TST CABLES aluminum alloy cable is a new material power cable. Aluminum alloy power cable is a new material power cable with AA8030 series aluminum alloy material as conductor, special roll-formed wire stranding production process and annealing treatment and other advanced technologies. Alloy power cable makes up for the shortcomings of pure aluminum cable in the past. Although the electrical conductivity of the cable has not been improved, the bending performance, creep resistance and corrosion resistance have been greatly improved, which can ensure that the cable can maintain continuous performance stability when overloaded and overheated for a long time. The use of AA-8030 series aluminum alloy conductor can greatly improve the conductivity and high temperature resistance of aluminum alloy cable, and solve the problems of pure aluminum conductor and creep.
The conductivity of aluminum alloy is 61.8% of the most commonly used reference material copper IACS, and the current carrying capacity is 79% of copper, which is better than the pure aluminum standard. However, under the same volume, the actual weight of aluminum alloy is about one-third of copper. Therefore, the weight of aluminum alloy cable is about half of that of copper cable at the same current carrying capacity. TST CABLES uses aluminum alloy cables to replace copper cables, which can reduce the weight of cables, reduce installation costs, reduce wear and tear on equipment and cables, and make installation easier.
Aluminum alloy cable performance advantages
Aluminum alloy cable safety performance
1. Historical practice proves
Aluminum alloy cable has been developed and used in the United States for 53 years since 1968. The product has been widely used, with a market share of 80% in North American countries. After 53 years of practice, it has been proved that aluminum alloy cable has never had any failures and is safe.
2. Testing and certification
Aluminum alloy cable has passed the testing and certification of international authoritative organizations such as UL in the United States, CUL in Canada, SAI GLOBAI in Australia, and China National Cable and Wire Testing Center, State Grid Wuhan High Voltage Research Institute, and National Fireproof Building Materials Quality Supervision and Inspection Center. The aluminum alloy conductor meets the requirements of CSA standard C22.2 Clause 38 on ACM alloy conductors, and the performance requirements of the latest versions of GB12706.1–2008 and IEC60502.1, as well as UL’s standards related to the AA8000 series.
3. Effect of aluminum alloy components
After rare earth and iron are added to the aluminum alloy conductor, its conductivity and connection performance are greatly improved, especially when the conductor is annealed, the addition of iron produces high-strength anti-creep performance. When the current is overloaded, the iron plays a continuous connection role, so that the aluminum alloy conductor will not creep.
Creep is extremely harmful to cables. If the cable creeps, its contact point is not pressed tightly enough, the pressure is reduced, and the contact resistance increases rapidly. After the current flows through, the joint will overheat. If it is not regularly inspected, there will be safety hazards. It is very important to solve the cable creep problem.
Creep: Under the action of temperature, external force and deadweight, metal will slowly produce permanent deformation that cannot be restored over time. This phenomenon is creep.
4. Flame retardant performance
The insulation material of aluminum alloy cable is flame-retardant silane cross-linked polyethylene (XLPE cable), and the process adopts a self-locking armor structure. The heat dissipation performance is far better than the sheath of PVC material. It can dissipate heat quickly. After the flame disappears, the flame can be extinguished quickly without delaying other materials. The flame retardant performance is extremely excellent. Aluminum alloy cables use new materials and new processes to ensure that they are safer to use.
Aluminum alloy cable electrical performance
1. Cable current carrying capacity
When the cross-sectional area of the alloy conductor is 1.5 times that of copper, the electrical performance of the alloy conductor is the same as that of the copper conductor, achieving the same current carrying capacity, resistance, and voltage loss.
The resistivity of aluminum alloy is between aluminum and copper, higher than copper and slightly lower than aluminum. Under the same current carrying capacity, the weight of an aluminum alloy conductor of the same length is only half that of copper. If the conductivity of copper is 100%, the conductivity of the alloy conductor is about 61.2%, the specific gravity of the alloy is 2.7, and the specific gravity of copper is 8.9, then (8.9/2.7)×(0.612/1)=2, that is, the resistance of 2 units of copper is the same as the resistance of 1 unit of alloy. Therefore, when the cross-sectional area of the alloy conductor is 1.5 times that of copper, its electrical performance is the same, that is, it achieves the same current carrying capacity, resistance, and voltage loss as copper.
There are many factors that affect the current carrying capacity of power cables, such as line characteristics (such as working voltage, current type, frequency, load factors); structure of wires and cables (such as structure of conductive core, number of cores, type of insulation material, structure and material of shielding layer and inner and outer sheath, total outer diameter); laying conditions (such as laying in air, laying in pipelines, direct burial, laying in underground trenches, laying in water); maximum allowable operating temperature of conductive core and surrounding environmental conditions (such as air and soil temperature, soil thermal resistance coefficient, proximity effect of surrounding heat sources), etc.
2. Reduce the outer cross-section of the cable
In the production process of aluminum alloy cable, Germany’s most advanced compacting technology enables the filling factor of its conductor to reach 93%. In addition, aluminum alloy cable uses silane cross-linked polyethylene, which only needs 2/3 of the thickness of polyvinyl chloride to far exceed the conventional insulation performance. The filling factor of copper can generally only reach 80%, and the commonly used insulation is polyvinyl chloride, so the outer diameter of aluminum alloy cable only needs to increase by less than 11% on the basis of copper cable to have the same electrical performance as copper. It can be seen that the use of aluminum alloy cables does not require changing the original pipeline design of copper cables. (Generally, the size of the laying pipeline designed by the designer is 150% of the copper cable, so pipe threading is not a problem.)
3. Reduce cable line loss
Non-magnetic materials will not generate eddy currents, which can reduce line losses. Aluminum alloy belts and armor locks are non-magnetic materials. Even if there is a three-phase unbalanced current, eddy currents will not be generated, which can reduce line losses.
Mechanical properties of aluminum alloy cables
1. Elongation performance of aluminum alloy cables
Elongation is an important indicator of the mechanical properties of conductors. It is an important indicator of the quality of products and the external force they can withstand. It is also an important indicator for testing the mechanical properties of cable conductors. The elongation of aluminum alloy cables after annealing can reach 30%, while the elongation of copper cables is 25%, and the elongation of ordinary aluminum rods is 15%. It is an important indicator that can replace aluminum core cables and copper cables.
2. Flexibility of aluminum alloy cables
Torsion test: mainly tests the toughness of metal wires. The better the toughness, the more torsion times it can withstand. An important disadvantage of ordinary aluminum wire is its high brittleness. During installation, as long as it is twisted at a certain angle several times, the conductor will crack, and the crack will heat up and corrode, which is an important cause of fire. The use of aluminum alloy cable, due to its good toughness, will not produce cracks, and the safety hazards during installation are reduced.
3. Bending performance of aluminum alloy cable
Bending test: mainly tests the bending resistance of metal. Materials with uneven materials or brittle properties have poor bending resistance.
According to the provisions of GB/T12706 on the bending radius of copper cables during installation, the bending radius of copper cables is 10-20 times the cable diameter, and the minimum bending radius of aluminum alloy cables is 7 times the cable diameter. The use of aluminum alloy cables can reduce the layout space, make it easier to lay, and reduce installation costs.
4. Rebound performance of aluminum alloy cables
Practice has proved that when copper cables and aluminum alloy cables are bent 90 degrees at room temperature, after stress release, the rebound angle of aluminum alloy cables is 60% of that of copper cables. Because aluminum alloy cables have no memory, their rebound performance is better than that of copper core cables. During installation, the terminal connection joints are easy to tighten, increasing their tightness and improving the stability of the connection.
Also available in:
English
