance of the aluminum alloy, especially electrochemical corrosion. The ability of aluminum to withstand harsh environments has made it widely used as a conductor for cables in trays, as well as many industrial components and containers. Corrosion is usually associated with the connection of different metals in a humid environment, and appropriate protective measures can be used to prevent corrosion, such as the use of lubricating oils, antioxidants and protective coatings. Alkaline soils and certain types of acidic soil environments are highly corrosive to aluminum, so direct-buried aluminum conductors should be insulated or molded to prevent corrosion. In sulfur-containing environments, such as railway tunnels and the like, aluminum alloys have much better corrosion resistance than copper.
7. Flexibility The aluminum alloy has good bending properties, and its unique alloy formula and processing technology greatly improve the flexibility. Aluminum alloy is 30% more flexible than copper, and its rebound is 40% lower than copper. Generally, the bending radius of the copper cable is 10 to 20 times the outer diameter, and the bending radius of the aluminum alloy cable is only 7 times the outer diameter, which makes it easier to connect the terminals.
8. Outfitting characteristics Most commonly used armored cables in China are equipped with steel tape armor, which has low safety level. When subjected to external destructive force, its resistance is poor, it is easy to cause breakdown, and the weight is heavy, and the installation cost is quite high. Poor corrosion resistance and long service life. The metal chain armored cable developed by us according to American standards uses aluminum alloy with chain armor, and the interlocking structure between layers ensures that the cable can withstand strong external destructive forces, even if the cable is under greater pressure. When the impact force is applied, the cable is not easily broken down, which improves the safety performance. At the same time, the armored structure isolates the cable from the outside. Even in the event of fire, the armor layer improves the flame retardant and fire resistance of the cable and reduces the risk factor of fire. The aluminum alloy belt armored structure is lighter than the steel belt armor. It is easy to lay and can be installed without the bridge, which can reduce the installation cost by 20%~40%. Different outer sheath layers can be selected depending on the place of use, making the use of armored cables more widely used.
9. Squeezing characteristics alone In terms of volumetric conductivity, aluminum alloys are not as good as copper. However, the conductors we developed have not only improved the material properties, but also made great breakthroughs in the process. We use ultra-conventional pressing technology. The compaction coefficient can reach 0.93, and the compaction coefficient of the profiled line can reach 0.95, which is the first in China. Through the maximum limit of compaction, it can make up for the shortage of volumetric conductivity of aluminum alloy cable, so that the stranded conductor core is like a solid conductor, which obviously reduces the outer diameter of the core and improves the conductivity. The conductor is under the same current carrying capacity. The outer diameter is only 10% larger than the copper cable.